Logistic regression applied to natural hazards: rare event logistic regression with replications

Science.gov (United States)

Guns, M.; Vanacker, V.

2012-06-01

Statistical analysis of natural hazards needs particular attention, as most of these phenomena are rare events. This study shows that the ordinary rare event logistic regression, as it is now commonly used in geomorphologic studies, does not always lead to a robust detection of controlling factors, as the results can be strongly sample-dependent. In this paper, we introduce some concepts of Monte Carlo simulations in rare event logistic regression. This technique, so-called rare event logistic regression with replications, combines the strength of probabilistic and statistical methods, and allows overcoming some of the limitations of previous developments through robust variable selection. This technique was here developed for the analyses of landslide controlling factors, but the concept is widely applicable for statistical analyses of natural hazards.

Correlation, Regression and Path Analyses of Seed Yield Components in Crambe abyssinica, a Promising Industrial Oil Crop

OpenAIRE

Huang, Banglian; Yang, Yiming; Luo, Tingting; Wu, S.; Du, Xuezhu; Cai, Detian; Loo, van, E.N.; Huang Bangquan

2013-01-01

In the present study correlation, regression and path analyses were carried out to decide correlations among the agro- nomic traits and their contributions to seed yield per plant in Crambe abyssinica. Partial correlation analysis indicated that plant height (X1) was significantly correlated with branching height and the number of first branches (P <0.01); Branching height (X2) was significantly correlated with pod number of primary inflorescence (P <0.01) and number of secondary branch...

Floral function: effects of traits on pollinators, male and female pollination success, and female fitness across three species of milkweeds (Asclepias).

Science.gov (United States)

La Rosa, Raffica J; Conner, Jeffrey K

2017-01-01

Central questions in plant reproductive ecology are whether the functions of floral traits in hermaphrodites create conflict between sexes that could slow evolution, and whether individual floral traits function in pollinator attraction, efficiency, or both. We studied how floral traits affect pollinator visitation and efficiency, and how they affect male and female function and female fitness within and across three Asclepias species that differ in floral morphology. Using separate multiple regressions, we regressed pollen removal, deposition, and fruit number onto six floral traits. We also used path analyses integrating these variables with pollinator visitation data for two of the species to further explore floral function and its effects on fruit production. Most traits affected male pollination success only, and these effects often differed between species. The exception was increased slit length, which increased pollinia insertion in two of the species. There were no interspecific differences in the effects of the traits on female pollination success. All traits except horn reach affected pollination efficiency in at least one species, and horn reach and two hood dimensions were the only traits to affect pollinator attraction, but in just one species. Traits tended to function in only one sex, and more traits affected function through pollinator efficiency than through attraction. There was no significant link between female pollination success and female fitness in any of the three species; this pattern is consistent with fruit production not being limited by pollen deposition. © 2017 Botanical Society of America.

Logistic regression applied to natural hazards: rare event logistic regression with replications

Directory of Open Access Journals (Sweden)

M. Guns

2012-06-01

Full Text Available Statistical analysis of natural hazards needs particular attention, as most of these phenomena are rare events. This study shows that the ordinary rare event logistic regression, as it is now commonly used in geomorphologic studies, does not always lead to a robust detection of controlling factors, as the results can be strongly sample-dependent. In this paper, we introduce some concepts of Monte Carlo simulations in rare event logistic regression. This technique, so-called rare event logistic regression with replications, combines the strength of probabilistic and statistical methods, and allows overcoming some of the limitations of previous developments through robust variable selection. This technique was here developed for the analyses of landslide controlling factors, but the concept is widely applicable for statistical analyses of natural hazards.

Regression analysis with categorized regression calibrated exposure: some interesting findings

Directory of Open Access Journals (Sweden)

Hjartåker Anette

2006-07-01

Full Text Available Abstract Background Regression calibration as a method for handling measurement error is becoming increasingly well-known and used in epidemiologic research. However, the standard version of the method is not appropriate for exposure analyzed on a categorical (e.g. quintile scale, an approach commonly used in epidemiologic studies. A tempting solution could then be to use the predicted continuous exposure obtained through the regression calibration method and treat it as an approximation to the true exposure, that is, include the categorized calibrated exposure in the main regression analysis. Methods We use semi-analytical calculations and simulations to evaluate the performance of the proposed approach compared to the naive approach of not correcting for measurement error, in situations where analyses are performed on quintile scale and when incorporating the original scale into the categorical variables, respectively. We also present analyses of real data, containing measures of folate intake and depression, from the Norwegian Women and Cancer study (NOWAC. Results In cases where extra information is available through replicated measurements and not validation data, regression calibration does not maintain important qualities of the true exposure distribution, thus estimates of variance and percentiles can be severely biased. We show that the outlined approach maintains much, in some cases all, of the misclassification found in the observed exposure. For that reason, regression analysis with the corrected variable included on a categorical scale is still biased. In some cases the corrected estimates are analytically equal to those obtained by the naive approach. Regression calibration is however vastly superior to the naive method when applying the medians of each category in the analysis. Conclusion Regression calibration in its most well-known form is not appropriate for measurement error correction when the exposure is analyzed on a

Female Directors and Firm Performance: Evidence from UK Listed Firms

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Pananda Pasaribu

2017-08-01

Full Text Available The impact of female directors on firm performance has lacked consistency in the previously conducted empirical studies, which may be due to the endogeneity problem, or certain characteristics (i.e. governance, industry, competition. This study examines the relationship between female directors and firm performance by addressing those problems. This study analyses all non-financial UK listed firms during the period 2004-2012 and employs several econometric models. The regression results indicate that there is little evidence that female directors have a positive and strong relationship with firm performance. But, further analysis reports that the UK’s small listed firms experience a positive significant effect, because small firms do not suffer from the problem of over-monitoring and they have more flexibility in composing their boards of directors.

Genetic analyses of partial egg production in Japanese quail using multi-trait random regression models.

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Karami, K; Zerehdaran, S; Barzanooni, B; Lotfi, E

2017-12-01

1. The aim of the present study was to estimate genetic parameters for average egg weight (EW) and egg number (EN) at different ages in Japanese quail using multi-trait random regression (MTRR) models. 2. A total of 8534 records from 900 quail, hatched between 2014 and 2015, were used in the study. Average weekly egg weights and egg numbers were measured from second until sixth week of egg production. 3. Nine random regression models were compared to identify the best order of the Legendre polynomials (LP). The most optimal model was identified by the Bayesian Information Criterion. A model with second order of LP for fixed effects, second order of LP for additive genetic effects and third order of LP for permanent environmental effects (MTRR23) was found to be the best. 4. According to the MTRR23 model, direct heritability for EW increased from 0.26 in the second week to 0.53 in the sixth week of egg production, whereas the ratio of permanent environment to phenotypic variance decreased from 0.48 to 0.1. Direct heritability for EN was low, whereas the ratio of permanent environment to phenotypic variance decreased from 0.57 to 0.15 during the production period. 5. For each trait, estimated genetic correlations among weeks of egg production were high (from 0.85 to 0.98). Genetic correlations between EW and EN were low and negative for the first two weeks, but they were low and positive for the rest of the egg production period. 6. In conclusion, random regression models can be used effectively for analysing egg production traits in Japanese quail. Response to selection for increased egg weight would be higher at older ages because of its higher heritability and such a breeding program would have no negative genetic impact on egg production.

Reproductive efficiency of captive Chinese- and Indian-origin rhesus macaque (Macaca mulatta) females

Science.gov (United States)

Kubisch, H. Michael; Falkenstein, Kathrine P.; Deroche, Chelsea B.; Franke, Donald E.

2011-01-01

Reproductive and survival records (n = 2,913) from 313 Chinese-origin and 365 Indian-derived rhesus macaques at the Tulane National Primate Research Center spanning 3 generations were studied. Least-squares analysis of variance procedures were used to compare reproductive and infant survival traits while proportional hazards regression procedures were used to study female age at death, number of infants born per female and time from last birth to death. Chinese females were older at first parturition than Indian-females because they were older when placed with males, but the two subspecies had similar first and lifetime post-partum birth intervals. Females that gave birth to stillborn infants had shorter first post-partum birth intervals than females giving birth to live infants. Post-partum birth intervals decreased in females from 3 to 12 years of age but then increased again with advancing age. Chinese infants had a greater survival rate than Indian infants at 30 d, 6 mo and 1yr of age. Five hundred and forty-three females (80.01 %) had uncensored, or true records for age at death, number of infants born per female, and time from the birth until death whereas 135 females (19.91 %) had censored records for these traits. Low and high uncensored observations for age at death were 3 and 26 years of age for Chinese and 3 and 23 years of age for Indian females. Uncensored number of infants born per female ranged from 1 to 15 for Chinese females and 1 to 18 for Indian females. Each of these traits was significantly influenced by the origin × generation interaction in the proportional hazards regression analyses, indicating that probabilities associated with age at death, number of infants born per female and time from last birth to death for Chinese and Indian females did not rank the same across generations. PMID:22512021

Association between Travel Times and Food Procurement Practices among Female Supplemental Nutrition Assistance Program Participants in Eastern North Carolina

Science.gov (United States)

Jilcott, Stephanie B.; Moore, Justin B.; Wall-Bassett, Elizabeth D.; Liu, Haiyong; Saelens, Brian E.

2011-01-01

Objective: To examine associations between self-reported vehicular travel behaviors, perceived stress, food procurement practices, and body mass index among female Supplemental Nutrition Assistance Program (SNAP) participants. Analysis: The authors used correlation and regression analyses to examine cross-sectional associations between travel time…

[Gender differences in career motivation: female doctors' ambitions benefit from family friendly work environment].

Science.gov (United States)

Pas, B R; Lagro-Janssen, A L M; Doorewaard, J A C M; Eisinga, R N; Peters, C P

2008-10-04

To determine gender differences in career motivation and the effect of a family friendly work environment. Cross-sectional pilot investigation. A web survey among male and female doctors (n = 107; 72 women and 35 men) in different specialties, including surgical, internal medicine and general practitioners, was used to gather information on different dimensions of career motivation and perceptions of the family friendliness of the work environment. Differences were analysed by means of t-tests and regression analyses. Male doctors had higher scores on career identity and on career planning than female doctors. However, male and female doctors did not differ in their willingness to achieve top positions. Female doctors were more determined concerning their career goals than their male counterparts. The family friendliness of the work environment had an overall positive effect on career motivation for both male and female doctors. However, a family friendly work environment had a negative effect on the career identity of male doctors. For male and female doctors alike, support to achieve career goals and elimination of career barriers lead to increased career identity. Male and female doctors differed in certain dimensions of career motivation. Offering support for career goals and taking away career barriers leads to a higher career motivation than offering a family friendly work environment.

Grades, Gender, and Encouragement: A Regression Discontinuity Analysis

Science.gov (United States)

Owen, Ann L.

2010-01-01

The author employs a regression discontinuity design to provide direct evidence on the effects of grades earned in economics principles classes on the decision to major in economics and finds a differential effect for male and female students. Specifically, for female students, receiving an A for a final grade in the first economics class is…

Analyses of Developmental Rate Isomorphy in Ectotherms: Introducing the Dirichlet Regression.

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David S Boukal

Full Text Available Temperature drives development in insects and other ectotherms because their metabolic rate and growth depends directly on thermal conditions. However, relative durations of successive ontogenetic stages often remain nearly constant across a substantial range of temperatures. This pattern, termed 'developmental rate isomorphy' (DRI in insects, appears to be widespread and reported departures from DRI are generally very small. We show that these conclusions may be due to the caveats hidden in the statistical methods currently used to study DRI. Because the DRI concept is inherently based on proportional data, we propose that Dirichlet regression applied to individual-level data is an appropriate statistical method to critically assess DRI. As a case study we analyze data on five aquatic and four terrestrial insect species. We find that results obtained by Dirichlet regression are consistent with DRI violation in at least eight of the studied species, although standard analysis detects significant departure from DRI in only four of them. Moreover, the departures from DRI detected by Dirichlet regression are consistently much larger than previously reported. The proposed framework can also be used to infer whether observed departures from DRI reflect life history adaptations to size- or stage-dependent effects of varying temperature. Our results indicate that the concept of DRI in insects and other ectotherms should be critically re-evaluated and put in a wider context, including the concept of 'equiproportional development' developed for copepods.

Female children with incarcerated adult family members at risk for life-long neurological decline

OpenAIRE

Brewer-Smyth, Kathleen; Pohlig, Ryan T.; Bucurescu, Gabriel

2016-01-01

A secondary analysis of data from adult female prison inmates in the mid-Atlantic United States defined relationships between having incarcerated adult family members during childhood and neurological outcomes. Of 135 inmates, 99(73%) had one or more incarcerated adult family members during childhood. Regression analyses revealed that having incarcerated adult family members was related to greater frequency and severity of childhood abuse and higher incidence of neurological deficits in adult...

Comparison of Classical Linear Regression and Orthogonal Regression According to the Sum of Squares Perpendicular Distances

OpenAIRE

KELEŞ, Taliha; ALTUN, Murat

2016-01-01

Regression analysis is a statistical technique for investigating and modeling the relationship between variables. The purpose of this study was the trivial presentation of the equation for orthogonal regression (OR) and the comparison of classical linear regression (CLR) and OR techniques with respect to the sum of squared perpendicular distances. For that purpose, the analyses were shown by an example. It was found that the sum of squared perpendicular distances of OR is smaller. Thus, it wa...

Comparison of cranial sex determination by discriminant analysis and logistic regression.

Science.gov (United States)

Amores-Ampuero, Anabel; Alemán, Inmaculada

2016-04-05

Various methods have been proposed for estimating dimorphism. The objective of this study was to compare sex determination results from cranial measurements using discriminant analysis or logistic regression. The study sample comprised 130 individuals (70 males) of known sex, age, and cause of death from San José cemetery in Granada (Spain). Measurements of 19 neurocranial dimensions and 11 splanchnocranial dimensions were subjected to discriminant analysis and logistic regression, and the percentages of correct classification were compared between the sex functions obtained with each method. The discriminant capacity of the selected variables was evaluated with a cross-validation procedure. The percentage accuracy with discriminant analysis was 78.2% for the neurocranium (82.4% in females and 74.6% in males) and 73.7% for the splanchnocranium (79.6% in females and 68.8% in males). These percentages were higher with logistic regression analysis: 85.7% for the neurocranium (in both sexes) and 94.1% for the splanchnocranium (100% in females and 91.7% in males).

Improved Dietary Guidelines for Vitamin D: Application of Individual Participant Data (IPD)-Level Meta-Regression Analyses

Science.gov (United States)

Cashman, Kevin D.; Ritz, Christian; Kiely, Mairead

2017-01-01

Dietary Reference Values (DRVs) for vitamin D have a key role in the prevention of vitamin D deficiency. However, despite adopting similar risk assessment protocols, estimates from authoritative agencies over the last 6 years have been diverse. This may have arisen from diverse approaches to data analysis. Modelling strategies for pooling of individual subject data from cognate vitamin D randomized controlled trials (RCTs) are likely to provide the most appropriate DRV estimates. Thus, the objective of the present work was to undertake the first-ever individual participant data (IPD)-level meta-regression, which is increasingly recognized as best practice, from seven winter-based RCTs (with 882 participants ranging in age from 4 to 90 years) of the vitamin D intake–serum 25-hydroxyvitamin D (25(OH)D) dose-response. Our IPD-derived estimates of vitamin D intakes required to maintain 97.5% of 25(OH)D concentrations >25, 30, and 50 nmol/L across the population are 10, 13, and 26 µg/day, respectively. In contrast, standard meta-regression analyses with aggregate data (as used by several agencies in recent years) from the same RCTs estimated that a vitamin D intake requirement of 14 µg/day would maintain 97.5% of 25(OH)D >50 nmol/L. These first IPD-derived estimates offer improved dietary recommendations for vitamin D because the underpinning modeling captures the between-person variability in response of serum 25(OH)D to vitamin D intake. PMID:28481259

Improved Dietary Guidelines for Vitamin D: Application of Individual Participant Data (IPD-Level Meta-Regression Analyses

Directory of Open Access Journals (Sweden)

Kevin D. Cashman

2017-05-01

Full Text Available Dietary Reference Values (DRVs for vitamin D have a key role in the prevention of vitamin D deficiency. However, despite adopting similar risk assessment protocols, estimates from authoritative agencies over the last 6 years have been diverse. This may have arisen from diverse approaches to data analysis. Modelling strategies for pooling of individual subject data from cognate vitamin D randomized controlled trials (RCTs are likely to provide the most appropriate DRV estimates. Thus, the objective of the present work was to undertake the first-ever individual participant data (IPD-level meta-regression, which is increasingly recognized as best practice, from seven winter-based RCTs (with 882 participants ranging in age from 4 to 90 years of the vitamin D intake–serum 25-hydroxyvitamin D (25(OHD dose-response. Our IPD-derived estimates of vitamin D intakes required to maintain 97.5% of 25(OHD concentrations >25, 30, and 50 nmol/L across the population are 10, 13, and 26 µg/day, respectively. In contrast, standard meta-regression analyses with aggregate data (as used by several agencies in recent years from the same RCTs estimated that a vitamin D intake requirement of 14 µg/day would maintain 97.5% of 25(OHD >50 nmol/L. These first IPD-derived estimates offer improved dietary recommendations for vitamin D because the underpinning modeling captures the between-person variability in response of serum 25(OHD to vitamin D intake.

[Negative prognostic impact of female gender on oncological outcomes following radical cystectomy].

Science.gov (United States)

Dabi, Y; Rouscoff, Y; Delongchamps, N B; Sibony, M; Saighi, D; Zerbib, M; Peyraumore, M; Xylinas, E

2016-02-01

To confirm gender specific differences in pathologic factors and survival rates of urothelial bladder cancer patients treated with radical cystectomy. We conducted a retrospective monocentric study on 701 patients treated with radical cystectomy and pelvic lymphadenectomy for muscle invasive bladder cancer. Impact of gender on recurrence rate, specific and non-specific mortality rate were evaluated using Cox regression models in univariate and multivariate analysis. We collected data on 553 males (78.9%) and 148 females (21.1%) between 1998 and 2011. Both groups were comparable at inclusion regarding age, pathologic stage, nodal status and lymphovascular invasion. Mean follow-up time was 45 months (interquartile 23-73) and by that time, 163 patients (23.3%) had recurrence of their tumor and 127 (18.1%) died from their disease. In multivariable Cox regression analyses, female gender was independently associated with disease recurrence (RR: 1.73; 95% CI 1.22-2.47; P=0.02) and cancer-specific mortality (RR=2.50, 95% CI=1.71-3.68; P<0.001). We confirmed female gender to be an independent negative prognosis factor for patients following a radical cystectomy and lymphadenectomy for an invasive muscle bladder cancer. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Breast cancer risk in female survivors of Hodgkin's lymphoma

DEFF Research Database (Denmark)

De Bruin, Marie L; Sparidans, Judith; van't Veer, Mars B

2009-01-01

PURPOSE: We assessed the long-term risk of breast cancer (BC) after treatment for Hodgkin's lymphoma (HL). We focused on the volume of breast tissue exposed to radiation and the influence of gonadotoxic chemotherapy (CT). PATIENTS AND METHODS: We performed a cohort study among 1,122 female 5-year...... survivors treated for HL before the age of 51 years between 1965 and 1995. We compared the incidence of BC with that in the general population. To assess the risk according to radiation volume and hormone factors, we performed multivariate Cox regression analyses. RESULTS: After a median follow-up of 17...

Analysing inequalities in Germany a structured additive distributional regression approach

CERN Document Server

Silbersdorff, Alexander

2017-01-01

This book seeks new perspectives on the growing inequalities that our societies face, putting forward Structured Additive Distributional Regression as a means of statistical analysis that circumvents the common problem of analytical reduction to simple point estimators. This new approach allows the observed discrepancy between the individuals’ realities and the abstract representation of those realities to be explicitly taken into consideration using the arithmetic mean alone. In turn, the method is applied to the question of economic inequality in Germany.

Insight into the Female Longevity Puzzle: Using Register Data to Analyse Mortality and Cause of Death Behaviour Across Socio-economic Groups

DEFF Research Database (Denmark)

Kallestrup-Lamb, Malene; Rosenskjold, Carsten Paysen T.

This paper analyses the complexity of female longevity improvements. As socio-economic status influence health and mortality, we partition all individuals, at each age and year, into ten socio-economic groups based on an affluence measure. We identify the particular socio-economic groups that have...... for all subgroups, however with particular large decreases for the low-middle and middle affluence groups. We find that causes of deaths related to smoking partly contribute to the slowdown in female longevity. However the lack of improvements in deaths relating to ischemic heart diseases is dominant...

The relationship between attendance at birth and maternal mortality rates: an exploration of United Nations' data sets including the ratios of physicians and nurses to population, GNP per capita and female literacy.

Science.gov (United States)

Robinson, J J; Wharrad, H

2001-05-01

The relationship between attendance at birth and maternal mortality rates: an exploration of United Nations' data sets including the ratios of physicians and nurses to population, GNP per capita and female literacy. This is the third and final paper drawing on data taken from United Nations (UN) data sets. The first paper examined the global distribution of health professionals (as measured by ratios of physicians and nurses to population), and its relationship to gross national product per capita (GNP) (Wharrad & Robinson 1999). The second paper explored the relationships between the global distribution of physicians and nurses, GNP, female literacy and the health outcome indicators of infant and under five mortality rates (IMR and u5MR) (Robinson & Wharrad 2000). In the present paper, the global distribution of health professionals is explored in relation to maternal mortality rates (MMRs). The proportion of births attended by medical and nonmedical staff defined as "attendance at birth by trained personnel" (physicians, nurses, midwives or primary health care workers trained in midwifery skills), is included as an additional independent variable in the regression analyses, together with the ratio of physicians and nurses to population, female literacy and GNP. To extend our earlier analyses by considering the relationships between the global distribution of health professionals (ratios of physicians and nurses to population, and the proportion of births attended by trained health personnel), GNP, female literacy and MMR. countries, regression analyses were performed using numbers of physicians, and numbers of nurses, per 1000 population, the proportion of births attended by trained health personnel, GNP per capita and female literacy as independent variables and MMRs as the dependent variable. Linear regression analyses show positive associations for MMRs and the ratios of physicians to population (73%, n=136), ratios of nurses to population (56%, n=137), and

Occupational factors and reproductive outcomes among a cohort of female veterinarians.

Science.gov (United States)

Wilkins, J R; Steele, L L

1998-07-01

To estimate absolute and relative risks of preterm delivery (PTD) and small-for-gestational-age (SGA) births among a cohort of female veterinarians in relation to selected occupational factors, including clinical practice type (CPT). Retrospective cohort survey. 2,997 female graduates from US veterinary colleges between 1970 and 1980. Relevant health and occupational data were collected through a self-administered mail questionnaire with telephone follow-up of nonrespondents. Absolute and relative risks of PTD and SGA births were estimated in relation to maternal CPT at the time of conception and exposure to 13 occupational factors. Attempts were made to control confounding by use of multiple logistic regression analyses. Absolute and relative risks of PTD were highest for veterinarians employed in exclusively equine clinical practice. Although several increased, none of the CPT-specific relative risk estimates were significantly different from the null value of 1. Exposure-specific analyses indicated that occupational involvement with solvents among exclusively small animal practitioners was associated with the highest relative risk of PTD. A small number of SGA births limited information that could be obtained from these analyses. Overall absolute risks of PTD and SGA births among cohort members were much lower in comparison with the general female population. Given the large number of women currently practicing and entering the profession of veterinary medicine, clinical tasks associated with potential reproductive hazards should be approached with heightened awareness and increased caution, especially activities that may involve exposure to solvents.

The relationship between psychosocial maturity and assertiveness in males and females.

Science.gov (United States)

Goldman, J A; Olczak, P V

1981-02-01

The relationship between psychosocial maturity (psychological health) and assertiveness was investigated in a sample of United States college males and females. Results revealed a moderately high positive relationship between psychosocial maturity (PSM) and self-reported assertiveness on the Rathus and Galassi scales for both sexes. This relationship was slightly stronger (in terms of variance accounted for) for males than females, significant differences being obtained for Intimacy on the Rathus scale and PSM and Intimacy on the Galassi scale. Multiple regression analyses revealed that the personality components most consistently accounting for major portions of the variance in predicting male assertiveness scores on both the Rathus Assertiveness Schedule and the College Self-Expression Scale were Intimacy and Initiative, while in predicting female assertiveness, only Initiative was involved. The findings were related to previous research, recent work on the androgyny construct (instrumental vs. expressive behaviors), and exhortations for increased cooperation between schools of psychotherapy to establish it as a more unified discipline.

A Simulation Investigation of Principal Component Regression.

Science.gov (United States)

Allen, David E.

Regression analysis is one of the more common analytic tools used by researchers. However, multicollinearity between the predictor variables can cause problems in using the results of regression analyses. Problems associated with multicollinearity include entanglement of relative influences of variables due to reduced precision of estimation,…

FEMALE SOCIAL ENTREPRENEURSHIP AND SOCIO-CULTURAL CONTEXT: AN INTERNATIONAL ANALYSIS

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David Urbano Pulido

2014-12-01

Full Text Available In this article we analyse the socio-cultural factors that influence the likelihood of women becoming social entrepreneurs, using institutional economics. Binary logistic regression has been applied as the statistical method to test the hypotheses proposed, using data (40 countries and 56,875 individuals from the World Value Survey (WVS and the World Bank (WB. The main findings of the study reaffirm the relevance of socio-cultural factors to social entrepreneurship. Particularly, we have found that altruistic attitudes and being a member of a social organization are the most relevant socio-cultural factors for social female entrepreneurship.

Check-all-that-apply data analysed by Partial Least Squares regression

DEFF Research Database (Denmark)

Rinnan, Åsmund; Giacalone, Davide; Frøst, Michael Bom

2015-01-01

are analysed by multivariate techniques. CATA data can be analysed both by setting the CATA as the X and the Y. The former is the PLS-Discriminant Analysis (PLS-DA) version, while the latter is the ANOVA-PLS (A-PLS) version. We investigated the difference between these two approaches, concluding...

Female Directors on Corporate Boards: Does Female Leadership Drive Corporate Environmental Transparency?

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Phua Michelle Siew Huei

2017-01-01

Full Text Available This paper examines the role of female directors on corporate boardroom on the extent of corporate environmental disclosure (CED of 260 Malaysian listed companies in year 2013. Resource dependence theory is utilized as the theoretical framework to explain the role of female directors on corporate boards. Content analysis is employed to gauge the extent of CED based on a self-constructed index that is derived from Global Reporting Initiatives (GRI and prior studies. Multiple regression is conducted and findings revealed that female directors– presence and female holding multiple directorships to be significant predictors of extent of CED. The findings lend support to the resource dependence theory on the contribution of board gender diversity and are useful for both policy makers and regulators.

Love, Trust, and HIV Risk Among Female Sex Workers and Their Intimate Male Partners.

Science.gov (United States)

Syvertsen, Jennifer L; Bazzi, Angela Robertson; Martinez, Gustavo; Rangel, M Gudelia; Ulibarri, Monica D; Fergus, Kirkpatrick B; Amaro, Hortensia; Strathdee, Steffanie A

2015-08-01

We examined correlates of love and trust among female sex workers and their noncommercial male partners along the Mexico-US border. From 2011 to 2012, 322 partners in Tijuana and Ciudad Juárez, Mexico, completed assessments of love and trust. Cross-sectional dyadic regression analyses identified associations of relationship characteristics and HIV risk behaviors with love and trust. Within 161 couples, love and trust scores were moderately high (median 70/95 and 29/40 points, respectively) and correlated with relationship satisfaction. In regression analyses of HIV risk factors, men and women who used methamphetamine reported lower love scores, whereas women who used heroin reported slightly higher love. In an alternate model, men with concurrent sexual partners had lower love scores. For both partners, relationship conflict was associated with lower trust. Love and trust are associated with relationship quality, sexual risk, and drug use patterns that shape intimate partners' HIV risk. HIV interventions should consider the emotional quality of sex workers' intimate relationships.

The Use of Nonparametric Kernel Regression Methods in Econometric Production Analysis

DEFF Research Database (Denmark)

Czekaj, Tomasz Gerard

and nonparametric estimations of production functions in order to evaluate the optimal firm size. The second paper discusses the use of parametric and nonparametric regression methods to estimate panel data regression models. The third paper analyses production risk, price uncertainty, and farmers' risk preferences...... within a nonparametric panel data regression framework. The fourth paper analyses the technical efficiency of dairy farms with environmental output using nonparametric kernel regression in a semiparametric stochastic frontier analysis. The results provided in this PhD thesis show that nonparametric......This PhD thesis addresses one of the fundamental problems in applied econometric analysis, namely the econometric estimation of regression functions. The conventional approach to regression analysis is the parametric approach, which requires the researcher to specify the form of the regression...

Detecting overdispersion in count data: A zero-inflated Poisson regression analysis

Science.gov (United States)

Afiqah Muhamad Jamil, Siti; Asrul Affendi Abdullah, M.; Kek, Sie Long; Nor, Maria Elena; Mohamed, Maryati; Ismail, Norradihah

2017-09-01

This study focusing on analysing count data of butterflies communities in Jasin, Melaka. In analysing count dependent variable, the Poisson regression model has been known as a benchmark model for regression analysis. Continuing from the previous literature that used Poisson regression analysis, this study comprising the used of zero-inflated Poisson (ZIP) regression analysis to gain acute precision on analysing the count data of butterfly communities in Jasin, Melaka. On the other hands, Poisson regression should be abandoned in the favour of count data models, which are capable of taking into account the extra zeros explicitly. By far, one of the most popular models include ZIP regression model. The data of butterfly communities which had been called as the number of subjects in this study had been taken in Jasin, Melaka and consisted of 131 number of subjects visits Jasin, Melaka. Since the researchers are considering the number of subjects, this data set consists of five families of butterfly and represent the five variables involve in the analysis which are the types of subjects. Besides, the analysis of ZIP used the SAS procedure of overdispersion in analysing zeros value and the main purpose of continuing the previous study is to compare which models would be better than when exists zero values for the observation of the count data. The analysis used AIC, BIC and Voung test of 5% level significance in order to achieve the objectives. The finding indicates that there is a presence of over-dispersion in analysing zero value. The ZIP regression model is better than Poisson regression model when zero values exist.

[Nickel levels in female dermatological patients].

Science.gov (United States)

Schwegler, U; Twardella, D; Fedorov, M; Darsow, U; Schaller, K-H; Habernegg, R; Behrendt, H; Fromme, H

2009-07-01

Nickel levels in urine were determined among 163 female dermatological patients aged 18 to 46 years. Data on life-style factors were collected in parallel via a questionnaire. Urinary nickel excretion was in the normal range of the German female population (0.2-46.1 microg Ni/g creatinine). The 95th percentile (3.9 microg Ni/l urine) exceeded the German reference value (3.0 microg Ni/l urine). In the multivariate regression analyses we found a statistically significant increase of ln-transformed nickel levels with increase in age and in women using dietary supplements. The following variables were not associated with Nickel urine levels: suffering from nickel eczema, smoking, drinking stagnated water, eating foods with high nickel contents and using nickel-containing kitchen utensils as, for example, an electric kettle with an open heater coil. We conclude that personal urinary levels should be assessed with simultaneous consideration of habits and life-style factors. A German national survery would be useful. Those patients who experience the exacerbation of their eczema in cases of oral provocation, for example, by a high nickel diet should be aware of potential sources of nickel, such as supplements.

Alpins and thibos vectorial astigmatism analyses: proposal of a linear regression model between methods

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Giuliano de Oliveira Freitas

2013-10-01

Full Text Available PURPOSE: To determine linear regression models between Alpins descriptive indices and Thibos astigmatic power vectors (APV, assessing the validity and strength of such correlations. METHODS: This case series prospectively assessed 62 eyes of 31 consecutive cataract patients with preoperative corneal astigmatism between 0.75 and 2.50 diopters in both eyes. Patients were randomly assorted among two phacoemulsification groups: one assigned to receive AcrySof®Toric intraocular lens (IOL in both eyes and another assigned to have AcrySof Natural IOL associated with limbal relaxing incisions, also in both eyes. All patients were reevaluated postoperatively at 6 months, when refractive astigmatism analysis was performed using both Alpins and Thibos methods. The ratio between Thibos postoperative APV and preoperative APV (APVratio and its linear regression to Alpins percentage of success of astigmatic surgery, percentage of astigmatism corrected and percentage of astigmatism reduction at the intended axis were assessed. RESULTS: Significant negative correlation between the ratio of post- and preoperative Thibos APVratio and Alpins percentage of success (%Success was found (Spearman's ρ=-0.93; linear regression is given by the following equation: %Success = (-APVratio + 1.00x100. CONCLUSION: The linear regression we found between APVratio and %Success permits a validated mathematical inference concerning the overall success of astigmatic surgery.

Male and Female Perception of Physical Attractiveness

Directory of Open Access Journals (Sweden)

Ray Garza

2016-02-01

Full Text Available Waist-to-hip ratio (WHR and breast size are morphological traits that are associated with female attractiveness. Previous studies using line drawings of women have shown that men across cultures rate low WHRs (0.6 and 0.7 as most attractive. In this study, we used additional viewing measurements (i.e., first fixation duration and visual regressions to measure visual attention and record how long participants first focused on the female body and whether they regressed back to an area of interest. Additionally, we manipulated skin tone to determine whether they preferred light- or dark-skinned women. In two eye tracking experiments, participants rated the attractiveness of female nude images varying in WHR (0.5–0.9, breast size, and skin tone. We measured first fixation duration, gaze duration, and total time. The overall results of both studies revealed that visual attention fell mostly on the face, the breasts, and the midriff of the female body, supporting the evolutionary view that reproductively relevant regions of the female body are important to female attractiveness. Because the stimuli varied in skin tone and the participants were mainly Hispanic of Mexican American descent, the findings from these studies also support a preference for low WHRs and reproductively relevant regions of the female body.

Linear regression metamodeling as a tool to summarize and present simulation model results.

Science.gov (United States)

Jalal, Hawre; Dowd, Bryan; Sainfort, François; Kuntz, Karen M

2013-10-01

Modelers lack a tool to systematically and clearly present complex model results, including those from sensitivity analyses. The objective was to propose linear regression metamodeling as a tool to increase transparency of decision analytic models and better communicate their results. We used a simplified cancer cure model to demonstrate our approach. The model computed the lifetime cost and benefit of 3 treatment options for cancer patients. We simulated 10,000 cohorts in a probabilistic sensitivity analysis (PSA) and regressed the model outcomes on the standardized input parameter values in a set of regression analyses. We used the regression coefficients to describe measures of sensitivity analyses, including threshold and parameter sensitivity analyses. We also compared the results of the PSA to deterministic full-factorial and one-factor-at-a-time designs. The regression intercept represented the estimated base-case outcome, and the other coefficients described the relative parameter uncertainty in the model. We defined simple relationships that compute the average and incremental net benefit of each intervention. Metamodeling produced outputs similar to traditional deterministic 1-way or 2-way sensitivity analyses but was more reliable since it used all parameter values. Linear regression metamodeling is a simple, yet powerful, tool that can assist modelers in communicating model characteristics and sensitivity analyses.

Z linkage of female promiscuity genes in the moth Utetheisa ornatrix: support for the sexy-sperm hypothesis?

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Iyengar, Vikram K; Reeve, Hudson K

2010-05-01

Female preference genes for large males in the highly promiscuous moth Utetheisa ornatrix (Lepidoptera: Arctiidae) have previously been shown to be mostly Z-linked, in accordance with the hypothesis that ZZ-ZW sex chromosome systems should facilitate Fisherian sexual selection. We determined the heritability of both female and male promiscuity in the highly promiscuous moth U. ornatrix (Lepidoptera: Arctiidae) through parent-offspring and grandparent-offspring regression analyses. Our data show that male promiscuity is not sex-limited and either autosomal or sex-linked whereas female promiscuity is primarily determined by sex-limited, Z-linked genes. These data are consistent with the "sexy-sperm hypothesis," which posits that multiple-mating and sperm competitiveness coevolve through a Fisherian-like process in which female promiscuity is a kind of mate choice in which sperm-competitiveness is the trait favored in males. Such a Fisherian process should also be more potent when female preferences are Z-linked and sex-limited than when autosomal or not limited.

Impact of military trauma exposures on posttraumatic stress and depression in female veterans.

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Goldstein, Lizabeth A; Dinh, Julie; Donalson, Rosemary; Hebenstreit, Claire L; Maguen, Shira

2017-03-01

Previous research has demonstrated the deleterious effects of traumatic military experiences on symptoms of posttraumatic stress disorder (PTSD) and depression in female veterans. However, more research is needed to identify the unique predictors of distressing psychological symptoms when both combat-related and sexual trauma are considered, particularly as women's combat exposure in the military increases. Female veterans who had attended at least one appointment at a large Veterans Health Administration medical center were invited to complete questionnaires about traumatic military exposures and psychiatric symptoms. A total of 403 veterans responded, with 383 respondents' data used in analyses. Multiple regression analyses were conducted with trauma exposure items entered simultaneously to determine their association with symptoms of (1) PTSD and (2) depression. Sexual assault had the strongest relationship with both posttraumatic and depressive symptoms. Sexual assault, sexual harassment, feeling in danger of being killed, and seeing others killed/injured were associated with symptoms of PTSD, but only sexual assault and sexual harassment were associated with symptoms of depression, even when accounting for several aspects of combat exposure. Improving assessment for trauma exposure and developing treatments personalized to type of trauma experienced are important clinical research priorities as female service members' roles in the military expand. Published by Elsevier B.V.

Predictors of insubordinate aggression among captive female rhesus macaques.

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Seil, Shannon K; Hannibal, Darcy L; Beisner, Brianne A; McCowan, Brenda

2017-11-01

Cercopithicine primates tend to have nepotistic hierarchies characterized by predictable, kinship-based dominance. Although aggression is typically directed down the hierarchy, insubordinate aggression does occur. Insubordination is important to understand because it can precipitate social upheaval and undermine group stability; however, the factors underlying it are not well understood. We test whether key social and demographic variables predict insubordination among captive female rhesus macaques. To identify factors influencing insubordination, multivariate analyses of 10,821 dyadic conflicts among rhesus macaque females were conducted, using data from six captive groups. A segmented regression analysis was used to identify dyads with insubordination. Negative binomial regression analyses and an information theoretic approach were used to assess predictors of insubordination among dyads. In the best models, weight difference (w = 1.0; IRR = 0.930), age (dominant: w = 1.0, IRR = 0.681; subordinate: w = 1.0, IRR = 1.069), the subordinate's total number of allies (w = 0.727, IRR = 1.060) or non-kin allies (w = 0.273, IRR = 1.165), the interaction of the dominant's kin allies and weight difference (w = 0.938, IRR = 1.046), violation of youngest ascendancy (w = 1.0; IRR = 2.727), and the subordinate's maternal support (w = 1.0; IRR = 2.928), are important predictors of insubordination. These results show that both intrinsic and social factors influence insubordinate behavior. This adds to evidence of the importance of intrinsic factors and flexibility in a social structure thought to be rigid and predetermined by external factors. Further, because insubordination can precipitate social overthrow, determining predictors of insubordination will shed light on mechanisms underlying stability in nepotistic societies. © 2017 Wiley Periodicals, Inc.

Prevalence and correlates of sexual risk among male and female sex workers in Tijuana, Mexico.

Science.gov (United States)

Katsulis, Yasmina; Durfee, Alesha

2012-01-01

We investigated prevalence and correlates of sexual risk behaviours among male and female sex workers in Tijuana, Mexico, the busiest border crossing area on the US - Mexico border, analysing survey data from a purposive, cross-sectional sample of male and female sex workers who worked in a range of indoor and outdoor settings. Logistic regression was used to determine factors that were associated with sexual risk-taking, defined as failing to use a condom with last client. In bivariate regression models, gender, work setting (e.g., indoor vs. outdoor), poverty, engaging in survival sex, marital status and perceived drug addiction were correlated with sexual risk. When controlling for work location, housing insecurity, poverty, survival sex, marital status and perceived drug addiction, male sex workers were still 10 times more likely than female sex workers (FSW) to engage in sex without a condom during their last encounter with a client. And, although FSW were significantly more likely than males to have used a condom with a client, they were significantly less likely than males to have used a condom with their regular partner. Future research should further examine how gender shapes sexual risk activities in both commercial and non-commercial relationships.

Assessing the suitability of summary data for two-sample Mendelian randomization analyses using MR-Egger regression: the role of the I2 statistic.

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Bowden, Jack; Del Greco M, Fabiola; Minelli, Cosetta; Davey Smith, George; Sheehan, Nuala A; Thompson, John R

2016-12-01

: MR-Egger regression has recently been proposed as a method for Mendelian randomization (MR) analyses incorporating summary data estimates of causal effect from multiple individual variants, which is robust to invalid instruments. It can be used to test for directional pleiotropy and provides an estimate of the causal effect adjusted for its presence. MR-Egger regression provides a useful additional sensitivity analysis to the standard inverse variance weighted (IVW) approach that assumes all variants are valid instruments. Both methods use weights that consider the single nucleotide polymorphism (SNP)-exposure associations to be known, rather than estimated. We call this the `NO Measurement Error' (NOME) assumption. Causal effect estimates from the IVW approach exhibit weak instrument bias whenever the genetic variants utilized violate the NOME assumption, which can be reliably measured using the F-statistic. The effect of NOME violation on MR-Egger regression has yet to be studied. An adaptation of the I2 statistic from the field of meta-analysis is proposed to quantify the strength of NOME violation for MR-Egger. It lies between 0 and 1, and indicates the expected relative bias (or dilution) of the MR-Egger causal estimate in the two-sample MR context. We call it IGX2 . The method of simulation extrapolation is also explored to counteract the dilution. Their joint utility is evaluated using simulated data and applied to a real MR example. In simulated two-sample MR analyses we show that, when a causal effect exists, the MR-Egger estimate of causal effect is biased towards the null when NOME is violated, and the stronger the violation (as indicated by lower values of IGX2 ), the stronger the dilution. When additionally all genetic variants are valid instruments, the type I error rate of the MR-Egger test for pleiotropy is inflated and the causal effect underestimated. Simulation extrapolation is shown to substantially mitigate these adverse effects. We

The more total cognitive load is reduced by cues, the better retention and transfer of multimedia learning: A meta-analysis and two meta-regression analyses.

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Xie, Heping; Wang, Fuxing; Hao, Yanbin; Chen, Jiaxue; An, Jing; Wang, Yuxin; Liu, Huashan

2017-01-01

Cueing facilitates retention and transfer of multimedia learning. From the perspective of cognitive load theory (CLT), cueing has a positive effect on learning outcomes because of the reduction in total cognitive load and avoidance of cognitive overload. However, this has not been systematically evaluated. Moreover, what remains ambiguous is the direct relationship between the cue-related cognitive load and learning outcomes. A meta-analysis and two subsequent meta-regression analyses were conducted to explore these issues. Subjective total cognitive load (SCL) and scores on a retention test and transfer test were selected as dependent variables. Through a systematic literature search, 32 eligible articles encompassing 3,597 participants were included in the SCL-related meta-analysis. Among them, 25 articles containing 2,910 participants were included in the retention-related meta-analysis and the following retention-related meta-regression, while there were 29 articles containing 3,204 participants included in the transfer-related meta-analysis and the transfer-related meta-regression. The meta-analysis revealed a statistically significant cueing effect on subjective ratings of cognitive load (d = -0.11, 95% CI = [-0.19, -0.02], p < 0.05), retention performance (d = 0.27, 95% CI = [0.08, 0.46], p < 0.01), and transfer performance (d = 0.34, 95% CI = [0.12, 0.56], p < 0.01). The subsequent meta-regression analyses showed that dSCL for cueing significantly predicted dretention for cueing (β = -0.70, 95% CI = [-1.02, -0.38], p < 0.001), as well as dtransfer for cueing (β = -0.60, 95% CI = [-0.92, -0.28], p < 0.001). Thus in line with CLT, adding cues in multimedia materials can indeed reduce SCL and promote learning outcomes, and the more SCL is reduced by cues, the better retention and transfer of multimedia learning.

Adverse reproductive outcomes among female veterinarians

International Nuclear Information System (INIS)

Schenker, M.B.; Samuels, S.J.; Green, R.S.; Wiggins, P.

1990-01-01

Because female veterinarians are exposed to several known reproductive hazards, the authors conducted a reproductive survey of all female graduates of a US veterinary school (n = 537) and law school (comparison group, n = 794). Analysis was confined to pregnancies completed after the second year of professional school and from 1966 to 1986. Based on one randomly chosen eligible pregnancy per woman (veterinarians, n = 176; lawyers, n = 229), spontaneous abortion rates, adjusted for elective abortions, were 13.3% for the veterinarians and 15.1% for the lawyers; these did not differ significantly. A Cox life table regression model controlling for age, smoking, alcohol use, and prior spontaneous abortion also showed no significant difference in spontaneous abortion rates between the two populations. Using all pregnancies, veterinarians who reported performing five or more radiographic examinations per week had a marginally elevated risk of spontaneous abortion, but the statistical significance disappeared when analysis was limited to one random pregnancy per woman. For one random eligible birth per woman, the mean birth weight did not differ significantly between the veterinarians and lawyers, even after controlling for possible confounders in regression analyses. A higher rate of reportable birth defects was observed among the veterinarians than among the lawyers (relative risk = 4.2, 95% confidence interval 1.2-15.1), but this unexpected result must be considered hypothesis-generating. The authors did not find an overall increased risk for spontaneous abortion or low birth weight infants among veterinarians compared with lawyers, but veterinarians who reported performing five or more radiographic examinations per week may have been at increased risk for spontaneous abortion

Predicting Word Reading Ability: A Quantile Regression Study

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McIlraith, Autumn L.

2018-01-01

Predictors of early word reading are well established. However, it is unclear if these predictors hold for readers across a range of word reading abilities. This study used quantile regression to investigate predictive relationships at different points in the distribution of word reading. Quantile regression analyses used preschool and…

Structural vascular disease in Africans: performance of ethnic-specific waist circumference cut points using logistic regression and neural network analyses: the SABPA study

OpenAIRE

Botha, J.; De Ridder, J.H.; Potgieter, J.C.; Steyn, H.S.; Malan, L.

2013-01-01

A recently proposed model for waist circumference cut points (RPWC), driven by increased blood pressure, was demonstrated in an African population. We therefore aimed to validate the RPWC by comparing the RPWC and the Joint Statement Consensus (JSC) models via Logistic Regression (LR) and Neural Networks (NN) analyses. Urban African gender groups (N=171) were stratified according to the JSC and RPWC cut point models. Ultrasound carotid intima media thickness (CIMT), blood pressure (BP) and fa...

Cancer burden trends in Umbria region using a joinpoint regression

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Giuseppe Michele Masanotti

2015-09-01

Full Text Available INTRODUCTION. The analysis of the epidemiological data on cancer is an important tool to control and evaluate the outcomes of primary and secondary prevention, the effectiveness of health care and, in general, all cancer control activities. MATERIALS AND METHODS. The aim of the this paper is to analyze the cancer mortality in the Umbria region from 1978 to 2009 and incidence from 1994-2008. Sex and site-specific trends for standardized rates were analyzed by "joinpoint regression", using the surveillance epidemiology and end results (SEER software. RESULTS. Applying the jointpoint analyses by sex and cancer site, to incidence spanning from 1994 to 2008 and mortality from 1978 to 2009 for all sites, both in males and females, a significant joinpoint for mortality was found; moreover the trend shape was similar and the joinpoint years were very close. In males standardized rate significantly increased up to 1989 by 1.23% per year and significantly decreased thereafter by -1.31%; among females the mortality rate increased in average of 0.78% (not significant per year till 1988 and afterward significantly decreased by -0.92% per year. Incidence rate showed different trends among sexes. In males was practically constant over the period studied (not significant increase 0.14% per year, in females significantly increased by 1.49% per year up to 2001 and afterward slowly decreased (-0.71% n.s. estimated annual percent change − EAPC. CONCLUSIONS. For all sites combined trends for mortality decreased since late '80s, both in males and females; such behaviour is in line with national and European Union data. This work shows that, even compared to health systems that invest more resources, the Umbria public health system achieved good health outcomes.

Female married illiteracy as the most important continual determinant of total fertility rate among districts of Empowered Action Group States of India: Evidence from Annual Health Survey 2011-12.

Science.gov (United States)

Kumar, Rajesh; Dogra, Vishal; Rani, Khushbu; Sahu, Kanti

2017-01-01

District level determinants of total fertility rate in Empowered Action Group states of India can help in ongoing population stabilization programs in India. Present study intends to assess the role of district level determinants in predicting total fertility rate among districts of the Empowered Action Group states of India. Data from Annual Health Survey (2011-12) was analysed using STATA and R software packages. Multiple linear regression models were built and evaluated using Akaike Information Criterion. For further understanding, recursive partitioning was used to prepare a regression tree. Female married illiteracy positively associated with total fertility rate and explained more than half (53%) of variance. Under multiple linear regression model, married illiteracy, infant mortality rate, Ante natal care registration, household size, median age of live birth and sex ratio explained 70% of total variance in total fertility rate. In regression tree, female married illiteracy was the root node and splits at 42% determined TFR illiteracy with splits at 23% to determine TFR illiteracy is one of the most important determinants explaining total fertility rate among the districts of an Empowered Action Group states. Focus on female literacy is required to stabilize the population growth in long run.

Female terrorism : a review

NARCIS (Netherlands)

Jacques, Karen; Taylor, Paul J.

2009-01-01

The sharp growth in the number of publications examining female involvement in terrorism has produced a valuable but un-integrated body of knowledge spread across many disciplines. In this paper, we bring together 54 publications on female terrorism and use qualitative and quantitative analyses to

Evaluation of Female Breast Cancer Risk Among the Betel Quid Chewer: A Bio-Statistical Assessment in Assam, India.

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Rajbongshi, Nijara; Mahanta, Lipi B; Nath, Dilip C

2015-06-01

Breast cancer is the most commonly diagnosed cancer among the female population of Assam, India. Chewing of betel quid with or without tobacco is common practice among female population of this region. Moreoverthe method of preparing the betel quid is different from other parts of the country.So matched case control study is conducted to analyse whetherbetel quid chewing plays a significant role in the high incidence of breast cancer occurrences in Assam. Here, controls are matched to the cases by age at diagnosis (±5 years), family income and place of residence with matching ratio 1:1. Conditional logistic regression models and odd ratios (OR) was used to draw conclusions. It is observed that cases are more habituated to chewing habits than the controls.Further the conditional logistic regression analysis reveals that betel quid chewer faces 2.353 times more risk having breast cancer than the non-chewer with p value 0.0003 (95% CI 1.334-4.150). Though the female population in Assam usually does not smoke, the addictive habits typical to this region have equal effect on the occurrence of breast cancer.

[Prevalence and associated factors of female urinary incontinence in Hebei province].

Science.gov (United States)

Jiang, Y; Yan, L; Du, F D; Zheng, P T; Zhang, L; Jiang, L; Huang, X H

2016-12-25

Objective: To estimate the prevalence and associated factors of adult female urinary incontinence in Hebei province. Methods: Stratified and multistage sampling method was used, between January 2016 to May 2016, to investigate the target population in Hebei province. While, logistic regression was used to analyse datas. Results: A population-based survey was conducted in 2 450 women in Hebei province, there were 2 408 effective questionnaires after deleting 48 invalid questionnaires. According to the results, the average age of subjects was (56±15) years old, and the urinary incontinence prevalence of adult female in Hebei province was 27.70% (667/2 408). Stress urinary incontinence, urge urinary incontinence and mixed urinary incontinence were diagnosed as 23.13% (557/2 408), 1.58% (38/2 408) and 2.99% (72/2 408), respectively. There were only 2.85% (19/667) urinary incontinence patients seeking medical help. The results of logistic regression analysis showed that age, daily water intake, pulmonary diseases, urinary tract infection, hypertension, chronic low back pain, dysmenorrhea, vaginitis, abortion, mode of delivery, postpartum infection were statistically significant (all P ≤0.05). Among these factors, cesarean section was the protective factor for urinary incontinence ( OR= 0.365, 95 % CI: 0.195-0.685, P urinary incontinence in adult female in Hebei province is high, and there are few patients seeking medical help. It is a common disorder in women and is associated with many factors; among these factors, cesarean section is the protective factor for urinary incontinence.

Human immunodeficiency viruses appear compartmentalized to the female genital tract in cross-sectional analyses but genital lineages do not persist over time.

Science.gov (United States)

Bull, Marta E; Heath, Laura M; McKernan-Mullin, Jennifer L; Kraft, Kelli M; Acevedo, Luis; Hitti, Jane E; Cohn, Susan E; Tapia, Kenneth A; Holte, Sarah E; Dragavon, Joan A; Coombs, Robert W; Mullins, James I; Frenkel, Lisa M

2013-04-15

Whether unique human immunodeficiency type 1 (HIV) genotypes occur in the genital tract is important for vaccine development and management of drug resistant viruses. Multiple cross-sectional studies suggest HIV is compartmentalized within the female genital tract. We hypothesize that bursts of HIV replication and/or proliferation of infected cells captured in cross-sectional analyses drive compartmentalization but over time genital-specific viral lineages do not form; rather viruses mix between genital tract and blood. Eight women with ongoing HIV replication were studied during a period of 1.5 to 4.5 years. Multiple viral sequences were derived by single-genome amplification of the HIV C2-V5 region of env from genital secretions and blood plasma. Maximum likelihood phylogenies were evaluated for compartmentalization using 4 statistical tests. In cross-sectional analyses compartmentalization of genital from blood viruses was detected in three of eight women by all tests; this was associated with tissue specific clades containing multiple monotypic sequences. In longitudinal analysis, the tissues-specific clades did not persist to form viral lineages. Rather, across women, HIV lineages were comprised of both genital tract and blood sequences. The observation of genital-specific HIV clades only in cross-sectional analysis and an absence of genital-specific lineages in longitudinal analyses suggest a dynamic interchange of HIV variants between the female genital tract and blood.

Classification and regression tree (CART) analyses of genomic signatures reveal sets of tetramers that discriminate temperature optima of archaea and bacteria

Science.gov (United States)

Dyer, Betsey D.; Kahn, Michael J.; LeBlanc, Mark D.

2008-01-01

Classification and regression tree (CART) analysis was applied to genome-wide tetranucleotide frequencies (genomic signatures) of 195 archaea and bacteria. Although genomic signatures have typically been used to classify evolutionary divergence, in this study, convergent evolution was the focus. Temperature optima for most of the organisms examined could be distinguished by CART analyses of tetranucleotide frequencies. This suggests that pervasive (nonlinear) qualities of genomes may reflect certain environmental conditions (such as temperature) in which those genomes evolved. The predominant use of GAGA and AGGA as the discriminating tetramers in CART models suggests that purine-loading and codon biases of thermophiles may explain some of the results. PMID:19054742

Poisson regression for modeling count and frequency outcomes in trauma research.

Science.gov (United States)

Gagnon, David R; Doron-LaMarca, Susan; Bell, Margret; O'Farrell, Timothy J; Taft, Casey T

2008-10-01

The authors describe how the Poisson regression method for analyzing count or frequency outcome variables can be applied in trauma studies. The outcome of interest in trauma research may represent a count of the number of incidents of behavior occurring in a given time interval, such as acts of physical aggression or substance abuse. Traditional linear regression approaches assume a normally distributed outcome variable with equal variances over the range of predictor variables, and may not be optimal for modeling count outcomes. An application of Poisson regression is presented using data from a study of intimate partner aggression among male patients in an alcohol treatment program and their female partners. Results of Poisson regression and linear regression models are compared.

Publicizing female athletes' weights: implications for female psychology undergraduates acting as spectators.

Science.gov (United States)

Holm-Denoma, Jill; Smith, April; Waesche, Matthew

2014-09-01

The purpose of this study was to examine the effects of including female athletes' weights in athletic event programs on female spectators' body image, eating disorder symptoms, self-esteem, and affective state and to investigate whether the magnitude of the athletes' reported weights had differential effects on female spectators (i.e., do female spectators who view heavier athletes respond differently than those who view less heavy athletes?). We used an experimental design to examine hypotheses derived from competing theories to determine whether exposure to female athletes of varying weight would adversely or beneficially impact female undergraduates (N = 152) who served as athletic event spectators. Analyses indicated that in this simulated study, female spectators' body image, eating disorder symptoms, self-esteem, and affective states were not impacted by the presence or by the magnitude of female athletes' weights in athletic event programs. The results imply that including athletes' weights in game-day programs at women's athletic events does not affect female spectators on an individual level.

Cholecystokinin in plasma predicts cardiovascular mortality in elderly females

DEFF Research Database (Denmark)

Gøtze, Jens P.; Rehfeld, Jens F; Alehagen, Urban

2016-01-01

BACKGROUND: Cholecystokinin (CCK) and gastrin are related gastrointestinal hormones with documented cardiovascular effects of exogenous administration. It is unknown whether measurement of endogenous CCK or gastrin in plasma contains information regarding cardiovascular mortality. METHODS......: Mortality risk was evaluated using Cox proportional hazard regression and Kaplan-Meier analyses. Elderly patients in a primary care setting with symptoms of cardiac disease, i.e. shortness of breath, peripheral edema, and/or fatigue, were evaluated (n=470). Primary care patients were followed for 13years...... information was obtained from 4th quartile gastrin concentrations on 5-year cardiovascular mortality risk. CONCLUSIONS: CCK in plasma is an independent marker of cardiovascular mortality in elderly female patients. The study thus introduces measurement of plasma CCK in gender-specific cardiovascular risk...

Female married illiteracy as the most important continual determinant of total fertility rate among districts of Empowered Action Group States of India: Evidence from Annual Health Survey 2011–12

Directory of Open Access Journals (Sweden)

Rajesh Kumar

2017-01-01

Full Text Available Background: District level determinants of total fertility rate in Empowered Action Group states of India can help in ongoing population stabilization programs in India. Objective: Present study intends to assess the role of district level determinants in predicting total fertility rate among districts of the Empowered Action Group states of India. Material and Methods: Data from Annual Health Survey (2011-12 was analysed using STATA and R software packages. Multiple linear regression models were built and evaluated using Akaike Information Criterion. For further understanding, recursive partitioning was used to prepare a regression tree. Results: Female married illiteracy positively associated with total fertility rate and explained more than half (53% of variance. Under multiple linear regression model, married illiteracy, infant mortality rate, Ante natal care registration, household size, median age of live birth and sex ratio explained 70% of total variance in total fertility rate. In regression tree, female married illiteracy was the root node and splits at 42% determined TFR = 2.7. The next left side branch was again married illiteracy with splits at 23% to determine TFR = 2.1. Conclusion: We conclude that female married illiteracy is one of the most important determinants explaining total fertility rate among the districts of an Empowered Action Group states. Focus on female literacy is required to stabilize the population growth in long run.

Female children with incarcerated adult family members at risk for lifelong neurological decline.

Science.gov (United States)

Brewer-Smyth, Kathleen; Pohlig, Ryan T; Bucurescu, Gabriel

2016-07-01

A secondary analysis of data from adult female prison inmates in the mid-Atlantic United States defined relationships between having incarcerated adult family members during childhood and neurological outcomes. Of 135 inmates, 99 (60%) had one or more incarcerated adult family members during childhood. Regression analyses revealed that having incarcerated adult family members was related to greater frequency and severity of childhood abuse and higher incidence of neurological deficits in adulthood, especially related to traumatic brain injuries, compared to those without incarcerated adult family members. Along with being role models, adult family members impact the neurological health of children throughout their life-span.

Testing Mediation Using Multiple Regression and Structural Equation Modeling Analyses in Secondary Data

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Li, Spencer D.

2011-01-01

Mediation analysis in child and adolescent development research is possible using large secondary data sets. This article provides an overview of two statistical methods commonly used to test mediated effects in secondary analysis: multiple regression and structural equation modeling (SEM). Two empirical studies are presented to illustrate the…

Improving validation methods for molecular diagnostics: application of Bland-Altman, Deming and simple linear regression analyses in assay comparison and evaluation for next-generation sequencing.

Science.gov (United States)

Misyura, Maksym; Sukhai, Mahadeo A; Kulasignam, Vathany; Zhang, Tong; Kamel-Reid, Suzanne; Stockley, Tracy L

2018-02-01

A standard approach in test evaluation is to compare results of the assay in validation to results from previously validated methods. For quantitative molecular diagnostic assays, comparison of test values is often performed using simple linear regression and the coefficient of determination (R 2 ), using R 2 as the primary metric of assay agreement. However, the use of R 2 alone does not adequately quantify constant or proportional errors required for optimal test evaluation. More extensive statistical approaches, such as Bland-Altman and expanded interpretation of linear regression methods, can be used to more thoroughly compare data from quantitative molecular assays. We present the application of Bland-Altman and linear regression statistical methods to evaluate quantitative outputs from next-generation sequencing assays (NGS). NGS-derived data sets from assay validation experiments were used to demonstrate the utility of the statistical methods. Both Bland-Altman and linear regression were able to detect the presence and magnitude of constant and proportional error in quantitative values of NGS data. Deming linear regression was used in the context of assay comparison studies, while simple linear regression was used to analyse serial dilution data. Bland-Altman statistical approach was also adapted to quantify assay accuracy, including constant and proportional errors, and precision where theoretical and empirical values were known. The complementary application of the statistical methods described in this manuscript enables more extensive evaluation of performance characteristics of quantitative molecular assays, prior to implementation in the clinical molecular laboratory. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Augmenting Data with Published Results in Bayesian Linear Regression

Science.gov (United States)

de Leeuw, Christiaan; Klugkist, Irene

2012-01-01

In most research, linear regression analyses are performed without taking into account published results (i.e., reported summary statistics) of similar previous studies. Although the prior density in Bayesian linear regression could accommodate such prior knowledge, formal models for doing so are absent from the literature. The goal of this…

Human Immunodeficiency Viruses Appear Compartmentalized to the Female Genital Tract in Cross-Sectional Analyses but Genital Lineages Do Not Persist Over Time

Science.gov (United States)

Bull, Marta E.; Heath, Laura M.; McKernan-Mullin, Jennifer L.; Kraft, Kelli M.; Acevedo, Luis; Hitti, Jane E.; Cohn, Susan E.; Tapia, Kenneth A.; Holte, Sarah E.; Dragavon, Joan A.; Coombs, Robert W.; Mullins, James I.; Frenkel, Lisa M.

2013-01-01

Background. Whether unique human immunodeficiency type 1 (HIV) genotypes occur in the genital tract is important for vaccine development and management of drug resistant viruses. Multiple cross-sectional studies suggest HIV is compartmentalized within the female genital tract. We hypothesize that bursts of HIV replication and/or proliferation of infected cells captured in cross-sectional analyses drive compartmentalization but over time genital-specific viral lineages do not form; rather viruses mix between genital tract and blood. Methods. Eight women with ongoing HIV replication were studied during a period of 1.5 to 4.5 years. Multiple viral sequences were derived by single-genome amplification of the HIV C2-V5 region of env from genital secretions and blood plasma. Maximum likelihood phylogenies were evaluated for compartmentalization using 4 statistical tests. Results. In cross-sectional analyses compartmentalization of genital from blood viruses was detected in three of eight women by all tests; this was associated with tissue specific clades containing multiple monotypic sequences. In longitudinal analysis, the tissues-specific clades did not persist to form viral lineages. Rather, across women, HIV lineages were comprised of both genital tract and blood sequences. Conclusions. The observation of genital-specific HIV clades only in cross-sectional analysis and an absence of genital-specific lineages in longitudinal analyses suggest a dynamic interchange of HIV variants between the female genital tract and blood. PMID:23315326

Better Autologistic Regression

Directory of Open Access Journals (Sweden)

Mark A. Wolters

2017-11-01

Full Text Available Autologistic regression is an important probability model for dichotomous random variables observed along with covariate information. It has been used in various fields for analyzing binary data possessing spatial or network structure. The model can be viewed as an extension of the autologistic model (also known as the Ising model, quadratic exponential binary distribution, or Boltzmann machine to include covariates. It can also be viewed as an extension of logistic regression to handle responses that are not independent. Not all authors use exactly the same form of the autologistic regression model. Variations of the model differ in two respects. First, the variable coding—the two numbers used to represent the two possible states of the variables—might differ. Common coding choices are (zero, one and (minus one, plus one. Second, the model might appear in either of two algebraic forms: a standard form, or a recently proposed centered form. Little attention has been paid to the effect of these differences, and the literature shows ambiguity about their importance. It is shown here that changes to either coding or centering in fact produce distinct, non-nested probability models. Theoretical results, numerical studies, and analysis of an ecological data set all show that the differences among the models can be large and practically significant. Understanding the nature of the differences and making appropriate modeling choices can lead to significantly improved autologistic regression analyses. The results strongly suggest that the standard model with plus/minus coding, which we call the symmetric autologistic model, is the most natural choice among the autologistic variants.

Kenyan female sex workers' use of female-controlled nonbarrier modern contraception: do they use condoms less consistently?

Science.gov (United States)

Yam, Eileen A; Okal, Jerry; Musyoki, Helgar; Muraguri, Nicholas; Tun, Waimar; Sheehy, Meredith; Geibel, Scott

2016-03-01

To examine whether nonbarrier modern contraceptive use is associated with less consistent condom use among Kenyan female sex workers (FSWs). Researchers recruited 579 FSWs using respondent-driven sampling. We conducted multivariate logistic regression to examine the association between consistent condom use and female-controlled nonbarrier modern contraceptive use. A total of 98.8% reported using male condoms in the past month, and 64.6% reported using female-controlled nonbarrier modern contraception. In multivariate analysis, female-controlled nonbarrier modern contraceptive use was not associated with decreased condom use with clients or nonpaying partners. Consistency of condom use is not compromised when FSWs use available female-controlled nonbarrier modern contraception. FSWs should be encouraged to use condoms consistently, whether or not other methods are used simultaneously. Copyright © 2016 Elsevier Inc. All rights reserved.

Binge eating disorder and depressive symptoms among females of child-bearing age: the Korea Nurses' Health Study.

Science.gov (United States)

Kim, O; Kim, M S; Kim, J; Lee, J E; Jung, H

2018-01-17

Most studies regarding the relationship between binge eating disorder (BED) and depression have targeted obese populations. However, nurses, particularly female nurses, are one of the vocations that face these issues due to various reasons including high stress and shift work. This study investigated the prevalence of BED and the correlation between BED and severity of self-reported depressive symptoms among female nurses in South Korea. Participants were 7,267 female nurses, of which 502 had symptoms of BED. Using the propensity score matching (PSM) technique, 502 nurses with BED and 502 without BED were included in the analyses. Data were analyzed using descriptive statistics, Spearman's correlation, and multivariable ordinal logistic regression analysis. The proportion of binge eating disorder was 6.90% among the nurses, and 81.3% of nurses displayed some levels of depressive symptoms. Multivariable ordinal logistic regression analysis revealed that age (40 years old and older), alcohol consumption (frequent drinkers), self-rated health, sleep problems, and stress were associated with self-reported depression symptoms. Overall, after adjusting for confounders, nurses with BED had 1.80 times the risk (95% CI = [1.41-2.30]; p-value depression symptoms. Korean female nurse showed a higher prevalence of both binge eating disorder and depressive symptoms, and the association between the two factors was proven in the study. Therefore, hospital management and health policy makers should be alarmed and agreed on both examining nurses on such problems and providing organized and systematic assistance.

Analysis of Setting Efficacy in Young Male and Female Volleyball Players.

Science.gov (United States)

González-Silva, Jara; Domínguez, Alberto Moreno; Fernández-Echeverría, Carmen; Rabaz, Fernando Claver; Arroyo, M Perla Moreno

2016-12-01

The main objective of this study was to analyse the variables that predicted setting efficacy in complex I (KI) in volleyball, in formative categories and depending on gender. The study sample was comprised of 5842 game actions carried out by the 16 male category and the 18 female category teams that participated in the Under-16 Spanish Championship. The dependent variable was setting efficacy. The independent variables were grouped into: serve variables (a serve zone, the type of serve, striking technique, an in-game role of the server and serve direction), reception variables (a reception zone, a receiver player and reception efficacy) and setting variables (a setter's position, a setting zone, the type of a set, setting technique, a set's area and tempo of a set). Multinomial logistic regression showed that the best predictive variables of setting efficacy, both in female and male categories, were reception efficacy, setting technique and tempo of a set. In the male category, the jump serve was the greatest predictor of setting efficacy, while in the female category, it was the set's area. Therefore, in the male category, it was not only the preceding action that affected setting efficacy, but also the serve. On the contrary, in the female category, only variables of the action itself and of the previous action, reception, affected setting efficacy. The results obtained in the present study should be taken into account in the training process of both male and female volleyball players in formative stages.

Cortical activation during mental rotation in male-to-female and female-to-male transsexuals under hormonal treatment.

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Carrillo, Beatriz; Gómez-Gil, Esther; Rametti, Giuseppina; Junque, Carme; Gomez, Angel; Karadi, Kazmer; Segovia, Santiago; Guillamon, Antonio

2010-09-01

There is strong evidence of sex differences in mental rotation tasks. Transsexualism is an extreme gender identity disorder in which individuals seek cross-gender treatment to change their sex. The aim of our study was to investigate if male-to-female (MF) and female-to-male (FM) transsexuals receiving cross-sex hormonal treatment have different patterns of cortical activation during a three-dimensional (3D) mental rotation task. An fMRI study was performed using a 3-T scan in a sample of 18 MF and 19 FM under chronic cross-sex hormonal treatment. Twenty-three males and 19 females served as controls. The general pattern of cerebral activation seen while visualizing the rotated and non-rotated figures was similar for all four groups showing strong occipito-parieto-frontal brain activation. However, compared to control males, the activation of MF transsexuals during the task was lower in the superior parietal lobe. Compared to control females, MF transsexuals showed higher activation in orbital and right dorsolateral prefrontal regions and lower activation in the left prefrontal gyrus. FM transsexuals did not differ from either the MF transsexual or control groups. Regression analyses between cerebral activation and the number of months of hormonal treatment showed a significant negative correlation in parietal, occipital and temporal regions in the MF transsexuals. No significant correlations with time were seen in the FM transsexuals. In conclusion, although we did not find a specific pattern of cerebral activation in the FM transsexuals, we have identified a specific pattern of cerebral activation during a mental 3D rotation task in MF transsexuals under cross-sex hormonal treatment that differed from control males in the parietal region and from control females in the orbital prefrontal region. The hypoactivation in MF transsexuals in the parietal region could be due to the hormonal treatment or could reflect a priori cerebral differences between MF transsexual

Comparing parametric and nonparametric regression methods for panel data

DEFF Research Database (Denmark)

Czekaj, Tomasz Gerard; Henningsen, Arne

We investigate and compare the suitability of parametric and non-parametric stochastic regression methods for analysing production technologies and the optimal firm size. Our theoretical analysis shows that the most commonly used functional forms in empirical production analysis, Cobb......-Douglas and Translog, are unsuitable for analysing the optimal firm size. We show that the Translog functional form implies an implausible linear relationship between the (logarithmic) firm size and the elasticity of scale, where the slope is artificially related to the substitutability between the inputs....... The practical applicability of the parametric and non-parametric regression methods is scrutinised and compared by an empirical example: we analyse the production technology and investigate the optimal size of Polish crop farms based on a firm-level balanced panel data set. A nonparametric specification test...

Female married illiteracy as the most important continual determinant of total fertility rate among districts of Empowered Action Group States of India: Evidence from Annual Health Survey 2011–12

Science.gov (United States)

Kumar, Rajesh; Dogra, Vishal; Rani, Khushbu; Sahu, Kanti

2017-01-01

Background: District level determinants of total fertility rate in Empowered Action Group states of India can help in ongoing population stabilization programs in India. Objective: Present study intends to assess the role of district level determinants in predicting total fertility rate among districts of the Empowered Action Group states of India. Material and Methods: Data from Annual Health Survey (2011-12) was analysed using STATA and R software packages. Multiple linear regression models were built and evaluated using Akaike Information Criterion. For further understanding, recursive partitioning was used to prepare a regression tree. Results: Female married illiteracy positively associated with total fertility rate and explained more than half (53%) of variance. Under multiple linear regression model, married illiteracy, infant mortality rate, Ante natal care registration, household size, median age of live birth and sex ratio explained 70% of total variance in total fertility rate. In regression tree, female married illiteracy was the root node and splits at 42% determined TFR illiteracy with splits at 23% to determine TFR illiteracy is one of the most important determinants explaining total fertility rate among the districts of an Empowered Action Group states. Focus on female literacy is required to stabilize the population growth in long run. PMID:29416999

Differentiating regressed melanoma from regressed lichenoid keratosis.

Science.gov (United States)

Chan, Aegean H; Shulman, Kenneth J; Lee, Bonnie A

2017-04-01

Distinguishing regressed lichen planus-like keratosis (LPLK) from regressed melanoma can be difficult on histopathologic examination, potentially resulting in mismanagement of patients. We aimed to identify histopathologic features by which regressed melanoma can be differentiated from regressed LPLK. Twenty actively inflamed LPLK, 12 LPLK with regression and 15 melanomas with regression were compared and evaluated by hematoxylin and eosin staining as well as Melan-A, microphthalmia transcription factor (MiTF) and cytokeratin (AE1/AE3) immunostaining. (1) A total of 40% of regressed melanomas showed complete or near complete loss of melanocytes within the epidermis with Melan-A and MiTF immunostaining, while 8% of regressed LPLK exhibited this finding. (2) Necrotic keratinocytes were seen in the epidermis in 33% regressed melanomas as opposed to all of the regressed LPLK. (3) A dense infiltrate of melanophages in the papillary dermis was seen in 40% of regressed melanomas, a feature not seen in regressed LPLK. In summary, our findings suggest that a complete or near complete loss of melanocytes within the epidermis strongly favors a regressed melanoma over a regressed LPLK. In addition, necrotic epidermal keratinocytes and the presence of a dense band-like distribution of dermal melanophages can be helpful in differentiating these lesions. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Physical capacity and risk for long-term sickness absence: a prospective cohort study among 8664 female health care workers.

Science.gov (United States)

Rasmussen, Charlotte Diana Nørregaard; Andersen, Lars Louis; Clausen, Thomas; Strøyer, Jesper; Jørgensen, Marie Birk; Holtermann, Andreas

2015-05-01

To assess the prospective associations between self-reported physical capacity and risk of long-term sickness absence among female health care workers. Female health care workers answered a questionnaire about physical capacity and were followed in a national register of sickness absence lasting for two or more consecutive weeks during 1-year follow-up. Using Cox regression hazard ratio analyses adjusted for age, smoking, body mass index, physical workload, job seniority, psychosocial work conditions, and previous sickness absence, we modeled risk estimates for sickness absence from low and medium physical capacity. Low and medium aerobic fitness, low muscle strength, low flexibility, and low overall physical capacity significantly increased the risk for sickness absence with 20% to 34% compared with health care workers with high capacity. Low physical capacity increases the risk of long-term sickness absence among female health care workers.

Cessation-related weight concern among homeless male and female smokers.

Science.gov (United States)

Pinsker, Erika Ashley; Hennrikus, Deborah Jane; Erickson, Darin J; Call, Kathleen Thiede; Forster, Jean Lois; Okuyemi, Kolawole Stephen

2017-09-01

Concern about post-cessation weight gain is a barrier to making attempts to quit smoking; however, its effect on smoking cessation is unclear. In this study we examine cessation-related weight concern among the homeless, which hasn't been studied. Homeless males (n = 320) and females (n = 110) participating in a smoking cessation RCT in the Twin Cities, Minnesota from 2009 to 2011 completed surveys on cessation-related weight concern, smoking status, and components from the Behavioral Model for Vulnerable Populations. Generalized estimating equations were used to examine baseline predictors of cessation-related weight concern at baseline, the end of treatment, and 26-weeks follow-up. Logistic regression models were used to examine the relationship between cessation-related weight concern and smoking status at the end of treatment and follow-up. Females had higher cessation-related weight concern than males. Among males, older age, Black race, higher BMI, depression, and having health insurance were associated with higher cessation-related weight concern. Among females, nicotine dependence, greater cigarette consumption, indicating quitting is more important, older age of smoking initiation, and less support to quit from family were associated with higher cessation-related weight concern. In multivariate analyses, cessation-related weight concern decreased over time among females. Cessation-related weight concern wasn't associated with smoking cessation. Although several types of characteristics predicted cessation-related weight concern among males, only smoking characteristics predicted cessation-related weight concern among females. Given the small proportion of quitters in this study (8% of males and 5% of females), further research on the impact of cessation-related weight concern on smoking cessation among the homeless is warranted.

Human Immunodeficiency Viruses Appear Compartmentalized to the Female Genital Tract in Cross-Sectional Analyses but Genital Lineages Do Not Persist Over Time

OpenAIRE

Bull, Marta E.; Heath, Laura M.; McKernan-Mullin, Jennifer L.; Kraft, Kelli M.; Acevedo, Luis; Hitti, Jane E.; Cohn, Susan E.; Tapia, Kenneth A.; Holte, Sarah E.; Dragavon, Joan A.; Coombs, Robert W.; Mullins, James I.; Frenkel, Lisa M.

2013-01-01

Background. Whether unique human immunodeficiency type 1 (HIV) genotypes occur in the genital tract is important for vaccine development and management of drug resistant viruses. Multiple cross-sectional studies suggest HIV is compartmentalized within the female genital tract. We hypothesize that bursts of HIV replication and/or proliferation of infected cells captured in cross-sectional analyses drive compartmentalization but over time genital-specific viral lineages do not form; rather viru...

The effects of body image impairment on the quality of life of non-operated Portuguese female IBD patients.

Science.gov (United States)

Trindade, Inês A; Ferreira, Cláudia; Pinto-Gouveia, José

2017-02-01

Inflammatory bowel diseases (IBD) and their treatment are known to negatively impact on patients' body image, especially female patients. However, although there are broad evidences of body image impairment in female IBD patients, its negative impact on the quality of life (QoL) of non-operated women is not clearly and specifically studied. The aim of the current study was therefore to analyse, in a sample of non-operated female IBD patients, the factors that contribute to body image impairment and its impact on QoL. Ninety-six non-operated women (39.7 % with CD and 60.3 % with UC), aged between 18 and 40 years old, completed an online survey with validated self-report measures, which included the Body Image Scale and the WHO Brief Quality of Life Assessment Scale. Negative body image was correlated with lower psychological and physical QoL and increased corticosteroids use, associated medical complications, body mass index (BMI), and IBD symptomatology. Regression analyses revealed that BMI and IBD symptomatology significantly predicted body image impairment. Furthermore, results from path analyses indicated that BMI and IBD symptomatology's effect on psychological and physical QoL was mediated through the negative effects of body image impairment. This model explained 31 % of psychological QoL and 41 % of physical QoL. These findings suggest that non-operated female patients are subject to pervasive and harmful effects of body image impairment on psychological and physical functioning. Therefore, psychological interventions aiming to target body dissatisfaction should be implemented in the health care of IBD, independently of patients' operative status.

Covariate Imbalance and Adjustment for Logistic Regression Analysis of Clinical Trial Data

Science.gov (United States)

Ciolino, Jody D.; Martin, Reneé H.; Zhao, Wenle; Jauch, Edward C.; Hill, Michael D.; Palesch, Yuko Y.

2014-01-01

In logistic regression analysis for binary clinical trial data, adjusted treatment effect estimates are often not equivalent to unadjusted estimates in the presence of influential covariates. This paper uses simulation to quantify the benefit of covariate adjustment in logistic regression. However, International Conference on Harmonization guidelines suggest that covariate adjustment be pre-specified. Unplanned adjusted analyses should be considered secondary. Results suggest that that if adjustment is not possible or unplanned in a logistic setting, balance in continuous covariates can alleviate some (but never all) of the shortcomings of unadjusted analyses. The case of log binomial regression is also explored. PMID:24138438

Weight-related concerns and diet behaviors among urban young females: A cross-sectional study

Directory of Open Access Journals (Sweden)

Shabnam Omidvar

2016-01-01

Full Text Available Background: Females are more likely than males to perceive themselves as too heavy, this has been explained in terms of the equation of “female beauty with extreme thinness.” Therefore, females are in general prone to develop unhealthy behaviors for weight management. Wrong weight control behaviors have significant health consequences. Objectives: To investigate the body weight concerns, body satisfaction, and weight control behaviors among young females and their association with age and socioeconomic status (SES. Materials and Methods: A cross-sectional study conducted in urban areas from a major city in South India. About 650 healthy unmarried females aged 15–25 years formed the study population. Self-reporting questionnaires were used to obtain relevant data. The categorical data were analyzed using Chi-square, correlation, and regression analyses by SPSS version 16. Results: Most overweight and obese subjects perceived themselves as overweight. Adolescents were more likely to report themselves as overweight. The perceived weight, body satisfaction, and weight control behaviors are influenced by weight status and age of the subjects. However, SES of the participants did not exhibit effect of others' opinion about their weight and body satisfaction as well as weight management behaviors. Conclusion: The high prevalence of weight-related concerns suggests that all females should be reached with appropriate information and interventions. Healthy weight control practices need to be explicitly promoted and unhealthy practices discouraged. Young females need special attention toward weight management.

Variable selection and model choice in geoadditive regression models.

Science.gov (United States)

Kneib, Thomas; Hothorn, Torsten; Tutz, Gerhard

2009-06-01

Model choice and variable selection are issues of major concern in practical regression analyses, arising in many biometric applications such as habitat suitability analyses, where the aim is to identify the influence of potentially many environmental conditions on certain species. We describe regression models for breeding bird communities that facilitate both model choice and variable selection, by a boosting algorithm that works within a class of geoadditive regression models comprising spatial effects, nonparametric effects of continuous covariates, interaction surfaces, and varying coefficients. The major modeling components are penalized splines and their bivariate tensor product extensions. All smooth model terms are represented as the sum of a parametric component and a smooth component with one degree of freedom to obtain a fair comparison between the model terms. A generic representation of the geoadditive model allows us to devise a general boosting algorithm that automatically performs model choice and variable selection.

Multiple regression and beyond an introduction to multiple regression and structural equation modeling

CERN Document Server

Keith, Timothy Z

2014-01-01

Multiple Regression and Beyond offers a conceptually oriented introduction to multiple regression (MR) analysis and structural equation modeling (SEM), along with analyses that flow naturally from those methods. By focusing on the concepts and purposes of MR and related methods, rather than the derivation and calculation of formulae, this book introduces material to students more clearly, and in a less threatening way. In addition to illuminating content necessary for coursework, the accessibility of this approach means students are more likely to be able to conduct research using MR or SEM--and more likely to use the methods wisely. Covers both MR and SEM, while explaining their relevance to one another Also includes path analysis, confirmatory factor analysis, and latent growth modeling Figures and tables throughout provide examples and illustrate key concepts and techniques For additional resources, please visit: http://tzkeith.com/.

PARAMETRIC AND NON PARAMETRIC (MARS: MULTIVARIATE ADDITIVE REGRESSION SPLINES) LOGISTIC REGRESSIONS FOR PREDICTION OF A DICHOTOMOUS RESPONSE VARIABLE WITH AN EXAMPLE FOR PRESENCE/ABSENCE OF AMPHIBIANS

Science.gov (United States)

The purpose of this report is to provide a reference manual that could be used by investigators for making informed use of logistic regression using two methods (standard logistic regression and MARS). The details for analyses of relationships between a dependent binary response ...

Somatic symptoms among US adolescent females: associations with sexual and physical violence exposure.

Science.gov (United States)

Halpern, Carolyn Tucker; Tucker, Christine M; Bengtson, Angela; Kupper, Lawrence L; McLean, Samuel A; Martin, Sandra L

2013-12-01

The objective of this study is to examine the association between physical and sexual violence exposure and somatic symptoms among female adolescents. We studied a nationally representative sample of 8,531 females, aged 11-21 years, who participated in the 1994-1995 Wave I of the National Longitudinal Study of Adolescent Health (Add Health). Female adolescents were asked how often they had experienced 16 specific somatic symptoms during the past 12 months. Two summary categorical measures were constructed based on tertiles of the distributions for the entire female sample: (a) total number of different types of symptoms experienced, and (b) number of frequent (once a week or more often) different symptoms experienced. Groups were mutually exclusive. We examined associations between adolescents' violence exposure and somatic symptoms using multinomial logistic regression analyses. About 5 % of adolescent females reported both sexual and non-sexual violence, 3 % reported sexual violence only, 36 % reported non-sexual violence only, and 57 % reported no violence. Adolescents who experienced both sexual and non-sexual violence were the most likely to report many different symptoms and to experience very frequent or chronic symptoms. Likelihood of high symptomatology was next highest among adolescents who experienced sexual violence only, followed by females who experienced non-sexual violence only. Findings support an exposure-response association between violence exposure and somatic symptoms, suggesting that symptoms can be markers of victimization. Treating symptoms alone, without addressing the potential violence experienced, may not adequately improve adolescents' somatic complaints and well-being.

Correcting for multivariate measurement error by regression calibration in meta-analyses of epidemiological studies.

NARCIS (Netherlands)

Kromhout, D.

2009-01-01

Within-person variability in measured values of multiple risk factors can bias their associations with disease. The multivariate regression calibration (RC) approach can correct for such measurement error and has been applied to studies in which true values or independent repeat measurements of the

[High prevalence of work-family conflict among female physicians: lack of social support as a potential antecedent].

Science.gov (United States)

Adám, Szilvia

2009-12-13

According to stress theory, social support from work and non-work-related sources may influence the level of perceived work-family conflict. Despite the high prevalence of work-family conflict as a source of distress among female physicians, no information is available on the associations between work-family conflict and social support in a traditional, family-centric cultural setting, where female role expectations are demanding. The author hypothesized that high prevalence of work-family conflict could be attributed to the lack of social support among female physicians. To investigate the prevalence and psychosocial characteristics of social support and its relations to work-family conflict among female physicians. Quantitative and qualitative study using questionnaires ( n = 420) and in-depth interviews ( n = 123) among female and male physicians. Female physicians reported significantly higher mean level and prevalence of work-family conflict compared to men. The predominant form of work-family was work-to-family conflict among physicians; however, significantly more female physicians experienced family-to-work conflict and strain-based work-family conflict compared to men (39% vs. 18% and 68% vs. 20%, respectively). Significantly more male physicians experienced time-based work-family conflict compared to women. Content analyses of interview data revealed that provision of support to physicians manifested itself in parental support in career selection, spousal support with household duties, peer support with enabling access to professional role models-mentors, peer support to ensure gender equity, and organizational support with family-centric policies. Female physicians reported significantly less parental, spousal, and peer support compared to men. Female physicians lacking parental, peer, or organizational support experienced significantly higher level of work-family conflict compared to appropriate control. In regression analyses, high job demands, job

[Prevalence and factors associated with intimate partner abuse in female users of public health services in Mexico: a comparative analyses].

Science.gov (United States)

Ávila-Burgos, Leticia; Valdez-Santiagob, Rosario; Barroso-Quiab, Abigail; Híjar, Martha; Rojas, Rosalba; Del Río-Zolezzi, Aurora

2014-01-01

To analyze the evolution of the prevalence in intimate partner violence during the years 2003 and 2006 in Mexico, identifying factors associated with its severity, comparing our results with findings from 2003. Data from the Encuesta Nacional de Violencia contra las Mujeres (ENVIM 2006) was used; it has urban-rural national representation of female users of Mexican public health services. A total of 22,318 women above 14 years of age were interviewed. A multinomial logistic regression model was adjusted. The dependent variable was the Index of Intimate Partner Abuse. Intimate partner abuse increased 17% in comparison to the year 2003. Women's personal history of childhood abuse (ORA= 5.12, 95% CI4.15-6.30) and rape (ORA = 3.5, 95% CI = 2.66-4.62) were the most important women's factors that were found associated with severe violence. Male partner's daily alcohol consumption increased eleven fold the possibility of severe violence; higher disagreement with traditional female gender roles and higher education of both partners were protective factors. Factors associated with violence and their severities were consistent with findings reported in 2003. Intimate partner violence is a highly prevalent social problem which requires comprehensive strategies supporting empowerment of women through higher education, early detection and care of those battered, as well as structured interventions to prevent violence in future generations.

Neural correlates of moral and non-moral emotion in female psychopathy

Directory of Open Access Journals (Sweden)

Carla L Harenski

2014-09-01

Full Text Available This study presents the first neuroimaging investigation of female psychopathy in an incarcerated population. Prior studies have found that male psychopathy is associated with reduced limbic and paralimbic activation when processing emotional stimuli and making moral judgments. The goal of this study was to investigate whether these findings extend to female psychopathy. During fMRI scanning, 157 incarcerated and 46 non-incarcerated female participants viewed unpleasant pictures, half which depicted moral transgressions, and neutral pictures. Participants rated each picture on moral transgression severity. Psychopathy was assessed using the Psychopathy Checklist-Revised (PCL-R in all incarcerated participants. Non-incarcerated participants were included as a control group to derive brain regions of interest associated with viewing unpleasant versus neutral pictures (emotion contrast, and unpleasant pictures depicting moral transgressions versus unpleasant pictures without moral transgressions (moral contrast. Regression analyses in the incarcerated group examined the association between PCL-R scores and brain activation in the emotion and moral contrasts. Results of the emotion contrast revealed a negative correlation between PCL-R scores and activation in the right amygdala and rostral anterior cingulate. Results of the moral contrast revealed a negative correlation between PCL-R scores and activation in the right temporo-parietal junction. These results indicate that female psychopathy, like male psychopathy, is characterized by reduced limbic activation during emotion processing. In contrast, reduced temporo-parietal activation to moral transgressions has been less observed in male psychopathy. These results extend prior findings in male psychopathy to female psychopathy, and reveal aberrant neural responses to morally-salient stimuli that may be unique to female psychopathy.

Analysis of Setting Efficacy in Young Male and Female Volleyball Players

Directory of Open Access Journals (Sweden)

González-Silva Jara

2016-12-01

Full Text Available The main objective of this study was to analyse the variables that predicted setting efficacy in complex I (KI in volleyball, in formative categories and depending on gender. The study sample was comprised of 5842 game actions carried out by the 16 male category and the 18 female category teams that participated in the Under-16 Spanish Championship. The dependent variable was setting efficacy. The independent variables were grouped into: serve variables (a serve zone, the type of serve, striking technique, an in-game role of the server and serve direction, reception variables (a reception zone, a receiver player and reception efficacy and setting variables (a setter‘s position, a setting zone, the type of a set, setting technique, a set’s area and tempo of a set. Multinomial logistic regression showed that the best predictive variables of setting efficacy, both in female and male categories, were reception efficacy, setting technique and tempo of a set. In the male category, the jump serve was the greatest predictor of setting efficacy, while in the female category, it was the set’s area. Therefore, in the male category, it was not only the preceding action that affected setting efficacy, but also the serve. On the contrary, in the female category, only variables of the action itself and of the previous action, reception, affected setting efficacy. The results obtained in the present study should be taken into account in the training process of both male and female volleyball players in formative stages.

Measurement Error in Education and Growth Regressions

NARCIS (Netherlands)

Portela, M.; Teulings, C.N.; Alessie, R.

The perpetual inventory method used for the construction of education data per country leads to systematic measurement error. This paper analyses the effect of this measurement error on GDP regressions. There is a systematic difference in the education level between census data and observations

Measurement error in education and growth regressions

NARCIS (Netherlands)

Portela, Miguel; Teulings, Coen; Alessie, R.

2004-01-01

The perpetual inventory method used for the construction of education data per country leads to systematic measurement error. This paper analyses the effect of this measurement error on GDP regressions. There is a systematic difference in the education level between census data and observations

Regression of a vaginal leiomyoma after ovariohysterectomy in a dog: a case report.

Science.gov (United States)

Sathya, Suresh; Linn, Kathleen

2014-01-01

An 11 yr old female mixed-breed Siberian husky was presented with a history of sanguineous vaginal discharge, swelling of the perineal area, decreased appetite, and lethargy. A single, large vaginal leiomyoma and multiple mammary tumors were diagnosed. Mastectomy and ovariohysterectomy were performed. The vaginal leiomyoma regressed completely after ovariohysterectomy. This is the first reported case of spontaneous regression of a vaginal leiomyoma after ovariohysterectomy in a dog.

Female children with incarcerated adult family members at risk for life-long neurological decline

Science.gov (United States)

Brewer-Smyth, Kathleen; Pohlig, Ryan T.; Bucurescu, Gabriel

2016-01-01

A secondary analysis of data from adult female prison inmates in the mid-Atlantic United States defined relationships between having incarcerated adult family members during childhood and neurological outcomes. Of 135 inmates, 99(73%) had one or more incarcerated adult family members during childhood. Regression analyses revealed that having incarcerated adult family members was related to greater frequency and severity of childhood abuse and higher incidence of neurological deficits in adulthood, especially related to traumatic brain injuries, compared to those without incarcerated adult family members. Along with being role models, adult family members impact the neurological health of children throughout their lifespan. PMID:26788781

Body image satisfaction and self-esteem in Thai female adolescents: the moderating role of self-compassion.

Science.gov (United States)

Pisitsungkagarn, Kullaya; Taephant, Nattasuda; Attasaranya, Ploychompoo

2014-01-01

Body image satisfaction significantly influences self-esteem in female adolescents. Increased reports of lowered satisfaction in this population have raised concerns regarding their compromised self-esteem. This research study, therefore, sought to identify a culturally significant moderator of the association between body image satisfaction and self-esteem in Thai female adolescents. Orientation toward self-compassion, found to be particularly high in Thailand, was examined. A total of 302 Thai female undergraduates from three large public and private universities in the Bangkok metropolitan area responded to a set of questionnaires, which measured demographic information, body image satisfaction, self-compassion, and self-esteem. Data were analyzed using correlation and multiple regression analyses. Self-compassion was tested as a moderator of the relationship between body image satisfaction and self-esteem. Although its effect was relatively small, self-compassion significantly moderated the positive relationship between body image satisfaction and self-esteem. The relationship became less stringent for those with high self-compassion. The cultivation of self-compassion was recommended in female adolescents. In addition to moderating the association between body image satisfaction and self-esteem, the benefits to health and well-being of generalizing this cultivation are discussed.

Online Female Escort Advertisements

Directory of Open Access Journals (Sweden)

James D. Griffith

2016-05-01

Full Text Available Female escorts represent an occupational group that charges a fee for sex, which can be regarded as an extreme form of short-term mating. The present study examined if the fees charged by escorts are related to traits typically associated with female short-term mate value. A total of 2,925 advertisements for female escorts offering sexual services in the United States were examined, as a customized software program was used to download all the advertisements from an online escort directory. The advertisement content was coded, and relationships between advertised physical characteristics and the hourly rate charged by female escorts were examined. The analyses showed that higher fees were associated with female escorts who advertised a waist-to-hip ratio near 0.7, lower weight and body mass index, younger age, and photographic displays of breast and buttocks nudity. The findings provide evidence that evolutionarily relevant traits associated with female short-term mate value are systematically related to fees charged for sexual services.

Panel data specifications in nonparametric kernel regression

DEFF Research Database (Denmark)

Czekaj, Tomasz Gerard; Henningsen, Arne

parametric panel data estimators to analyse the production technology of Polish crop farms. The results of our nonparametric kernel regressions generally differ from the estimates of the parametric models but they only slightly depend on the choice of the kernel functions. Based on economic reasoning, we...

Risk for coerced sex among female youth in Ghana: roles of family context, school enrollment and relationship experience.

Science.gov (United States)

Bingenheimer, Jeffrey B; Reed, Elizabeth

2014-12-01

A better understanding is needed of the variables that may influence the risk of experiencing coerced sex among adolescent females in Sub-Saharan Africa. Data were collected from 700 female respondents who were interviewed in 2010 and 2012 waves of a longitudinal study of behavioral risk for HIV infection among youth aged 13-14 or 18-19 and living in two towns in southeastern Ghana. A series of logistic regression models examined the influences of household composition and wealth, four family process variables (behavioral control, relationship quality, financial support, conflict), school enrollment and relationship experience on females' risk of experiencing coerced sex. Eighteen percent of respondents reported having experienced coerced sex prior to Wave 1, and 13% experienced it between Waves 1 and 2. In both cross-sectional and prospective models, the variable with the strongest association with having experienced coerced sex was having ever had a boyfriend (fully adjusted odds ratios, 4.5 and 2.6, respectively). In cross-sectional analyses, parental behavioral control was negatively associated with risk for coerced sex, while parental conflict was positively associated; these associations were not significant in the prospective analyses. Having a boyfriend appears to be the primary predictor of coerced sex among young females, beyond any influence of family, school or other household variables. More research is needed to understand the context of females' relationships with boyfriends in an effort to reduce the risk of sexual coercion and to promote the prevention of sexual violence perpetrated by males within these relationships.

The relation of female circumcision to sexual behavior in Kenya and Nigeria.

Science.gov (United States)

Mpofu, Sibonginkosi; Odimegwu, Clifford; De Wet, Nicole; Adedini, Sunday; Akinyemi, Joshua

2017-08-01

One of the reasons for the perpetuation of female circumcision is that it controls female sexuality. In this study, the authors examined the relationship between female circumcision and the sexual behavior of women in Kenya and Nigeria. Data on women who were aware of circumcision and were circumcised were extracted from the Kenya Demographic and Health Survey of 2008-09 as well as the Nigeria Demographic and Health Survey of 2008. The sample size was 7,344 for Kenya and 16,294 for Nigeria. The outcome variables were age at first intercourse and total lifetime number of sexual partners. The study hypothesis was that women who were circumcised were less likely to have initiated sex early and to have only one sex partner. Cox proportional hazards regression and Poisson regression were used to examine the relations of female circumcision and other selected variables to sexual behavior. No association was observed between female circumcision and the outcomes for sexual behavior of women in Kenya and Nigeria. The argument of sexual chastity is insufficient to sustain the perpetuation of female circumcision.

Retro-regression--another important multivariate regression improvement.

Science.gov (United States)

Randić, M

2001-01-01

We review the serious problem associated with instabilities of the coefficients of regression equations, referred to as the MRA (multivariate regression analysis) "nightmare of the first kind". This is manifested when in a stepwise regression a descriptor is included or excluded from a regression. The consequence is an unpredictable change of the coefficients of the descriptors that remain in the regression equation. We follow with consideration of an even more serious problem, referred to as the MRA "nightmare of the second kind", arising when optimal descriptors are selected from a large pool of descriptors. This process typically causes at different steps of the stepwise regression a replacement of several previously used descriptors by new ones. We describe a procedure that resolves these difficulties. The approach is illustrated on boiling points of nonanes which are considered (1) by using an ordered connectivity basis; (2) by using an ordering resulting from application of greedy algorithm; and (3) by using an ordering derived from an exhaustive search for optimal descriptors. A novel variant of multiple regression analysis, called retro-regression (RR), is outlined showing how it resolves the ambiguities associated with both "nightmares" of the first and the second kind of MRA.

Modified Regression Correlation Coefficient for Poisson Regression Model

Science.gov (United States)

Kaengthong, Nattacha; Domthong, Uthumporn

2017-09-01

This study gives attention to indicators in predictive power of the Generalized Linear Model (GLM) which are widely used; however, often having some restrictions. We are interested in regression correlation coefficient for a Poisson regression model. This is a measure of predictive power, and defined by the relationship between the dependent variable (Y) and the expected value of the dependent variable given the independent variables [E(Y|X)] for the Poisson regression model. The dependent variable is distributed as Poisson. The purpose of this research was modifying regression correlation coefficient for Poisson regression model. We also compare the proposed modified regression correlation coefficient with the traditional regression correlation coefficient in the case of two or more independent variables, and having multicollinearity in independent variables. The result shows that the proposed regression correlation coefficient is better than the traditional regression correlation coefficient based on Bias and the Root Mean Square Error (RMSE).

Comparative analysis of female physicists in the physical sciences: Motivation and background variables

Science.gov (United States)

Dabney, Katherine P.; Tai, Robert H.

2014-06-01

The majority of existing science, technology, engineering, and mathematics (STEM) research studies compare women to men, yet a paucity of research exists that examines what differentiates female career choice within the physical sciences. In light of these research trends and recommendations, this study examines the following question: On average, do females who select physics as compared to chemistry doctoral programs differ in their reported personal motivations and background factors prior to entering the field? This question is analyzed using variables from the Project Crossover Survey data set through a subset of female physical science doctoral students and scientists (n =1137). A logistic regression analysis and prototypical odds ratio uncover what differentiates women in the physical sciences based on their academic achievement and experiences ranging from high school through undergraduate education. Results indicate that females who have negative undergraduate chemistry experiences as well as higher grades and positive experiences in undergraduate physics are more likely to pursue a career in physics as opposed to chemistry. Conclusions suggest that a greater emphasis should be placed on the classroom experiences that are provided to females in gateway physics courses. Analyses show that women are not a single entity that should only be examined as a whole group or in comparison to men. Instead women can be compared to one another to see what influences their differences in educational experiences and career choice in STEM-based fields as well as other academic areas of study.

Comparative analysis of female physicists in the physical sciences: Motivation and background variables

Directory of Open Access Journals (Sweden)

Katherine P. Dabney

2014-02-01

Full Text Available The majority of existing science, technology, engineering, and mathematics (STEM research studies compare women to men, yet a paucity of research exists that examines what differentiates female career choice within the physical sciences. In light of these research trends and recommendations, this study examines the following question: On average, do females who select physics as compared to chemistry doctoral programs differ in their reported personal motivations and background factors prior to entering the field? This question is analyzed using variables from the Project Crossover Survey data set through a subset of female physical science doctoral students and scientists (n=1137. A logistic regression analysis and prototypical odds ratio uncover what differentiates women in the physical sciences based on their academic achievement and experiences ranging from high school through undergraduate education. Results indicate that females who have negative undergraduate chemistry experiences as well as higher grades and positive experiences in undergraduate physics are more likely to pursue a career in physics as opposed to chemistry. Conclusions suggest that a greater emphasis should be placed on the classroom experiences that are provided to females in gateway physics courses. Analyses show that women are not a single entity that should only be examined as a whole group or in comparison to men. Instead women can be compared to one another to see what influences their differences in educational experiences and career choice in STEM-based fields as well as other academic areas of study.

Age differences in change-of-direction performance and its subelements in female football players.

Science.gov (United States)

Hirose, Norikazu; Nakahori, Chikako

2015-05-01

To describe cross-sectional age differences in change-of-direction performance (CODp) in female football players and investigate the relationship between CODp and linear-sprint speed, muscle power, and body size. A sample of 135 well-trained female football players was divided into 8 age groups. Anthropometry (height, body mass, and lean body mass) and athletic performance (10-m sprint speed, 10-m×5-CODp, and 5-step bounding distance) were compared to determine interage differences using ANOVA. Then, the participants were divided into 3 age groups: 12- to 14-y-olds, 15- to 17-y-olds, and ≥18 y-olds. Simple- and multiple-regression analyses were conducted to determine the correlation between CODp and the other measurement variables in each age group. Age-related differences were found for CODp (F=10.41, Pfemale players. Linear-sprint speed, muscle power, and body size were weakly correlated with the age differences in CODp.

[Establishment of cervical vertebral skeletal maturation of female children in Shanghai].

Science.gov (United States)

Sun, Yan; Chen, Rong-jing; Yu, Quan; Fan, Li; Chen, Wei; Shen, Gang

2009-06-01

To establish a method for quantitatively evaluating skeletal maturation of cervical vertebrae of female children in Shanghai. The samples were selected from lateral cephalometric radiographs of 240 Shanghai girls, aged 8 to 15 years. The parameters were measured to indicate the morphological changes of the third (C3) and fourth (C4) vertebrae in width, height and the depth of the inferior curvature. The independent-sample t test and stepwise multiple regression analysis were used to estimate the growth status and the ratios of C3, C4 cervical vertebrae by SPSS 15.0 software package. The physical and morphological contour of C3, C4 cervical vertebrae increased proportionately with the increment of age. The regression formula for indicating cervical vertebral skeletal age of female children in Shanghai was expressed by the equation Y= -5.696+8.010 AH3/AP3+6.654 AH3/H3+6.045AH4/PH4 (r=0.912). The regression formula resulted from morphological measurements quantitatively indicates the skeletal maturation of cervical vertebrae of female children in Shanghai.

APPLICATION OF MULTIPLE LOGISTIC REGRESSION, BAYESIAN LOGISTIC AND CLASSIFICATION TREE TO IDENTIFY THE SIGNIFICANT FACTORS INFLUENCING CRASH SEVERITY

Directory of Open Access Journals (Sweden)

MILAD TAZIK

2017-11-01

Full Text Available Identifying cases in which road crashes result in fatality or injury of drivers may help improve their safety. In this study, datasets of crashes happened in TehranQom freeway, Iran, were examined by three models (multiple logistic regression, Bayesian logistic and classification tree to analyse the contribution of several variables to fatal accidents. For multiple logistic regression and Bayesian logistic models, the odds ratio was calculated for each variable. The model which best suited the identification of accident severity was determined based on AIC and DIC criteria. Based on the results of these two models, rollover crashes (OR = 14.58, %95 CI: 6.8-28.6, not using of seat belt (OR = 5.79, %95 CI: 3.1-9.9, exceeding speed limits (OR = 4.02, %95 CI: 1.8-7.9 and being female (OR = 2.91, %95 CI: 1.1-6.1 were the most important factors in fatalities of drivers. In addition, the results of the classification tree model have verified the findings of the other models.

SPECIFICS OF THE APPLICATIONS OF MULTIPLE REGRESSION MODEL IN THE ANALYSES OF THE EFFECTS OF GLOBAL FINANCIAL CRISES

Directory of Open Access Journals (Sweden)

Željko V. Račić

2010-12-01

Full Text Available This paper aims to present the specifics of the application of multiple linear regression model. The economic (financial crisis is analyzed in terms of gross domestic product which is in a function of the foreign trade balance (on one hand and the credit cards, i.e. indebtedness of the population on this basis (on the other hand, in the USA (from 1999. to 2008. We used the extended application model which shows how the analyst should run the whole development process of regression model. This process began with simple statistical features and the application of regression procedures, and ended with residual analysis, intended for the study of compatibility of data and model settings. This paper also analyzes the values of some standard statistics used in the selection of appropriate regression model. Testing of the model is carried out with the use of the Statistics PASW 17 program.

Independent contrasts and PGLS regression estimators are equivalent.

Science.gov (United States)

Blomberg, Simon P; Lefevre, James G; Wells, Jessie A; Waterhouse, Mary

2012-05-01

We prove that the slope parameter of the ordinary least squares regression of phylogenetically independent contrasts (PICs) conducted through the origin is identical to the slope parameter of the method of generalized least squares (GLSs) regression under a Brownian motion model of evolution. This equivalence has several implications: 1. Understanding the structure of the linear model for GLS regression provides insight into when and why phylogeny is important in comparative studies. 2. The limitations of the PIC regression analysis are the same as the limitations of the GLS model. In particular, phylogenetic covariance applies only to the response variable in the regression and the explanatory variable should be regarded as fixed. Calculation of PICs for explanatory variables should be treated as a mathematical idiosyncrasy of the PIC regression algorithm. 3. Since the GLS estimator is the best linear unbiased estimator (BLUE), the slope parameter estimated using PICs is also BLUE. 4. If the slope is estimated using different branch lengths for the explanatory and response variables in the PIC algorithm, the estimator is no longer the BLUE, so this is not recommended. Finally, we discuss whether or not and how to accommodate phylogenetic covariance in regression analyses, particularly in relation to the problem of phylogenetic uncertainty. This discussion is from both frequentist and Bayesian perspectives.

Skeletal height estimation from regression analysis of sternal lengths in a Northwest Indian population of Chandigarh region: a postmortem study.

Science.gov (United States)

Singh, Jagmahender; Pathak, R K; Chavali, Krishnadutt H

2011-03-20

Skeletal height estimation from regression analysis of eight sternal lengths in the subjects of Chandigarh zone of Northwest India is the topic of discussion in this study. Analysis of eight sternal lengths (length of manubrium, length of mesosternum, combined length of manubrium and mesosternum, total sternal length and first four intercostals lengths of mesosternum) measured from 252 male and 91 female sternums obtained at postmortems revealed that mean cadaver stature and sternal lengths were more in North Indians and males than the South Indians and females. Except intercostal lengths, all the sternal lengths were positively correlated with stature of the deceased in both sexes (P regression analysis of sternal lengths was found more useful than the linear regression for stature estimation. Using multivariate regression analysis, the combined length of manubrium and mesosternum in both sexes and the length of manubrium along with 2nd and 3rd intercostal lengths of mesosternum in males were selected as best estimators of stature. Nonetheless, the stature of males can be predicted with SEE of 6.66 (R(2) = 0.16, r = 0.318) from combination of MBL+BL_3+LM+BL_2, and in females from MBL only, it can be estimated with SEE of 6.65 (R(2) = 0.10, r = 0.318), whereas from the multiple regression analysis of pooled data, stature can be known with SEE of 6.97 (R(2) = 0.387, r = 575) from the combination of MBL+LM+BL_2+TSL+BL_3. The R(2) and F-ratio were found to be statistically significant for almost all the variables in both the sexes, except 4th intercostal length in males and 2nd to 4th intercostal lengths in females. The 'major' sternal lengths were more useful than the 'minor' ones for stature estimation The universal regression analysis used by Kanchan et al. [39] when applied to sternal lengths, gave satisfactory estimates of stature for males only but female stature was comparatively better estimated from simple linear regressions. But they are not proposed for the

Associations between Bisphenol A Exposure and Reproductive Hormones among Female Workers.

Science.gov (United States)

Miao, Maohua; Yuan, Wei; Yang, Fen; Liang, Hong; Zhou, Zhijun; Li, Runsheng; Gao, Ersheng; Li, De-Kun

2015-10-22

The associations between Bisphenol-A (BPA) exposure and reproductive hormone levels among women are unclear. A cross-sectional study was conducted among female workers from BPA-exposed and unexposed factories in China. Women's blood samples were collected for assay of follicle-stimulating hormone (FSH), luteinizing hormone (LH), 17β-Estradiol (E2), prolactin (PRL), and progesterone (PROG). Their urine samples were collected for BPA measurement. In the exposed group, time weighted average exposure to BPA for an 8-h shift (TWA8), a measure incorporating historic exposure level, was generated based on personal air sampling. Multiple linear regression analyses were used to examine linear associations between urine BPA concentration and reproductive hormones after controlling for potential confounders. A total of 106 exposed and 250 unexposed female workers were included in this study. A significant positive association between increased urine BPA concentration and higher PRL and PROG levels were observed. Similar associations were observed after the analysis was carried out separately among the exposed and unexposed workers. In addition, a positive association between urine BPA and E2 was observed among exposed workers with borderline significance, while a statistically significant inverse association between urine BPA and FSH was observed among unexposed group. The results suggest that BPA exposure may lead to alterations in female reproductive hormone levels.

Associations between Bisphenol A Exposure and Reproductive Hormones among Female Workers

Directory of Open Access Journals (Sweden)

Maohua Miao

2015-10-01

Full Text Available The associations between Bisphenol-A (BPA exposure and reproductive hormone levels among women are unclear. A cross-sectional study was conducted among female workers from BPA-exposed and unexposed factories in China. Women’s blood samples were collected for assay of follicle-stimulating hormone (FSH, luteinizing hormone (LH, 17β-Estradiol (E2, prolactin (PRL, and progesterone (PROG. Their urine samples were collected for BPA measurement. In the exposed group, time weighted average exposure to BPA for an 8-h shift (TWA8, a measure incorporating historic exposure level, was generated based on personal air sampling. Multiple linear regression analyses were used to examine linear associations between urine BPA concentration and reproductive hormones after controlling for potential confounders. A total of 106 exposed and 250 unexposed female workers were included in this study. A significant positive association between increased urine BPA concentration and higher PRL and PROG levels were observed. Similar associations were observed after the analysis was carried out separately among the exposed and unexposed workers. In addition, a positive association between urine BPA and E2 was observed among exposed workers with borderline significance, while a statistically significant inverse association between urine BPA and FSH was observed among unexposed group. The results suggest that BPA exposure may lead to alterations in female reproductive hormone levels.

Spontaneous regression of intracranial malignant lymphoma

International Nuclear Information System (INIS)

Kojo, Nobuto; Tokutomi, Takashi; Eguchi, Gihachirou; Takagi, Shigeyuki; Matsumoto, Tomie; Sasaguri, Yasuyuki; Shigemori, Minoru.

1988-01-01

In a 46-year-old female with a 1-month history of gait and speech disturbances, computed tomography (CT) demonstrated mass lesions of slightly high density in the left basal ganglia and left frontal lobe. The lesions were markedly enhanced by contrast medium. The patient received no specific treatment, but her clinical manifestations gradually abated and the lesions decreased in size. Five months after her initial examination, the lesions were absent on CT scans; only a small area of low density remained. Residual clinical symptoms included mild right hemiparesis and aphasia. After 14 months the patient again deteriorated, and a CT scan revealed mass lesions in the right frontal lobe and the pons. However, no enhancement was observed in the previously affected regions. A biopsy revealed malignant lymphoma. Despite treatment with steroids and radiation, the patient's clinical status progressively worsened and she died 27 months after initial presentation. Seven other cases of spontaneous regression of primary malignant lymphoma have been reported. In this case, the mechanism of the spontaneous regression was not clear, but changes in immunologic status may have been involved. (author)

[Female erotic dreams and female seed in ancient Greek medicine].

Science.gov (United States)

Andò, Valeria

2009-01-01

This paper analyses passages of the Hippocratic Corpus, of Aristotle and Galen about oneirogmòs, spermatic emission during sleep, referring specifically to women. Into the Hippocratic texts there is only one gynaecological case among many cases about males: for them this nocturnal emission is symptom of dangerous illness and De genitura gives a causal explanation of such phaenomenon. Instead, in Aristotle and Galen erotic dream is evidence for or against emission of female seed and female contribution to generation. As the argument ofHistoria animalium book X shows clear theoretical differences from that of De generatione animalium, the topic of erotic dream also concerns issues of authenticity.

Logistic regression and multiple classification analyses to explore risk factors of under-5 mortality in bangladesh

International Nuclear Information System (INIS)

Bhowmik, K.R.; Islam, S.

2016-01-01

Logistic regression (LR) analysis is the most common statistical methodology to find out the determinants of childhood mortality. However, the significant predictors cannot be ranked according to their influence on the response variable. Multiple classification (MC) analysis can be applied to identify the significant predictors with a priority index which helps to rank the predictors. The main objective of the study is to find the socio-demographic determinants of childhood mortality at neonatal, post-neonatal, and post-infant period by fitting LR model as well as to rank those through MC analysis. The study is conducted using the data of Bangladesh Demographic and Health Survey 2007 where birth and death information of children were collected from their mothers. Three dichotomous response variables are constructed from children age at death to fit the LR and MC models. Socio-economic and demographic variables significantly associated with the response variables separately are considered in LR and MC analyses. Both the LR and MC models identified the same significant predictors for specific childhood mortality. For both the neonatal and child mortality, biological factors of children, regional settings, and parents socio-economic status are found as 1st, 2nd, and 3rd significant groups of predictors respectively. Mother education and household environment are detected as major significant predictors of post-neonatal mortality. This study shows that MC analysis with or without LR analysis can be applied to detect determinants with rank which help the policy makers taking initiatives on a priority basis. (author)

Similarities and differences regarding changes in attachment preferences and attachment styles in relation to romantic relationship length: longitudinal and concurrent analyses.

Science.gov (United States)

Umemura, Tomotaka; Lacinová, Lenka; Kotrčová, Kristína; Fraley, R Chris

2018-04-01

This study examines whether attachment preferences and attachment styles with different figures (mother, father, romantic partner, and friends) change over the course of a romantic relationship. Study 1 employed a three-wave longitudinal sample of Czech young adults who were currently in a romantic relationship (N = 870; mean age = 21.57; SD = 1.51; 81% females). Multilevel modeling analyses revealed that, as romantic relationships progressed, attachment preferences for romantic partners increased and preferences for friends decreased. However, preferences for the mother or for the father did not change over time. The parallel pattern was found for attachment avoidance; as romantic relationships progressed, attachment avoidance with romantic partners decreased and avoidance with the best friend increased. Avoidance with mother or with father, however, did not change over time. Study 2 employed a cross-sectional international sample (n = 2,593; mean age = 31.99; SD = 12.13; 79% females). Multiple regression analyses replicated the findings of attachment avoidance in the longitudinal data.

Prediction, Regression and Critical Realism

DEFF Research Database (Denmark)

Næss, Petter

2004-01-01

This paper considers the possibility of prediction in land use planning, and the use of statistical research methods in analyses of relationships between urban form and travel behaviour. Influential writers within the tradition of critical realism reject the possibility of predicting social...... phenomena. This position is fundamentally problematic to public planning. Without at least some ability to predict the likely consequences of different proposals, the justification for public sector intervention into market mechanisms will be frail. Statistical methods like regression analyses are commonly...... seen as necessary in order to identify aggregate level effects of policy measures, but are questioned by many advocates of critical realist ontology. Using research into the relationship between urban structure and travel as an example, the paper discusses relevant research methods and the kinds...

Older maternal age is associated with depression, anxiety, and stress symptoms in young adult female offspring.

Science.gov (United States)

Tearne, Jessica E; Robinson, Monique; Jacoby, Peter; Allen, Karina L; Cunningham, Nadia K; Li, Jianghong; McLean, Neil J

2016-01-01

The evidence regarding older parental age and incidence of mood disorder symptoms in offspring is limited, and that which exists is mixed. We sought to clarify these relationships by using data from the Western Australian Pregnancy Cohort (Raine) Study. The Raine Study provided comprehensive data from 2,900 pregnancies, resulting in 2,868 live born children. A total of 1,220 participants completed the short form of the Depression Anxiety Stress Scale (DASS-21) at the 20-year cohort follow-up. We used negative binomial regression analyses with log link and with adjustment for known perinatal risk factors to examine the extent to which maternal and paternal age at childbirth predicted continuous DASS-21 index scores. In the final multivariate models, a maternal age of 30-34 years was associated with significant increases in stress DASS-21 scores in female offspring relative to female offspring of 25- to 29-year-old mothers. A maternal age of 35 years and over was associated with increased scores on all DASS-21 scales in female offspring. Our results indicate that older maternal age is associated with depression, anxiety, and stress symptoms in young adult females. Further research into the mechanisms underpinning this relationship is needed. (c) 2016 APA, all rights reserved.

Dual Regression

OpenAIRE

Spady, Richard; Stouli, Sami

2012-01-01

We propose dual regression as an alternative to the quantile regression process for the global estimation of conditional distribution functions under minimal assumptions. Dual regression provides all the interpretational power of the quantile regression process while avoiding the need for repairing the intersecting conditional quantile surfaces that quantile regression often produces in practice. Our approach introduces a mathematical programming characterization of conditional distribution f...

Influence of regression model and incremental test protocol on the relationship between lactate threshold using the maximal-deviation method and performance in female runners.

Science.gov (United States)

Machado, Fabiana Andrade; Nakamura, Fábio Yuzo; Moraes, Solange Marta Franzói De

2012-01-01

This study examined the influence of the regression model and initial intensity of an incremental test on the relationship between the lactate threshold estimated by the maximal-deviation method and the endurance performance. Sixteen non-competitive, recreational female runners performed a discontinuous incremental treadmill test. The initial speed was set at 7 km · h⁻¹, and increased every 3 min by 1 km · h⁻¹ with a 30-s rest between the stages used for earlobe capillary blood sample collection. Lactate-speed data were fitted by an exponential-plus-constant and a third-order polynomial equation. The lactate threshold was determined for both regression equations, using all the coordinates, excluding the first and excluding the first and second initial points. Mean speed of a 10-km road race was the performance index (3.04 ± 0.22 m · s⁻¹). The exponentially-derived lactate threshold had a higher correlation (0.98 ≤ r ≤ 0.99) and smaller standard error of estimate (SEE) (0.04 ≤ SEE ≤ 0.05 m · s⁻¹) with performance than the polynomially-derived equivalent (0.83 ≤ r ≤ 0.89; 0.10 ≤ SEE ≤ 0.13 m · s⁻¹). The exponential lactate threshold was greater than the polynomial equivalent (P performance index that is independent of the initial intensity of the incremental test and better than the polynomial equivalent.

Intermediate and advanced topics in multilevel logistic regression analysis.

Science.gov (United States)

Austin, Peter C; Merlo, Juan

2017-09-10

Multilevel data occur frequently in health services, population and public health, and epidemiologic research. In such research, binary outcomes are common. Multilevel logistic regression models allow one to account for the clustering of subjects within clusters of higher-level units when estimating the effect of subject and cluster characteristics on subject outcomes. A search of the PubMed database demonstrated that the use of multilevel or hierarchical regression models is increasing rapidly. However, our impression is that many analysts simply use multilevel regression models to account for the nuisance of within-cluster homogeneity that is induced by clustering. In this article, we describe a suite of analyses that can complement the fitting of multilevel logistic regression models. These ancillary analyses permit analysts to estimate the marginal or population-average effect of covariates measured at the subject and cluster level, in contrast to the within-cluster or cluster-specific effects arising from the original multilevel logistic regression model. We describe the interval odds ratio and the proportion of opposed odds ratios, which are summary measures of effect for cluster-level covariates. We describe the variance partition coefficient and the median odds ratio which are measures of components of variance and heterogeneity in outcomes. These measures allow one to quantify the magnitude of the general contextual effect. We describe an R 2 measure that allows analysts to quantify the proportion of variation explained by different multilevel logistic regression models. We illustrate the application and interpretation of these measures by analyzing mortality in patients hospitalized with a diagnosis of acute myocardial infarction. © 2017 The Authors. Statistics in Medicine published by John Wiley & Sons Ltd. © 2017 The Authors. Statistics in Medicine published by John Wiley & Sons Ltd.

Influence of lifestyle factors on long-term sickness absence among female healthcare workers

DEFF Research Database (Denmark)

Quist, Helle Gram; Thomsen, Birthe L; Christensen, Ulla

2014-01-01

BACKGROUND: While previous research has indicated that unhealthy lifestyle is associated with sickness absence, this association may be confounded by occupational class. To avoid this potential confounding, we examined the association between lifestyle factors (smoking, leisure-time physical......-time physical activity (trend test p-value = 0.01), so that increasing physical activity results in decreasing risk of LTSA. CONCLUSION: In female healthcare workers, an unhealthy lifestyle (too high/ too low body mass index, smoking, and low physical activity) is associated with higher risk of LTSA....... environment. Subsequently, they were followed for 12 months in a national register on social transfer payments (DREAM register). Cox's regression analyses, applied to grouped survival data, were used to estimate the prospective association between these lifestyle factors and LTSA. RESULTS: We found...

Cervical Cancer Incidence in Young U.S. Females After Human Papillomavirus Vaccine Introduction.

Science.gov (United States)

Guo, Fangjian; Cofie, Leslie E; Berenson, Abbey B

2018-05-30

Since 2006, human papillomavirus vaccine has been recommended for young females in the U.S. This study aimed to compare cervical cancer incidence among young women before and after the human papillomavirus vaccine was introduced. This cross-sectional study used data from the National Program for Cancer Registries and Surveillance, Epidemiology, and End Results Incidence-U.S. Cancer Statistics 2001-2014 database for U.S. females aged 15-34 years. This study compared the 4-year average annual incidence of invasive cervical cancer in the 4 years before human papillomavirus vaccine was introduced (2003-2006) and the 4 most recent years in the vaccine era (2011-2014). Joinpoint regression models of cervical incidence from 2001 to 2014 were fitted to identify the discrete joints (year) that represent statistically significant changes in the direction of the trend after the introduction of human papillomavirus vaccination in 2006. Data were collected in 2001-2014, released, and analyzed in 2017. The 4-year average annual incidence rates for cervical cancer in 2011-2014 were 29% lower than that in 2003-2006 (6.0 vs 8.4 per 1,000,000 people, rate ratio=0.71, 95% CI=0.64, 0.80) among females aged 15-24 years, and 13.0% lower among females aged 25-34 years. Joinpoint analyses of cervical cancer incidence among females aged 15-24 years revealed a significant joint at 2009 for both squamous cell carcinoma and non-squamous cell carcinoma. Among females aged 25-34 years, there was no significant decrease in cervical cancer incidence after 2006. A significant decrease in the incidence of cervical cancer among young females after the introduction of human papillomavirus vaccine may indicate early effects of human papillomavirus vaccination. Copyright © 2018 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

Emotional control in Chinese female cancer survivors.

Science.gov (United States)

Ho, Rainbow T H; Chan, Cecilia L W; Ho, Samuel M Y

2004-11-01

Chinese persons are not known as strong in expressing emotions, especially negative ones. However, being diagnosed with cancer and going through treatment can be an emotionally traumatic experience and cancer patients are supposed to have a stronger need to express these negative feelings. The control of expression of negative emotions such as anger, anxiety and depression in Chinese female cancer survivors (n=139) was examined in the present study using the Chinese version of the Courtauld Emotional Control Scale (CECS). The reliability, internal consistency and validity of the Chinese CECS were comparable to the original English scale. Correlation analyses suggested that cancer survivors with higher emotional control tended to have higher stress, anxiety and depression levels and to adopt negative coping with cancer. Regression analysis showed that emotional control would positively predict stress level even after the effect of depressed mood was under control. Further investigations are suggested in order to elucidate the causal relationships and specific cultural factors affecting emotional control in Chinese cancer survivors and, most importantly, its effect on health outcomes. Copyright (c) 2004 John Wiley & Sons, Ltd.

The Relative Performance of Female and Male Students in Accounting Principles Classes.

Science.gov (United States)

Bouillon, Marvin L.; Doran, B. Michael

1992-01-01

The performance of female and male students in Accounting Principles (AP) I and II was compared by using multiple regression techniques to assess the incremental explanatory effects of gender. Males significantly outperformed females in AP I, contradicting earlier studies. Similar gender of instructor and student was insignificant. (JOW)

Perceived stress, external locus of control, and social support as predictors of psychological adjustment among female inmates with or without a history of sexual abuse.

Science.gov (United States)

Asberg, Kia; Renk, Kimberly

2014-01-01

Given the growing number of women who are incarcerated across the United States, the current study investigated the relationships among female inmates' perceptions of their own stress, external locus of control (LOC), social support adequacy, and various aspects of psychological functioning. Generally, female inmates with a self-reported history of childhood sexual abuse did not differ from their nonabused counterparts on the variables of interest. Results suggested that female inmates' perceptions of higher stress, a higher degree of external LOC, and inadequate social support correlated with greater symptoms of depression and hopelessness as well as lower self-esteem. In regression analyses, stress and social support were significant predictors for depression and anxiety. In contrast, stress was the only significant predictor of hopelessness and self-esteem. Finally, none of the predictors examined here was significant in the prediction of traumatic stress. Overall, findings suggested the importance of stress and social support in the prediction of female inmates' adjustment, specifically their symptoms of depression and anxiety.

Regression Analyses on the Butterfly Ballot Effect: A Statistical Perspective of the US 2000 Election

Science.gov (United States)

Wu, Dane W.

2002-01-01

The year 2000 US presidential election between Al Gore and George Bush has been the most intriguing and controversial one in American history. The state of Florida was the trigger for the controversy, mainly, due to the use of the misleading "butterfly ballot". Using prediction (or confidence) intervals for least squares regression lines…

Female literacy rate is a better predictor of birth rate and infant mortality rate in India

Directory of Open Access Journals (Sweden)

Suman Saurabh

2013-01-01

Full Text Available Background: Educated women are known to take informed reproductive and healthcare decisions. These result in population stabilization and better infant care reflected by lower birth rates and infant mortality rates (IMRs, respectively. Materials and Methods: Our objective was to study the relationship of male and female literacy rates with crude birth rates (CBRs and IMRs of the states and union territories (UTs of India. The data were analyzed using linear regression. CBR and IMR were taken as the dependent variables; while the overall literacy rates, male, and female literacy rates were the independent variables. Results: CBRs were inversely related to literacy rates (slope parameter = -0.402, P < 0.001. On multiple linear regression with male and female literacy rates, a significant inverse relationship emerged between female literacy rate and CBR (slope = -0.363, P < 0.001, while male literacy rate was not significantly related to CBR (P = 0.674. IMR of the states were also inversely related to their literacy rates (slope = -1.254, P < 0.001. Multiple linear regression revealed a significant inverse relationship between IMR and female literacy (slope = -0.816, P = 0.031, whereas male literacy rate was not significantly related (P = 0.630. Conclusion: Female literacy is relatively highly important for both population stabilization and better infant health.

Sexual initiation and contraceptive use among female adolescents ...

African Journals Online (AJOL)

kemrilib

regression model to quantify the effects of a set of factors on female .... based on a weighing of benefits (such as school fees, .... urban areas are exposed to a more diverse life style .... received money or gift or favours in return for sex.

Predictors of success of external cephalic version and cephalic presentation at birth among 1253 women with non-cephalic presentation using logistic regression and classification tree analyses.

Science.gov (United States)

Hutton, Eileen K; Simioni, Julia C; Thabane, Lehana

2017-08-01

Among women with a fetus with a non-cephalic presentation, external cephalic version (ECV) has been shown to reduce the rate of breech presentation at birth and cesarean birth. Compared with ECV at term, beginning ECV prior to 37 weeks' gestation decreases the number of infants in a non-cephalic presentation at birth. The purpose of this secondary analysis was to investigate factors associated with a successful ECV procedure and to present this in a clinically useful format. Data were collected as part of the Early ECV Pilot and Early ECV2 Trials, which randomized 1776 women with a fetus in breech presentation to either early ECV (34-36 weeks' gestation) or delayed ECV (at or after 37 weeks). The outcome of interest was successful ECV, defined as the fetus being in a cephalic presentation immediately following the procedure, as well as at the time of birth. The importance of several factors in predicting successful ECV was investigated using two statistical methods: logistic regression and classification and regression tree (CART) analyses. Among nulliparas, non-engagement of the presenting part and an easily palpable fetal head were independently associated with success. Among multiparas, non-engagement of the presenting part, gestation less than 37 weeks and an easily palpable fetal head were found to be independent predictors of success. These findings were consistent with results of the CART analyses. Regardless of parity, descent of the presenting part was the most discriminating factor in predicting successful ECV and cephalic presentation at birth. © 2017 Nordic Federation of Societies of Obstetrics and Gynecology.

Female autonomy and reported abortion-seeking in Ghana, West Africa.

Science.gov (United States)

Rominski, Sarah D; Gupta, Mira; Aborigo, Raymond; Adongo, Phillip; Engman, Cyril; Hodgson, Abraham; Moyer, Cheryl

2014-09-01

To investigate factors associated with self-reported pregnancy termination in Ghana and thereby appreciate the correlates of abortion-seeking in order to understand safe abortion care provision. In a retrospective study, data from the Ghana 2008 Demographic and Health Survey were used to investigate factors associated with self-reported pregnancy termination. Variables on an individual and household level were examined by both bivariate analyses and multivariate logistic regression. A five-point autonomy scale was created to explore the role of female autonomy in reported abortion-seeking behavior. Among 4916 women included in the survey, 791 (16.1%) reported having an abortion. Factors associated with abortion-seeking included being older, having attended school, and living in an urban versus a rural area. When entered into a logistic regression model with demographic control variables, every step up the autonomy scale (i.e. increasing autonomy) was associated with a 14.0% increased likelihood of reporting the termination of a pregnancy (P health system barriers might play a role in preventing women from seeking safe abortion services, autonomy on an individual level is also important and needs to be addressed if women are to be empowered to seek safe abortion services. Copyright © 2014 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.

Progression and regression of atherosclerosis in APOE3-Leiden transgenic mice : An immunohistochemical study

NARCIS (Netherlands)

Gijbels, M.J.J.; Cammen, M. van der; Laan, L.J.W. van der; Emeis, J.J.; Havekes, L.M.; Hofker, M.H.; Kraal, G.

1999-01-01

Apolipoprotein E3-Leiden (APOE3-Leiden) transgenic mice develop hyperlipidemia and are highly susceptible to diet-induced atherosclerosis. We have studied the progression and regression of atherosclerosis using immunohistochemistry. Female transgenic mice were fed a moderate fat diet to study

Male and female Ethiopian and Kenyan runners are the fastest and the youngest in both half and full marathon.

Science.gov (United States)

Knechtle, Beat; Nikolaidis, Pantelis T; Onywera, Vincent O; Zingg, Matthias A; Rosemann, Thomas; Rüst, Christoph A

2016-01-01

In major marathon races such as the 'World Marathon Majors', female and male East African runners particularly from Ethiopia and Kenya are the fastest. However, whether this trend appears for female and male Ethiopians and Kenyans at recreational level runners (i.e. races at national level) and in shorter road races (e.g. in half-marathon races) has not been studied yet. Thus, the aim of the present study was to examine differences in the performance and the age of female and male runners from East Africa (i.e. Ethiopians and Kenyans) between half- and full marathons. Data from 508,108 athletes (125,894 female and 328,430 male half-marathoners and 10,205 female and 43,489 male marathoners) originating from 126 countries and competing between 1999 and 2014 in all road-based half-marathons and marathons held in one country (Switzerland) were analysed using Chi square (χ(2)) tests, mixed-effects regression analyses and one-way analyses of variance. In half-marathons, 48 women (0.038 %) and 63 men (0.019 %) were from Ethiopia and 80 women (0.063 %) and 134 men (0.040 %) from Kenya. In marathons, three women (0.029 %) and 15 men (0.034 %) were from Ethiopia and two women (0.019 %) and 33 men (0.075 %) from Kenya. There was no statistically significant association between the nationality of East Africans and the format of a race. In both women and men, the fastest race times in half-marathons and marathons were achieved by East African runners (p marathons and marathons, achieved the fastest race times and were the youngest in both half-marathons and marathons. These findings confirmed in the case of half-marathon the trend previously observed in marathon races for a better performance and a younger age in East African runners from Ethiopia and Kenya.

Geodesic least squares regression for scaling studies in magnetic confinement fusion

International Nuclear Information System (INIS)

Verdoolaege, Geert

2015-01-01

In regression analyses for deriving scaling laws that occur in various scientific disciplines, usually standard regression methods have been applied, of which ordinary least squares (OLS) is the most popular. However, concerns have been raised with respect to several assumptions underlying OLS in its application to scaling laws. We here discuss a new regression method that is robust in the presence of significant uncertainty on both the data and the regression model. The method, which we call geodesic least squares regression (GLS), is based on minimization of the Rao geodesic distance on a probabilistic manifold. We demonstrate the superiority of the method using synthetic data and we present an application to the scaling law for the power threshold for the transition to the high confinement regime in magnetic confinement fusion devices

PSYCHOLOGICAL FEATURES OF CONFLICT BEHAVIOUR AMONG FEMALE INMATES

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Anna Leonidovna Plotnikova

2017-04-01

Full Text Available In this article the results of the research concerning the special features of behaviour in the conflicts among the female inmates are given, psychological features of the female inmates are analysed, their psychological typology is presented, inmates gender differences are characterized as well as psychological reasons of interpersonal conflicts among the female inmates in the correctional facilities, the most conflict categories of female inmates are distinguished. Purpose: revealing of dominant strategies of behaviour in the conflict of the female inmates, specific features of female inmates conflict behaviour according to age and type of committed crime. Method: ascertaining experiment Results: dominant strategies of female inmates conflict behaviour are compromise and adjustment. Areas of use: the penitentiary system.

Beliefs and attitudes of male and female adolescents and the risk of smoking behavior

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K Kasim

2016-01-01

Full Text Available Background: Adolescent smoking relates to numerous risk factors, of which beliefs and attitudes toward smoking may play a role. The study aimed to investigate the association between beliefs and attitudes and the risk of adolescent smoking. Materials and Methods: In a school-based cross-sectional study, 3,400 students were recruited from 34 intermediate and secondary schools in Madinah City, Al Madinah Region, Saudi Arabia. Data about sociodemographics, smoking-related factors, and beliefs and attitudes toward smoking were collected using a valid and reliable self-administered questionnaire. Prevalence of smoking was estimated and the studied beliefs and attitudes were compared by smoking status and sex using appropriate statistical analyses including multivariate logistic regression. Results: Of the 3,322 respondents, 33.02% (38.9% males and 26.4% females were current smokers. Beliefs and attitudes toward smoking significantly differed between smokers and nonsmokers in the studied male and female students. The adjusted risk of smoking was significantly increased among female adolescents who believed that male smokers were more attractive [odds ratio (OR = 2.2; 95% confidence interval (CI = 1.6-2.9] and among male smokers who believed that female smokers are more attractive (OR = 1.7; 95% CI = 1.2-2.2. The risk was also increased among all adolescents who believed that smoking lent comfort in social gatherings. Belief that smoking is harmful, however, was negatively associated with the risk of smoking, particularly among females (OR = 0.55; 95% CI = 0.35-0.91. Conclusions: The study revealed a considerable high prevalence of smoking among male and female adolescents. Addressing the beliefs and knowledge about smoking during childhood is crucial in any antismoking program.

Beliefs and attitudes of male and female adolescents and the risk of smoking behavior.

Science.gov (United States)

Kasim, K; Al-Zalabani, A; Abd El-Moneim, E S; Abd El-Moneim, S

2016-01-01

Adolescent smoking relates to numerous risk factors, of which beliefs and attitudes toward smoking may play a role. The study aimed to investigate the association between beliefs and attitudes and the risk of adolescent smoking. In a school-based cross-sectional study, 3,400 students were recruited from 34 intermediate and secondary schools in Madinah City, Al Madinah Region, Saudi Arabia. Data about sociodemographics, smoking-related factors, and beliefs and attitudes toward smoking were collected using a valid and reliable self-administered questionnaire. Prevalence of smoking was estimated and the studied beliefs and attitudes were compared by smoking status and sex using appropriate statistical analyses including multivariate logistic regression. Of the 3,322 respondents, 33.02% (38.9% males and 26.4% females) were current smokers. Beliefs and attitudes toward smoking significantly differed between smokers and nonsmokers in the studied male and female students. The adjusted risk of smoking was significantly increased among female adolescents who believed that male smokers were more attractive [odds ratio (OR) = 2.2; 95% confidence interval (CI) = 1.6-2.9] and among male smokers who believed that female smokers are more attractive (OR = 1.7; 95% CI = 1.2-2.2). The risk was also increased among all adolescents who believed that smoking lent comfort in social gatherings. Belief that smoking is harmful, however, was negatively associated with the risk of smoking, particularly among females (OR = 0.55; 95% CI = 0.35-0.91). The study revealed a considerable high prevalence of smoking among male and female adolescents. Addressing the beliefs and knowledge about smoking during childhood is crucial in any antismoking program.

Easy methods for extracting individual regression slopes: Comparing SPSS, R, and Excel

Directory of Open Access Journals (Sweden)

Roland Pfister

2013-10-01

Full Text Available Three different methods for extracting coefficientsof linear regression analyses are presented. The focus is on automatic and easy-to-use approaches for common statistical packages: SPSS, R, and MS Excel / LibreOffice Calc. Hands-on examples are included for each analysis, followed by a brief description of how a subsequent regression coefficient analysis is performed.

The analysis of nonstationary time series using regression, correlation and cointegration

DEFF Research Database (Denmark)

Johansen, Søren

2012-01-01

There are simple well-known conditions for the validity of regression and correlation as statistical tools. We analyse by examples the effect of nonstationarity on inference using these methods and compare them to model based inference using the cointegrated vector autoregressive model. Finally we...... analyse some monthly data from US on interest rates as an illustration of the methods...

Regression: A Bibliography.

Science.gov (United States)

Pedrini, D. T.; Pedrini, Bonnie C.

Regression, another mechanism studied by Sigmund Freud, has had much research, e.g., hypnotic regression, frustration regression, schizophrenic regression, and infra-human-animal regression (often directly related to fixation). Many investigators worked with hypnotic age regression, which has a long history, going back to Russian reflexologists.…

The influence of sexual harassment on mental health among female military personnel of the Republic of Korea Armed Forces.

Science.gov (United States)

Kim, Tae Kyung; Lee, H-C; Lee, S G; Han, K-T; Park, E-C

2017-04-01

Reports of sexual harassment are becoming more frequent in Republic of Korea (ROK) Armed Forces. This study aimed to analyse the impact of sexual harassment on mental health among female military personnel of the ROK Armed Forces. Data from the 2014 Military Health Survey were used. Instances of sexual harassment were recorded as 'yes' or 'no'. Analysis of variance (ANOVA) was carried out to compare Kessler Psychological Distress Scale 10 (K-10) scores. Multiple logistic regression analysis was performed to identify associations between sexual harassment and K-10 scores. Among 228 female military personnel, 13 (5.7%) individuals experienced sexual harassment. Multiple logistic regression analysis revealed that sexual harassment had a significantly negative impact on K-10 scores (3.486, psexual harassment were identified in the unmarried (including never-married) group (6.761, pSexual harassment has a negative impact on mental health. Factors associated with worse mental health scores included service classification and length of service. The results provide helpful information with which to develop measures for minimising the negative psychological effects from sexual harassment and promoting sexual harassment prevention policy. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Tutorial on Using Regression Models with Count Outcomes Using R

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A. Alexander Beaujean

2016-02-01

Full Text Available Education researchers often study count variables, such as times a student reached a goal, discipline referrals, and absences. Most researchers that study these variables use typical regression methods (i.e., ordinary least-squares either with or without transforming the count variables. In either case, using typical regression for count data can produce parameter estimates that are biased, thus diminishing any inferences made from such data. As count-variable regression models are seldom taught in training programs, we present a tutorial to help educational researchers use such methods in their own research. We demonstrate analyzing and interpreting count data using Poisson, negative binomial, zero-inflated Poisson, and zero-inflated negative binomial regression models. The count regression methods are introduced through an example using the number of times students skipped class. The data for this example are freely available and the R syntax used run the example analyses are included in the Appendix.

Use of probabilistic weights to enhance linear regression myoelectric control.

Science.gov (United States)

Smith, Lauren H; Kuiken, Todd A; Hargrove, Levi J

2015-12-01

Clinically available prostheses for transradial amputees do not allow simultaneous myoelectric control of degrees of freedom (DOFs). Linear regression methods can provide simultaneous myoelectric control, but frequently also result in difficulty with isolating individual DOFs when desired. This study evaluated the potential of using probabilistic estimates of categories of gross prosthesis movement, which are commonly used in classification-based myoelectric control, to enhance linear regression myoelectric control. Gaussian models were fit to electromyogram (EMG) feature distributions for three movement classes at each DOF (no movement, or movement in either direction) and used to weight the output of linear regression models by the probability that the user intended the movement. Eight able-bodied and two transradial amputee subjects worked in a virtual Fitts' law task to evaluate differences in controllability between linear regression and probability-weighted regression for an intramuscular EMG-based three-DOF wrist and hand system. Real-time and offline analyses in able-bodied subjects demonstrated that probability weighting improved performance during single-DOF tasks (p linear regression control. Use of probability weights can improve the ability to isolate individual during linear regression myoelectric control, while maintaining the ability to simultaneously control multiple DOFs.

Female self-employment and children

NARCIS (Netherlands)

Noseleit, Florian

2014-01-01

Several analyses report a positive correlation between fertility and female self-employment; however, scholars disagree about the direction of this relationship. Knowing about the causal relationship is important because the relevant mechanisms and possible implications differ tremendously. This

Advanced statistics: linear regression, part I: simple linear regression.

Science.gov (United States)

Marill, Keith A

2004-01-01

Simple linear regression is a mathematical technique used to model the relationship between a single independent predictor variable and a single dependent outcome variable. In this, the first of a two-part series exploring concepts in linear regression analysis, the four fundamental assumptions and the mechanics of simple linear regression are reviewed. The most common technique used to derive the regression line, the method of least squares, is described. The reader will be acquainted with other important concepts in simple linear regression, including: variable transformations, dummy variables, relationship to inference testing, and leverage. Simplified clinical examples with small datasets and graphic models are used to illustrate the points. This will provide a foundation for the second article in this series: a discussion of multiple linear regression, in which there are multiple predictor variables.

Resuscitation outcomes of reproductive-age females who experienced out-of-hospital cardiac arrest.

Science.gov (United States)

Hagihara, Akihito; Onozuka, Daisuke; Hasegawa, Manabu; Nagata, Takashi; Abe, Takeru; Nabeshima, Yoshihiro

2017-03-01

Although some studies have shown that women in their reproductive years have better resuscitation outcomes of out-of-hospital cardiac arrest (OHCA), conflicting results and methodological problems have also been noted. Thus, we evaluated the resuscitation outcomes of OHCA of females by age. This was a prospective observational study using registry data from all OHCA cases between 2005 and 2012 in Japan. The subjects were females aged 18-110 years who suffered an out-of-hospital cardiac arrest. Logistic regression analyses were performed using total and propensity-matched patients. There were 381,123 OHCA cases that met the inclusion criteria. Among propensity-matched patients, females aged 18-49 and 50-60 years of age had similar rates of return of spontaneous circulation before hospital arrival and 1-month survival (all p>0.60). In contrast, females aged 18-49 years of age had significantly lower rates of 1-month survival with minimal neurological impairment than did females aged 50-60 years of age (after adjusting for selected variables: Cerebral Performance Category scale 1 or 2 (CPC (1, 2)), OR=0.45, p=0.020; Overall Performance Category scale 1 or 2 (OPC (1, 2)): OR=0.42, p= 0.014; after adjustment for all variables: CPC (1, 2), OR=0.27, p= 0.008; OPC (1, 2), OR=0.29, p=0.009). Women of reproductive age did not show improved resuscitation outcomes in OHCA. Additionally, women in their reproductive years showed worse neurological outcomes one month after the event, which may be explained by the negative effects of estrogen. These findings need to be verified in further studies.

Pre-vaccination care-seeking in females reporting severe adverse reactions to HPV vaccine. A registry based case-control study

DEFF Research Database (Denmark)

Mølbak, Kåre; Hansen, Niels Dalum; Valentiner-Branth, Palle

2016-01-01

to the DMA of suspected severe adverse reactions.We selected controls without reports of adverse reactions from the Danish vaccination registry and matched by year of vaccination, age of vaccination, and municipality, and obtained from the Danish National Patient Registry and The National Health Insurance...... vaccination programme has declined. The aim of the present study was to determine health care-seeking prior to the first HPV vaccination among females who suspected adverse reactions to HPV vaccine. Methods In this registry-based case-control study, we included as cases vaccinated females with reports...... Service Register the history of health care usage two years prior to the first vaccine. We analysed the data by logistic regression while adjusting for the matching variables. Results The study included 316 cases who received first HPV vaccine between 2006 and 2014. Age range of cases was 11 to 52 years...

Genome-wide Association Studies for Female Fertility Traits in Chinese and Nordic Holsteins.

Science.gov (United States)

Liu, Aoxing; Wang, Yachun; Sahana, Goutam; Zhang, Qin; Liu, Lin; Lund, Mogens Sandø; Su, Guosheng

2017-08-16

Reduced female fertility could cause considerable economic loss and has become a worldwide problem in the modern dairy industry. The objective of this study was to detect quantitative trait loci (QTL) for female fertility traits in Chinese and Nordic Holsteins using various strategies. First, single-trait association analyses were performed for female fertility traits in Chinese and Nordic Holsteins. Second, the SNPs with P-value Nordic Holsteins. Third, the summary statistics from single-trait association analyses were combined into meta-analyses to: (1) identify common QTL for multiple fertility traits within each Holstein population; (2) detect SNPs which were associated with a female fertility trait across two Holstein populations. A large numbers of QTL were discovered or confirmed for female fertility traits. The QTL segregating at 31.4~34.1 Mb on BTA13, 48.3~51.9 Mb on BTA23 and 34.0~37.6 Mb on BTA28 shared between Chinese and Nordic Holsteins were further ascertained using a validation approach and meta-analyses. Furthermore, multiple novel variants identified in Chinese Holsteins were validated with Nordic data as well as meta-analyses. The genes IL6R, SLC39A12, CACNB2, ZEB1, ZMIZ1 and FAM213A were concluded to be strong candidate genes for female fertility in Holsteins.

Radiation exposure analysis of female nuclear medicine radiation workers

Energy Technology Data Exchange (ETDEWEB)

Lee, Ju Young [Dept. of Biomedical Engineering Graduate School, Chungbuk National University, Cheongju (Korea, Republic of); Park, Hoon Hee [Dept. of Radiological Technologist, Shingu College, Sungnam (Korea, Republic of)

2016-06-15

In this study, radiation workers who work in nuclear medicine department were analyzed to find the cause of differences of radiation exposure from General Characteristic, Knowledge, Recognition and Conduct, especially females working on nuclear medicine radiation, in order to pave the way for positive defense against radiation exposure. The subjects were 106 radiation workers who were divided into two groups of sixty-four males and forty-two females answered questions about their General Characteristic, Knowledge, Recognition, Conduct, and radiation exposure dose which was measured by TLD (Thermo Luminescence Dosimeter). The results of the analysis revealed that as the higher score of knowledge and conduct was shown, the radiation exposure decreased in female groups, and as the higher score of conduct was shown, the radiation exposure decreased in male groups. In the correlation analysis of female groups, the non-experienced in pregnancy showed decreasing amount of radiation exposure as the score of knowledge and conduct was higher and the experienced in pregnancy showed decreasing amount of radiation exposure as the score of recognition and conduct was higher. In the regression analysis on related factors of radiation exposure dose of nuclear medicine radiation workers, the gender caused the meaningful result and the amount of radiation exposure of female groups compared to male groups. In the regression analysis on related factors of radiation exposure dose of female groups, the factor of conduct showed a meaningful result and the amount of radiation exposure of the experienced in pregnancy was lower compared to the non-experienced. The conclusion of this study revealed that radiation exposure of female groups was lower than that of male groups. Therefore, male groups need to more actively defend themselves against radiation exposure. Among the female groups, the experienced in pregnancy who have an active defense tendency showed a lower radiation exposure. Thus

Radiation exposure analysis of female nuclear medicine radiation workers

International Nuclear Information System (INIS)

Lee, Ju Young; Park, Hoon Hee

2016-01-01

In this study, radiation workers who work in nuclear medicine department were analyzed to find the cause of differences of radiation exposure from General Characteristic, Knowledge, Recognition and Conduct, especially females working on nuclear medicine radiation, in order to pave the way for positive defense against radiation exposure. The subjects were 106 radiation workers who were divided into two groups of sixty-four males and forty-two females answered questions about their General Characteristic, Knowledge, Recognition, Conduct, and radiation exposure dose which was measured by TLD (Thermo Luminescence Dosimeter). The results of the analysis revealed that as the higher score of knowledge and conduct was shown, the radiation exposure decreased in female groups, and as the higher score of conduct was shown, the radiation exposure decreased in male groups. In the correlation analysis of female groups, the non-experienced in pregnancy showed decreasing amount of radiation exposure as the score of knowledge and conduct was higher and the experienced in pregnancy showed decreasing amount of radiation exposure as the score of recognition and conduct was higher. In the regression analysis on related factors of radiation exposure dose of nuclear medicine radiation workers, the gender caused the meaningful result and the amount of radiation exposure of female groups compared to male groups. In the regression analysis on related factors of radiation exposure dose of female groups, the factor of conduct showed a meaningful result and the amount of radiation exposure of the experienced in pregnancy was lower compared to the non-experienced. The conclusion of this study revealed that radiation exposure of female groups was lower than that of male groups. Therefore, male groups need to more actively defend themselves against radiation exposure. Among the female groups, the experienced in pregnancy who have an active defense tendency showed a lower radiation exposure. Thus

The Analysis of Nonstationary Time Series Using Regression, Correlation and Cointegration

Directory of Open Access Journals (Sweden)

Søren Johansen

2012-06-01

Full Text Available There are simple well-known conditions for the validity of regression and correlation as statistical tools. We analyse by examples the effect of nonstationarity on inference using these methods and compare them to model based inference using the cointegrated vector autoregressive model. Finally we analyse some monthly data from US on interest rates as an illustration of the methods.

Tools to support interpreting multiple regression in the face of multicollinearity.

Science.gov (United States)

Kraha, Amanda; Turner, Heather; Nimon, Kim; Zientek, Linda Reichwein; Henson, Robin K

2012-01-01

While multicollinearity may increase the difficulty of interpreting multiple regression (MR) results, it should not cause undue problems for the knowledgeable researcher. In the current paper, we argue that rather than using one technique to investigate regression results, researchers should consider multiple indices to understand the contributions that predictors make not only to a regression model, but to each other as well. Some of the techniques to interpret MR effects include, but are not limited to, correlation coefficients, beta weights, structure coefficients, all possible subsets regression, commonality coefficients, dominance weights, and relative importance weights. This article will review a set of techniques to interpret MR effects, identify the elements of the data on which the methods focus, and identify statistical software to support such analyses.

Testing and Modeling Fuel Regression Rate in a Miniature Hybrid Burner

Directory of Open Access Journals (Sweden)

Luciano Fanton

2012-01-01

Full Text Available Ballistic characterization of an extended group of innovative HTPB-based solid fuel formulations for hybrid rocket propulsion was performed in a lab-scale burner. An optical time-resolved technique was used to assess the quasisteady regression history of single perforation, cylindrical samples. The effects of metalized additives and radiant heat transfer on the regression rate of such formulations were assessed. Under the investigated operating conditions and based on phenomenological models from the literature, analyses of the collected experimental data show an appreciable influence of the radiant heat flux from burnt gases and soot for both unloaded and loaded fuel formulations. Pure HTPB regression rate data are satisfactorily reproduced, while the impressive initial regression rates of metalized formulations require further assessment.

Female ever-smoking, education, emancipation and economic development in 19 European countries

DEFF Research Database (Denmark)

Schaap, Maartje M; Kunst, Anton E; Leinsalu, Mall

2009-01-01

Large differences in ever-smoking rates among women are found between countries and socio-economic groups. This study examined the socio-economic inequalities in female ever-smoking rates in 19 European countries, and explored the association between cross-national differences in these inequalities...... of current and former smokers of the total survey population. A Relative Index of Inequality was estimated for women in the three age groups to measure the magnitude of educational differences. In regression analyses the association of ever-smoking rates of women age 25-39 years with the gross domestic...... product (GDP) and the Gender Empowerment Measure (GEM) was explored. Less educated women aged 25-39 years were more likely to have ever smoked than more educated women in all countries, except Portugal. In the age groups 40-59 years the educational pattern differed between countries. Women aged 60+ years...

Differential item functioning (DIF) analyses of health-related quality of life instruments using logistic regression

DEFF Research Database (Denmark)

Scott, Neil W; Fayers, Peter M; Aaronson, Neil K

2010-01-01

Differential item functioning (DIF) methods can be used to determine whether different subgroups respond differently to particular items within a health-related quality of life (HRQoL) subscale, after allowing for overall subgroup differences in that scale. This article reviews issues that arise ...... when testing for DIF in HRQoL instruments. We focus on logistic regression methods, which are often used because of their efficiency, simplicity and ease of application....

Iron status of toddlers, nonpregnant females, and pregnant females in the United States.

Science.gov (United States)

Gupta, Priya M; Hamner, Heather C; Suchdev, Parminder S; Flores-Ayala, Rafael; Mei, Zuguo

2017-12-01

Background: Total-body iron stores (TBI), which are calculated from serum ferritin and soluble transferrin receptor concentrations, can be used to assess the iron status of populations in the United States. Objective: This analysis, developed to support workshop discussions, describes the distribution of TBI and the prevalence of iron deficiency (ID) and ID anemia (IDA) among toddlers, nonpregnant females, and pregnant females. Design: We analyzed data from NHANES; toddlers aged 12-23 mo (NHANES 2003-2010), nonpregnant females aged 15-49 y (NHANES 2007-2010), and pregnant females aged 12-49 y (NHANES 1999-2010). We used SAS survey procedures to plot distributions of TBI and produce prevalence estimates of ID and IDA for each target population. All analyses were weighted to account for the complex survey design. Results: According to these data, ID prevalences (± SEs) were 15.1% ± 1.7%, 10.4% ± 0.5%, and 16.3% ± 1.3% in toddlers, nonpregnant females, and pregnant females, respectively. ID prevalence in pregnant females increased significantly with each trimester (5.3% ± 1.5%, 12.7% ± 2.3%, and 27.5% ± 3.5% in the first, second, and third trimesters, respectively). Racial disparities in the prevalence of ID among both nonpregnant and pregnant females exist, with Mexican American and non-Hispanic black females at greater risk of ID than non-Hispanic white females. IDA prevalence was 5.0% ± 0.4% and 2.6% ± 0.7% in nonpregnant and pregnant females, respectively. Conclusions: Available nationally representative data suggest that ID and IDA remain a concern in the United States. Estimates of iron-replete status cannot be made at this time in the absence of established cutoffs for iron repletion based on TBI. The study was registered at clinicaltrials.gov as NCT03274726. © 2017 American Society for Nutrition.

Queering gender in contemporary female Bildung narrative

Directory of Open Access Journals (Sweden)

Šnircová Soňa

2015-09-01

Full Text Available The paper explores, in the context of feminist discussions about the Bildungsroman, a contemporary British novel that offers shocking images of female coming of age at the turn of the millennium. Queering gender and introducing male elements into the heroine’s process of maturation, the analysed novel appears to raise questions about the continuous relevance of the feminist distinction between male and female version of the genre. The paper however argues that although significantly rewriting both female Bildung and pornographic narratives, Helen Walsh’s Brass can still be read as a variation of the female Bildungsroman and an example of its contemporary developments.

The impact of global signal regression on resting state correlations: are anti-correlated networks introduced?

Science.gov (United States)

Murphy, Kevin; Birn, Rasmus M; Handwerker, Daniel A; Jones, Tyler B; Bandettini, Peter A

2009-02-01

Low-frequency fluctuations in fMRI signal have been used to map several consistent resting state networks in the brain. Using the posterior cingulate cortex as a seed region, functional connectivity analyses have found not only positive correlations in the default mode network but negative correlations in another resting state network related to attentional processes. The interpretation is that the human brain is intrinsically organized into dynamic, anti-correlated functional networks. Global variations of the BOLD signal are often considered nuisance effects and are commonly removed using a general linear model (GLM) technique. This global signal regression method has been shown to introduce negative activation measures in standard fMRI analyses. The topic of this paper is whether such a correction technique could be the cause of anti-correlated resting state networks in functional connectivity analyses. Here we show that, after global signal regression, correlation values to a seed voxel must sum to a negative value. Simulations also show that small phase differences between regions can lead to spurious negative correlation values. A combination breath holding and visual task demonstrates that the relative phase of global and local signals can affect connectivity measures and that, experimentally, global signal regression leads to bell-shaped correlation value distributions, centred on zero. Finally, analyses of negatively correlated networks in resting state data show that global signal regression is most likely the cause of anti-correlations. These results call into question the interpretation of negatively correlated regions in the brain when using global signal regression as an initial processing step.

[Does self-esteem affect body dissatisfaction levels in female adolescents?].

Science.gov (United States)

Fortes, Leonardo de Sousa; Cipriani, Flávia Marcele; Coelho, Fernanda Dias; Paes, Santiago Tavares; Ferreira, Maria Elisa Caputo

2014-09-01

To evaluate the influence of self-esteem on levels of body dissatisfaction among adolescent females. A group of 397 adolescents aged 12 to 17 years were enrolled in the study. The Body Shape Questionnaire (BSQ) was applied to assess body dissatisfaction. The Rosenberg Self-Esteem Scale was used to assess self-esteem. Weight, height, and skinfold thickness were also measured. These anthropometric data were controlled in the statistical analyses. The multiple regression model indicated influence of "positive self-esteem" (R(2)=0.16; p=0.001) and "negative self-esteem" (R(2)=0.23; p=0.001) subscales on the BSQ scores. Univariate analysis of covariance demonstrated differences in BSQ scores (p=0.001) according to groups of self-esteem. It was concluded that self-esteem influenced body dissatisfaction in adolescent girls from Juiz de Fora, MG. Copyright © 2014 Sociedade de Pediatria de São Paulo. Publicado por Elsevier Editora Ltda. All rights reserved.

Female Surgeons as Counter Stereotype: The Impact of Gender Perceptions on Trainee Evaluations of Physician Faculty.

Science.gov (United States)

Fassiotto, Magali; Li, Jie; Maldonado, Yvonne; Kothary, Nishita

2018-02-02

Similar to women in Science, Technology, Engineering and Mathematics disciplines, women in medicine are subject to negative stereotyping when they do not adhere to their sex-role expectations. These biases may vary by specialty, largely dependent on the gender's representation in that specialty. Thus, females in male-dominated surgical specialties are especially at risk of stereotype threat. Herein, we present the role of gender expectations using trainee evaluations of physician faculty at a single academic center, over a 5-year period (2010-2014). Using Graduate Medical Education evaluation data of physician faculty from MedHub, we examined the differences in evaluation scores for male and female physicians within specialties that have traditionally had low female representation (e.g., surgical fields) compared to those with average or high female representation (e.g., pediatrics). Stanford Medicine residents and fellows' MedHub ratings of their physician faculty from 2010 to 2014. A total of 3648 evaluations across 1066 physician faculty. Overall, female physicians received lower median scores than their male counterparts across all specialties. When using regression analyses controlling for race, age, rank, and specialty-specific characteristics, the negative effect persists only for female physicians in specialties with low female representation. This finding suggests that female physicians in traditionally male-dominated specialties may face different criteria based on sex-role expectations when being evaluated by trainees. As trainee evaluations play an important role in career advancement decisions, dictate perceptions of quality within academic medical centers and affect overall job satisfaction, we propose that these differences in evaluations based merely on gender stereotypes could account, in part, for the narrowing pipeline of women promoted to higher ranks in academic medicine. Copyright © 2018 Association of Program Directors in Surgery. Published

Black Female Homicide Offenders and Victims: Are They from the Same Population?

Science.gov (United States)

McClain, Paula D.

1982-01-01

Explores the social and environmental characteristics of Black female homicide victims and offenders. Assembled data on 661 Black female homicide victims and 119 Black female homicide offenders. Analyses indicated that Black female homicide victims and offenders exhibit low socioeconomic status and essentially similar behavior patterns. (Author)

Factors Contributing to Pelvis Instability in Female Adolescent Athletes During Unilateral Repeated Partial Squat Activity

Science.gov (United States)

Scarborough, Donna Moxley; Linderman, Shannon; Berkson, Eric M.; Oh, Luke S.

2017-01-01

Objectives: Unilateral partial squat tasks are often used to assess athletes’ lower extremity (LE) neuromuscular control. Single squat biomechanics such as lateral drop of the non-stance limb’s pelvis have been linked to knee injury risk. Yet, there are limited studies on the factors contributing to pelvic instability during the unilateral partial squat such as anatomical alignment of the knee and hip strength. The purpose of this study was 1) to assess the influence of leg dominance on pelvic drop among female athletes during the repeated unilateral partial squat activity and 2) to investigate the contributions that lower limb kinematics and hip strength have on pelvis drop. Methods: 42 female athletes (27= softball pitchers, 15=gymnasts, avg age=16.48 ± 2.54 years) underwent lower limb assessment. The quadriceps angle (Q angle) and the average of 3 trials for hip abduction and extension strength (handheld dynamometer measurements) were used for analyses. 3D biomechanical analysis of the repeated unilateral partial squat activity followed using a 20 motion capture camera system which created a 15 segment model of each subject. The subject stood on one leg at the lateral edge of a 17.78 cm box with hands placed on the hips and squatted so that the free hanging contralateral limb came as close to the ground without contact for 5 continuous repetitions. One trial for each limb was performed. Peak pelvic drop and ankle, knee and hip angles and torques (normalized by weight) at this time point were calculated using Visual 3D (C-Motion) biomechanical software. Paired T-test, Spearman correlations and multiple regression model statistical analyses were performed. Results: Peak pelvic drop during the unilateral partial squat did not differ significantly on the basis of limb dominance (p=0.831, Dom: -3.40 ± 5.10° , ND: -3.46 ± 4.44°). Peak pelvic drop displayed a Spearman correlation with the functional measure of hip abduction/adduction (ABD/ADD) angle (rs= 0

An Original Stepwise Multilevel Logistic Regression Analysis of Discriminatory Accuracy

DEFF Research Database (Denmark)

Merlo, Juan; Wagner, Philippe; Ghith, Nermin

2016-01-01

BACKGROUND AND AIM: Many multilevel logistic regression analyses of "neighbourhood and health" focus on interpreting measures of associations (e.g., odds ratio, OR). In contrast, multilevel analysis of variance is rarely considered. We propose an original stepwise analytical approach that disting...

A regressive formula of perversity: Wertham and the women of comics.

Science.gov (United States)

Tilley, Carol L

2018-04-25

This essay serves as a close reading of psychiatrist Fredric Wertham's 1950s descriptions and critiques of female comics characters. I draw on archival sources as well as relevant texts in the study of gender and sexuality. Additionally, I integrate ideas from two of his close associates, folklorist Gershon Legman and psychiatrist Hilde Mosse, whose contributions to Seduction of the Innocent are woven-often invisibly-throughout that text. The character of Wonder Woman serves as a touchstone, but other provocative female figures that Wertham found objectionable in mid-twentieth-century comics accompany her. My goal is to illuminate Wertham's understanding of what he viewed as the "regressive formula of perversity" enacted through women's representations in comics, particularly those female characters who played active roles. Although not all of these concerns are tied to lesbian identity, they do all touch on broader notions of queerness vis-à-vis deviant sexual and gender expression.

A Comparison of Anthropometric and Training Characteristics between Female and Male Half-Marathoners and the Relationship to Race Time.

Science.gov (United States)

Friedrich, Miriam; Rüst, Christoph A; Rosemann, Thomas; Knechtle, Patrizia; Barandun, Ursula; Lepers, Romuald; Knechtle, Beat

2014-03-01

Lower limb skin-fold thicknesses have been differentially associated with sex in elite runners. Front thigh and medial calf skin-fold appear to be related to 1,500m and 10,000m time in men but 400m time in women. The aim of the present study was to compare anthropometric and training characteristics in recreational female and male half-marathoners. The association between both anthropometry and training characteristics and race time was investigated in 83 female and 147 male recreational half marathoners using bi- and multi-variate analyses. In men, body fat percentage (β=0.6), running speed during training (β=-3.7), and body mass index (β=1.9) were related to half-marathon race time after multi-variate analysis. After exclusion of body mass index, r (2) decreased from 0.51 to 0.49, but body fat percentage (β=0.8) and running speed during training (β=-4.1) remained predictive. In women, body fat percentage (β=0.75) and speed during training (β=-6.5) were related to race time (r (2) =0.73). For women, the exclusion of body mass index had no consequence on the predictive variables for half-marathon race time. To summarize, in both female and male recreational half-marathoners, both body fat percentage and running speed during training sessions were related to half-marathon race times when corrected with co-variates after multi-variate regression analyses.

Do knowledge and cultural perceptions of modern female contraceptives predict male involvement in Ayete, Nigeria?

Science.gov (United States)

Sanusi, A; Akinyemi, Oluwaseun O; Onoviran, Oghemetega O

2014-12-01

Male involvement is crucial to female contraceptive use. This study examined how male knowledge and cultural perceptions of modern female contraceptives influence involvement in contraceptive use. A cross-sectional survey of 389 men from Ayete, Nigeria was used to regress a continuous male involvement score on demographic variables, knowledge of at least one method of modern female contraception and a scored male perception variable using Ordinary Least Squares regression. Controlling for perception, the knowledge of at least one method of modern female contraception was not significantly associated with a change in male involvement (p=0.264). Increasing positive perception was associated with higher male involvement scores (p=0.001). Higher educated males, those with a current desire to have children and males whose partners were currently using a method had greater male involvement scores (pcultural perceptions, in addition to providing in-depth knowledge of contraceptive methods.

Ordinary least square regression, orthogonal regression, geometric mean regression and their applications in aerosol science

International Nuclear Information System (INIS)

Leng Ling; Zhang Tianyi; Kleinman, Lawrence; Zhu Wei

2007-01-01

Regression analysis, especially the ordinary least squares method which assumes that errors are confined to the dependent variable, has seen a fair share of its applications in aerosol science. The ordinary least squares approach, however, could be problematic due to the fact that atmospheric data often does not lend itself to calling one variable independent and the other dependent. Errors often exist for both measurements. In this work, we examine two regression approaches available to accommodate this situation. They are orthogonal regression and geometric mean regression. Comparisons are made theoretically as well as numerically through an aerosol study examining whether the ratio of organic aerosol to CO would change with age

Interpreting Multiple Linear Regression: A Guidebook of Variable Importance

Science.gov (United States)

Nathans, Laura L.; Oswald, Frederick L.; Nimon, Kim

2012-01-01

Multiple regression (MR) analyses are commonly employed in social science fields. It is also common for interpretation of results to typically reflect overreliance on beta weights, often resulting in very limited interpretations of variable importance. It appears that few researchers employ other methods to obtain a fuller understanding of what…

Evaluation of Earning Performance of Female Owned Leather ...

African Journals Online (AJOL)

The tools for data analyses were descriptive statistics, income statement and an econometric model involving Ordinary Least Square regression analyses. The earning performance evaluation indicated that the enterprises have performed creditably considering the value of the gross margin analysis which is high and gross ...

Estimating the exceedance probability of rain rate by logistic regression

Science.gov (United States)

Chiu, Long S.; Kedem, Benjamin

1990-01-01

Recent studies have shown that the fraction of an area with rain intensity above a fixed threshold is highly correlated with the area-averaged rain rate. To estimate the fractional rainy area, a logistic regression model, which estimates the conditional probability that rain rate over an area exceeds a fixed threshold given the values of related covariates, is developed. The problem of dependency in the data in the estimation procedure is bypassed by the method of partial likelihood. Analyses of simulated scanning multichannel microwave radiometer and observed electrically scanning microwave radiometer data during the Global Atlantic Tropical Experiment period show that the use of logistic regression in pixel classification is superior to multiple regression in predicting whether rain rate at each pixel exceeds a given threshold, even in the presence of noisy data. The potential of the logistic regression technique in satellite rain rate estimation is discussed.

Linear regression and the normality assumption.

Science.gov (United States)

Schmidt, Amand F; Finan, Chris

2017-12-16

Researchers often perform arbitrary outcome transformations to fulfill the normality assumption of a linear regression model. This commentary explains and illustrates that in large data settings, such transformations are often unnecessary, and worse may bias model estimates. Linear regression assumptions are illustrated using simulated data and an empirical example on the relation between time since type 2 diabetes diagnosis and glycated hemoglobin levels. Simulation results were evaluated on coverage; i.e., the number of times the 95% confidence interval included the true slope coefficient. Although outcome transformations bias point estimates, violations of the normality assumption in linear regression analyses do not. The normality assumption is necessary to unbiasedly estimate standard errors, and hence confidence intervals and P-values. However, in large sample sizes (e.g., where the number of observations per variable is >10) violations of this normality assumption often do not noticeably impact results. Contrary to this, assumptions on, the parametric model, absence of extreme observations, homoscedasticity, and independency of the errors, remain influential even in large sample size settings. Given that modern healthcare research typically includes thousands of subjects focusing on the normality assumption is often unnecessary, does not guarantee valid results, and worse may bias estimates due to the practice of outcome transformations. Copyright © 2017 Elsevier Inc. All rights reserved.

Female ethnicity: Understanding Muslim immigrant businesswomen in the Netherlands

NARCIS (Netherlands)

Essers, C.; Benschop, Y.W.M.; Doorewaard, J.A.C.M.

2010-01-01

Building on theories of intersectionality, in this article we develop the concept of female ethnicity in order to understand the meanings of femininity for Muslim immigrant businesswomen in the context of entrepreneurship. Through the notion of female ethnicity we analyse four life stories and

Polynomial regression analysis and significance test of the regression function

International Nuclear Information System (INIS)

Gao Zhengming; Zhao Juan; He Shengping

2012-01-01

In order to analyze the decay heating power of a certain radioactive isotope per kilogram with polynomial regression method, the paper firstly demonstrated the broad usage of polynomial function and deduced its parameters with ordinary least squares estimate. Then significance test method of polynomial regression function is derived considering the similarity between the polynomial regression model and the multivariable linear regression model. Finally, polynomial regression analysis and significance test of the polynomial function are done to the decay heating power of the iso tope per kilogram in accord with the authors' real work. (authors)

Casual Attributions of Adolescent Females in a Masculine Domain.

Science.gov (United States)

Krauser, Barbara Z.; Ballif, Bonnie L.

Achievement attributions of adolescent females in the masculine domain of mathematics were investigated in relation to self-schemas for gender, expectancy of success, and mathematics achievement. The most important findings revealed by multiple regression analysis were that mathematics achievement and the self-schema for masculinity predicted…

Estimation of stature from the foot and its segments in a sub-adult female population of North India

Directory of Open Access Journals (Sweden)

Krishan Kewal

2011-11-01

Full Text Available Abstract Background Establishing personal identity is one of the main concerns in forensic investigations. Estimation of stature forms a basic domain of the investigation process in unknown and co-mingled human remains in forensic anthropology case work. The objective of the present study was to set up standards for estimation of stature from the foot and its segments in a sub-adult female population. Methods The sample for the study constituted 149 young females from the Northern part of India. The participants were aged between 13 and 18 years. Besides stature, seven anthropometric measurements that included length of the foot from each toe (T1, T2, T3, T4, and T5 respectively, foot breadth at ball (BBAL and foot breadth at heel (BHEL were measured on both feet in each participant using standard methods and techniques. Results The results indicated that statistically significant differences (p p-value Conclusions The present study concluded that foot measurements have a strong relationship with stature in the sub-adult female population of North India. Hence, the stature of an individual can be successfully estimated from the foot and its segments using different regression models derived in the study. The regression models derived in the study may be applied successfully for the estimation of stature in sub-adult females, whenever foot remains are brought for forensic examination. Stepwise multiple regression models tend to estimate stature more accurately than linear regression models in female sub-adults.

The best of both worlds: Phylogenetic eigenvector regression and mapping

Directory of Open Access Journals (Sweden)

José Alexandre Felizola Diniz Filho

2015-09-01

Full Text Available Eigenfunction analyses have been widely used to model patterns of autocorrelation in time, space and phylogeny. In a phylogenetic context, Diniz-Filho et al. (1998 proposed what they called Phylogenetic Eigenvector Regression (PVR, in which pairwise phylogenetic distances among species are submitted to a Principal Coordinate Analysis, and eigenvectors are then used as explanatory variables in regression, correlation or ANOVAs. More recently, a new approach called Phylogenetic Eigenvector Mapping (PEM was proposed, with the main advantage of explicitly incorporating a model-based warping in phylogenetic distance in which an Ornstein-Uhlenbeck (O-U process is fitted to data before eigenvector extraction. Here we compared PVR and PEM in respect to estimated phylogenetic signal, correlated evolution under alternative evolutionary models and phylogenetic imputation, using simulated data. Despite similarity between the two approaches, PEM has a slightly higher prediction ability and is more general than the original PVR. Even so, in a conceptual sense, PEM may provide a technique in the best of both worlds, combining the flexibility of data-driven and empirical eigenfunction analyses and the sounding insights provided by evolutionary models well known in comparative analyses.

Reduced Rank Regression

DEFF Research Database (Denmark)

Johansen, Søren

2008-01-01

The reduced rank regression model is a multivariate regression model with a coefficient matrix with reduced rank. The reduced rank regression algorithm is an estimation procedure, which estimates the reduced rank regression model. It is related to canonical correlations and involves calculating...

Female Institutional Directors on Boards and Firm Value

OpenAIRE

Pucheta Martínez, María Consuelo; Bel Oms, Inmaculada; Olcina Sempere, Gustau

2016-01-01

The aim of this research is to examine what impact female institutional directors on boards have on corporate performance. Previous research shows that institutional female directors cannot be considered as a homogeneous group since they represent investors who may or may not maintain business relations with the companies on whose corporate boards they sit. Thus, it is not only the effect of female institutional directors as a whole on firm value that has been analysed, but also the impact of...

Prediction of radiation levels in residences: A methodological comparison of CART [Classification and Regression Tree Analysis] and conventional regression

International Nuclear Information System (INIS)

Janssen, I.; Stebbings, J.H.

1990-01-01

In environmental epidemiology, trace and toxic substance concentrations frequently have very highly skewed distributions ranging over one or more orders of magnitude, and prediction by conventional regression is often poor. Classification and Regression Tree Analysis (CART) is an alternative in such contexts. To compare the techniques, two Pennsylvania data sets and three independent variables are used: house radon progeny (RnD) and gamma levels as predicted by construction characteristics in 1330 houses; and ∼200 house radon (Rn) measurements as predicted by topographic parameters. CART may identify structural variables of interest not identified by conventional regression, and vice versa, but in general the regression models are similar. CART has major advantages in dealing with other common characteristics of environmental data sets, such as missing values, continuous variables requiring transformations, and large sets of potential independent variables. CART is most useful in the identification and screening of independent variables, greatly reducing the need for cross-tabulations and nested breakdown analyses. There is no need to discard cases with missing values for the independent variables because surrogate variables are intrinsic to CART. The tree-structured approach is also independent of the scale on which the independent variables are measured, so that transformations are unnecessary. CART identifies important interactions as well as main effects. The major advantages of CART appear to be in exploring data. Once the important variables are identified, conventional regressions seem to lead to results similar but more interpretable by most audiences. 12 refs., 8 figs., 10 tabs

Sexual satisfaction in females with premenstrual symptoms.

Science.gov (United States)

Nowosielski, Krzysztof; Drosdzol, Agnieszka; Skrzypulec, Violetta; Plinta, Ryszard

2010-11-01

The impact of premenstrual symptoms, such as the premenstrual syndrome (PMS) and the premenstrual dysphoric disorder (PMDD), on sexual satisfaction, sexual distress, and sexual behaviors has not yet been established. To assess the correlates and risk factors of sexual satisfaction and to evaluate sexual behaviors among Polish women with premenstrual symptoms. 2,500 females, aged 18 to 45 years, from the Upper Silesian region of Poland were eligible for the questionnaire-based, prospective population study. All the inclusion criteria were met by 1,540 women who constituted the final study group. The participants were further divided into two subgroups: PMS+ (749 females) and PMS- (791 healthy subjects). Two additional subgroups were created: PMDD+ encompassing 32 subjects diagnosed with PMDD, and PMDD- comprising 32 healthy women, matched to the PMDD+ females for age, marital status, education level, employment status, place of living, and body mass index. A multiple logistic regression analysis was performed to evaluate the influence of PMS on sexual satisfaction and adjust for potential confounders. To evaluate risk factors for sexual dissatisfaction in a population of Polish females of reproductive age, diagnosed with PMS and PMDD. Women from the PMS+ group were less sexually satisfied than PMS- (77.73% vs. 88.66%, P=0.001) and reported more sexual distress (28.65% vs. 15.24%, P=0.001). There were no significant differences in sexual satisfaction between PMDD- and PMDD+. Sexual satisfaction correlated positively with a higher frequency of sexual intercourses and a higher level of education. The presence of PMS correlated negatively with sexual satisfaction, even after adjusting for potential confounders in the multivariate logistic regression model (odds ratio=0.48; confidence interval: 0.26-0.89; P=0.02). The presence of PMS is a risk factor for sexual dissatisfaction in Polish women of reproductive age. © 2010 International Society for Sexual Medicine.

Logistic Regression Analysis of Operational Errors and Routine Operations Using Sector Characteristics

National Research Council Canada - National Science Library

Pfleiderer, Elaine M; Scroggins, Cheryl L; Manning, Carol A

2009-01-01

Two separate logistic regression analyses were conducted for low- and high-altitude sectors to determine whether a set of dynamic sector characteristics variables could reliably discriminate between operational error (OE...

Quantile Regression Methods

DEFF Research Database (Denmark)

Fitzenberger, Bernd; Wilke, Ralf Andreas

2015-01-01

if the mean regression model does not. We provide a short informal introduction into the principle of quantile regression which includes an illustrative application from empirical labor market research. This is followed by briefly sketching the underlying statistical model for linear quantile regression based......Quantile regression is emerging as a popular statistical approach, which complements the estimation of conditional mean models. While the latter only focuses on one aspect of the conditional distribution of the dependent variable, the mean, quantile regression provides more detailed insights...... by modeling conditional quantiles. Quantile regression can therefore detect whether the partial effect of a regressor on the conditional quantiles is the same for all quantiles or differs across quantiles. Quantile regression can provide evidence for a statistical relationship between two variables even...

National female literacy, individual socio-economic status, and maternal health care use in sub-Saharan Africa.

Science.gov (United States)

McTavish, Sarah; Moore, Spencer; Harper, Sam; Lynch, John

2010-12-01

The United Nations Millennium Development Goals have identified improving women's access to maternal health care as a key target in reducing maternal mortality in sub-Saharan Africa (sSA). Although individual factors such as income and urban residence can affect maternal health care use, little is known about national-level factors associated with use. Yet, such knowledge may highlight the importance of global and national policies in improving use. This study examines the importance of national female literacy on women's maternal health care use in continental sSA. Data that come from the 2002-2003 World Health Survey. Multilevel logistic regression was used to examine the association between national female literacy and individual's non-use of maternal health care, while adjusting for individual-level factors and national economic development. Analyses also assessed effect modification of the association between income and non-use by female literacy. Effect modification was evaluated with the likelihood ratio test (G(2)). We found that within countries, individual age, education, urban residence and household income were associated with lack of maternal health care. National female literacy modified the association of household income with lack of maternal health care use. The strength of the association between income and lack of maternal health care was weaker in countries with higher female literacy. We conclude therefore that higher national levels of female literacy may reduce income-related inequalities in use through a range of possible mechanisms, including women's increased labour participation and higher status in society. National policies that are able to address female literacy and women's status in sub-Saharan Africa may help reduce income-related inequalities in maternal health care use. Copyright © 2010 Elsevier Ltd. All rights reserved.

Are Competitive Materialism and Female Employment Related to International Homicide Rate?

Science.gov (United States)

Chon, Don Soo

2017-04-01

The institutional anomie theory is a proposal that states competitive materialism, an intense cultural pressure for economic success at any costs, and increased female employment may be related to a high homicide rate. The current work tested this proposition by utilizing homicide data collected from 45 developed and developing countries. Regression results did not support the proposition. Competitive materialism and female employment were not significantly related to the cross-national variation of homicide rates.

Sexually transmitted infection screening uptake and knowledge of sexually transmitted infection symptoms among female sex workers participating in a community randomised trial in Peru.

Science.gov (United States)

Kohler, Pamela K; Campos, Pablo E; Garcia, Patricia J; Carcamo, Cesar P; Buendia, Clara; Hughes, James P; Mejia, Carolina; Garnett, Geoff P; Holmes, King K

2016-04-01

This study aims to evaluate condom use, sexually transmitted infection (STI) screening, and knowledge of STI symptoms among female sex workers in Peru associated with sex work venues and a community randomised trial of STI control. One component of the Peru PREVEN intervention conducted mobile-team outreach to female sex workers to reduce STIs and increase condom use and access to government clinics for STI screening and evaluation. Prevalence ratios were calculated using multivariate Poisson regression models with robust standard errors, clustering by city. As-treated analyses were conducted to assess outcomes associated with reported exposure to the intervention. Care-seeking was more frequent in intervention communities, but differences were not statistically significant. Female sex workers reporting exposure to the intervention had a significantly higher likelihood of condom use, STI screening at public health clinics, and symptom recognition compared to those not exposed. Compared with street- or bar-based female sex workers, brothel-based female sex workers reported significantly higher rates of condom use with last client, recent screening exams for STIs, and HIV testing. Brothel-based female sex workers also more often reported knowledge of STIs and recognition of STI symptoms in women and in men. Interventions to promote STI detection and prevention among female sex workers in Peru should consider structural or regulatory factors related to sex work venues. © The Author(s) 2015.

The effect of female labour force in economic growth and sustainability in transition economies - case study for SEE countries

Directory of Open Access Journals (Sweden)

Majlinda Mazalliu

2015-07-01

Full Text Available In this research paper, the main theoretical arguments for discussions are as following: female labour force participation in transition countries, female employment in economic sectors and their main barriers, and the contributions of female labour force in economic growth. In methodology, the secondary data are used, and they are calculated through STATA program. The main analysis include: descriptive statistic, regression analysis and correlation matrix. Based on empirical results, the regression analysis has found that economic growth and government effectiveness has a negative impact on female labour force. Financial market development, enterprises reforms, and innovation have a positive impact on female labour force in SEE (South Eastern European countries. In T-statistic analysis all independent variables have shown a negative significance (T <2 on female labour force. In correlation, economic growth and financial development market have negative correlation on female labour force, but other variables have shown positive correlation. SEE countries should develop the female labour force in their economies, so their role may be crucial toward different economic problems and challenges in the modern economy.

A Monte Carlo simulation study comparing linear regression, beta regression, variable-dispersion beta regression and fractional logit regression at recovering average difference measures in a two sample design.

Science.gov (United States)

Meaney, Christopher; Moineddin, Rahim

2014-01-24

In biomedical research, response variables are often encountered which have bounded support on the open unit interval--(0,1). Traditionally, researchers have attempted to estimate covariate effects on these types of response data using linear regression. Alternative modelling strategies may include: beta regression, variable-dispersion beta regression, and fractional logit regression models. This study employs a Monte Carlo simulation design to compare the statistical properties of the linear regression model to that of the more novel beta regression, variable-dispersion beta regression, and fractional logit regression models. In the Monte Carlo experiment we assume a simple two sample design. We assume observations are realizations of independent draws from their respective probability models. The randomly simulated draws from the various probability models are chosen to emulate average proportion/percentage/rate differences of pre-specified magnitudes. Following simulation of the experimental data we estimate average proportion/percentage/rate differences. We compare the estimators in terms of bias, variance, type-1 error and power. Estimates of Monte Carlo error associated with these quantities are provided. If response data are beta distributed with constant dispersion parameters across the two samples, then all models are unbiased and have reasonable type-1 error rates and power profiles. If the response data in the two samples have different dispersion parameters, then the simple beta regression model is biased. When the sample size is small (N0 = N1 = 25) linear regression has superior type-1 error rates compared to the other models. Small sample type-1 error rates can be improved in beta regression models using bias correction/reduction methods. In the power experiments, variable-dispersion beta regression and fractional logit regression models have slightly elevated power compared to linear regression models. Similar results were observed if the

The New Strategic Imperative: Understanding the Female Business Traveler

OpenAIRE

Francine Newth

2011-01-01

This paper explores the characteristics, needs, and behaviors of women who travel on business and analyzes the data for potential segmentation. The study focuses exclusively on the female business traveler. The sample consists of 235 female business travelers from a variety of industries. The statistical methods include correlation analyses, factor analysis, and cluster analysis. The findings show that 6 factors explain 60.4% of the variance in characteristics, behaviors and needs of female b...

Association between adverse life events and addictive behaviors among male and female adolescents.

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Lee, Grace P; Storr, Carla L; Ialongo, Nicholas S; Martins, Silvia S

2012-01-01

Adverse life events have been associated with gambling and substance use as they can serve as forms of escapism. Involvement in gambling and substance use can also place individuals in adversely stressful situations. To explore potential male-female differences in the association between addictive behavior and adverse life events among an urban cohort of adolescents. The study sample comprised of 515 adolescent participants in a randomized prevention trial. With self-reported data, four addictive behavior groups were created: nonsubstance users and nongamblers, substance users only, gamblers only, and substance users and gamblers. Multinomial logistic regression analyses with interaction terms of sex and adverse life events were conducted. Adverse life events and engaging in at least one addictive behavior were common for both sexes. Substance users and gamblers had more than twice the likelihood of nonsubstance users and nongamblers to experience any event as well as events of various domains (ie, relationship, violence, and instability). Neither relationship nor instability events' associations with the co-occurrence of substance use and gambling significantly differed between sexes. Conversely, females exposed to violence events were significantly more likely than similarly exposed males to report the co-occurrence of substance use and gambling. Findings from the current study prompt future studies to devote more attention to the development of effective programs that teach adaptive coping strategies to adolescents, particularly to females upon exposure to violence. Copyright © American Academy of Addiction Psychiatry.

Representation and beyond : female victims in Post-Suharto media

NARCIS (Netherlands)

Sushartami, Wiwik

2012-01-01

This study analyses representations of female victims in post-Suharto media. In focusing on the discourse of female victimisation, it also underlines the import of the fall of the New Order regime and the opening of the media world in Indonesia at the same time. It selected notably prevalent and

A regression tree for identifying combinations of fall risk factors associated to recurrent falling: a cross-sectional elderly population-based study.

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Kabeshova, A; Annweiler, C; Fantino, B; Philip, T; Gromov, V A; Launay, C P; Beauchet, O

2014-06-01

Regression tree (RT) analyses are particularly adapted to explore the risk of recurrent falling according to various combinations of fall risk factors compared to logistic regression models. The aims of this study were (1) to determine which combinations of fall risk factors were associated with the occurrence of recurrent falls in older community-dwellers, and (2) to compare the efficacy of RT and multiple logistic regression model for the identification of recurrent falls. A total of 1,760 community-dwelling volunteers (mean age ± standard deviation, 71.0 ± 5.1 years; 49.4 % female) were recruited prospectively in this cross-sectional study. Age, gender, polypharmacy, use of psychoactive drugs, fear of falling (FOF), cognitive disorders and sad mood were recorded. In addition, the history of falls within the past year was recorded using a standardized questionnaire. Among 1,760 participants, 19.7 % (n = 346) were recurrent fallers. The RT identified 14 nodes groups and 8 end nodes with FOF as the first major split. Among participants with FOF, those who had sad mood and polypharmacy formed the end node with the greatest OR for recurrent falls (OR = 6.06 with p falls (OR = 0.25 with p factors for recurrent falls, the combination most associated with recurrent falls involving FOF, sad mood and polypharmacy. The FOF emerged as the risk factor strongly associated with recurrent falls. In addition, RT and multiple logistic regression were not sensitive enough to identify the majority of recurrent fallers but appeared efficient in detecting individuals not at risk of recurrent falls.

Regression Phalanxes

OpenAIRE

Zhang, Hongyang; Welch, William J.; Zamar, Ruben H.

2017-01-01

Tomal et al. (2015) introduced the notion of "phalanxes" in the context of rare-class detection in two-class classification problems. A phalanx is a subset of features that work well for classification tasks. In this paper, we propose a different class of phalanxes for application in regression settings. We define a "Regression Phalanx" - a subset of features that work well together for prediction. We propose a novel algorithm which automatically chooses Regression Phalanxes from high-dimensi...

Relationship between female pelvic floor dysfunction and sexual dysfunction: an observational study.

Science.gov (United States)

Bortolami, Arianna; Vanti, Carla; Banchelli, Federico; Guccione, Andrew A; Pillastrini, Paolo

2015-05-01

The ability to express one's sexuality and engage in sexual activity requires multisystemic coordination involving many psychological functions as well as the integrity of the nervous, hormonal, vascular, immune, and neuromuscular body structures and functions. The purpose of this study was to investigate the associations among pelvic floor function, sexual function, and demographic and clinical characteristics in a population of women initiating physical therapy evaluation and treatment for pelvic floor-related dysfunctions (urinary incontinence, pelvic organ prolapse, vulvodynia, vaginismus, and constipation). We consented and collected completed demographic data and data related to symptoms and clinical condition on 85 consecutive patients in an outpatient physical therapy clinic. Clinical and anthropometric characteristics were analyzed descriptively. Analysis of variance and linear regression analyses were used to analyze Female Sexual Function Index (FSFI) scale ratings, whereas zero-inflated beta-binomial regression was applied to the pain subscale. Main outcome measure was FSFI score, whereas the secondary outcome measure was the FSFI subscale score related to pain. Women in our sample were 38 years old on average, 33% of whom had given birth and 82% of whom had high tone pelvic floor. Being in the middle-tercile age group and exhibiting low pelvic floor tone (Beta = 6.8; 95% confidence interval [CI] = [1.4; 12.0]) were significantly associated with lower levels of sexual dysfunction. Women with low tone pelvic floor also reported lower pain (odds ratio = 4.0; 95% CI = [1.6; 9.6]), whereas younger aged and physically unsatisfied subjects were more likely not to have sexual activity in the month prior to scale measurement. In female patients with pelvic floor muscle dysfunction undergoing physical therapy and rehabilitation, sexual dysfunction appears to be significantly correlated with age and high pelvic floor muscle tone. © 2015

Analyses of polycyclic aromatic hydrocarbon (PAH) and chiral-PAH analogues-methyl-β-cyclodextrin guest-host inclusion complexes by fluorescence spectrophotometry and multivariate regression analysis.

Science.gov (United States)

Greene, LaVana; Elzey, Brianda; Franklin, Mariah; Fakayode, Sayo O

2017-03-05

The negative health impact of polycyclic aromatic hydrocarbons (PAHs) and differences in pharmacological activity of enantiomers of chiral molecules in humans highlights the need for analysis of PAHs and their chiral analogue molecules in humans. Herein, the first use of cyclodextrin guest-host inclusion complexation, fluorescence spectrophotometry, and chemometric approach to PAH (anthracene) and chiral-PAH analogue derivatives (1-(9-anthryl)-2,2,2-triflouroethanol (TFE)) analyses are reported. The binding constants (K b ), stoichiometry (n), and thermodynamic properties (Gibbs free energy (ΔG), enthalpy (ΔH), and entropy (ΔS)) of anthracene and enantiomers of TFE-methyl-β-cyclodextrin (Me-β-CD) guest-host complexes were also determined. Chemometric partial-least-square (PLS) regression analysis of emission spectra data of Me-β-CD-guest-host inclusion complexes was used for the determination of anthracene and TFE enantiomer concentrations in Me-β-CD-guest-host inclusion complex samples. The values of calculated K b and negative ΔG suggest the thermodynamic favorability of anthracene-Me-β-CD and enantiomeric of TFE-Me-β-CD inclusion complexation reactions. However, anthracene-Me-β-CD and enantiomer TFE-Me-β-CD inclusion complexations showed notable differences in the binding affinity behaviors and thermodynamic properties. The PLS regression analysis resulted in square-correlation-coefficients of 0.997530 or better and a low LOD of 3.81×10 -7 M for anthracene and 3.48×10 -8 M for TFE enantiomers at physiological conditions. Most importantly, PLS regression accurately determined the anthracene and TFE enantiomer concentrations with an average low error of 2.31% for anthracene, 4.44% for R-TFE and 3.60% for S-TFE. The results of the study are highly significant because of its high sensitivity and accuracy for analysis of PAH and chiral PAH analogue derivatives without the need of an expensive chiral column, enantiomeric resolution, or use of a polarized

Female Sex Offenders: Public Awareness and Attributions.

Science.gov (United States)

Cain, Calli M; Anderson, Amy L

2016-12-01

Traditional gender roles, sex scripts, and the way female sex offenders are portrayed in the media may lead to misconceptions about who can commit sexual offenses. Sexual crimes by women may go unnoticed or unreported if there is a general lack of awareness that females commit these crimes. Data from the 2012 Nebraska Annual Social Indicators Survey were used to determine whether the public perceives women as capable sex offenders and the perceived causes of female sex offending. The traditional focus on male sex offenders by researchers, media, and politicians, in addition to gender stereotypes, introduces the possibility of group differences (e.g., between men and women) in perceptions of female sex offenders. Consequently, two secondary analyses were conducted that tested for group differences in both the public's perception of whether females can commit sex offenses and the explanations selected for why females sexually offend. The findings suggest that the public does perceive women as capable sex offenders, although there were group differences in the causal attributions for female sex offending.

Effects of implementing the act of prohibition on sex trafficking on female sex workers' sexually transmitted infections.

Directory of Open Access Journals (Sweden)

Minsoo Jung

Full Text Available This study investigated the effect of implementing the act of prohibition on sex trafficking (PST on sexually transmitted disease (STD infections among South Korean female sex workers (FSWs working at prostitution blocks. Research data were collected twice through the Korean government-sanctioned survey for female sex workers (1st wave = 1,083; 2nd wave = 926. We examined the associations among health behavior, working conditions, and the effect of PST act via hierarchical logistic regression analyses using propensity score matching. After adjusted covariates, the risk probability was 0.288 times lower among FSWs who had remained in prostitute blocks after the PST act enforcement compared to FSWs who had worked before the PST. Similarly, the risk probability for a gonorrhea infection was 0.219 times lower among FSWs who had remained in prostitute blocks after the PST act compared to FSWs who had worked before the PST. Therefore, this study showed that, besides already known factors, the implementation and establishment of the PST Act was a strong factor that suppressed STD infections among FSWs.

The male-female earnings gap for nurses in Germany: A pooled cross-sectional study of the years 2006 and 2012.

Science.gov (United States)

Muench, Ulrike; Dietrich, Hans

2017-07-14

Nursing is one of the largest occupations for women in every country. Evidence suggests a substantial male-female pay gap for registered nurses in the U.S., possibly contributing to disparities between genders more broadly. Differences in motivation and skills between men and women have long been considered important factors in the gender earnings gap, but these factors are difficult to measure. Because of country specific educational pathways and limited upward job mobility in Germany, nurses tend to be more homogenous in their motivation to work and their work skills compared to the U.S. To study male-female earnings in the nursing labor market in Germany. This is a pooled cross-sectional study of survey data collected for the years 2006 and 2012. We used a representative survey of nurses (n=828) who are active labor force participants. In a multivariate ordinary least squares regression, the analysis estimated the log of monthly earnings for male and female nurses. The full model accounted for demographic, human capital, and geographic characteristics, in addition to employment characteristics, such as hours worked, additional education obtained, years of nursing experience, years of labor market experience, career inactivity, years with the employer, and responsibilities at work, among other factors. We conducted follow-up analyses to test alternative explanations for the pay gap, examining earnings for nurses who no longer worked in nursing and testing potential differences in motivation with the likelihood of working nightshifts and length of time with current employer. Unadjusted monthly earnings for full-time male nurses were 30% higher, or 700 Euros more, than monthly earnings for full-time female nurses. In the fully adjusted analysis, male nurses out-earned female nurses by approximately 9.3%, or 260 Euros per month. Follow-up analyses suggested that better outside options exist for male than female nurses in the German labor market, while we found no

A method for fitting regression splines with varying polynomial order in the linear mixed model.

Science.gov (United States)

Edwards, Lloyd J; Stewart, Paul W; MacDougall, James E; Helms, Ronald W

2006-02-15

The linear mixed model has become a widely used tool for longitudinal analysis of continuous variables. The use of regression splines in these models offers the analyst additional flexibility in the formulation of descriptive analyses, exploratory analyses and hypothesis-driven confirmatory analyses. We propose a method for fitting piecewise polynomial regression splines with varying polynomial order in the fixed effects and/or random effects of the linear mixed model. The polynomial segments are explicitly constrained by side conditions for continuity and some smoothness at the points where they join. By using a reparameterization of this explicitly constrained linear mixed model, an implicitly constrained linear mixed model is constructed that simplifies implementation of fixed-knot regression splines. The proposed approach is relatively simple, handles splines in one variable or multiple variables, and can be easily programmed using existing commercial software such as SAS or S-plus. The method is illustrated using two examples: an analysis of longitudinal viral load data from a study of subjects with acute HIV-1 infection and an analysis of 24-hour ambulatory blood pressure profiles.

The study of logistic regression of risk factor on the death cause of uranium miners

International Nuclear Information System (INIS)

Wen Jinai; Yuan Liyun; Jiang Ruyi

1999-01-01

Logistic regression model has widely been used in the field of medicine. The computer software on this model is popular, but it is worth to discuss how to use this model correctly. Using SPSS (Statistical Package for the Social Science) software, unconditional logistic regression method was adopted to carry out multi-factor analyses on the cause of total death, cancer death and lung cancer death of uranium miners. The data is from radioepidemiological database of one uranium mine. The result show that attained age is a risk factor in the logistic regression analyses of total death, cancer death and lung cancer death. In the logistic regression analysis of cancer death, there is a negative correlation between the age of exposure and cancer death. This shows that the younger the age at exposure, the bigger the risk of cancer death. In the logistic regression analysis of lung cancer death, there is a positive correlation between the cumulated exposure and lung cancer death, this show that cumulated exposure is a most important risk factor of lung cancer death on uranium miners. It has been documented by many foreign reports that the lung cancer death rate is higher in uranium miners

Depression in Female Veterans Returning from Deployment: The Role of Social Factors.

Science.gov (United States)

Sairsingh, Holly; Solomon, Phyllis; Helstrom, Amy; Treglia, Dan

2018-03-01

Women are serving in the armed forces and deployed to areas of conflict in increasing numbers. Problems such as depressive symptoms and risks related to combat exposure can have negative effects on adjustment following service; understanding the relationship between these problems may contribute to strategies providers can use to facilitate healthy adjustment after deployment. The purpose of this study is to examine social factors as they relate to mental health adjustment, namely depressive symptoms among female veterans who served in Iraq and Afghanistan as part of Operation Enduring Freedom, Operation Iraqi Freedom, and Operation New Dawn (OND). We hypothesized that combat exposure would predict higher levels of depressive symptoms and that social support would moderate the relationship between combat exposure and depression. In a cross-sectional design, 128 female Operation Enduring Freedom/Operation Iraqi Freedom/Operation New Dawn veterans completed an online survey about combat experience, social support, depression, demographic characteristics, and behavioral health symptom history. We conducted multiple regression analyses to examine linear and moderating relationships. There was no significant relationship between combat exposure and depression; social support did not significantly moderate the relationship between combat exposure and depression. However, higher levels of social support and financial comfort were significantly related to lower levels of depression. This study highlights the role of social factors, specifically social support and perceived financial status, as potential barriers to healthy emotional readjustment following deployment. These findings suggest that it may be beneficial for mental health providers to screen female veterans and refer them to appropriate services to reduce financial stressors and strengthen their use of social support. More research should continue to examine more fully the impact of combat exposure on female

Prevalence and correlates of contraceptive use among female adolescents in Ghana.

Science.gov (United States)

Nyarko, Samuel H

2015-08-19

Adolescence is a critical stage in the life course and evidence suggests that even though contraceptive use has been steadily increasing among women in Ghana over the past years, contraceptive prevalence and determinants among female adolescents is quite lacking. This paper examines the prevalence and correlates of contraceptive use among female adolescents in Ghana. The paper used data from the 2008 Ghana Demographic and Health survey. Bivariate analysis was carried out to determine the contraceptive prevalence among female adolescents while logistic regression analysis was applied to examine the correlates of female adolescent contraceptive use. The study founded that female adolescent contraceptive use was significantly determined by age of adolescent, education, work status, knowledge of ovulatory cycle, visit of health facility and marital status. This has implications for adolescent sexual and reproductive health programmes in Ghana. It is therefore essential to intensify girl child education and strengthen the provision of family planning information and services for female adolescents in the country.

The relationship of gender balance at work, family responsibilities and workplace characteristics to drinking among male and female attorneys.

Science.gov (United States)

Shore, E R

1997-05-01

The purpose of this study was to investigate the relationship of gender balance at work, family and home responsibilities and workplace factors to the drinking behaviors of attorneys. Using a stratified random sampling procedure, attorneys were selected from the bar associations of two large Midwestern cities. Telephone interviews were completed with 300 men and 257 women (37.3% of those originally selected), who were asked about characteristics of their work, the numbers of female attorneys they had contact with in four types of working relationships, overall and work-related drinking, and family and home responsibilities. Multiple regression and discriminant analyses were used to study the influence of these variables on drinking. Gender balance variables entered several of the analyses. For both men and women the frequency of work-related drinking positively correlated with the number of female attorneys in the organization, but was negatively related to the number of women who were peers. Family and home responsibilities entered predictive equations, both positively and negatively, for both men and women. Size of firm was positively correlated with frequency of business-related drinking and, for men, with frequency of social drinking related to work. The influence of the gender composition of the workplace on drinking behaviors may vary, for both men and women, by the type of contact involved, with closer or more active involvement with female colleagues associated with decreased frequency of drinking. Work-related drinking may also be related to home and family demands and the size of the firm, again for both genders.

Advanced statistics: linear regression, part II: multiple linear regression.

Science.gov (United States)

Marill, Keith A

2004-01-01

The applications of simple linear regression in medical research are limited, because in most situations, there are multiple relevant predictor variables. Univariate statistical techniques such as simple linear regression use a single predictor variable, and they often may be mathematically correct but clinically misleading. Multiple linear regression is a mathematical technique used to model the relationship between multiple independent predictor variables and a single dependent outcome variable. It is used in medical research to model observational data, as well as in diagnostic and therapeutic studies in which the outcome is dependent on more than one factor. Although the technique generally is limited to data that can be expressed with a linear function, it benefits from a well-developed mathematical framework that yields unique solutions and exact confidence intervals for regression coefficients. Building on Part I of this series, this article acquaints the reader with some of the important concepts in multiple regression analysis. These include multicollinearity, interaction effects, and an expansion of the discussion of inference testing, leverage, and variable transformations to multivariate models. Examples from the first article in this series are expanded on using a primarily graphic, rather than mathematical, approach. The importance of the relationships among the predictor variables and the dependence of the multivariate model coefficients on the choice of these variables are stressed. Finally, concepts in regression model building are discussed.

A cost of sexual attractiveness to high-fitness females.

Directory of Open Access Journals (Sweden)

Tristan A F Long

2009-12-01

Full Text Available Adaptive mate choice by females is an important component of sexual selection in many species. The evolutionary consequences of male mate preferences, however, have received relatively little study, especially in the context of sexual conflict, where males often harm their mates. Here, we describe a new and counterintuitive cost of sexual selection in species with both male mate preference and sexual conflict via antagonistic male persistence: male mate choice for high-fecundity females leads to a diminished rate of adaptive evolution by reducing the advantage to females of expressing beneficial genetic variation. We then use a Drosophila melanogaster model system to experimentally test the key prediction of this theoretical cost: that antagonistic male persistence is directed toward, and harms, intrinsically higher-fitness females more than it does intrinsically lower-fitness females. This asymmetry in male persistence causes the tails of the population's fitness distribution to regress towards the mean, thereby reducing the efficacy of natural selection. We conclude that adaptive male mate choice can lead to an important, yet unappreciated, cost of sex and sexual selection.

Boosted beta regression.

Directory of Open Access Journals (Sweden)

Matthias Schmid

Full Text Available Regression analysis with a bounded outcome is a common problem in applied statistics. Typical examples include regression models for percentage outcomes and the analysis of ratings that are measured on a bounded scale. In this paper, we consider beta regression, which is a generalization of logit models to situations where the response is continuous on the interval (0,1. Consequently, beta regression is a convenient tool for analyzing percentage responses. The classical approach to fit a beta regression model is to use maximum likelihood estimation with subsequent AIC-based variable selection. As an alternative to this established - yet unstable - approach, we propose a new estimation technique called boosted beta regression. With boosted beta regression estimation and variable selection can be carried out simultaneously in a highly efficient way. Additionally, both the mean and the variance of a percentage response can be modeled using flexible nonlinear covariate effects. As a consequence, the new method accounts for common problems such as overdispersion and non-binomial variance structures.

Gender roles and binge drinking among Latino emerging adults: a latent class regression analysis.

Science.gov (United States)

Vaughan, Ellen L; Wong, Y Joel; Middendorf, Katharine G

2014-09-01

Gender roles are often cited as a culturally specific predictor of drinking among Latino populations. This study used latent class regression to test the relationships between gender roles and binge drinking in a sample of Latino emerging adults. Participants were Latino emerging adults who participated in Wave III of the National Longitudinal Study of Adolescent Health (N = 2,442). A subsample of these participants (n = 660) completed the Bem Sex Role Inventory--Short. We conducted latent class regression using 3 dimensions of gender roles (femininity, social masculinity, and personal masculinity) to predict binge drinking. Results indicated a 3-class solution. In Class 1, the protective personal masculinity class, personal masculinity (e.g., being a leader, defending one's own beliefs) was associated with a reduction in the odds of binge drinking. In Class 2, the nonsignificant class, gender roles were not related to binge drinking. In Class 3, the mixed masculinity class, personal masculinity was associated with a reduction in the odds of binge drinking, whereas social masculinity (e.g., forceful, dominant) was associated with an increase in the odds of binge drinking. Post hoc analyses found that females, those born outside the United States, and those with greater English language usage were at greater odds of being in Class 1 (vs. Class 2). Males, those born outside the United States, and those with greater Spanish language usage were at greater odds of being in Class 3 (vs. Class 2). Directions for future research and implications for practice with Latino emerging adults are discussed.

Male and female child murderers: an empirical analysis of U.S. arrest data.

Science.gov (United States)

Sellers, Brian G; Heide, Kathleen M

2012-08-01

Recent U.S. cases of murders by children below age 11 have captured national headlines. A review of the literature reveals that little is known about this population of juvenile homicide offenders (JHOs). Most studies on juvenile murderers have used small clinical samples, focused on adolescents, and concentrated on male offenders. Studies that have used Supplementary Homicide Report (SHR) data have found significant gender differences among juveniles below 18 years arrested for murder. This study investigated gender differences among 226 juvenile murderers ages 6 through 10 involved in single-victim incidents using bivariate and multivariate statistical techniques. Consistent with previous research, bivariate analyses revealed gender differences with respect to the type of weapon used, age of the victim, relationship to the victim, and circumstances of the crime. Logistic regression analysis identified female JHOs as more likely to use a knife, kill a family member, and kill a victim below age 5, when compared with male JHOs. From these findings, profiles of young male and female JHOs can be drawn. The article concludes with a discussion of the study's implications for prevention and treatment. The authors recommend that future research in gender differences among young children focus on examining psychological, neurological, and sociological variables not included in the SHR data set.

Regression to Causality : Regression-style presentation influences causal attribution

DEFF Research Database (Denmark)

Bordacconi, Mats Joe; Larsen, Martin Vinæs

2014-01-01

of equivalent results presented as either regression models or as a test of two sample means. Our experiment shows that the subjects who were presented with results as estimates from a regression model were more inclined to interpret these results causally. Our experiment implies that scholars using regression...... models – one of the primary vehicles for analyzing statistical results in political science – encourage causal interpretation. Specifically, we demonstrate that presenting observational results in a regression model, rather than as a simple comparison of means, makes causal interpretation of the results...... more likely. Our experiment drew on a sample of 235 university students from three different social science degree programs (political science, sociology and economics), all of whom had received substantial training in statistics. The subjects were asked to compare and evaluate the validity...

Migrant female head porters' enrolment in and utilisation and renewal of the National Health Insurance Scheme in Kumasi, Ghana.

Science.gov (United States)

Boateng, Simon; Amoako, Prince; Poku, Adjoa Afriyie; Baabereyir, Anthony; Gyasi, Razak Mohammed

2017-01-01

As a social protection policy, Ghana's National Health Insurance Scheme (NHIS) aims to improve access to healthcare, especially for the vulnerable. Migrant female head porters ( kayayoo ), who are part of the informal economic workforce, are underscored as an ethnic minority and vulnerable group in Ghana. This study aimed to analyse the factors associated with enrolment in and renewal and utilisation of the NHIS among migrant female head porters in the Kumasi Metropolis. We purposively sampled 392 migrant female head porters in the Kejetia, Asafo and Bantama markets. We used a binary logit regression model to estimate associations among baseline characteristics, convenience and benefit factors and enrolment in and renewal and utilisation of the NHIS. Age and income significantly increased the probability of NHIS enrolment, renewal and utilisation. Long waiting times at NHIS offices significantly reduced the likelihood of renewal, while provision of drugs highly significantly increased the tendency for migrant female head porters to enrol in, renew and use the NHIS. Consulting and surgery also significantly increased renewal and utilisation of the NHIS. Political commitment is imperative for effective implementation of the decentralisation policy of the NHIS through the National Health Insurance Authority in Kumasi. We argue that retail offices should be well equipped with logistic facilities to ensure convenience in NHIS initial enrolment and renewal processes by citizenry, and by vulnerable groups in particular.

Correcting for multivariate measurement error by regression calibration in meta-analyses of epidemiological studies

DEFF Research Database (Denmark)

Tybjærg-Hansen, Anne

2009-01-01

Within-person variability in measured values of multiple risk factors can bias their associations with disease. The multivariate regression calibration (RC) approach can correct for such measurement error and has been applied to studies in which true values or independent repeat measurements...... of the risk factors are observed on a subsample. We extend the multivariate RC techniques to a meta-analysis framework where multiple studies provide independent repeat measurements and information on disease outcome. We consider the cases where some or all studies have repeat measurements, and compare study......-specific, averaged and empirical Bayes estimates of RC parameters. Additionally, we allow for binary covariates (e.g. smoking status) and for uncertainty and time trends in the measurement error corrections. Our methods are illustrated using a subset of individual participant data from prospective long-term studies...

THE IMPACT OF FEMALE DIRECTORS ON FIRM PERFORMANCE: EVIDENCE FROM INDONESIA

OpenAIRE

Triana; Marwan Asri

2017-01-01

This research shows the impact of female directors on firm performance in Indonesia by using as its sample the public companies listed on the Indonesian Stock Exchange (IDX) from 2011 until 2015. There were 347 companies, with 1,735 samples observed. This research uses the multiple regression method. The model is a modified model from 9 recent articles published between 2012 and 2015. The empirical result shows that a female director has a positive significant effect on firm performance. The ...

Factors related to burnout among Chinese female hospital nurses: cross-sectional survey in Liaoning Province of China.

Science.gov (United States)

Wu, Hui; Liu, Li; Sun, Wei; Zhao, Xue; Wang, Jiana; Wang, Lie

2014-07-01

To explore the factors associated with burnout among female hospital nurses in China. Burnout has been a major concern in the field of occupational health, and yet there has been little research exploring the factors related to burnout among Chinese nurses. Exploring the factors associated with burnout is important in improving nurses' health and the quality of health care services in China. The study population consisted of 1845 female hospital nurses in the Liaoning Province of China. Burnout was measured using the Chinese version of the Maslach Burnout Inventory-General Survey; occupational stress was measured using the Chinese versions of the Job Content Questionnaire and Effort-Reward Imbalance Questionnaire. A general linear regression model was applied to analyse the factors associated with burnout. Mean scores (±SD) were 11.74 (7.14) for emotional exhaustion, 7.12 (5.67) for cynicism and 23.34 (9.60) for self-efficacy. Strong extrinsic effort was the most powerful predictor of emotional exhaustion and cynicism; strong psychological job demands were the most robust predictor of low self-efficacy. The findings suggest that occupational stress was strongly related to burnout among female hospital nurses in China. Occupational stress was identified as the most robust predictor of burnout among Chinese female hospital nurses. Reducing burnout among nurses working in China may require health education, health promotion and occupational training programmes aimed at improving work situations and reducing occupational stress. © 2012 John Wiley & Sons Ltd.

Psychiatric and addictive symptoms of young adult female indoor tanners.

Science.gov (United States)

Heckman, Carolyn J; Cohen-Filipic, Jessye; Darlow, Susan; Kloss, Jacqueline D; Manne, Sharon L; Munshi, Teja

2014-01-01

Indoor tanning (IT) increases risk for melanoma and is particularly common among young adult women. IT has also been linked with some psychiatric symptoms, and frequent tanning may indicate tanning dependence (addiction) associated with endorphin release during ultraviolet radiation exposure. The objective of the current study was to investigate associations between IT, tanning dependence, and psychiatric and substance use symptoms in young adult women. Cross-sectional survey and psychiatric interview. Online, except for the Mini International Neuropsychiatric Interview (MINI), which was completed over the telephone. Participants were 306 female university students aged 18 to 25 years. MINI, Seasonal Scale Index, tanning dependence scales, reporting ever having used a tanning bed or booth with tanning lamps (single item), reporting smoking a cigarette in the last 30 days (single item). Descriptive statistics, χ(2) analysis, multivariate logistic regression. Forty-six percent of the sample reported a history of IT, and 25% were classified as tanning dependent. Multivariate logistic regression analyses showed that IT was significantly associated with symptoms of alcohol use disorders, generalized anxiety, and not having social anxiety. Tanning dependence was associated with symptoms of alcohol use disorders. Tanning is of concern not only for its association with skin cancer but for its association with psychiatric and substance use symptoms. Young women with certain psychological problems may seek relief from their symptoms by IT. These findings suggest that indoor tanners may benefit from health behavior and other psychosocial interventions.

Multiplication factor versus regression analysis in stature estimation from hand and foot dimensions.

Science.gov (United States)

Krishan, Kewal; Kanchan, Tanuj; Sharma, Abhilasha

2012-05-01

Estimation of stature is an important parameter in identification of human remains in forensic examinations. The present study is aimed to compare the reliability and accuracy of stature estimation and to demonstrate the variability in estimated stature and actual stature using multiplication factor and regression analysis methods. The study is based on a sample of 246 subjects (123 males and 123 females) from North India aged between 17 and 20 years. Four anthropometric measurements; hand length, hand breadth, foot length and foot breadth taken on the left side in each subject were included in the study. Stature was measured using standard anthropometric techniques. Multiplication factors were calculated and linear regression models were derived for estimation of stature from hand and foot dimensions. Derived multiplication factors and regression formula were applied to the hand and foot measurements in the study sample. The estimated stature from the multiplication factors and regression analysis was compared with the actual stature to find the error in estimated stature. The results indicate that the range of error in estimation of stature from regression analysis method is less than that of multiplication factor method thus, confirming that the regression analysis method is better than multiplication factor analysis in stature estimation. Copyright © 2012 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

Engineering Women’s Attitudes and Goals in Choosing Disciplines with above and Below Average Female Representation

OpenAIRE

Dina Verdín; Allison Godwin; Adam Kirn; Lisa Benson; Geoff Potvin

2018-01-01

Women’s participation in engineering remains well below that of men at all degree levels. However, despite the low enrollment of women in engineering as a whole, some engineering disciplines report above average female enrollment. We used multiple linear regression to examine the attitudes, beliefs, career outcome expectations, and career choice of first-year female engineering students enrolled in below average, average, and above average female representation disciplines in engineering. Our...

Information fusion via constrained principal component regression for robust quantification with incomplete calibrations

International Nuclear Information System (INIS)

Vogt, Frank

2013-01-01

Graphical abstract: Analysis Task: Determine the albumin (= protein) concentration in microalgae cells as a function of the cells’ nutrient availability. Left Panel: The predicted albumin concentrations as obtained by conventional principal component regression features low reproducibility and are partially higher than the concentrations of algae in which albumin is contained. Right Panel: Augmenting an incomplete PCR calibration with additional expert information derives reasonable albumin concentrations which now reveal a significant dependency on the algae's nutrient situation. -- Highlights: •Make quantitative analyses of compounds embedded in largely unknown chemical matrices robust. •Improved concentration prediction with originally insufficient calibration models. •Chemometric approach for incorporating expertise from other fields and/or researchers. •Ensure chemical, biological, or medicinal meaningfulness of quantitative analyses. -- Abstract: Incomplete calibrations are encountered in many applications and hamper chemometric data analyses. Such situations arise when target analytes are embedded in a chemically complex matrix from which calibration concentrations cannot be determined with reasonable efforts. In other cases, the samples’ chemical composition may fluctuate in an unpredictable way and thus cannot be comprehensively covered by calibration samples. The reason for calibration model to fail is the regression principle itself which seeks to explain measured data optimally in terms of the (potentially incomplete) calibration model but does not consider chemical meaningfulness. This study presents a novel chemometric approach which is based on experimentally feasible calibrations, i.e. concentration series of the target analytes outside the chemical matrix (‘ex situ calibration’). The inherent lack-of-information is then compensated by incorporating additional knowledge in form of regression constraints. Any outside knowledge can be

Paradox of spontaneous cancer regression: implications for fluctuational radiothermy and radiotherapy

International Nuclear Information System (INIS)

Roy, Prasun K.; Dutta Majumder, D.; Biswas, Jaydip

1999-01-01

Spontaneous regression of malignant tumours without treatment is a most enigmatic phenomenon with immense therapeutic potentialities. We analyse such cases to find that the commonest cause is a preceding episode of high fever-induced thermal fluctuation which produce fluctuation of biochemical and immunological parameters. Using Prigogine-Glansdorff thermodynamic stability formalism and biocybernetic principles, we develop the theoretical foundation of tumour regression induced by thermal, radiational or oxygenational fluctuations. For regression, a preliminary threshold condition of fluctuations is derived, namely σ > 2.83. We present some striking confirmation of such fluctuation-induced regression of various therapy-resistant masses as Ewing tumour, neurogranuloma and Lewis lung carcinoma by utilising σ > 2.83. Our biothermodynamic stability model of malignancy appears to illuminate the marked increase of aggressiveness of mammalian malignancy which occurred around 250 million years ago when homeothermic warm-blooded pre-mammals evolved. Using experimental data, we propose a novel approach of multi-modal hyper-fluctuation therapy involving modulation of radiotherapeutic hyper-fractionation, temperature, radiothermy and immune-status. (author)

Spontaneous regression of intracranial malignant lymphoma. Case report

Energy Technology Data Exchange (ETDEWEB)

Kojo, Nobuto; Tokutomi, Takashi; Eguchi, Gihachirou; Takagi, Shigeyuki; Matsumoto, Tomie; Sasaguri, Yasuyuki; Shigemori, Minoru.

1988-05-01

In a 46-year-old female with a 1-month history of gait and speech disturbances, computed tomography (CT) demonstrated mass lesions of slightly high density in the left basal ganglia and left frontal lobe. The lesions were markedly enhanced by contrast medium. The patient received no specific treatment, but her clinical manifestations gradually abated and the lesions decreased in size. Five months after her initial examination, the lesions were absent on CT scans; only a small area of low density remained. Residual clinical symptoms included mild right hemiparesis and aphasia. After 14 months the patient again deteriorated, and a CT scan revealed mass lesions in the right frontal lobe and the pons. However, no enhancement was observed in the previously affected regions. A biopsy revealed malignant lymphoma. Despite treatment with steroids and radiation, the patient's clinical status progressively worsened and she died 27 months after initial presentation. Seven other cases of spontaneous regression of primary malignant lymphoma have been reported. In this case, the mechanism of the spontaneous regression was not clear, but changes in immunologic status may have been involved.

Quantile regression analysis of body mass and wages.

Science.gov (United States)

Johar, Meliyanni; Katayama, Hajime

2012-05-01

Using the National Longitudinal Survey of Youth 1979, we explore the relationship between body mass and wages. We use quantile regression to provide a broad description of the relationship across the wage distribution. We also allow the relationship to vary by the degree of social skills involved in different jobs. Our results find that for female workers body mass and wages are negatively correlated at all points in their wage distribution. The strength of the relationship is larger at higher-wage levels. For male workers, the relationship is relatively constant across wage distribution but heterogeneous across ethnic groups. When controlling for the endogeneity of body mass, we find that additional body mass has a negative causal impact on the wages of white females earning more than the median wages and of white males around the median wages. Among these workers, the wage penalties are larger for those employed in jobs that require extensive social skills. These findings may suggest that labor markets reward white workers for good physical shape differently, depending on the level of wages and the type of job a worker has. Copyright © 2011 John Wiley & Sons, Ltd.

Gender effects in gaming research: a case for regression residuals?

Science.gov (United States)

Pfister, Roland

2011-10-01

Numerous recent studies have examined the impact of video gaming on various dependent variables, including the players' affective reactions, positive as well as detrimental cognitive effects, and real-world aggression. These target variables are typically analyzed as a function of game characteristics and player attributes-especially gender. However, findings on the uneven distribution of gaming experience between males and females, on the one hand, and the effect of gaming experience on several target variables, on the other hand, point at a possible confound when gaming experiments are analyzed with a standard analysis of variance. This study uses simulated data to exemplify analysis of regression residuals as a potentially beneficial data analysis strategy for such datasets. As the actual impact of gaming experience on each of the various dependent variables differs, the ultimate benefits of analysis of regression residuals entirely depend on the research question, but it offers a powerful statistical approach to video game research whenever gaming experience is a confounding factor.

Global Prevalence of Elder Abuse: A Meta-analysis and Meta-regression.

Science.gov (United States)

Ho, C Sh; Wong, S Y; Chiu, M M; Ho, R Cm

2017-06-01

Elder abuse is increasingly recognised as a global public health and social problem. There has been limited inter-study comparison of the prevalence and risk factors for elder abuse. This study aimed to estimate the pooled and subtype prevalence of elder abuse worldwide and identify significant associated risk factors. We conducted a meta-analysis and meta-regression of 34 population-based and 17 non-population-based studies. The pooled prevalences of elder abuse were 10.0% (95% confidence interval, 5.2%-18.6%) and 34.3% (95% confidence interval, 22.9%-47.8%) in population-based studies and third party- or caregiver-reported studies, respectively. Being in a marital relationship was found to be a significant moderator using random-effects model. This meta-analysis revealed that third parties or caregivers were more likely to report abuse than older abused adults. Subgroup analyses showed that females and those resident in non-western countries were more likely to be abused. Emotional abuse was the most prevalent elder abuse subtype and financial abuse was less commonly reported by third parties or caregivers. Heterogeneity in the prevalence was due to the high proportion of married older adults in the sample. Subgroup analysis showed that cultural factors, subtypes of abuse, and gender also contributed to heterogeneity in the pooled prevalence of elder abuse.

Physics constrained nonlinear regression models for time series

International Nuclear Information System (INIS)

Majda, Andrew J; Harlim, John

2013-01-01

A central issue in contemporary science is the development of data driven statistical nonlinear dynamical models for time series of partial observations of nature or a complex physical model. It has been established recently that ad hoc quadratic multi-level regression (MLR) models can have finite-time blow up of statistical solutions and/or pathological behaviour of their invariant measure. Here a new class of physics constrained multi-level quadratic regression models are introduced, analysed and applied to build reduced stochastic models from data of nonlinear systems. These models have the advantages of incorporating memory effects in time as well as the nonlinear noise from energy conserving nonlinear interactions. The mathematical guidelines for the performance and behaviour of these physics constrained MLR models as well as filtering algorithms for their implementation are developed here. Data driven applications of these new multi-level nonlinear regression models are developed for test models involving a nonlinear oscillator with memory effects and the difficult test case of the truncated Burgers–Hopf model. These new physics constrained quadratic MLR models are proposed here as process models for Bayesian estimation through Markov chain Monte Carlo algorithms of low frequency behaviour in complex physical data. (paper)

Temporal Synchronization Analysis for Improving Regression Modeling of Fecal Indicator Bacteria Levels

Science.gov (United States)

Multiple linear regression models are often used to predict levels of fecal indicator bacteria (FIB) in recreational swimming waters based on independent variables (IVs) such as meteorologic, hydrodynamic, and water-quality measures. The IVs used for these analyses are traditiona...

Regressão múltipla stepwise e hierárquica em Psicologia Organizacional: aplicações, problemas e soluções Stepwise and hierarchical multiple regression in organizational psychology: Applications, problemas and solutions

Directory of Open Access Journals (Sweden)

Gardênia Abbad

2002-01-01

Full Text Available Este artigo discute algumas aplicações das técnicas de análise de regressão múltipla stepwise e hierárquica, as quais são muito utilizadas em pesquisas da área de Psicologia Organizacional. São discutidas algumas estratégias de identificação e de solução de problemas relativos à ocorrência de erros do Tipo I e II e aos fenômenos de supressão, complementaridade e redundância nas equações de regressão múltipla. São apresentados alguns exemplos de pesquisas nas quais esses padrões de associação entre variáveis estiveram presentes e descritas as estratégias utilizadas pelos pesquisadores para interpretá-los. São discutidas as aplicações dessas análises no estudo de interação entre variáveis e na realização de testes para avaliação da linearidade do relacionamento entre variáveis. Finalmente, são apresentadas sugestões para lidar com as limitações das análises de regressão múltipla (stepwise e hierárquica.This article discusses applications of stepwise and hierarchical multiple regression analyses to research in organizational psychology. Strategies for identifying type I and II errors, and solutions to potential problems that may arise from such errors are proposed. In addition, phenomena such as suppression, complementarity, and redundancy are reviewed. The article presents examples of research where these phenomena occurred, and the manner in which they were explained by researchers. Some applications of multiple regression analyses to studies involving between-variable interactions are presented, along with tests used to analyze the presence of linearity among variables. Finally, some suggestions are provided for dealing with limitations implicit in multiple regression analyses (stepwise and hierarchical.

Pregnant women carrying female fetuses are at higher risk of placental malaria infection.

Directory of Open Access Journals (Sweden)

Ishag Adam

Full Text Available The pathophysiology of the placental malaria is not fully understood. If there is a fetal sex-specific susceptibility to malaria infection, this might add to the previous knowledge on the immunology, endocrinology and pathophysiology of placental malaria infections.This study was conducted to assess whether the sex of the fetus was associated with placental malaria infections.A cross-sectional study was performed including a secondary analysis of a cohort of women who were investigated for prevalence and risk factors (including fetal sex for placental malaria in eastern Sudan. Placental histology was used to diagnose placental malaria infections.Among 339 women enrolled, the mean (SD age was 25.8 (6.7 years and parity was 2.7 (2.2. Among the new born babies, 157 (46.3% were male and 182 (53.7% were female. Five (1.5%, 9 (2.7% and 103 (30.4% of the 339 placentas had active, active-chronic, past-chronic malaria infection on histopathology examination respectively, while 222 (65.5% of them showed no malaria infection. Logistic regression analyses showed no associations between maternal age or parity and placental malaria infections. Women who have blood group O (OR = 1.95, 95% CI = 1.19-3.10; P = 0.007 and women who had female new born were at higher risk for placental malaria infections (OR = 2.55, 95% CI = 1.57-4.13; P< 0.001.Fetal gender may be a novel risk factor for placental malaria. In this work the female placentas were at higher risk for malaria infections than the male placentas.

Use of probabilistic weights to enhance linear regression myoelectric control

Science.gov (United States)

Smith, Lauren H.; Kuiken, Todd A.; Hargrove, Levi J.

2015-12-01

Objective. Clinically available prostheses for transradial amputees do not allow simultaneous myoelectric control of degrees of freedom (DOFs). Linear regression methods can provide simultaneous myoelectric control, but frequently also result in difficulty with isolating individual DOFs when desired. This study evaluated the potential of using probabilistic estimates of categories of gross prosthesis movement, which are commonly used in classification-based myoelectric control, to enhance linear regression myoelectric control. Approach. Gaussian models were fit to electromyogram (EMG) feature distributions for three movement classes at each DOF (no movement, or movement in either direction) and used to weight the output of linear regression models by the probability that the user intended the movement. Eight able-bodied and two transradial amputee subjects worked in a virtual Fitts’ law task to evaluate differences in controllability between linear regression and probability-weighted regression for an intramuscular EMG-based three-DOF wrist and hand system. Main results. Real-time and offline analyses in able-bodied subjects demonstrated that probability weighting improved performance during single-DOF tasks (p < 0.05) by preventing extraneous movement at additional DOFs. Similar results were seen in experiments with two transradial amputees. Though goodness-of-fit evaluations suggested that the EMG feature distributions showed some deviations from the Gaussian, equal-covariance assumptions used in this experiment, the assumptions were sufficiently met to provide improved performance compared to linear regression control. Significance. Use of probability weights can improve the ability to isolate individual during linear regression myoelectric control, while maintaining the ability to simultaneously control multiple DOFs.

Evaluation of Linear Regression Simultaneous Myoelectric Control Using Intramuscular EMG.

Science.gov (United States)

Smith, Lauren H; Kuiken, Todd A; Hargrove, Levi J

2016-04-01

The objective of this study was to evaluate the ability of linear regression models to decode patterns of muscle coactivation from intramuscular electromyogram (EMG) and provide simultaneous myoelectric control of a virtual 3-DOF wrist/hand system. Performance was compared to the simultaneous control of conventional myoelectric prosthesis methods using intramuscular EMG (parallel dual-site control)-an approach that requires users to independently modulate individual muscles in the residual limb, which can be challenging for amputees. Linear regression control was evaluated in eight able-bodied subjects during a virtual Fitts' law task and was compared to performance of eight subjects using parallel dual-site control. An offline analysis also evaluated how different types of training data affected prediction accuracy of linear regression control. The two control systems demonstrated similar overall performance; however, the linear regression method demonstrated improved performance for targets requiring use of all three DOFs, whereas parallel dual-site control demonstrated improved performance for targets that required use of only one DOF. Subjects using linear regression control could more easily activate multiple DOFs simultaneously, but often experienced unintended movements when trying to isolate individual DOFs. Offline analyses also suggested that the method used to train linear regression systems may influence controllability. Linear regression myoelectric control using intramuscular EMG provided an alternative to parallel dual-site control for 3-DOF simultaneous control at the wrist and hand. The two methods demonstrated different strengths in controllability, highlighting the tradeoff between providing simultaneous control and the ability to isolate individual DOFs when desired.

Using synthetic data to evaluate multiple regression and principal component analyses for statistical modeling of daily building energy consumption

Energy Technology Data Exchange (ETDEWEB)

Reddy, T.A. (Energy Systems Lab., Texas A and M Univ., College Station, TX (United States)); Claridge, D.E. (Energy Systems Lab., Texas A and M Univ., College Station, TX (United States))

1994-01-01

Multiple regression modeling of monitored building energy use data is often faulted as a reliable means of predicting energy use on the grounds that multicollinearity between the regressor variables can lead both to improper interpretation of the relative importance of the various physical regressor parameters and to a model with unstable regressor coefficients. Principal component analysis (PCA) has the potential to overcome such drawbacks. While a few case studies have already attempted to apply this technique to building energy data, the objectives of this study were to make a broader evaluation of PCA and multiple regression analysis (MRA) and to establish guidelines under which one approach is preferable to the other. Four geographic locations in the US with different climatic conditions were selected and synthetic data sequence representative of daily energy use in large institutional buildings were generated in each location using a linear model with outdoor temperature, outdoor specific humidity and solar radiation as the three regression variables. MRA and PCA approaches were then applied to these data sets and their relative performances were compared. Conditions under which PCA seems to perform better than MRA were identified and preliminary recommendations on the use of either modeling approach formulated. (orig.)

The Application of Classical and Neural Regression Models for the Valuation of Residential Real Estate

Directory of Open Access Journals (Sweden)

Mach Łukasz

2017-06-01

Full Text Available The research process aimed at building regression models, which helps to valuate residential real estate, is presented in the following article. Two widely used computational tools i.e. the classical multiple regression and regression models of artificial neural networks were used in order to build models. An attempt to define the utilitarian usefulness of the above-mentioned tools and comparative analysis of them is the aim of the conducted research. Data used for conducting analyses refers to the secondary transactional residential real estate market.

Tissue Trace Elements and Lipid Peroxidation in Breeding Female Bank Voles Myodes glareolus.

Science.gov (United States)

Bonda-Ostaszewska, Elżbieta; Włostowski, Tadeusz; Łaszkiewicz-Tiszczenko, Barbara

2018-04-27

Recent studies have demonstrated that reproduction reduces oxidative damage in various tissues of small mammal females. The present work was designed to determine whether the reduction of oxidative stress in reproductive bank vole females was associated with changes in tissue trace elements (iron, copper, zinc) that play an essential role in the production of reactive oxygen species. Lipid peroxidation (a marker of oxidative stress) and iron concentration in liver, kidneys, and skeletal muscles of reproducing bank vole females that weaned one litter were significantly lower than in non-reproducing females; linear regression analysis confirmed a positive relation between the tissue iron and lipid peroxidation. The concentrations of copper were significantly lower only in skeletal muscles of reproductive females and correlated positively with lipid peroxidation. No changes in tissue zinc were found in breeding females when compared with non-breeding animals. These data indicate that decreases in tissue iron and copper concentrations may be responsible for the reduction of oxidative stress in reproductive bank vole females.

Fat intake and injury in female runners.

Science.gov (United States)

Gerlach, Kristen E; Burton, Harold W; Dorn, Joan M; Leddy, John J; Horvath, Peter J

2008-01-03

Our purpose was to determine the relationship between energy intake, energy availability, dietary fat and lower extremity injury in adult female runners. We hypothesized that runners who develop overuse running-related injuries have lower energy intakes, lower energy availability and lower fat intake compared to non-injured runners. Eighty-six female subjects, running a minimum of 20 miles/week, completed a food frequency questionnaire and informed us about injury incidence over the next year. Injured runners had significantly lower intakes of total fat (63 +/- 20 vs. 80 +/- 50 g/d) and percentage of kilocalories from fat (27 +/- 5 vs. 30 +/- 8 %) compared with non-injured runners. A logistic regression analysis found that fat intake was the best dietary predictor, correctly identifying 64% of future injuries. Lower energy intake and lower energy availability approached, but did not reach, a significant association with overuse injury in this study. Fat intake is likely associated with injury risk in female runners. By documenting these associations, better strategies can be developed to reduce running injuries in women.

Tax System in Poland – Progressive or Regressive?

Directory of Open Access Journals (Sweden)

Jacek Tomkiewicz

2016-03-01

Full Text Available Purpose: To analyse the impact of the Polish fiscal regime on the general revenue of the country, and specifically to establish whether the cumulative tax burden borne by Polish households is progressive or regressive.Methodology: On the basis of Eurostat and OECD data, the author has analysed fiscal regimes in EU Member States and in OECD countries. The tax burden of households within different income groups has also been examined pursuant to applicable fiscal laws and data pertaining to the revenue and expenditure of households published by the Central Statistical Office (CSO.Conclusions: The fiscal regime in Poland is regressive; that is, the relative fiscal burden decreases as the taxpayer’s income increases.Research Implications: The article contributes to the on-going discussion on social cohesion, in particular with respect to economic policy instruments aimed at the redistribution of income within the economy.Originality: The author presents an analysis of data pertaining to fiscal policies in EU Member States and OECD countries and assesses the impact of the legal environment (fiscal regime and social security system in Poland on income distribution within the economy. The impact of the total tax burden (direct and indirect taxes, social security contributions on the economic situation of households from different income groups has been calculated using an original formula.

The non-condition logistic regression analysis of the reason of hypothyroidism after hyperthyroidism with 131I treatment

International Nuclear Information System (INIS)

Dang Yaping; Hu Guoying; Meng Xianwen

1994-01-01

There are many opinions on the reason of hypothyroidism after hyperthyroidism with 131 I treatment. In this respect, there are a few scientific analyses and reports. The non-condition logistic regression solved this problem successfully. It has a higher scientific value and confidence in the risk factor analysis. 748 follow-up patients' data were analysed by the non-condition logistic regression. The results shown that the half-life and 131 I dose were the main causes of the incidence of hypothyroidism. The degree of confidence is 92.4%

Spatial regression analysis on 32 years of total column ozone data

NARCIS (Netherlands)

Knibbe, J.S.; van der A, J.R.; de Laat, A.T.J.

2014-01-01

Multiple-regression analyses have been performed on 32 years of total ozone column data that was spatially gridded with a 1 × 1.5° resolution. The total ozone data consist of the MSR (Multi Sensor Reanalysis; 1979-2008) and 2 years of assimilated SCIAMACHY (SCanning Imaging Absorption spectroMeter

Comparison between young males and females with acute myocardial infarction

Directory of Open Access Journals (Sweden)

Ricardo Augusto Slaibi Conti

2002-11-01

Full Text Available OBJECTIVE: To assess the differences between young males and females after acute myocardial infarction. METHODS: We retrospectively studied 236 patients (54 females and 182 males after acute myocardial infarction and during hospital stay assessed the following parameters: risk factors; the treatment used; the pattern of coronary artery obstruction; left ventricular ejection fraction; complications; and, using a logistic regression model, the factors related to the occurrence of reinfarction and death. RESULTS: No significant difference was observed between the sexes in risk factors, pattern of coronary artery obstruction, and left ventricular function. The time interval between symptom onset and treatment was longer in females (p=0.03, who underwent thrombolysis (p=0.01 and angioplasty (p=0.03 less frequently than males did, but not myocardial revascularization. Female sex (OR = 5.98 and diabetes (OR = 14.52 were independent factors related to the occurrence of reinfarction and death. CONCLUSION: Young males and females after acute myocardial infarction did not differ in coronary risk factors, and clinical and hemodynamic characteristics. Females had their treatment started later, and they underwent chemical thrombolysis and angioplasty less frequently than males did. Female sex and diabetes were related to the occurrence of reinfarction and death.

Economic Analyses of Ware Yam Production in Orlu Agricultural ...

African Journals Online (AJOL)

Economic Analyses of Ware Yam Production in Orlu Agricultural Zone of Imo State. ... International Journal of Agriculture and Rural Development ... statistics, gross margin analysis, marginal analysis and multiple regression analysis. Results ...

Quantile regression for the statistical analysis of immunological data with many non-detects.

Science.gov (United States)

Eilers, Paul H C; Röder, Esther; Savelkoul, Huub F J; van Wijk, Roy Gerth

2012-07-07

Immunological parameters are hard to measure. A well-known problem is the occurrence of values below the detection limit, the non-detects. Non-detects are a nuisance, because classical statistical analyses, like ANOVA and regression, cannot be applied. The more advanced statistical techniques currently available for the analysis of datasets with non-detects can only be used if a small percentage of the data are non-detects. Quantile regression, a generalization of percentiles to regression models, models the median or higher percentiles and tolerates very high numbers of non-detects. We present a non-technical introduction and illustrate it with an implementation to real data from a clinical trial. We show that by using quantile regression, groups can be compared and that meaningful linear trends can be computed, even if more than half of the data consists of non-detects. Quantile regression is a valuable addition to the statistical methods that can be used for the analysis of immunological datasets with non-detects.

Gender Gaps in Mathematics, Science and Reading Achievements in Muslim Countries: A Quantile Regression Approach

Science.gov (United States)

Shafiq, M. Najeeb

2013-01-01

Using quantile regression analyses, this study examines gender gaps in mathematics, science, and reading in Azerbaijan, Indonesia, Jordan, the Kyrgyz Republic, Qatar, Tunisia, and Turkey among 15-year-old students. The analyses show that girls in Azerbaijan achieve as well as boys in mathematics and science and overachieve in reading. In Jordan,…

Mindfulness and eating behaviour styles in morbidly obese males and females.

Science.gov (United States)

Ouwens, M A; Schiffer, A A; Visser, L I; Raeijmaekers, N J C; Nyklíček, I

2015-04-01

Morbid obesity is a highly prevalent condition that is associated with a high risk of various diseases and high health care costs. Understanding determinants of eating behaviours that are characteristic of many morbidly obese persons is important for the development of new interventions aimed at changing eating behaviour after bariatric surgery. Dispositional mindfulness seems promising as one such potential determinant. Therefore, the association between mindfulness and eating behaviour was examined in females and males with morbid obesity. Outpatients with morbid obesity who were candidates for bariatric surgery (N = 335; 78.8% female) completed the Dutch Eating Behaviour Questionnaire (DEBQ), the Freiburg Mindfulness Inventory (FMI) and the Hospital Anxiety and Depression Scale (HADS), in addition to the collection of relevant demographic and medical data. Three separate multiple regression analyses with three eating behaviour styles (restrained, emotional, external) as dependent variables showed that mindfulness was positively associated with restrained eating behaviour (Beta = .28, p ≤ .001), and negatively associated with emotional (Beta = -.22, p ≤ .001) and external (Beta = -.32, p ≤ .001) eating behaviours, independent of sex, age, educational level, Body Mass Index and affective symptoms. Dispositional mindfulness was associated with more restrained, and less emotional and external eating behaviour in morbidly obese outpatients, above and beyond affective symptoms. Future studies, establishing the causal direction of the associations, are needed. Copyright © 2014 Elsevier Ltd. All rights reserved.

Redefining Female Desire: Angela Carter's Bloody Chamber

Directory of Open Access Journals (Sweden)

Sabrina Antonella Abeni

2014-03-01

This article analyses some passages of those tales, combining them with the ideas expressed by the author in her famous essay, demonstrating the originality and unconventionality of her interpretation of female desire, subject to misunderstanding and disputes, but strongly appreciated in recent years .

Area under the curve predictions of dalbavancin, a new lipoglycopeptide agent, using the end of intravenous infusion concentration data point by regression analyses such as linear, log-linear and power models.

Science.gov (United States)

Bhamidipati, Ravi Kanth; Syed, Muzeeb; Mullangi, Ramesh; Srinivas, Nuggehally

2018-02-01

1. Dalbavancin, a lipoglycopeptide, is approved for treating gram-positive bacterial infections. Area under plasma concentration versus time curve (AUC inf ) of dalbavancin is a key parameter and AUC inf /MIC ratio is a critical pharmacodynamic marker. 2. Using end of intravenous infusion concentration (i.e. C max ) C max versus AUC inf relationship for dalbavancin was established by regression analyses (i.e. linear, log-log, log-linear and power models) using 21 pairs of subject data. 3. The predictions of the AUC inf were performed using published C max data by application of regression equations. The quotient of observed/predicted values rendered fold difference. The mean absolute error (MAE)/root mean square error (RMSE) and correlation coefficient (r) were used in the assessment. 4. MAE and RMSE values for the various models were comparable. The C max versus AUC inf exhibited excellent correlation (r > 0.9488). The internal data evaluation showed narrow confinement (0.84-1.14-fold difference) with a RMSE models predicted AUC inf with a RMSE of 3.02-27.46% with fold difference largely contained within 0.64-1.48. 5. Regardless of the regression models, a single time point strategy of using C max (i.e. end of 30-min infusion) is amenable as a prospective tool for predicting AUC inf of dalbavancin in patients.

Predictors of Internet use for health information among male and female Internet users: Findings from the 2009 Taiwan National Health Interview Survey.

Science.gov (United States)

Koo, Malcolm; Lu, Ming-Chi; Lin, Shih-Chun

2016-10-01

The Internet is an increasingly important source of health information for the general population. Both preventive health behavior and Internet use are known to be different between men and women. However, few studies have compared predictors of Internet use for health information between the sexes. To investigate the prevalence and predictors of Internet use for health information among male and female adult Internet users using data from a population-based survey in Taiwan. Respondents between the ages of 20-65 years were identified from the dataset of the 2009 Taiwan National Health Interview Survey. The outcome variable of the study, the utilization of the Internet for health information, was ascertained by asking whether the respondent had ever used the Internet to search for health information or obtain health services. Univariate and multivariate logistic regression analyses were conducted separately for men and women to evaluate factors associated with the use of Internet for health information. Of the 2741 adults aged 20-65 years who had ever used the Internet, 1766 (64.4%) of them had used it for health information or services. Multivariate logistic regression analyses showed that a higher educational level (adjusted odds ratio [AOR]=3.60, Pused Western medicine services in the past month (AOR=1.51, P=0.005) were significantly associated with health information use in male Internet users. On the other hand, age between 20-44.9 years (AOR=1.87, PInternet users. This secondary data analysis of a representative sample of Taiwan population revealed that a similar but not identical set of independent factors was associated with the use of Internet for health information between male and female Internet users. Copyright © 2016. Published by Elsevier Ireland Ltd.

Logistic Regression in the Identification of Hazards in Construction

Science.gov (United States)

Drozd, Wojciech

2017-10-01

The construction site and its elements create circumstances that are conducive to the formation of risks to safety during the execution of works. Analysis indicates the critical importance of these factors in the set of characteristics that describe the causes of accidents in the construction industry. This article attempts to analyse the characteristics related to the construction site, in order to indicate their importance in defining the circumstances of accidents at work. The study includes sites inspected in 2014 - 2016 by the employees of the District Labour Inspectorate in Krakow (Poland). The analysed set of detailed (disaggregated) data includes both quantitative and qualitative characteristics. The substantive task focused on classification modelling in the identification of hazards in construction and identifying those of the analysed characteristics that are important in an accident. In terms of methodology, resource data analysis using statistical classifiers, in the form of logistic regression, was the method used.

The risk of cirrhosis in non-alcohol drinkers is greater in female than male betel nut chewers.

Science.gov (United States)

Chu, Yu-Hua; Wang, Lee; Ko, Pei-Chieh; Lan, Shou-Jen; Liaw, Yung-Po

2018-02-02

The association of betel nut with liver cirrhosis among alcohol drinkers has been clearly shown. However, very few studies have shown such an association among non-alcohol drinkers. The aim of this study was to assess the relationship between betel nut chewing and cirrhosis among non-alcohol drinkers. This study retrospectively analyzed data retrieved from the 2012 Adult Preventive Medical Services and the National Health Insurance Research Datasets in Taiwan. Participants' information included physical examination and lifestyle, alongside laboratory tests. Betel nut chewers were grouped into three categories: never, occasional and frequent. Diseases were diagnosed using the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM). Initially, 1573024 adults aged 40 years and above who engaged in the free adult preventive medical services in 2012 were recruited. However, only 1065246 of them were included in the analysis. Chi-square test and logistic regression were used for the analyses. After multivariable adjustments, there were significant relationships between cirrhosis and betel nut chewing in both sexes (P-trend betel nut chewing and cirrhosis in both male and female non-alcohol drinkers. The risk of cirrhosis was greater in female than male chewers.

A comparison of Cox and logistic regression for use in genome-wide association studies of cohort and case-cohort design.

Science.gov (United States)

Staley, James R; Jones, Edmund; Kaptoge, Stephen; Butterworth, Adam S; Sweeting, Michael J; Wood, Angela M; Howson, Joanna M M

2017-06-01

Logistic regression is often used instead of Cox regression to analyse genome-wide association studies (GWAS) of single-nucleotide polymorphisms (SNPs) and disease outcomes with cohort and case-cohort designs, as it is less computationally expensive. Although Cox and logistic regression models have been compared previously in cohort studies, this work does not completely cover the GWAS setting nor extend to the case-cohort study design. Here, we evaluated Cox and logistic regression applied to cohort and case-cohort genetic association studies using simulated data and genetic data from the EPIC-CVD study. In the cohort setting, there was a modest improvement in power to detect SNP-disease associations using Cox regression compared with logistic regression, which increased as the disease incidence increased. In contrast, logistic regression had more power than (Prentice weighted) Cox regression in the case-cohort setting. Logistic regression yielded inflated effect estimates (assuming the hazard ratio is the underlying measure of association) for both study designs, especially for SNPs with greater effect on disease. Given logistic regression is substantially more computationally efficient than Cox regression in both settings, we propose a two-step approach to GWAS in cohort and case-cohort studies. First to analyse all SNPs with logistic regression to identify associated variants below a pre-defined P-value threshold, and second to fit Cox regression (appropriately weighted in case-cohort studies) to those identified SNPs to ensure accurate estimation of association with disease.

FEMALE LABOR WORKING INTENSITY: A STUDY CASE IN A CONSTRUCTION JOB

Directory of Open Access Journals (Sweden)

Agus Suseno

2015-12-01

Full Text Available This paper analyzes demographic and socio-economic characteristics of female labor in Bantul District. The characteristics are measured by their education, ages, marital status, number of children, house location, distance from workplace, and salary. The contribution of female labor to their families are analyzed by arithmetic mean. To model the behaviour of female labor work intensity, this paper uses salary, number of children, distance to work location, husband income, and dummy variables on free rice program, health insurance program, and house location. Using a multiple regression model, it finds that variables significantly increase work intensity are salary and husband’s income, while those significantly decreases work intensity are number of children, distance to workplace, and rice free program.

QUANTITATIVE DIFFERENCES WITHIN ANTHROPOMETRIC SPACE WITH FEMALE STUDENTS AT HIGH SCHOOL

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Viktor Mitrevski

2011-03-01

Full Text Available The aim of this research is to determine the differences within anthropometric space with female students attending the regular class activity in physical education at school, the activities being held in different working conditions. Depending on these conditions the female students are divided into three (3 sub-examples, or the research includes a total of 183 entities. The analyses of results makes use of seven anthropometric parameters four of which treat the circular dimension and three treat subcutaneous fatty tissue. In order to determine differences between the three groups of female students according to the working conditions in class, the following analyses are used: univariate analysis of variance (ANOVA, t-test, and multivariate analysis of variance (MANOVA. The obtained data pointsat statistically significant differences between the groups within the whole space of anthropometric analysis. Arithmetic means are analysed between the groups with regard to all variables, and between the arithmetic means statistically significant differences are only determined with the variable of average volume of stomach (ASOS, whereas with the rest of variables statistically significant differences are not marked.

Use of multiple linear regression and logistic regression models to investigate changes in birthweight for term singleton infants in Scotland.

Science.gov (United States)

Bonellie, Sandra R

2012-10-01

To illustrate the use of regression and logistic regression models to investigate changes over time in size of babies particularly in relation to social deprivation, age of the mother and smoking. Mean birthweight has been found to be increasing in many countries in recent years, but there are still a group of babies who are born with low birthweights. Population-based retrospective cohort study. Multiple linear regression and logistic regression models are used to analyse data on term 'singleton births' from Scottish hospitals between 1994-2003. Mothers who smoke are shown to give birth to lighter babies on average, a difference of approximately 0.57 Standard deviations lower (95% confidence interval. 0.55-0.58) when adjusted for sex and parity. These mothers are also more likely to have babies that are low birthweight (odds ratio 3.46, 95% confidence interval 3.30-3.63) compared with non-smokers. Low birthweight is 30% more likely where the mother lives in the most deprived areas compared with the least deprived, (odds ratio 1.30, 95% confidence interval 1.21-1.40). Smoking during pregnancy is shown to have a detrimental effect on the size of infants at birth. This effect explains some, though not all, of the observed socioeconomic birthweight. It also explains much of the observed birthweight differences by the age of the mother.   Identifying mothers at greater risk of having a low birthweight baby as important implications for the care and advice this group receives. © 2012 Blackwell Publishing Ltd.

1 original article diverse genetic subtypes of hiv-1 among female sex

African Journals Online (AJOL)

boaz

Keywords: Diverse, HIV, subtypes, Female Sex workers and Vaccine ... significant probability that infection with this subtype occurred with a short incubation period (p< 0.05). Conclusion: This study .... regression was used to adjust for potential cofounders. .... TABLE 2: DISTRIBUTION OF HIV-1 SUBTYPES AMONG FSWS.

Time-adaptive quantile regression

DEFF Research Database (Denmark)

Møller, Jan Kloppenborg; Nielsen, Henrik Aalborg; Madsen, Henrik

2008-01-01

and an updating procedure are combined into a new algorithm for time-adaptive quantile regression, which generates new solutions on the basis of the old solution, leading to savings in computation time. The suggested algorithm is tested against a static quantile regression model on a data set with wind power......An algorithm for time-adaptive quantile regression is presented. The algorithm is based on the simplex algorithm, and the linear optimization formulation of the quantile regression problem is given. The observations have been split to allow a direct use of the simplex algorithm. The simplex method...... production, where the models combine splines and quantile regression. The comparison indicates superior performance for the time-adaptive quantile regression in all the performance parameters considered....

Psychosocial stress factors, including the relationship with the coach, and their influence on acute and overuse injury risk in elite female football players.

Science.gov (United States)

Pensgaard, Anne Marte; Ivarsson, Andreas; Nilstad, Agnethe; Solstad, Bård Erlend; Steffen, Kathrin

2018-01-01

The relationship between specific types of stressors (eg, teammates, coach) and acute versus overuse injuries is not well understood. To examine the roles of different types of stressors as well as the effect of motivational climate on the occurrence of acute and overuse injuries. Players in the Norwegian elite female football league (n=193 players from 12 teams) participated in baseline screening tests prior to the 2009 competitive football season. As part of the screening, we included the Life Event Survey for Collegiate Athletes and the Perceived Motivational Climate in Sport Questionnaire (Norwegian short version). Acute and overuse time-loss injuries and exposure to training and matches were recorded prospectively in the football season using weekly text messaging. Data were analysed with Bayesian logistic regression analyses. Using Bayesian logistic regression analyses, we showed that perceived negative life event stress from teammates was associated with an increased risk of acute injuries (OR=1.23, 95% credibility interval (1.01 to 1.48)). There was a credible positive association between perceived negative life event stress from the coach and the risk of overuse injuries (OR=1.21, 95% credibility interval (1.01 to 1.45)). Players who report teammates as a source of stress have a greater risk of sustaining an acute injury, while players reporting the coach as a source of stress are at greater risk of sustaining an overuse injury. Motivational climate did not relate to increased injury occurrence.

Intimate Violence as It Relates to Risky Sexual Behavior Among At-Risk Females.

Science.gov (United States)

Hill, Danielle C; Stein, L A R; Rossi, Joseph S; Magill, Molly; Clarke, Jennifer G

2017-10-05

Rates of sexually transmitted infections (STIs) among adolescents are on the rise. The majority of adolescents who contract STIs do so through risky sexual behavior. Previous literature has identified multiple correlates of risky sexual behaviors among adolescents, including physical and sexual victimization, mental health concerns, and substance use. Few studies, however, have examined these relationships together in a comprehensive model. The primary purpose of this study was to examine whether relationship violence was related to risky sexual behavior, and whether mental health symptoms and substance use mediated this relationship. A cross-sectional design was used, and adolescent females (N = 179), recruited from social service agencies, were 18.9 years old on average and were 37.2% White, 19.3% Black, 37.9% multiracial, and 5.6% other. Regression results revealed that females who were physically assaulted and sexually victimized by their intimate partners did engage in more sex without condoms. Mediational analyses indicated that PTSD symptoms significantly influenced the relationship between (1) physical assault and risky sexual behavior and (2) sexual victimization and risky sexual behavior. Contrary to expectations, PTSD may act to reduce risk perhaps by reducing interest in sex. It is important to address victimization, PTSD, and sexual risk in young women. More work is needed to understand these complex relationships using longitudinal designs. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Social representations of female orgasm.

Science.gov (United States)

Lavie-Ajayi, Maya; Joffe, Hélène

2009-01-01

This study examines women's social representations of female orgasm. Fifty semi-structured interviews were conducted with British women. The data were thematically analysed and compared with the content of female orgasm-related writing in two women's magazines over a 30-year period. The results indicate that orgasm is deemed the goal of sex with emphasis on its physiological dimension. However, the women and the magazines graft onto this scientifically driven representation the importance of relational and emotive aspects of orgasm. For the women, particularly those who experience themselves as having problems with orgasm, the scientifically driven representations induce feelings of failure, but are also resisted. The findings highlight the role played by the social context in women's subjective experience of their sexual health.

Dysmenorrhea and self-care strategies in Iranian female students: a regression modeling of pain severity and underlying factors.

Science.gov (United States)

Ghaderi, Fariba; Asghari Jafarabadi, Mohammad; Mohseni Bandpei, Mohammad Ali

2016-07-18

Dysmenorrhea is the most common gynecologic condition experienced by menstruating women and has significant medical and psychosocial impacts. The objective of this study was to determine the prevalence and the problems related to menstruation, self-care strategies and their relations with pain severity in female students of Tabriz University of Medical Sciences. This cross sectional study was carried out among 197 unmarried and healthy female medical students during April 2013 to July 2013. A standardized questionnaire was given to participants to complete, which included questions about demographic information, prevalence and severity of pain, self-care strategies and its effectiveness. The prevalence of dysmenorrhea was 98.4% (95% confidence interval=97.6%-99.2%). Almost 76% (149) of students reported limitation of daily activities. The most common method for relief pain were: taking analgesics (64.3%), rest (61.9%), taking herbal medicine (11.7%), and applying hot compress on area of pain (22.3%). Obtaining information about self-care strategies offered from family and friends 79 (41%) were more common than scientific articles 56 (28.7%) and the Internet 43 (22%). Significant relations were observed between self-care strategies' scales and pain severity. The results indicated that dysmenorrhea was highly prevalent among female medical students and is a major problem affecting their life. A variety of treatments is available for dysmenorrhea but most of the participants did not seek medical advice and they used self-care strategies. However, further studies focusing on health education and routine screening for menstrual problems are recommended.

Prevalence and influence factors of suicidal ideation among females and males in Northwestern urban China: a population-based epidemiological study.

Science.gov (United States)

Xu, Huiwen; Zhang, Weijun; Wang, Xiaohua; Yuan, Jiaqi; Tang, Xinfeng; Yin, Yi; Zhang, Shengfa; Zhou, Huixuan; Qu, Zhiyong; Tian, Donghua

2015-09-25

Suicide is an urgent public health challenge for China. This study aims to examine the prevalence, influence factors, and gender differences of suicidal ideation among general population in Northwestern Urban China. Data used in this study were derived from the third wave of a cohort study of a randomized community sample with 4291 participants (≥ 20 years) in 2008 in Lanzhou City and Baiyin City, Gansu Province. Data were collected via face-to-face interview by the trained interviewers. Descriptive analyses, chi-square tests and multivariate logistic regressions were performed by using Stata 12.0, as needed. The prevalence of 12-month suicidal ideation was 4.29%, there was no significant difference between males and females [5.04% vs 3.62%, Adjusted Odds Ratio (AOR) = 0.83, p = 0.351]. Several risk factors for suicidal ideation were confirmed, including being unmarried (AOR = 1.55, p = 0.030), having depression symptoms (AOR = 2.33, p married (unmarried vs married, AOR = 1.84, p = 0.027, for females; no difference for males), feeling hopeless (hopless vs hopeful, AOR = 1.92, p = 0.06, for females; no difference for males), having other insurances (having other insurances vs having basic employee medical insurance, AOR = 1.92, p = 0.044, for males; no difference for females), having debts (having debts vs no debts, AOR = 2.69, p = 0.001, for males; no difference for females), currently smoking (smoking vs nonsmoking, AOR = 3.01, p = 0.019 for females, no difference for males), and currently drinking (drinking vs nondrinking, AOR =2.01, p = 0.022, for males; no difference for females). These findings suggested that comprehensive suicide prevention strategies should be developed or strengthened in order to prevent suicide ideation in China, and the gender-specific differences need to be explored through further researches.

Can sexual selection drive female life histories? A comparative study on Galliform birds

OpenAIRE

Kolm, N.; Stein, R. W.; Mooers, A. O.; Verspoor, J. J.; Cunningham, E. J. A.

2007-01-01

Sexual selection has been identified as a major evolutionary force shaping male life history traits but its impact on female life history evolution is less clear. Here we examine the impact of sexual selection on three key female traits (body size, egg size and clutch size) in Galliform birds. Using comparative independent contrast analyses and directional DISCRETE analyses, based on published data and a new genera-level supertree phylogeny of Galliform birds, we investigated how sexual selec...

Married women's negotiation for safer sexual intercourse in Kenya: Does experience of female genital mutilation matter?

Science.gov (United States)

Chai, Xiangnan; Sano, Yujiro; Kansanga, Moses; Baada, Jemima; Antabe, Roger

2017-12-01

Married women's ability to negotiate for safer sex is important for HIV prevention in sub-Saharan Africa, including Kenya. Yet, its relationship to female genital mutilation is rarely explored, although female genital mutilation has been described as a social norm and marker of womanhood that can control women's sexuality. Drawing on the social normative influence theory, this study addressed this void in the literature. We analysed data from the 2014 Kenya Demographic and Health Survey using logistic regression. Our sample included 8,602 married women. Two indicators of safer sex, namely the ability to refuse sex and the ability to ask for condom use, were explored. We found that women who had undergone genital mutilation were significantly less likely to report that they can refuse sex (OR=0.87; p<.05) and that they can ask for condom use during sexual intercourse (OR=0.62; p<.001) than their counterparts who had not undergone genital mutilation, while controlling for theoretically relevant variables. Our findings indicate that the experience of female genital mutilation may influence married women's ability to negotiate for safer sex through gendered socialization and expectations. Based on these findings, several policy implications are suggested. For instance, culturally sensitive programmes are needed that target both married women who have undergone genital mutilation and their husbands to understand the importance of safer sexual practices within marriage. Copyright © 2017. Published by Elsevier B.V.

Condition-dependent clutch desertion in Great Tit (Parus major) females subjected to human disturbance

OpenAIRE

2011-01-01

Abstract Nest desertion behaviour in relation to body condition and timing of breeding was studied in Great Tit (Parus major) females during two breeding seasons. Desertion, most likely unintentionally provoked by catching females during the incubation period, occurred at a very high rate with 41.2 and 25.6% of deserted first clutches in the two study years. The association between desertion probability, body condition (index calculated as residuals from the regression of body mass...

Econometric analysis of realised covariation: high frequency covariance, regression and correlation in financial economics

OpenAIRE

Ole E. Barndorff-Nielsen; Neil Shephard

2002-01-01

This paper analyses multivariate high frequency financial data using realised covariation. We provide a new asymptotic distribution theory for standard methods such as regression, correlation analysis and covariance. It will be based on a fixed interval of time (e.g. a day or week), allowing the number of high frequency returns during this period to go to infinity. Our analysis allows us to study how high frequency correlations, regressions and covariances change through time. In particular w...

Perceptions of Individual and Family Functioning Among Deployed Female National Guard Members.

Science.gov (United States)

Kelly, Patricia J; Cheng, An-Lin; Berkel, LaVerne A; Nilsson, Johanna

2016-08-01

Females currently make up 15% of U.S. military service members. Minimal attention has been paid to families of female National Guard members who have been deployed and their subsequent reintegration challenges. This cross-sectional Internet-based survey of female members of four National Guard units compared those who were and were not deployed. Instruments, guided by the variables of the Family Resilience Model, measured individual, family, and deployment-related factors. Bivariate analysis and ordinal logistic regression were done to assess differences between the groups. Of the 239 National Guard members surveyed, deployed women (n = 164) had significantly higher levels of posttraumatic stress disorder (PTSD; p family functioning were higher among deployed when compared with never deployed women. Results indicate community interventions that focus on strengthening coping skills of female Guard members would be useful for this population. © The Author(s) 2016.

THE IMPACT OF FEMALE DIRECTORS ON FIRM PERFORMANCE: EVIDENCE FROM INDONESIA

Directory of Open Access Journals (Sweden)

Triana

2017-01-01

Full Text Available This research shows the impact of female directors on firm performance in Indonesia by using as its sample the public companies listed on the Indonesian Stock Exchange (IDX from 2011 until 2015. There were 347 companies, with 1,735 samples observed. This research uses the multiple regression method. The model is a modified model from 9 recent articles published between 2012 and 2015. The empirical result shows that a female director has a positive significant effect on firm performance. The control variables, consisting of leverage, firm size and firm age have negative significance for firm performance. This research is conducted across 9 sectors of industrial classification, which support the International Finance Corporation (IFC in increasing the number of female directors in Indonesia. For managers, this research will promote gender development in the boardroom, female executive training programmes as well as female representation on boards of directors. For regulators, this research may provide a contribution to gender representation in board’s policies, rules and regulations. This research can build awareness of women’s contributions to firms and encourage a greater female presence in the boardroom.

Regression analysis by example

CERN Document Server

Chatterjee, Samprit

2012-01-01

Praise for the Fourth Edition: ""This book is . . . an excellent source of examples for regression analysis. It has been and still is readily readable and understandable."" -Journal of the American Statistical Association Regression analysis is a conceptually simple method for investigating relationships among variables. Carrying out a successful application of regression analysis, however, requires a balance of theoretical results, empirical rules, and subjective judgment. Regression Analysis by Example, Fifth Edition has been expanded

Applied logistic regression

CERN Document Server

Hosmer, David W; Sturdivant, Rodney X

2013-01-01

 A new edition of the definitive guide to logistic regression modeling for health science and other applications This thoroughly expanded Third Edition provides an easily accessible introduction to the logistic regression (LR) model and highlights the power of this model by examining the relationship between a dichotomous outcome and a set of covariables. Applied Logistic Regression, Third Edition emphasizes applications in the health sciences and handpicks topics that best suit the use of modern statistical software. The book provides readers with state-of-

Privacy-Preserving Distributed Linear Regression on High-Dimensional Data

Directory of Open Access Journals (Sweden)

Gascón Adrià

2017-10-01

Full Text Available We propose privacy-preserving protocols for computing linear regression models, in the setting where the training dataset is vertically distributed among several parties. Our main contribution is a hybrid multi-party computation protocol that combines Yao’s garbled circuits with tailored protocols for computing inner products. Like many machine learning tasks, building a linear regression model involves solving a system of linear equations. We conduct a comprehensive evaluation and comparison of different techniques for securely performing this task, including a new Conjugate Gradient Descent (CGD algorithm. This algorithm is suitable for secure computation because it uses an efficient fixed-point representation of real numbers while maintaining accuracy and convergence rates comparable to what can be obtained with a classical solution using floating point numbers. Our technique improves on Nikolaenko et al.’s method for privacy-preserving ridge regression (S&P 2013, and can be used as a building block in other analyses. We implement a complete system and demonstrate that our approach is highly scalable, solving data analysis problems with one million records and one hundred features in less than one hour of total running time.

Normalization Ridge Regression in Practice I: Comparisons Between Ordinary Least Squares, Ridge Regression and Normalization Ridge Regression.

Science.gov (United States)

Bulcock, J. W.

The problem of model estimation when the data are collinear was examined. Though the ridge regression (RR) outperforms ordinary least squares (OLS) regression in the presence of acute multicollinearity, it is not a problem free technique for reducing the variance of the estimates. It is a stochastic procedure when it should be nonstochastic and it…

Quantile regression for the statistical analysis of immunological data with many non-detects

NARCIS (Netherlands)

Eilers, P.H.C.; Roder, E.; Savelkoul, H.F.J.; Wijk, van R.G.

2012-01-01

Background Immunological parameters are hard to measure. A well-known problem is the occurrence of values below the detection limit, the non-detects. Non-detects are a nuisance, because classical statistical analyses, like ANOVA and regression, cannot be applied. The more advanced statistical

Quantile regression for the statistical analysis of immunological data with many non-detects

NARCIS (Netherlands)

P.H.C. Eilers (Paul); E. Röder (Esther); H.F.J. Savelkoul (Huub); R. Gerth van Wijk (Roy)

2012-01-01

textabstractBackground: Immunological parameters are hard to measure. A well-known problem is the occurrence of values below the detection limit, the non-detects. Non-detects are a nuisance, because classical statistical analyses, like ANOVA and regression, cannot be applied. The more advanced

Risky Sexual Behavior among Rural Female Adolescents in Malaysia: A Limited Role of Protective Factors

OpenAIRE

Ahmadian, Maryam; Hamsan, Hanina H.; Abdullah, Haslinda; Samah, Asnarulkhadi Abu; Noor, Amna Md

2014-01-01

Purpose: This paper presents the findings of a cross-sectional survey on the risk and protective factors of premarital sexual behavior among rural female adolescents in Peninsular Malaysia. Methods: We investigated data on 770 female respondents aged 13-17 years in rural areas to identify predictive factors for premarital sexual intercourse. Data were analyzed using bivariate and multivariate regression. Specific socio-demographic factors, psychological and family domains, peer delinquency, a...

Patterns of medicinal plant use: an examination of the Ecuadorian Shuar medicinal flora using contingency table and binomial analyses.

Science.gov (United States)

Bennett, Bradley C; Husby, Chad E

2008-03-28

Botanical pharmacopoeias are non-random subsets of floras, with some taxonomic groups over- or under-represented. Moerman [Moerman, D.E., 1979. Symbols and selectivity: a statistical analysis of Native American medical ethnobotany, Journal of Ethnopharmacology 1, 111-119] introduced linear regression/residual analysis to examine these patterns. However, regression, the commonly-employed analysis, suffers from several statistical flaws. We use contingency table and binomial analyses to examine patterns of Shuar medicinal plant use (from Amazonian Ecuador). We first analyzed the Shuar data using Moerman's approach, modified to better meet requirements of linear regression analysis. Second, we assessed the exact randomization contingency table test for goodness of fit. Third, we developed a binomial model to test for non-random selection of plants in individual families. Modified regression models (which accommodated assumptions of linear regression) reduced R(2) to from 0.59 to 0.38, but did not eliminate all problems associated with regression analyses. Contingency table analyses revealed that the entire flora departs from the null model of equal proportions of medicinal plants in all families. In the binomial analysis, only 10 angiosperm families (of 115) differed significantly from the null model. These 10 families are largely responsible for patterns seen at higher taxonomic levels. Contingency table and binomial analyses offer an easy and statistically valid alternative to the regression approach.

Body Image Concerns and Contingent Self-Esteem in Male and Female College Students.

Science.gov (United States)

Grossbard, Joel R; Lee, Christine M; Neighbors, Clayton; Larimer, Mary E

2009-02-01

Body dissatisfaction in females, and to a lesser extent males, is associated with low self-esteem, depression, and eating disorders. This research examined gender as a moderator of the association between contingent self-esteem and body image concerns, including weight and muscularity. Participants included 359 (59.1% female) heavy drinking first-year U.S. undergraduate students who completed a survey assessing health-related risk behaviors. Hierarchical multiple regression was used to examine relations among gender, contingent self-esteem, and body image. Females reported higher levels of contingent self-esteem and greater concerns about their weight, although males reported a greater drive for muscularity. The relationship between contingent self-esteem and weight concerns was stronger among females, and for males, greater contingent self-esteem was associated with a greater drive for muscularity.

Consistent Condom Use by Female Sex Workers in Kolkata, India: Testing Theories of Economic Insecurity, Behavior Change, Life Course Vulnerability and Empowerment.

Science.gov (United States)

Fehrenbacher, Anne E; Chowdhury, Debasish; Ghose, Toorjo; Swendeman, Dallas

2016-10-01

Consistent condom use (CCU) is the primary HIV/STI prevention option available to sex workers globally but may be undermined by economic insecurity, life-course vulnerabilities, behavioral factors, disempowerment, or lack of effective interventions. This study examines predictors of CCU in a random household survey of brothel-based female sex workers (n = 200) in two neighborhoods served by Durbar (the Sonagachi Project) in Kolkata, India. Multivariate logistic regression analyses indicated that CCU was significantly associated with perceived HIV risk, community mobilization participation, working more days in sex work, and higher proportion of occasional clients to regular clients. Exploratory analyses stratifying by economic insecurity indicators (i.e., debt, savings, income, housing security) indicate that perceived HIV risk and community mobilization were only associated with CCU for economically secure FSW. Interventions with FSW must prioritize economic security and access to social protections as economic insecurity may undermine the efficacy of more direct condom use intervention strategies.

Vector regression introduced

Directory of Open Access Journals (Sweden)

Mok Tik

2014-06-01

Full Text Available This study formulates regression of vector data that will enable statistical analysis of various geodetic phenomena such as, polar motion, ocean currents, typhoon/hurricane tracking, crustal deformations, and precursory earthquake signals. The observed vector variable of an event (dependent vector variable is expressed as a function of a number of hypothesized phenomena realized also as vector variables (independent vector variables and/or scalar variables that are likely to impact the dependent vector variable. The proposed representation has the unique property of solving the coefficients of independent vector variables (explanatory variables also as vectors, hence it supersedes multivariate multiple regression models, in which the unknown coefficients are scalar quantities. For the solution, complex numbers are used to rep- resent vector information, and the method of least squares is deployed to estimate the vector model parameters after transforming the complex vector regression model into a real vector regression model through isomorphism. Various operational statistics for testing the predictive significance of the estimated vector parameter coefficients are also derived. A simple numerical example demonstrates the use of the proposed vector regression analysis in modeling typhoon paths.

Bodily integrity and male and female circumcision.

NARCIS (Netherlands)

Dekkers, W.J.M.; Hoffer, C.; Wils, J.P.

2005-01-01

This paper explores the ambiguous notion of bodily integrity, focusing on male and female circumcision. In the empirical part of the study we describe and analyse the various meanings that are given to the notion of bodily integrity by people in their daily lives. In the philosophical part we

A note on the use of multiple linear regression in molecular ecology.

Science.gov (United States)

Frasier, Timothy R

2016-03-01

Multiple linear regression analyses (also often referred to as generalized linear models--GLMs, or generalized linear mixed models--GLMMs) are widely used in the analysis of data in molecular ecology, often to assess the relative effects of genetic characteristics on individual fitness or traits, or how environmental characteristics influence patterns of genetic differentiation. However, the coefficients resulting from multiple regression analyses are sometimes misinterpreted, which can lead to incorrect interpretations and conclusions within individual studies, and can propagate to wider-spread errors in the general understanding of a topic. The primary issue revolves around the interpretation of coefficients for independent variables when interaction terms are also included in the analyses. In this scenario, the coefficients associated with each independent variable are often interpreted as the independent effect of each predictor variable on the predicted variable. However, this interpretation is incorrect. The correct interpretation is that these coefficients represent the effect of each predictor variable on the predicted variable when all other predictor variables are zero. This difference may sound subtle, but the ramifications cannot be overstated. Here, my goals are to raise awareness of this issue, to demonstrate and emphasize the problems that can result and to provide alternative approaches for obtaining the desired information. © 2015 John Wiley & Sons Ltd.

Applied linear regression

CERN Document Server

Weisberg, Sanford

2013-01-01

Praise for the Third Edition ""...this is an excellent book which could easily be used as a course text...""-International Statistical Institute The Fourth Edition of Applied Linear Regression provides a thorough update of the basic theory and methodology of linear regression modeling. Demonstrating the practical applications of linear regression analysis techniques, the Fourth Edition uses interesting, real-world exercises and examples. Stressing central concepts such as model building, understanding parameters, assessing fit and reliability, and drawing conclusions, the new edition illus

Fat intake and injury in female runners

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Leddy John J

2008-01-01

Full Text Available Abstract Background Our purpose was to determine the relationship between energy intake, energy availability, dietary fat and lower extremity injury in adult female runners. We hypothesized that runners who develop overuse running-related injuries have lower energy intakes, lower energy availability and lower fat intake compared to non-injured runners. Methods Eighty-six female subjects, running a minimum of 20 miles/week, completed a food frequency questionnaire and informed us about injury incidence over the next year. Results Injured runners had significantly lower intakes of total fat (63 ± 20 vs. 80 ± 50 g/d and percentage of kilocalories from fat (27 ± 5 vs. 30 ± 8 % compared with non-injured runners. A logistic regression analysis found that fat intake was the best dietary predictor, correctly identifying 64% of future injuries. Lower energy intake and lower energy availability approached, but did not reach, a significant association with overuse injury in this study. Conclusion Fat intake is likely associated with injury risk in female runners. By documenting these associations, better strategies can be developed to reduce running injuries in women.

Sexual Knowledge, Attitudes and Practices of Female Undergraduate Students in Wuhan, China: The Only-Child versus Students with Siblings

OpenAIRE

Li, Shiyue; Chen, Rucheng; Cao, Yue; Li, Jingjing; Zuo, Dan; Yan, Hong

2013-01-01

OBJECTIVES: This study explored sexual knowledge, attitudes and practices of female only-child undergraduates and made a comparison with students with siblings. METHODS: Anonymously completed questionnaires were received from 4,769 female undergraduates, recruited using randomized cluster sampling by type of university and students' major and grade. Multivariate logistic regression was used to assess the effects of only-child on sexual knowledge, attitudes and practices among female undergrad...

Regression Models and Fuzzy Logic Prediction of TBM Penetration Rate

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Minh Vu Trieu

2017-03-01

Full Text Available This paper presents statistical analyses of rock engineering properties and the measured penetration rate of tunnel boring machine (TBM based on the data of an actual project. The aim of this study is to analyze the influence of rock engineering properties including uniaxial compressive strength (UCS, Brazilian tensile strength (BTS, rock brittleness index (BI, the distance between planes of weakness (DPW, and the alpha angle (Alpha between the tunnel axis and the planes of weakness on the TBM rate of penetration (ROP. Four (4 statistical regression models (two linear and two nonlinear are built to predict the ROP of TBM. Finally a fuzzy logic model is developed as an alternative method and compared to the four statistical regression models. Results show that the fuzzy logic model provides better estimations and can be applied to predict the TBM performance. The R-squared value (R2 of the fuzzy logic model scores the highest value of 0.714 over the second runner-up of 0.667 from the multiple variables nonlinear regression model.

Regression Models and Fuzzy Logic Prediction of TBM Penetration Rate

Science.gov (United States)

Minh, Vu Trieu; Katushin, Dmitri; Antonov, Maksim; Veinthal, Renno

2017-03-01

This paper presents statistical analyses of rock engineering properties and the measured penetration rate of tunnel boring machine (TBM) based on the data of an actual project. The aim of this study is to analyze the influence of rock engineering properties including uniaxial compressive strength (UCS), Brazilian tensile strength (BTS), rock brittleness index (BI), the distance between planes of weakness (DPW), and the alpha angle (Alpha) between the tunnel axis and the planes of weakness on the TBM rate of penetration (ROP). Four (4) statistical regression models (two linear and two nonlinear) are built to predict the ROP of TBM. Finally a fuzzy logic model is developed as an alternative method and compared to the four statistical regression models. Results show that the fuzzy logic model provides better estimations and can be applied to predict the TBM performance. The R-squared value (R2) of the fuzzy logic model scores the highest value of 0.714 over the second runner-up of 0.667 from the multiple variables nonlinear regression model.

SOCR Analyses: Implementation and Demonstration of a New Graphical Statistics Educational Toolkit

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Annie Chu

2009-04-01

Full Text Available The web-based, Java-written SOCR (Statistical Online Computational Resource toolshave been utilized in many undergraduate and graduate level statistics courses for sevenyears now (Dinov 2006; Dinov et al. 2008b. It has been proven that these resourcescan successfully improve students' learning (Dinov et al. 2008b. Being rst publishedonline in 2005, SOCR Analyses is a somewhat new component and it concentrate on datamodeling for both parametric and non-parametric data analyses with graphical modeldiagnostics. One of the main purposes of SOCR Analyses is to facilitate statistical learn-ing for high school and undergraduate students. As we have already implemented SOCRDistributions and Experiments, SOCR Analyses and Charts fulll the rest of a standardstatistics curricula. Currently, there are four core components of SOCR Analyses. Linearmodels included in SOCR Analyses are simple linear regression, multiple linear regression,one-way and two-way ANOVA. Tests for sample comparisons include t-test in the para-metric category. Some examples of SOCR Analyses' in the non-parametric category areWilcoxon rank sum test, Kruskal-Wallis test, Friedman's test, Kolmogorov-Smirno testand Fligner-Killeen test. Hypothesis testing models include contingency table, Friedman'stest and Fisher's exact test. The last component of Analyses is a utility for computingsample sizes for normal distribution. In this article, we present the design framework,computational implementation and the utilization of SOCR Analyses.

Female Principals in Education: Breaking the Glass Ceiling in Spain

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Enrique Javier Diez Gutierrez

Full Text Available Abstract Spanish schools are characterised by having a high proportion of female staff. However, statistics show that a proportionately higher number of men hold leadership positions. The aim of this study was to analyse the reasons why this is so, and to determine the motivations and barriers that women encounter in attaining and exercising these positions of greater responsibility and power. Questionnaires were administered to 2,022 female teachers, 430 female principals and 322 male principals. In addition, semi-structured interviews were held with 60 female principals, 14 focus group discussions were held with female principals and 16 autobiographical narratives were compiled with female principals and school inspectors. The reasons identified were related to structural aspects linked to the patriarchal worldview that is still dominant in our society and culture. Nevertheless, we also found motivations among women for attaining and exercising leadership roles.

Understanding poisson regression.

Science.gov (United States)

Hayat, Matthew J; Higgins, Melinda

2014-04-01

Nurse investigators often collect study data in the form of counts. Traditional methods of data analysis have historically approached analysis of count data either as if the count data were continuous and normally distributed or with dichotomization of the counts into the categories of occurred or did not occur. These outdated methods for analyzing count data have been replaced with more appropriate statistical methods that make use of the Poisson probability distribution, which is useful for analyzing count data. The purpose of this article is to provide an overview of the Poisson distribution and its use in Poisson regression. Assumption violations for the standard Poisson regression model are addressed with alternative approaches, including addition of an overdispersion parameter or negative binomial regression. An illustrative example is presented with an application from the ENSPIRE study, and regression modeling of comorbidity data is included for illustrative purposes. Copyright 2014, SLACK Incorporated.

Alternative Methods of Regression

CERN Document Server

Birkes, David

2011-01-01

Of related interest. Nonlinear Regression Analysis and its Applications Douglas M. Bates and Donald G. Watts ".an extraordinary presentation of concepts and methods concerning the use and analysis of nonlinear regression models.highly recommend[ed].for anyone needing to use and/or understand issues concerning the analysis of nonlinear regression models." --Technometrics This book provides a balance between theory and practice supported by extensive displays of instructive geometrical constructs. Numerous in-depth case studies illustrate the use of nonlinear regression analysis--with all data s

Time series regression model for infectious disease and weather.

Science.gov (United States)

Imai, Chisato; Armstrong, Ben; Chalabi, Zaid; Mangtani, Punam; Hashizume, Masahiro

2015-10-01

Time series regression has been developed and long used to evaluate the short-term associations of air pollution and weather with mortality or morbidity of non-infectious diseases. The application of the regression approaches from this tradition to infectious diseases, however, is less well explored and raises some new issues. We discuss and present potential solutions for five issues often arising in such analyses: changes in immune population, strong autocorrelations, a wide range of plausible lag structures and association patterns, seasonality adjustments, and large overdispersion. The potential approaches are illustrated with datasets of cholera cases and rainfall from Bangladesh and influenza and temperature in Tokyo. Though this article focuses on the application of the traditional time series regression to infectious diseases and weather factors, we also briefly introduce alternative approaches, including mathematical modeling, wavelet analysis, and autoregressive integrated moving average (ARIMA) models. Modifications proposed to standard time series regression practice include using sums of past cases as proxies for the immune population, and using the logarithm of lagged disease counts to control autocorrelation due to true contagion, both of which are motivated from "susceptible-infectious-recovered" (SIR) models. The complexity of lag structures and association patterns can often be informed by biological mechanisms and explored by using distributed lag non-linear models. For overdispersed models, alternative distribution models such as quasi-Poisson and negative binomial should be considered. Time series regression can be used to investigate dependence of infectious diseases on weather, but may need modifying to allow for features specific to this context. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Personality and Physical Correlates of Bulimic Symptomatology among Mexican American Female College Students.

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Lester, Regan; Petrie, Trent A.

1995-01-01

Examined the relationship of personality and physical variables to bulimic symptoms. Hierarchical regression analysis of a sample of Mexican American female students revealed that body mass and endorsement of United States societal values concerning attractiveness were related positively to bulimic symptomatology; age, body satisfaction, and…

Building a new predictor for multiple linear regression technique-based corrective maintenance turnaround time.

Science.gov (United States)

Cruz, Antonio M; Barr, Cameron; Puñales-Pozo, Elsa

2008-01-01

This research's main goals were to build a predictor for a turnaround time (TAT) indicator for estimating its values and use a numerical clustering technique for finding possible causes of undesirable TAT values. The following stages were used: domain understanding, data characterisation and sample reduction and insight characterisation. Building the TAT indicator multiple linear regression predictor and clustering techniques were used for improving corrective maintenance task efficiency in a clinical engineering department (CED). The indicator being studied was turnaround time (TAT). Multiple linear regression was used for building a predictive TAT value model. The variables contributing to such model were clinical engineering department response time (CE(rt), 0.415 positive coefficient), stock service response time (Stock(rt), 0.734 positive coefficient), priority level (0.21 positive coefficient) and service time (0.06 positive coefficient). The regression process showed heavy reliance on Stock(rt), CE(rt) and priority, in that order. Clustering techniques revealed the main causes of high TAT values. This examination has provided a means for analysing current technical service quality and effectiveness. In doing so, it has demonstrated a process for identifying areas and methods of improvement and a model against which to analyse these methods' effectiveness.

A classical regression framework for mediation analysis: fitting one model to estimate mediation effects.

Science.gov (United States)

Saunders, Christina T; Blume, Jeffrey D

2017-10-26

Mediation analysis explores the degree to which an exposure's effect on an outcome is diverted through a mediating variable. We describe a classical regression framework for conducting mediation analyses in which estimates of causal mediation effects and their variance are obtained from the fit of a single regression model. The vector of changes in exposure pathway coefficients, which we named the essential mediation components (EMCs), is used to estimate standard causal mediation effects. Because these effects are often simple functions of the EMCs, an analytical expression for their model-based variance follows directly. Given this formula, it is instructive to revisit the performance of routinely used variance approximations (e.g., delta method and resampling methods). Requiring the fit of only one model reduces the computation time required for complex mediation analyses and permits the use of a rich suite of regression tools that are not easily implemented on a system of three equations, as would be required in the Baron-Kenny framework. Using data from the BRAIN-ICU study, we provide examples to illustrate the advantages of this framework and compare it with the existing approaches. © The Author 2017. Published by Oxford University Press.

Effective behaviour change techniques for physical activity and healthy eating in overweight and obese adults; systematic review and meta-regression analyses.

Science.gov (United States)

Samdal, Gro Beate; Eide, Geir Egil; Barth, Tom; Williams, Geoffrey; Meland, Eivind

2017-03-28

This systematic review aims to explain the heterogeneity in results of interventions to promote physical activity and healthy eating for overweight and obese adults, by exploring the differential effects of behaviour change techniques (BCTs) and other intervention characteristics. The inclusion criteria specified RCTs with ≥ 12 weeks' duration, from January 2007 to October 2014, for adults (mean age ≥ 40 years, mean BMI ≥ 30). Primary outcomes were measures of healthy diet or physical activity. Two reviewers rated study quality, coded the BCTs, and collected outcome results at short (≤6 months) and long term (≥12 months). Meta-analyses and meta-regressions were used to estimate effect sizes (ES), heterogeneity indices (I 2 ) and regression coefficients. We included 48 studies containing a total of 82 outcome reports. The 32 long term reports had an overall ES = 0.24 with 95% confidence interval (CI): 0.15 to 0.33 and I 2  = 59.4%. The 50 short term reports had an ES = 0.37 with 95% CI: 0.26 to 0.48, and I 2  = 71.3%. The number of BCTs unique to the intervention group, and the BCTs goal setting and self-monitoring of behaviour predicted the effect at short and long term. The total number of BCTs in both intervention arms and using the BCTs goal setting of outcome, feedback on outcome of behaviour, implementing graded tasks, and adding objects to the environment, e.g. using a step counter, significantly predicted the effect at long term. Setting a goal for change; and the presence of reporting bias independently explained 58.8% of inter-study variation at short term. Autonomy supportive and person-centred methods as in Motivational Interviewing, the BCTs goal setting of behaviour, and receiving feedback on the outcome of behaviour, explained all of the between study variations in effects at long term. There are similarities, but also differences in effective BCTs promoting change in healthy eating and physical activity and

Dental age assessment of young Iranian adults using third molars: A multivariate regression study.

Science.gov (United States)

Bagherpour, Ali; Anbiaee, Najmeh; Partovi, Parnia; Golestani, Shayan; Afzalinasab, Shakiba

2012-10-01

In recent years, a noticeable increase in forensic age estimations of living individuals has been observed. Radiologic assessment of the mineralisation stage of third molars is of particular importance, with regard to the relevant age group. To attain a referral database and regression equations for dental age estimation of unaccompanied minors in an Iranian population was the goal of this study. Moreover, determination was made concerning the probability of an individual being over the age of 18 in case of full third molar(s) development. Using the scoring system of Gleiser and Hunt, modified by Köhler, an investigation of a cross-sectional sample of 1274 orthopantomograms of 885 females and 389 males aged between 15 and 22 years was carried out. Using kappa statistics, intra-observer reliability was tested. With Spearman correlation coefficient, correlation between the scores of all four wisdom teeth, was evaluated. We also carried out the Wilcoxon signed-rank test on asymmetry and calculated the regression formulae. A strong intra-observer agreement was displayed by the kappa value. No significant difference (p-value for upper and lower jaws were 0.07 and 0.59, respectively) was discovered by Wilcoxon signed-rank test for left and right asymmetry. The developmental stage of upper right and upper left third molars yielded the greatest correlation coefficient. The probability of an individual being over the age of 18 is 95.6% for males and 100.0% for females in case four fully developed third molars are present. Taking into consideration gender, location and number of wisdom teeth, regression formulae were arrived at. Use of population-specific standards is recommended as a means of improving the accuracy of forensic age estimates based on third molars mineralisation. To obtain more exact regression formulae, wider age range studies are recommended. Copyright © 2012 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

Mutation in filamin A causes periventricular heterotopia, developmental regression, and West syndrome in males.

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Masruha, Marcelo R; Caboclo, Luis O S F; Carrete, Henrique; Cendes, Iscia L; Rodrigues, Murilo G; Garzon, Eliana; Yacubian, Elza M T; Sakamoto, Américo C; Sheen, Volney; Harney, Megan; Neal, Jason; Hill, R Sean; Bodell, Adria; Walsh, Christopher; Vilanova, Luiz C P

2006-01-01

Familial periventricular heterotopia (PH) represents a disorder of neuronal migration resulting in multiple gray-matter nodules along the lateral ventricular walls. Prior studies have shown that mutations in the filamin A (FLNA) gene can cause PH through an X-linked dominant pattern. Heterozygotic female patients usually remain asymptomatic until the second or third decade of life, when they may have predominantly focal seizures, whereas hemizygotic male fetuses typically die in utero. Recent studies have also reported mutations in FLNA in male patients with PH who are cognitively normal. We describe PH in three male siblings with PH due to FLNA, severe developmental regression, and West syndrome. The study includes the three affected brothers and their parents. Video-EEG recordings and magnetic resonance image (MRI) scanning were performed on all individuals. Mutations for FLNA were detected by using polymerase chain reaction (PCR) on genomic DNA followed by single-stranded conformational polymorphism (SSCP) analysis or sequencing. Two of the siblings are monozygotic twins, and all had West syndrome with hypsarrhythmia on EEG. MRI of the brain revealed periventricular nodules of cerebral gray-matter intensity, typical for PH. Mutational analyses demonstrated a cytosine-to-thymidine missense mutation (c. C1286T), resulting in a threonine-to-methionine amino acid substitution in exon 9 of the FLNA gene. The association between PH and West syndrome, to our knowledge, has not been previously reported. Males with PH have been known to harbor FLNA mutations, although uniformly, they either show early lethality or survive and have a normal intellect. The current studies show that FLNA mutations can cause periventricular heterotopia, developmental regression, and West syndrome in male patients, suggesting that this type of FLNA mutation may contribute to severe neurologic deficits.

Introduction to regression graphics

CERN Document Server

Cook, R Dennis

2009-01-01

Covers the use of dynamic and interactive computer graphics in linear regression analysis, focusing on analytical graphics. Features new techniques like plot rotation. The authors have composed their own regression code, using Xlisp-Stat language called R-code, which is a nearly complete system for linear regression analysis and can be utilized as the main computer program in a linear regression course. The accompanying disks, for both Macintosh and Windows computers, contain the R-code and Xlisp-Stat. An Instructor's Manual presenting detailed solutions to all the problems in the book is ava

Multicollinearity in spatial genetics: separating the wheat from the chaff using commonality analyses.

Science.gov (United States)

Prunier, J G; Colyn, M; Legendre, X; Nimon, K F; Flamand, M C

2015-01-01

Direct gradient analyses in spatial genetics provide unique opportunities to describe the inherent complexity of genetic variation in wildlife species and are the object of many methodological developments. However, multicollinearity among explanatory variables is a systemic issue in multivariate regression analyses and is likely to cause serious difficulties in properly interpreting results of direct gradient analyses, with the risk of erroneous conclusions, misdirected research and inefficient or counterproductive conservation measures. Using simulated data sets along with linear and logistic regressions on distance matrices, we illustrate how commonality analysis (CA), a detailed variance-partitioning procedure that was recently introduced in the field of ecology, can be used to deal with nonindependence among spatial predictors. By decomposing model fit indices into unique and common (or shared) variance components, CA allows identifying the location and magnitude of multicollinearity, revealing spurious correlations and thus thoroughly improving the interpretation of multivariate regressions. Despite a few inherent limitations, especially in the case of resistance model optimization, this review highlights the great potential of CA to account for complex multicollinearity patterns in spatial genetics and identifies future applications and lines of research. We strongly urge spatial geneticists to systematically investigate commonalities when performing direct gradient analyses. © 2014 John Wiley & Sons Ltd.

Estimation of Stature from Footprint Anthropometry Using Regression Analysis: A Study on the Bidayuh Population of East Malaysia

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T. Nataraja Moorthy

2015-05-01

Full Text Available The human foot has been studied for a variety of reasons, i.e., for forensic as well as non-forensic purposes by anatomists, forensic scientists, anthropologists, physicians, podiatrists, and numerous other groups. An aspect of human identification that has received scant attention from forensic anthropologists is the study of human feet and the footprints made by the feet. The present study, conducted during 2013-2014, aimed to derive population specific regression equations to estimate stature from the footprint anthropometry of indigenous adult Bidayuhs in the east of Malaysia. The study sample consisted of 480 bilateral footprints collected using a footprint kit from 240 Bidayuhs (120 males and 120 females, who consented to taking part in the study. Their ages ranged from 18 to 70 years. Stature was measured using a portable body meter device (SECA model 206. The data were analyzed using PASW Statistics version 20. In this investigation, better results were obtained in terms of correlation coefficient (R between stature and various footprint measurements and regression analysis in estimating the stature. The (R values showed a positive and statistically significant (p < 0.001 relationship between the two parameters. The correlation coefficients in the pooled sample (0.861–0.882 were comparatively higher than those of an individual male (0.762-0.795 and female (0.722-0.765. This study provided regression equations to estimate stature from footprints in the Bidayuh population. The result showed that the regression equations without sex indicators performed significantly better than models with gender indications. The regression equations derived for a pooled sample can be used to estimate stature, even when the sex of the footprint is unknown, as in real crime scenes.

Regression analysis of growth responses to water depth in three wetland plant species

DEFF Research Database (Denmark)

Sorrell, Brian K; Tanner, Chris C; Brix, Hans

2012-01-01

depths from 0 – 0.5 m. Morphological and growth responses to depth were followed for 54 days before harvest, and then analysed by repeated measures analysis of covariance, and non-linear and quantile regression analysis (QRA), to compare flooding tolerances. Principal results Growth responses to depth...

Time-trend of melanoma screening practice by primary care physicians: A meta-regression analysis

OpenAIRE

Valachis, Antonis; Mauri, Davide; Karampoiki, Vassiliki; Polyzos, Nikolaos P; Cortinovis, Ivan; Koukourakis, Georgios; Zacharias, Georgios; Xilomenos, Apostolos; Tsappi, Maria; Casazza, Giovanni

2009-01-01

Objective To assess whether the proportion of primary care physicians implementing full body skin examination (FBSE) to screen for melanoma changed over time. Methods Meta-regression analyses of available data. Data Sources: MEDLINE, ISI, Cochrane Central Register of Controlled Trials. Results Fifteen studies surveying 10,336 physicians were included in the analyses. Overall, 15%?82% of them reported to perform FBSE to screen for melanoma. The proportion of physicians using FBSE screening ten...

Motivation Factors for Female Entrepreneurship in Mexico

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Martha Cantú Cavada

2017-09-01

Full Text Available Objective: The objective of this paper is to analyse motivation factors for female entrepreneurship in Mexico. In the proposed article, the authors discuss the factors which compelled women to start their enterprises in Mexico. Research Design & Methods: Based on in-depth interviews with female entrepreneurs and entrepreneurship experts, the authors show which factors motivated women to start their own business in Mexico. Findings: The study proves that women in Mexico are motivated by a combination of push and pull factors, where the majority of the factors are pull factors. The findings of the study help to conclude that female entrepreneurship development is influenced by different factors including the entrepreneurs’ personal traits, social and economic factors. Due to their conservative traditional attitude, risk adverse tendency, and non-cooperation of family members, etc. women entrepreneurs are sometimes deterred to start a business in Mexico. Implications & Recommendations: It is necessary to raise the awareness of different factors that promote female entrepreneurship in Mexico. Governmental programmes which support female entrepreneurship, business incubators, and networking could be very helpful for women when starting their own business. Contribution & Value Added: The originality of this work lies in studying motivational factors for female entrepreneurship in Mexico. The Mexican society faces a big revolution towards female entrepreneurship. Based on the change of family structure and traditions, women nowadays are having more opportunities to develop as entrepreneurs.

A longitudinal investigation of the mediating role of self-esteem and body importance in the relationship between stress and body dissatisfaction in adolescent females and males.

Science.gov (United States)

Murray, Kristen; Rieger, Elizabeth; Byrne, Don

2013-09-01

Body dissatisfaction is particularly prevalent during adolescence and has recently been linked to stress in females and males. However, prospective studies are needed to better understand the relationship between stress and body dissatisfaction. The present study investigates the direction of this association and the mediating role of self-esteem and body image importance. A sample of 298 adolescent females and males in Grades 7 to 10 (ages 12 to 17 years) were surveyed at two time points over a one-year period. Hierarchical regression analyses revealed that stress significantly predicted body dissatisfaction one year later. Furthermore, a multiple mediation analysis controlling for gender revealed a significant indirect effect in both cross-sectional and longitudinal models, indicating that stress predicts reductions in self-esteem and increases in body importance, which in turn predict body dissatisfaction. These findings suggest that stress, self-esteem, and body importance should be included in programmes aimed at improving body dissatisfaction. Copyright © 2013 Elsevier Ltd. All rights reserved.

The impact of discrimination on the mental health of trans*female youth and the protective effect of parental support

OpenAIRE

Wilson, Erin C.; Chen, Yea-Hung; Arayasirikul, Sean; Raymond, H. Fisher; McFarland, Willi

2016-01-01

Significant health disparities exist for transgender female (trans*female) youth. We assessed differences in mental health outcomes based on exposure to discrimination among transgender female youth in the San Francisco Bay Area aged 16–24 years. Youth were recruited using a combination of respondent driven sampling with online and social media methods. Logistic regression models were used to estimate odds ratios for the mental health outcomes, comparing levels of discrimination and levels of...

A structural comparison of female-male and female-female mounting in Japanese macaques (Macaca fuscata).

Science.gov (United States)

Ottenheimer Carrier, Lydia; Leca, Jean-Baptiste; Pellis, Sergio; Vasey, Paul L

2015-10-01

In certain populations, female Japanese macaques (Macaca fuscata) mount both males and females. Vasey (2007) proposed that female-female sexual mounting in Japanese macaques may be a neutral evolutionary by-product of a purported adaptation, namely, female-male mounting. In this study, we aim to further examine the proposed link between female-male and female-female mounting in Japanese macaques by comparing the structural characteristics that define both forms of mounting. We do so using Eshkol-Wachman Movement Notation (EWMN), a globographic reference system that can be used to describe the position of body segments. No significant differences were observed in the female mounters' positioning of eight different body segments (i.e., lower torso, mid-torso, upper torso, upper arm, lower arm, upper leg, lower leg, and foot) during female-male and female-female mounting. This finding lends support to the conclusion that female-female and female-male mounting are structurally, and thus, evolutionarily, related. Copyright © 2015 Elsevier B.V. All rights reserved.

Overweight perception: associations with weight control goals, attempts and practices among Chinese female college students

Science.gov (United States)

Tanenbaum, Hilary C.; Felicitas, Jamie Q.; Li, Yawen; Tobias, Malaika; Chou, Chih-Ping; Palmer, Paula H.; Spruijt-Metz, Donna; Reynolds, Kim D.; Johnson, C. Anderson; Xie, Bin

2015-01-01

Background Concurrent with the dramatic cultural and economic shifts occurring as Mainland China becomes increasingly “Westernized,” the weight perceptions, ideal body weight, and weight management goals and practices of Chinese females have also undergone significant changes. Objective To investigate relationships between overweight status, weight perception patterns, and weight management goals and practices in Chinese female college students. Design/Participants/Setting A cross-sectional analysis was conducted with data from 902 female subjects aged 18 to 25 years participating in the China Seven Cities Study, a health promotion and smoking prevention study conducted in Mainland China in 2003. Main Outcome Measures/ Statistical Analyses Logistic regression models were used to explore associations between overweight status, weight perception, specific weight management goals and practices, and current levels of vigorous-intensity physical activity and food consumption. Results Based on World Health Organization standards for Asian adults, 16.7% of college females were overweight or obese, although 50.8% considered themselves to be “too heavy.” Among participants perceiving themselves as overweight (n=458), 69.2% (n=371) were inaccurate, and did not meet criteria for overweight or obese. The percentage of participants attempting weight loss was 48.2%, and 33.1% wanted to maintain their current weight. Attempts to lose or maintain weight were related to actual and perceived weight status, but not to increased vigorous-intensity physical activity or fruit and vegetable intake, nor to decreased consumption of sweets, soda, Western fast foods and fried foods. Only 21.5% of participants desiring weight loss or maintenance reported using a combination of vigorous-intensity physical activity and a reduced fat and calorie diet, while 20.2% tried extreme methods such as fasting, using diet pills, vomiting, or smoking. Conclusions Our findings underscore the need to

Stressed and Losing Sleep: Sleep Duration and Perceived Stress among Affluent Adolescent Females

Science.gov (United States)

DeSilva Mousseau, Angela M.; Lund, Terese J.; Liang, Belle; Spencer, Renée; Walsh, Jill

2016-01-01

This study examined the relationship between stress and sleep duration for adolescent females from affluent backgrounds. Participants were 218 students attending two independent single-sex secondary schools. Ordinary Least Squares (OLS) regression models (cross-sectional and longitudinal) were run to examine the association between stress and…

Frequency of different blood groups and its association with BMI and blood pressure among the female medical students of Faisalabad.

Science.gov (United States)

Jawed, Shireen; Zia, Sadaf; Tariq, Sundus

2017-08-01

To determine the frequency of different blood groups among female medical students and to find the association of blood groups and body mass index with blood pressure. This cross-sectional study was performed at the University Medical and Dental College, Faisalabad, Pakistan, from March to April 2016, and comprised female medical students. Participants were divided into groups on the basis of their ABO blood groups and on body mass index criteria. Blood groups were determined by simple conventional slide method. Blood pressure was estimated by manual auscultatory technique with a mercury sphygmomanometer. Data was analysed usingSPSS20. There were 145 students with an overall mean age of18.4±0.75 years (range: 17-23 years). Blood group B was the predominant group 65(44.8%). Besides, 130(89.6%) subjects were rhesus positive and 23(53%) subjects of blood group O were pre-hypertensive. Multiple regression analysis indicated significant positive association of blood group O with both systolic and diastolic blood pressure (p=0.002, 0.001). However, subsequent logistic regression showed significant association only with diastolic blood pressure (p=0.001). Relative risk of pre-hypertension for obese (p=0.001) was greater than non-obese subjects. Body mass index was significantly associated with both systolic and diastolic blood pressure (p=0.004, 0.042). Blood group B was the most common blood group. Blood group O was associated with diastolic pre-hypertension, while body mass index was associated with both systolic and diastolic pre-hypertension.

Male depression in females?

Science.gov (United States)

Möller-Leimkühler, Anne Maria; Yücel, Mete

2010-02-01

Scientific evidence for a male-typed depression ("male depression") is still limited, but mainly supports this concept with respect to single externalizing symptoms or symptom clusters. In particular, studies on non-clinical populations including males and females are lacking. The present study aims at assessing general well-being, the risk and the symptoms of male depression dependent on biological sex and gender-role orientation on instrumental (masculine) and expressive (feminine) personality traits in an unselected community sample of males and females. Students (518 males, 500 females) of the Ludwig-Maximilians-University of Munich, Germany, were asked to participate in a "stress study" and complete the following self-report questionnaires: the WHO-5 Well-being Index [Bech, P., 1998. Quality of Life in the Psychiatric Patient. Mosby-Wolfe, London], the Gotland Scale for Male Depression [Walinder, J., Rutz, W., 2001. Male depression and suicide. International Clinical Psychopharmacology 16 (suppl 2), 21-24] and the German Extended Personal Attribute Questionnaire [Runge, T.E., Frey, D., Gollwitzer, P.M., et al., 1981. Masculine (instrumental) and feminine (expressive) traits. A comparison between students in the United States and West Germany. Journal of Cross-Cultural Psychology 12, 142-162]. General well-being of the students was significantly lower compared to population norms. Contrary to expectations, female students had a greater risk of male depression than male students (28.9% vs. 22.4%; p<0.05). Overall, prototypic depressive symptoms as well as externalizing symptoms were more pronounced in females. In the subgroup of those at risk for male depression, biological sex and kind of symptoms were unrelated. Principal component analyses revealed a similar symptom structure for males and females. Low scores on masculinity/instrumentality significantly predicted higher risk of male depression, independent of biological sex. The study sample is not

Coevolution of female and male genital components to avoid genital size mismatches in sexually dimorphic spiders.

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Lupše, Nik; Cheng, Ren-Chung; Kuntner, Matjaž

2016-08-17

In most animal groups, it is unclear how body size variation relates to genital size differences between the sexes. While most morphological features tend to scale with total somatic size, this does not necessarily hold for genitalia because divergent evolution in somatic size between the sexes would cause genital size mismatches. Theory predicts that the interplay of female-biased sexual size dimorphism (SSD) and sexual genital size dimorphism (SGD) should adhere to the 'positive genital divergence', the 'constant genital divergence', or the 'negative genital divergence' model, but these models remain largely untested. We test their validity in the spider family Nephilidae known for the highest degrees of SSD among terrestrial animals. Through comparative analyses of sex-specific somatic and genital sizes, we first demonstrate that 99 of the 351 pairs of traits are phylogenetically correlated. Through factor analyses we then group these traits for MCMCglmm analyses that test broader correlation patterns, and these reveal significant correlations in 10 out of the 36 pairwise comparisons. Both types of analyses agree that female somatic and internal genital sizes evolve independently. While sizes of non-intromittent male genital parts coevolve with male body size, the size of the intromittent male genital parts is independent of the male somatic size. Instead, male intromittent genital size coevolves with female (external and, in part, internal) genital size. All analyses also agree that SGD and SSD evolve independently. Internal dimensions of female genitalia evolve independently of female body size in nephilid spiders, and similarly, male intromittent genital size evolves independently of the male body size. The size of the male intromittent organ (the embolus) and the sizes of female internal and external genital components thus seem to respond to selection against genital size mismatches. In accord with these interpretations, we reject the validity of the

Sex Trafficking Related Knowledge, Awareness, and Attitudes among Adolescent Female Students in Nepal: A Cross-Sectional Study.

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Roman Shrestha

Full Text Available Sex trafficking has been a long-standing concern in Nepal. Very little has been achieved, however, in terms of actual reduction in the number of victims despite numerous anti-sex trafficking programs. This situation may be attributable to a lack of empirical evidence upon which to formulate anti-sexual trafficking interventions. This study aimed to assess sex trafficking-related knowledge, awareness and attitudes, and factors associated with sex trafficking awareness and attitudes towards the victims of sex trafficking and/or anti-sex trafficking campaigns among adolescent female students in Nepal.A cross-sectional study was conducted between August-September 2013 among 292 adolescent female students (>10 years old using systematic random sampling from three high schools in Sindhupalchowk district, Nepal. As an initial step, descriptive analyses were employed to characterize the data and multivariate logistic regression analyses were used to explore factors associated with sex trafficking awareness and related attitudes.Seventy-six percent of sampled students reported that they were aware of sex trafficking and 94.6% indicated media (i.e., radio or television as the primary sources of their knowledge. Fifty-one percent mentioned relatives/friends as mediators of sex trafficking, 60.4% reported promise for better jobs as the primary attraction behind sex trafficking, and 48.6% mentioned adolescent females as the most vulnerable group for sex trafficking. Over half (56.8% of the respondents had positive attitudes towards the victims of sex trafficking and/or anti-sex trafficking campaigns. Age (OR = 3.38, 95% CI:2.51-4.55, parents' occupation (OR = 3.89, 95% CI:1.58-9.58, and having a radio/TV at home (OR = 6.67, 95% CI:3.99-9.54 were significantly associated with awareness, whereas being younger (OR = 0.67, 95% CI:0.55-0.79 and having joint-family (OR = 2.67, 95% CI:1.49-4.80 were significantly associated with having a positive attitudes towards

Multivariate differential analyses of adolescents' experiences of aggression in families

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Chris Myburgh

2011-01-01

Full Text Available Aggression is part of South African society and has implications for the mental health of persons living in South Africa. If parents are aggressive adolescents are also likely to be aggressive and that will impact negatively on their mental health. In this article the nature and extent of adolescents' experiences of aggression and aggressive behaviour in the family are investigated. A deductive explorative quantitative approach was followed. Aggression is reasoned to be dependent on aspects such as self-concept, moral reasoning, communication, frustration tolerance and family relationships. To analyse the data from questionnaires of 101 families (95 adolescents, 95 mothers and 91 fathers Cronbach Alpha, various consecutive first and second order factor analyses, correlations, multiple regression, MANOVA, ANOVA and Scheffè/ Dunnett tests were used. It was found that aggression correlated negatively with the independent variables; and the correlations between adolescents and their parents were significant. Regression analyses indicated that different predictors predicted aggression. Furthermore, differences between adolescents and their parents indicated that the experienced levels of aggression between adolescents and their parents were small. Implications for education are given.

Association Between Cumulative Psychosocial Risk and Cervical Human Papillomavirus Infection Among Female Adolescents in a Free Vaccination Program.

Science.gov (United States)

Linares, Lourdes Oriana; Shankar, Viswanathan; Diaz, Angela; Nucci-Sack, Anne; Strickler, Howard D; Peake, Ken; Weiss, Jocelyn; Burk, Robert D; Schlecht, Nicolas F

2015-10-01

This study investigated the association of cervical human papillomavirus (HPV) infection with cumulative psychosocial risk reflecting family disadvantage, psychological distress, and unhealthy lifestyle. The sample (N = 745) comprised sexually active female adolescent patients (12-19 yr), primarily ethnic minorities, enrolled in a free HPV vaccination program. Subjects completed questionnaires and provided cervical swabs for HPV DNA testing. Unweighted and weighted principal component analyses for categorical data were used to derive multisystemic psychosocial risk indices using 9 indicators: low socioeconomic status, lack of adult involvement, not attending high school/college, history of treatment for depression/anxiety, antisocial/delinquent behavior, number of recent sexual partners, use of alcohol, use of drugs, and dependency risk for alcohol/drugs. The association between cervical HPV (any type, high-risk types, vaccine types) assayed by polymerase chain reaction and self-reported number of psychosocial risk indicators was estimated using multivariable logistic regression. Subjects had a median of 3 psychosocial risk indicators. Multiple logistic regression analyses showed associations with unweighted and weighted number of psychosocial indicators for HPV any type (adjusted odds ratio [aOR] = 1.1; 95% confidence interval [CI], 1.0-1.2), with the strongest associations between weighted drug/alcohol use, drug/alcohol dependency risk, and antisocial/delinquent behavior and detection of HPV vaccine types (aOR = 1.5; 95% CI, 1.1-2.0) independent of number of recent sexual partners and vaccine dose (0-3). Increased HPV infections including HPV vaccine types were associated with greater number of psychosocial risk indicators even after controlling for demographics, sexual behavior, history of chlamydia, and vaccine dose.

Availability and Price of High Quality Day Care and Female Employment

DEFF Research Database (Denmark)

Simonsen, Marianne

In this paper I analyse to what degree availability and price of high quality publicly subsidised childcare affects female employment for women living in couples following maternity leave. The results show that unrestricted access to day care has a significantly positive effct on female employment.......The price effect is significantly negative: An increase in the price of child care of C=1 will decrease the female employment with 0.08% corresponding to a price elasticity of −0.17. This effect prevails during the first 12 months after childbirth....

The impact of psychological stress on men's judgements of female body size.

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Swami, Viren; Tovée, Martin J

2012-01-01

Previous work has suggested that the experience of psychological stress may influence physical attractiveness ideals, but most evidence in favour of this hypothesis remains archival. The objective of this study was to experimentally investigate the impact of stress on men's judgements of female body size. Men were randomly assigned to either an experimental group, in which they took part in a task that heightened stress (experimental group, n = 41) or in which they did not take part in such a task (control group, n = 40). Both groups rated the attractiveness of female bodies varying in size from emaciated to obese, completed a measure of appetite sensation, and had their body mass indices (BMIs) measured. Between-groups analyses showed that the experimental group was matched with the control group in terms of mean age, BMI, and appetite sensation. Further analyses showed that men in the experimental group rated a significantly heavier female body size as maximally attractive than the control group. Men in the experimental group also rated heavier female bodies as more attractive and idealised a wider range of female figures than did the control group. This study found that the experience of stress was associated with a preference among men for heavier female body sizes. These results indicate that human attractiveness judgements are sensitive to variations in local ecologies and reflect adaptive strategies for dealing with changing environmental conditions.

Animal models of maternal high fat diet exposure and effects on metabolism in offspring: a meta-regression analysis.

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Ribaroff, G A; Wastnedge, E; Drake, A J; Sharpe, R M; Chambers, T J G

2017-06-01

Animal models of maternal high fat diet (HFD) demonstrate perturbed offspring metabolism although the effects differ markedly between models. We assessed studies investigating metabolic parameters in the offspring of HFD fed mothers to identify factors explaining these inter-study differences. A total of 171 papers were identified, which provided data from 6047 offspring. Data were extracted regarding body weight, adiposity, glucose homeostasis and lipidaemia. Information regarding the macronutrient content of diet, species, time point of exposure and gestational weight gain were collected and utilized in meta-regression models to explore predictive factors. Publication bias was assessed using Egger's regression test. Maternal HFD exposure did not affect offspring birthweight but increased weaning weight, final bodyweight, adiposity, triglyceridaemia, cholesterolaemia and insulinaemia in both female and male offspring. Hyperglycaemia was found in female offspring only. Meta-regression analysis identified lactational HFD exposure as a key moderator. The fat content of the diet did not correlate with any outcomes. There was evidence of significant publication bias for all outcomes except birthweight. Maternal HFD exposure was associated with perturbed metabolism in offspring but between studies was not accounted for by dietary constituents, species, strain or maternal gestational weight gain. Specific weaknesses in experimental design predispose many of the results to bias. © 2017 The Authors. Obesity Reviews published by John Wiley & Sons Ltd on behalf of World Obesity Federation.

Preference learning with evolutionary Multivariate Adaptive Regression Spline model

DEFF Research Database (Denmark)

Abou-Zleikha, Mohamed; Shaker, Noor; Christensen, Mads Græsbøll

2015-01-01

This paper introduces a novel approach for pairwise preference learning through combining an evolutionary method with Multivariate Adaptive Regression Spline (MARS). Collecting users' feedback through pairwise preferences is recommended over other ranking approaches as this method is more appealing...... for function approximation as well as being relatively easy to interpret. MARS models are evolved based on their efficiency in learning pairwise data. The method is tested on two datasets that collectively provide pairwise preference data of five cognitive states expressed by users. The method is analysed...

Electrocortical Reactivity During Self-referential Processing in Female Youth With Borderline Personality Disorder.

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Auerbach, Randy P; Tarlow, Naomi; Bondy, Erin; Stewart, Jeremy G; Aguirre, Blaise; Kaplan, Cynthia; Yang, Wenhui; Pizzagalli, Diego A

2016-07-01

Borderline personality disorder (BPD) is debilitating, and theoretical models have postulated that cognitive-affective biases contribute to the onset and maintenance of BPD symptoms. Despite advances, our understanding of BPD pathophysiology in youth is limited. The present study used event-related potentials (ERPs) to identify cognitive-affective processes that underlie negative self-referential processing in BPD youth. Healthy females ( n = 33) and females with BPD ( n = 26) 13 to 22 years of age completed a self-referential encoding task while 128-channel electroencephalography data were recorded to examine early (i.e., P1 and P2) and late (late positive potential [LPP]) ERP components. Whole-brain standardized low-resolution electromagnetic tomography explored intracortical sources underlying significant scalp ERP effects. Compared to healthy females, participants with BPD endorsed, recalled, and recognized fewer positive and more negative words. Moreover, unlike the healthy group, females with BPD had faster reaction times to endorse negative versus positive words. In the scalp ERP analyses, the BPD group had greater P2 and late LPP positivity to negative as opposed to positive words. For P2 and late LPP, whole-brain standardized low-resolution electromagnetic tomography analyses suggested that females with BPD overrecruit frontolimbic circuitry in response to negative stimuli. Collectively, these findings show that females with BPD process negative self-relevant information differently than healthy females. Clinical implications and future directions are discussed.

A random regression model in analysis of litter size in pigs | Lukovi& ...

African Journals Online (AJOL)

Dispersion parameters for number of piglets born alive (NBA) were estimated using a random regression model (RRM). Two data sets of litter records from the Nemščak farm in Slovenia were used for analyses. The first dataset (DS1) included records from the first to the sixth parity. The second dataset (DS2) was extended ...

Prediction of unwanted pregnancies using logistic regression, probit regression and discriminant analysis.

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Ebrahimzadeh, Farzad; Hajizadeh, Ebrahim; Vahabi, Nasim; Almasian, Mohammad; Bakhteyar, Katayoon

2015-01-01

Unwanted pregnancy not intended by at least one of the parents has undesirable consequences for the family and the society. In the present study, three classification models were used and compared to predict unwanted pregnancies in an urban population. In this cross-sectional study, 887 pregnant mothers referring to health centers in Khorramabad, Iran, in 2012 were selected by the stratified and cluster sampling; relevant variables were measured and for prediction of unwanted pregnancy, logistic regression, discriminant analysis, and probit regression models and SPSS software version 21 were used. To compare these models, indicators such as sensitivity, specificity, the area under the ROC curve, and the percentage of correct predictions were used. The prevalence of unwanted pregnancies was 25.3%. The logistic and probit regression models indicated that parity and pregnancy spacing, contraceptive methods, household income and number of living male children were related to unwanted pregnancy. The performance of the models based on the area under the ROC curve was 0.735, 0.733, and 0.680 for logistic regression, probit regression, and linear discriminant analysis, respectively. Given the relatively high prevalence of unwanted pregnancies in Khorramabad, it seems necessary to revise family planning programs. Despite the similar accuracy of the models, if the researcher is interested in the interpretability of the results, the use of the logistic regression model is recommended.

A meta-analysis of the association between induced abortion and breast cancer risk among Chinese females.

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Huang, Yubei; Zhang, Xiaoliang; Li, Weiqin; Song, Fengju; Dai, Hongji; Wang, Jing; Gao, Ying; Liu, Xueou; Chen, Chuan; Yan, Ye; Wang, Yaogang; Chen, Kexin

2014-02-01

To evaluate the association between induced abortion (IA) and breast cancer risk among Chinese females. We searched three English databases (PubMed, ScienceDirect, and Wiley) and three Chinese databases (CNKI, WanFang, and VIP) for studies up to December 2012, supplemented by manual searches. Two reviewers independently conducted the literature searching, study selection, and data extraction and quality assessment of included studies. Random effects models were used to estimate the summary odds ratios (ORs) and the 95 % confidence intervals (CIs). A total of 36 articles (two cohort studies and 34 case-control studies) covering 14 provinces in China were included in this review. Compared to people without any history of IA, an increased risk of breast cancer was observed among females who had at least one IA (OR = 1.44, 95 % CI 1.29-1.59, I (2) = 82.6 %, p 40-2.55) for people who had at least two IAs and at least three IAs, respectively. Subgroup analyses showed similar results to the primary results. Meta-regression analysis of the included studies found that the association between IA and breast cancer risk attenuated with increasing percent of IA in the control group (β = -0.022, p IA is significantly associated with an increased risk of breast cancer among Chinese females, and the risk of breast cancer increases as the number of IA increases. If IA were to be confirmed as a risk factor for breast cancer, high rates of IA in China may contribute to increasing breast cancer rates.

Low back pain among female nurses in Yemen

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Khaled Ghilan

2013-08-01

Full Text Available Objectives: This study aimed to investigate the prevalence of Low Back Pain (LBP among female nursing staff and explore the potential risk factors associated with LBP. Methods: An analytical cross-sectional study was conducted on randomly selected female nurses using payroll as a sampling frame in all public hospitals in Sana'a City, Yemen. Data was collected through face-to-face interview using a structured, pre-coded questionnaire that was available in Arabic and English. Weight and height of the nurses were measured using weight and height scales and body mass index was calculated. Multiple logistic regression was used to identify the factors associated with LBP. Results: Out of 696 female nurses selected, 687 (98.7% responded. The life-time, the 12-month and one-week prevalence rates of LBP among female nurses were 512 (74.5%; 95% CI: 71.1-77.7%, 411 (59.8%; 95% CI: 56.0-63.5% and 249 (36.2%; 95% CI: 32.6-39.9%, respectively. The prevalence was significantly lower in Indian nurses compared to other nurses. Three out of every 10 nurses with LBP had sick leave because of LBP in the last 12 months. Factors that showed significant association with LBP among nursing staff in the multivariate analysis were age, nationality, menstrual disorders and stress level at work. Conclusion: LBP is common among female nurses in Yemen. The role of menstrual disorders in developing LBP among female nurses seems to be important. Although sharing the same working conditions, Indian nurses were less likely to report LBP, which highlight the importance of cultural differences in willingness to report LBP.

Can sexual selection drive female life histories? A comparative study on Galliform birds.

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Kolm, N; Stein, R W; Mooers, A Ø; Verspoor, J J; Cunningham, E J A

2007-03-01

Sexual selection has been identified as a major evolutionary force shaping male life history traits but its impact on female life history evolution is less clear. Here we examine the impact of sexual selection on three key female traits (body size, egg size and clutch size) in Galliform birds. Using comparative independent contrast analyses and directional discrete analyses, based on published data and a new genera-level supertree phylogeny of Galliform birds, we investigated how sexual selection [quantified as sexual size dimorphism (SSD) and social mating system (MS)] affects these three important female traits. We found that female body mass was strongly and positively correlated with egg size but not with clutch size, and that clutch size decreased as egg size increased. We established that SSD was related to MS, and then used SSD as a proxy of the strength of sexual selection. We found both a positive relationship between SSD and female body mass and egg size and that increases in female body mass and egg size tend to occur following increases in SSD in this bird order. This pattern of female body mass increases lagging behind changes in SSD, established using our directional discrete analysis, suggests that female body mass increases as a response to increases in the level of sexual selection and not simply through a strong genetic relationship with male body mass. This suggests that sexual selection is linked to changes in female life history traits in Galliformes and we discuss how this link may shape patterns of life history variation among species.

Increasing hookah use among adolescent females in the US: analyses from the 2011-2014 National Youth Tobacco Survey (NYTS

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Jenni A. Shearston

2016-09-01

These data demonstrate the magnitude of adolescent hookah use, particularly among adolescents who use electronic or traditional cigarettes. Most strikingly, rates of female adolescent use have increased much more rapidly than has male use, and adolescent females are for the first time more likely to smoke hookahs than adolescent males in the US nationwide. These findings urgently call for better understanding of the changing correlates of hookah use, including polytobacco use.

The Relationship Between Biomechanical Indicators of the Snatch Technique and Female Weightlifters' Levels

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Szyszka Paulina

2015-03-01

Full Text Available Introduction. The snatch technique is a discipline in Olympic weightlifting. The lifter has to raise the barbell from the platform directly above their head in one movement. While reviewing the literature on biomechanical analysis of the techniques of weightlifting, one can find positions on the analysis of parameters, such as barbell track, horizontal displacement, and angular positions of the joints in the individual phases of the lifter's movement. Many texts concern female and male lifters taking part in World or European Championships. The parameters of the best competitors are outlined - mostly those who finish in the top five places in competition. Mostly these are parameters regarding male lifters, and less frequently those of female lifters. In the literature review, an overlooked aspect is that of the definition of the diversity of indicators as regards the snatch technique practiced by female lifters depending on score. Material and methods. In the research, registered snatch attempts during the World Championship were used. Videos were used by judges to establish a maximum weight limit for female lifters. The attempts were registered by two cameras and were later digitally processed by the APAS 2000 system. Barbell parameters, maximum speed, average of the bar, and the parameters of the lifter-bar collocation (horizontal displacement of barbell weights and height elevation were assessed. Results. The analysed attempts show the margin of error for measurement of the average speed of the barbell as 0.03 m/s. The difference in maximum speed of analysed attempts is 15%. The height of clearance of the first-placed female lifter's barbell was 12.7 cm, 30 cm for the last-placed. Conclusions. The sporting level of weightlifting by female lifters influences the analysed biomechanical indicators of the snatch. Those indicators, which are similar in the case of both the World Championship winner and the female lifter who came last, may be

Pursuit of STEM: Factors shaping degree completion for African American females in STEM

Science.gov (United States)

Wilkins, Ashlee N.

The primary purpose of the study was to examine secondary data from the Cooperative Institutional Research Program (CIRP) Freshman and College Senior Surveys to investigate factors shaping degree aspirations for African American female undergraduates partaking in science, technology, engineering, and mathematics (STEM) majors. Hierarchical multiple regression was used to analyze the data and identify relationships between independent variables in relation to the dependent variable. The findings of the study reveal four key variables that were predictive of degree completion for African American females in STEM. Father's education, SAT composite, highest degree planned, and self-perception were positive predictors for females; while independent variable overall sense of community among students remained a negative predictor. Lastly implications for education and recommendations for future research were discussed.

Weight Misperceptions and Racial and Ethnic Disparities in Adolescent Female Body Mass Index

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Ramona C. Krauss

2012-01-01

Full Text Available This paper investigated weight misperceptions as determinants of racial/ethnic disparities in body mass index (BMI among adolescent females using data from the National Survey of Youth 1997. Compared to their white counterparts, higher proportions of black and Hispanic adolescent females underperceived their weight status; that is, they misperceived themselves to have lower weight status compared to their clinically defined weight status. Compared to their black counterparts, higher proportions of white and Hispanic adolescent females misperceived themselves to be heavier than their clinical weight status. Oaxaca-Blinder decomposition analysis showed that accounting for weight misperceptions, in addition to individual and contextual factors, increased the total explained portion of the black-white female BMI gap from 44.7% to 54.3% but only slightly increased the total explained portion of the Hispanic-white gap from 62.8% to 63.1%. Weight misperceptions explained 13.0% of the black-white female BMI gap and 3.3% of the Hispanic-white female BMI gap. The regression estimates showed that weight underperceptions were important determinants of adolescent female BMI, particularly among black and Hispanic adolescents. Education regarding identification and interpretation of weight status may play an important role to help reduce the incidence and racial disparity of female adolescent obesity.

Pregnancy outcomes in female hairdressers.

Science.gov (United States)

Ronda, Elena; Moen, Bente E; García, Ana M; Sánchez-Paya, José; Baste, Valborg

2010-12-01

The hairdressing occupation may entail exposure to a wide range of chemical products, psychosocial and physical stress. All these factors may affect the health of a pregnant hairdresser and her offspring. Our aim was to analyse whether employment in this profession is associated with adverse reproductive effects. Female hairdressers working in the 248 hairdressing salons in Alicante (Spain), who became pregnant for the first time after 1990 were included (n = 94). The incidence of spontaneous abortions, number of children born and their birth weight and preterm delivery among hairdressers was compared with a control group of shop assistants and office workers (n = 138). Information was collected through personal interviews at their work place. A structured questionnaire was used gathering information concerning exposure variables including the use of chemical products, ventilation at the salons, work-related stress and hours of standing work. In addition, socio-demographic factors and smoking information were obtained. Crude and adjusted relative risks (RR) and 95% confidence intervals (95%CI) were calculated using logbinomial regression. Hairdressers showed a non-significant increased risk of spontaneous abortions (RR = 1.6, 95%CI 0.9-2.7). There were no differences in preterm delivery and birth weight of the children born of mothers in the two groups. Among hairdressers, the RR of spontaneous abortion among those with high perceived work-related stress was 2.4 (95%CI: 0.2-28.3) relative to those with low or normal perceived stress. A slightly increased risk of spontaneous abortion among hairdressers was found, mainly associated with perceived work-related stress. Observed results deserve further research.

Equivalence of symptom dimensions in females and males with autism.

Science.gov (United States)

Frazier, Thomas W; Hardan, Antonio Y

2017-08-01

This study investigated equivalence of autism symptom domains in males and females with autism. Symptom data were obtained from 2643 children and adolescents with autism spectrum disorder (352 females, 2291 males; age range = 4-17 years) included in the Simons Simplex Collection. Items from the Social Responsiveness Scale and Autism Diagnostic Interview-Revised were mapped to nine a priori symptom dimensions. Multi-group confirmatory factor models, including measurement equivalence and item response theory analyses, examined whether males and females showed measurement or structural differences in autism symptom constructs. Results indicated mean differences in restricted interests that were not due to measurement bias. No other symptom dimension showed evidence of measurement bias and autism symptom structure was highly similar between males and females. Future studies are needed to carefully estimate any sex differences in the content, frequency, or intensity/severity of restricted interests in females and males.

Association between response rates and survival outcomes in patients with newly diagnosed multiple myeloma. A systematic review and meta-regression analysis.

Science.gov (United States)

Mainou, Maria; Madenidou, Anastasia-Vasiliki; Liakos, Aris; Paschos, Paschalis; Karagiannis, Thomas; Bekiari, Eleni; Vlachaki, Efthymia; Wang, Zhen; Murad, Mohammad Hassan; Kumar, Shaji; Tsapas, Apostolos

2017-06-01

We performed a systematic review and meta-regression analysis of randomized control trials to investigate the association between response to initial treatment and survival outcomes in patients with newly diagnosed multiple myeloma (MM). Response outcomes included complete response (CR) and the combined outcome of CR or very good partial response (VGPR), while survival outcomes were overall survival (OS) and progression-free survival (PFS). We used random-effect meta-regression models and conducted sensitivity analyses based on definition of CR and study quality. Seventy-two trials were included in the systematic review, 63 of which contributed data in meta-regression analyses. There was no association between OS and CR in patients without autologous stem cell transplant (ASCT) (regression coefficient: .02, 95% confidence interval [CI] -0.06, 0.10), in patients undergoing ASCT (-.11, 95% CI -0.44, 0.22) and in trials comparing ASCT with non-ASCT patients (.04, 95% CI -0.29, 0.38). Similarly, OS did not correlate with the combined metric of CR or VGPR, and no association was evident between response outcomes and PFS. Sensitivity analyses yielded similar results. This meta-regression analysis suggests that there is no association between conventional response outcomes and survival in patients with newly diagnosed MM. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Becoming a Woman: The Construction of Female Subjectivities and Its Relationship with School

Science.gov (United States)

Susinos, Teresa; Calvo, Adelina; Rojas, Susana

2009-01-01

In this article we analyse the construction processes of female subjectivities by studying the self-descriptions that various young women give about their own image, their satisfactions and dissatisfactions and their project for life. A conclusion is drawn that the construction of these female identities cannot be separated from the discursive…

Application of support vector regression (SVR) for stream flow prediction on the Amazon basin

CSIR Research Space (South Africa)

Du Toit, Melise

2016-10-01

Full Text Available regression technique is used in this study to analyse historical stream flow occurrences and predict stream flow values for the Amazon basin. Up to twelve month predictions are made and the coefficient of determination and root-mean-square error are used...

Regression and regression analysis time series prediction modeling on climate data of quetta, pakistan

International Nuclear Information System (INIS)

Jafri, Y.Z.; Kamal, L.

2007-01-01

Various statistical techniques was used on five-year data from 1998-2002 of average humidity, rainfall, maximum and minimum temperatures, respectively. The relationships to regression analysis time series (RATS) were developed for determining the overall trend of these climate parameters on the basis of which forecast models can be corrected and modified. We computed the coefficient of determination as a measure of goodness of fit, to our polynomial regression analysis time series (PRATS). The correlation to multiple linear regression (MLR) and multiple linear regression analysis time series (MLRATS) were also developed for deciphering the interdependence of weather parameters. Spearman's rand correlation and Goldfeld-Quandt test were used to check the uniformity or non-uniformity of variances in our fit to polynomial regression (PR). The Breusch-Pagan test was applied to MLR and MLRATS, respectively which yielded homoscedasticity. We also employed Bartlett's test for homogeneity of variances on a five-year data of rainfall and humidity, respectively which showed that the variances in rainfall data were not homogenous while in case of humidity, were homogenous. Our results on regression and regression analysis time series show the best fit to prediction modeling on climatic data of Quetta, Pakistan. (author)

Linear regression in astronomy. I

Science.gov (United States)

Isobe, Takashi; Feigelson, Eric D.; Akritas, Michael G.; Babu, Gutti Jogesh

1990-01-01

Five methods for obtaining linear regression fits to bivariate data with unknown or insignificant measurement errors are discussed: ordinary least-squares (OLS) regression of Y on X, OLS regression of X on Y, the bisector of the two OLS lines, orthogonal regression, and 'reduced major-axis' regression. These methods have been used by various researchers in observational astronomy, most importantly in cosmic distance scale applications. Formulas for calculating the slope and intercept coefficients and their uncertainties are given for all the methods, including a new general form of the OLS variance estimates. The accuracy of the formulas was confirmed using numerical simulations. The applicability of the procedures is discussed with respect to their mathematical properties, the nature of the astronomical data under consideration, and the scientific purpose of the regression. It is found that, for problems needing symmetrical treatment of the variables, the OLS bisector performs significantly better than orthogonal or reduced major-axis regression.

Logic regression and its extensions.

Science.gov (United States)

Schwender, Holger; Ruczinski, Ingo

2010-01-01

Logic regression is an adaptive classification and regression procedure, initially developed to reveal interacting single nucleotide polymorphisms (SNPs) in genetic association studies. In general, this approach can be used in any setting with binary predictors, when the interaction of these covariates is of primary interest. Logic regression searches for Boolean (logic) combinations of binary variables that best explain the variability in the outcome variable, and thus, reveals variables and interactions that are associated with the response and/or have predictive capabilities. The logic expressions are embedded in a generalized linear regression framework, and thus, logic regression can handle a variety of outcome types, such as binary responses in case-control studies, numeric responses, and time-to-event data. In this chapter, we provide an introduction to the logic regression methodology, list some applications in public health and medicine, and summarize some of the direct extensions and modifications of logic regression that have been proposed in the literature. Copyright © 2010 Elsevier Inc. All rights reserved.

Factors associated with pre-marital sexual debut among unmarried high school female students in bahir Dar town, Ethiopia: cross- sectional study.

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Mulugeta, Yeshalem; Berhane, Yemane

2014-05-31

Pre-marital sexual debut increase the risk of sexually transmitted infections (STIs) including HIV/AIDS and unwanted pregnancy. It may also affect their school performance and completion rate. In spite of this fact, number of unmarried female students who started sexual debut is increasing from time to time. However, information on the extent of pre-marital sexual debut and associated factors were not well studied and documented in the study area where pre-marital sexual debut is largely condemned. Therefore this study was conducted to assess the magnitude and associated factors of pre-marital sexual debut. School based cross-sectional survey was conducted from May 10-13/2012. A total of 1123 unmarried high school female students were selected by multi- stage sampling technique. Data were collected using structured, self administered questionnaire. Descriptive statistics, binary and multivariable logistic regression analyses were used to identify factors associated with pre-marital sexual debut. Among unmarried high school female students 30.8% reported pre-marital sexual debut. The major associated factors were frequent watching of pornographic video [AOR = 10.15, 95% CI: (6.63, 15.53)], peer pressure [AOR = 2.98, 95% CI: (1.57, 5.67)] and chewing khat [AOR = 8.99, 95% CI: (3.84, 21.06)]. Significant proportion of unmarried high school female students have started pre-marital sexual debut. The finding suggests the need for communicating and supporting school students to help them make informed and safer decisions on their sexual behavior. Therefore, Bahir dar city administration health and education bureau should design persistent and effective health education to decrease pre-marital sexual debut in unmarried female students.

Factors associated with pre-marital sexual debut among unmarried high school female students in bahir Dar town, Ethiopia: cross- sectional study

Science.gov (United States)

2014-01-01

Background Pre-marital sexual debut increase the risk of sexually transmitted infections (STIs) including HIV/AIDS and unwanted pregnancy. It may also affect their school performance and completion rate. In spite of this fact, number of unmarried female students who started sexual debut is increasing from time to time. However, information on the extent of pre-marital sexual debut and associated factors were not well studied and documented in the study area where pre-marital sexual debut is largely condemned. Therefore this study was conducted to assess the magnitude and associated factors of pre-marital sexual debut. Methods School based cross-sectional survey was conducted from May 10-13/2012. A total of 1123 unmarried high school female students were selected by multi- stage sampling technique. Data were collected using structured, self administered questionnaire. Descriptive statistics, binary and multivariable logistic regression analyses were used to identify factors associated with pre-marital sexual debut. Results Among unmarried high school female students 30.8% reported pre-marital sexual debut. The major associated factors were frequent watching of pornographic video [AOR = 10.15, 95% CI: (6.63, 15.53)], peer pressure [AOR = 2.98, 95% CI: (1.57, 5.67)] and chewing khat [AOR = 8.99, 95% CI: (3.84, 21.06)]. Conclusion Significant proportion of unmarried high school female students have started pre-marital sexual debut. The finding suggests the need for communicating and supporting school students to help them make informed and safer decisions on their sexual behavior. Therefore, Bahir dar city administration health and education bureau should design persistent and effective health education to decrease pre-marital sexual debut in unmarried female students. PMID:24885739

Jobs and the resource curse in the sun: The effects of oil production on female labor force participation in California counties from 1980-2010

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Zavala, Gabriel

This study aims to evaluate the relationship between oil income and the female labor force participation rate in California for the years of 1980, 1990, 2000 and 2010 using panel linear regression models. This study also aims to visualize the spatial patterns of both variables in California through Hot Spot analysis at the county level for the same years. The regression found no sign of a relationship between oil income and female labor force participation rate but did find evidence of a positive relationship between two income control variables and the female labor force participation rate. The hot spot analysis also found that female labor force participation cold spots are not spatially correlated with oil production hot spots. These findings contribute new methodologies at a finer scale to the very nuanced discussion of the resource curse in the United States.

Practical Aspects of Log-ratio Coordinate Representations in Regression with Compositional Response

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Fišerová Eva

2016-10-01

Full Text Available Regression analysis with compositional response, observations carrying relative information, is an appropriate tool for statistical modelling in many scientific areas (e.g. medicine, geochemistry, geology, economics. Even though this technique has been recently intensively studied, there are still some practical aspects that deserve to be further analysed. Here we discuss the issue related to the coordinate representation of compositional data. It is shown that linear relation between particular orthonormal coordinates and centred log-ratio coordinates can be utilized to simplify the computation concerning regression parameters estimation and hypothesis testing. To enhance interpretation of regression parameters, the orthogonal coordinates and their relation with orthonormal and centred log-ratio coordinates are presented. Further we discuss the quality of prediction in different coordinate system. It is shown that the mean squared error (MSE for orthonormal coordinates is less or equal to the MSE for log-transformed data. Finally, an illustrative real-world example from geology is presented.

Are female healthcare workers at higher risk of occupational injury?

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Alamgir, Hasanat; Yu, Shicheng; Drebit, Sharla; Fast, Catherine; Kidd, Catherine

2009-05-01

Differential risks of occupational injuries by gender have been examined across various industries. With the number of employees in healthcare rising and an overwhelming proportion of this workforce being female, it is important to address this issue in this growing sector. To determine whether compensated work-related injuries among females are higher than their male colleagues in the British Columbia healthcare sector. Incidents of occupational injury resulting in compensated days lost from work over a 1-year period for all healthcare workers were extracted from a standardized operational database and the numbers of productive hours were obtained from payroll data. Injuries were grouped into all injuries and musculoskeletal injuries (MSIs). Detailed analysis was conducted using Poisson regression modelling. A total of 42 332 employees were included in the study of whom 11% were male and 89% female. When adjusted for age, occupation, sub-sector, employment category, health region and facility, female workers had significantly higher risk of all injuries [rate ratio (95% CI) = 1.58 (1.24-2.01)] and MSIs [1.43 (1.11-1.85)] compared to their male colleagues. Occupational health and safety initiatives should be gender sensitive and developed accordingly.

Tumor regression patterns in retinoblastoma

International Nuclear Information System (INIS)

Zafar, S.N.; Siddique, S.N.; Zaheer, N.

2016-01-01

To observe the types of tumor regression after treatment, and identify the common pattern of regression in our patients. Study Design: Descriptive study. Place and Duration of Study: Department of Pediatric Ophthalmology and Strabismus, Al-Shifa Trust Eye Hospital, Rawalpindi, Pakistan, from October 2011 to October 2014. Methodology: Children with unilateral and bilateral retinoblastoma were included in the study. Patients were referred to Pakistan Institute of Medical Sciences, Islamabad, for chemotherapy. After every cycle of chemotherapy, dilated funds examination under anesthesia was performed to record response of the treatment. Regression patterns were recorded on RetCam II. Results: Seventy-four tumors were included in the study. Out of 74 tumors, 3 were ICRB group A tumors, 43 were ICRB group B tumors, 14 tumors belonged to ICRB group C, and remaining 14 were ICRB group D tumors. Type IV regression was seen in 39.1% (n=29) tumors, type II in 29.7% (n=22), type III in 25.6% (n=19), and type I in 5.4% (n=4). All group A tumors (100%) showed type IV regression. Seventeen (39.5%) group B tumors showed type IV regression. In group C, 5 tumors (35.7%) showed type II regression and 5 tumors (35.7%) showed type IV regression. In group D, 6 tumors (42.9%) regressed to type II non-calcified remnants. Conclusion: The response and success of the focal and systemic treatment, as judged by the appearance of different patterns of tumor regression, varies with the ICRB grouping of the tumor. (author)

Correlates of psychological distress, burnout, and resilience among Chinese female nurses

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ZOU, Guiyuan; SHEN, Xiuying; TIAN, Xiaohong; LIU, Chunqin; LI, Guopeng; KONG, Linghua; LI, Ping

2016-01-01

The present survey investigated the association between resilience, burnout and psychological distress among Chinese female nurses. A total of 366 female nurses were enrolled in our study. A series of self-reported questionnaires that dispose of the following constructs: psychological distress, burnout, and resilience were estimated. The hierarchical linear regression models were used to evaluate the mediating effect of resilience on the relationship between burnout and psychological distress. Results of the survey showed 85.5% nurses experienced psychological distress. Resilience was negatively related to psychological distress and burnout whereas burnout was positively associated with psychological distress. Mediation analysis revealed that resilience could partially mediate the relationship between the dimensions of emotional exhaustion, depersonalization, and psychological distress. This study highlights the mediator of resilience between burnout and psychological distress of female nurses. As such, interventions that attend to resilience training may be the focus for future clinical and research endeavors. PMID:27021058

Analysis of Palm Oil Production, Export, and Government Consumption to Gross Domestic Product of Five Districts in West Kalimantan by Panel Regression

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Sulistianingsih, E.; Kiftiah, M.; Rosadi, D.; Wahyuni, H.

2017-04-01

Gross Domestic Product (GDP) is an indicator of economic growth in a region. GDP is a panel data, which consists of cross-section and time series data. Meanwhile, panel regression is a tool which can be utilised to analyse panel data. There are three models in panel regression, namely Common Effect Model (CEM), Fixed Effect Model (FEM) and Random Effect Model (REM). The models will be chosen based on results of Chow Test, Hausman Test and Lagrange Multiplier Test. This research analyses palm oil about production, export, and government consumption to five district GDP are in West Kalimantan, namely Sanggau, Sintang, Sambas, Ketapang and Bengkayang by panel regression. Based on the results of analyses, it concluded that REM, which adjusted-determination-coefficient is 0,823, is the best model in this case. Also, according to the result, only Export and Government Consumption that influence GDP of the districts.

Combining Alphas via Bounded Regression

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Zura Kakushadze

2015-11-01

Full Text Available We give an explicit algorithm and source code for combining alpha streams via bounded regression. In practical applications, typically, there is insufficient history to compute a sample covariance matrix (SCM for a large number of alphas. To compute alpha allocation weights, one then resorts to (weighted regression over SCM principal components. Regression often produces alpha weights with insufficient diversification and/or skewed distribution against, e.g., turnover. This can be rectified by imposing bounds on alpha weights within the regression procedure. Bounded regression can also be applied to stock and other asset portfolio construction. We discuss illustrative examples.

riskRegression

DEFF Research Database (Denmark)

Ozenne, Brice; Sørensen, Anne Lyngholm; Scheike, Thomas

2017-01-01

In the presence of competing risks a prediction of the time-dynamic absolute risk of an event can be based on cause-specific Cox regression models for the event and the competing risks (Benichou and Gail, 1990). We present computationally fast and memory optimized C++ functions with an R interface...... for predicting the covariate specific absolute risks, their confidence intervals, and their confidence bands based on right censored time to event data. We provide explicit formulas for our implementation of the estimator of the (stratified) baseline hazard function in the presence of tied event times. As a by...... functionals. The software presented here is implemented in the riskRegression package....

Econometric analysis of realized covariation: high frequency based covariance, regression, and correlation in financial economics

DEFF Research Database (Denmark)

Barndorff-Nielsen, Ole Eiler; Shephard, N.

2004-01-01

This paper analyses multivariate high frequency financial data using realized covariation. We provide a new asymptotic distribution theory for standard methods such as regression, correlation analysis, and covariance. It will be based on a fixed interval of time (e.g., a day or week), allowing...... the number of high frequency returns during this period to go to infinity. Our analysis allows us to study how high frequency correlations, regressions, and covariances change through time. In particular we provide confidence intervals for each of these quantities....

Estimation of Stature from Foot Dimensions and Stature among South Indian Medical Students Using Regression Models

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Rajesh D. R

2015-01-01

Full Text Available Background: At times fragments of soft tissues are found disposed off in the open, in ditches at the crime scene and the same are brought to forensic experts for the purpose of identification and such type of cases pose a real challenge. Objectives: This study was aimed at developing a methodology which could help in personal identification by studying the relation between foot dimensions and stature among south subjects using regression models. Material and Methods: Stature and foot length of 100 subjects (age range 18-22 years were measured. Linear regression equations for stature estimation were calculated. Result: The correlation coefficients between stature and foot lengths were found to be positive and statistically significant. Height = 98.159 + 3.746 × FLRT (r = 0.821 and Height = 91.242 + 3.284 × FLRT (r = 0.837 are the regression formulas from foot lengths for males and females respectively. Conclusion: The regression equation derived in the study can be used reliably for estimation of stature in a diverse population group thus would be of immense value in the field of personal identification especially from mutilated bodies or fragmentary remains.

HIV due to female sex work: regional and global estimates.

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Annette Prüss-Ustün

Full Text Available Female sex workers (FSWs are at high risk of HIV infection. Our objective was to determine the proportion of HIV prevalence in the general female adult population that is attributable to the occupational exposure of female sex work, due to unprotected sexual intercourse.Population attributable fractions of HIV prevalence due to female sex work were estimated for 2011. A systematic search was conducted to retrieve required input data from available sources. Data gaps of HIV prevalence in FSWs for 2011 were filled using multilevel modeling and multivariate linear regression. The fraction of HIV attributable to female sex work was estimated as the excess HIV burden in FSWs deducting the HIV burden in FSWs due to injecting drug use.An estimated fifteen percent of HIV in the general female adult population is attributable to (unsafe female sex work. The region with the highest attributable fraction is Sub Saharan Africa, but the burden is also substantial for the Caribbean, Latin America and South and Southeast Asia. We estimate 106,000 deaths from HIV are a result of female sex work globally, 98,000 of which occur in Sub-Saharan Africa. If HIV prevalence in other population groups originating from sexual contact with FSWs had been considered, the overall attributable burden would probably be much larger.Female sex work is an important contributor to HIV transmission and the global HIV burden. Effective HIV prevention measures exist and have been successfully targeted at key populations in many settings. These must be scaled up.FSWs suffer from high HIV burden and are a crucial core population for HIV transmission. Surveillance, prevention and treatment of HIV in FSWs should benefit both this often neglected vulnerable group and the general population.

HIV Due to Female Sex Work: Regional and Global Estimates

Science.gov (United States)

Prüss-Ustün, Annette; Wolf, Jennyfer; Driscoll, Tim; Degenhardt, Louisa; Neira, Maria; Calleja, Jesus Maria Garcia

2013-01-01

Introduction Female sex workers (FSWs) are at high risk of HIV infection. Our objective was to determine the proportion of HIV prevalence in the general female adult population that is attributable to the occupational exposure of female sex work, due to unprotected sexual intercourse. Methods Population attributable fractions of HIV prevalence due to female sex work were estimated for 2011. A systematic search was conducted to retrieve required input data from available sources. Data gaps of HIV prevalence in FSWs for 2011 were filled using multilevel modeling and multivariate linear regression. The fraction of HIV attributable to female sex work was estimated as the excess HIV burden in FSWs deducting the HIV burden in FSWs due to injecting drug use. Results An estimated fifteen percent of HIV in the general female adult population is attributable to (unsafe) female sex work. The region with the highest attributable fraction is Sub Saharan Africa, but the burden is also substantial for the Caribbean, Latin America and South and Southeast Asia. We estimate 106,000 deaths from HIV are a result of female sex work globally, 98,000 of which occur in Sub-Saharan Africa. If HIV prevalence in other population groups originating from sexual contact with FSWs had been considered, the overall attributable burden would probably be much larger. Discussion Female sex work is an important contributor to HIV transmission and the global HIV burden. Effective HIV prevention measures exist and have been successfully targeted at key populations in many settings. These must be scaled up. Conclusion FSWs suffer from high HIV burden and are a crucial core population for HIV transmission. Surveillance, prevention and treatment of HIV in FSWs should benefit both this often neglected vulnerable group and the general population. PMID:23717432

Borderline Personality Disorder as a Female Phenotypic Expression of Psychopathy?

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Sprague, Jenessa; Javdani, Shabnam; Sadeh, Naomi; Newman, Joseph P.; Verona, Edelyn

2011-01-01

Evidence suggests that the combination of the interpersonal-affective (F1) and impulsive-antisocial (F2) features of psychopathy may be associated with borderline personality disorder (BPD), specifically among women (e.g., Coid, 1993; Hicks, Vaidyana-than, & Patrick, 2010). However, empirical research explicitly examining gendered relationships between BPD and psychopathy factors is lacking. To further inform this area of research, we investigated the hypothesis that the interplay between the two psychopathy factors is associated with BPD among women across two studies. Study 1 consisted of a college sample of 318 adults (51% women), and Study 2 consisted of a large sample of 488 female prisoners. The interpersonal-affective (F1) and impulsiveantisocial psychopathy (F2) scores, measured with self-report and clinician-rated indices, respectively, were entered as explanatory variables in regression analyses to investigate their unique contributions to BPD traits. Across two independent samples, results indicated that the interaction of high F1 and F2 psychopathy scores was associated with BPD in women. This association was found to be specific to women in Study 1. These results suggest that BPD and psychopathy, at least as they are measured by current instruments, overlap in women and, accordingly, may reflect gender-differentiated phenotypic expressions of similar dispositional vulnerabilities. PMID:22452756

The impact of psychological stress on men's judgements of female body size.

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Viren Swami

Full Text Available BACKGROUND: Previous work has suggested that the experience of psychological stress may influence physical attractiveness ideals, but most evidence in favour of this hypothesis remains archival. The objective of this study was to experimentally investigate the impact of stress on men's judgements of female body size. METHODS: Men were randomly assigned to either an experimental group, in which they took part in a task that heightened stress (experimental group, n = 41 or in which they did not take part in such a task (control group, n = 40. Both groups rated the attractiveness of female bodies varying in size from emaciated to obese, completed a measure of appetite sensation, and had their body mass indices (BMIs measured. RESULTS: Between-groups analyses showed that the experimental group was matched with the control group in terms of mean age, BMI, and appetite sensation. Further analyses showed that men in the experimental group rated a significantly heavier female body size as maximally attractive than the control group. Men in the experimental group also rated heavier female bodies as more attractive and idealised a wider range of female figures than did the control group. CONCLUSION: This study found that the experience of stress was associated with a preference among men for heavier female body sizes. These results indicate that human attractiveness judgements are sensitive to variations in local ecologies and reflect adaptive strategies for dealing with changing environmental conditions.

Regression in autistic spectrum disorders.

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Stefanatos, Gerry A

2008-12-01

A significant proportion of children diagnosed with Autistic Spectrum Disorder experience a developmental regression characterized by a loss of previously-acquired skills. This may involve a loss of speech or social responsitivity, but often entails both. This paper critically reviews the phenomena of regression in autistic spectrum disorders, highlighting the characteristics of regression, age of onset, temporal course, and long-term outcome. Important considerations for diagnosis are discussed and multiple etiological factors currently hypothesized to underlie the phenomenon are reviewed. It is argued that regressive autistic spectrum disorders can be conceptualized on a spectrum with other regressive disorders that may share common pathophysiological features. The implications of this viewpoint are discussed.

Item Response Theory Modeling and Categorical Regression Analyses of the Five-Factor Model Rating Form: A Study on Italian Community-Dwelling Adolescent Participants and Adult Participants.

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Fossati, Andrea; Widiger, Thomas A; Borroni, Serena; Maffei, Cesare; Somma, Antonella

2017-06-01

To extend the evidence on the reliability and construct validity of the Five-Factor Model Rating Form (FFMRF) in its self-report version, two independent samples of Italian participants, which were composed of 510 adolescent high school students and 457 community-dwelling adults, respectively, were administered the FFMRF in its Italian translation. Adolescent participants were also administered the Italian translation of the Borderline Personality Features Scale for Children-11 (BPFSC-11), whereas adult participants were administered the Italian translation of the Triarchic Psychopathy Measure (TriPM). Cronbach α values were consistent with previous findings; in both samples, average interitem r values indicated acceptable internal consistency for all FFMRF scales. A multidimensional graded item response theory model indicated that the majority of FFMRF items had adequate discrimination parameters; information indices supported the reliability of the FFMRF scales. Both categorical (i.e., item-level) and scale-level regression analyses suggested that the FFMRF scores may predict a nonnegligible amount of variance in the BPFSC-11 total score in adolescent participants, and in the TriPM scale scores in adult participants.

Confirmatory factor analysis of the female sexual function index.

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Opperman, Emily A; Benson, Lindsay E; Milhausen, Robin R

2013-01-01

The Female Sexual Functioning Index (Rosen et al., 2000 ) was designed to assess the key dimensions of female sexual functioning using six domains: desire, arousal, lubrication, orgasm, satisfaction, and pain. A full-scale score was proposed to represent women's overall sexual function. The fifth revision to the Diagnostic and Statistical Manual (DSM) is currently underway and includes a proposal to combine desire and arousal problems. The objective of this article was to evaluate and compare four models of the Female Sexual Functioning Index: (a) single-factor model, (b) six-factor model, (c) second-order factor model, and (4) five-factor model combining the desire and arousal subscales. Cross-sectional and observational data from 85 women were used to conduct a confirmatory factor analysis on the Female Sexual Functioning Index. Local and global goodness-of-fit measures, the chi-square test of differences, squared multiple correlations, and regression weights were used. The single-factor model fit was not acceptable. The original six-factor model was confirmed, and good model fit was found for the second-order and five-factor models. Delta chi-square tests of differences supported best fit for the six-factor model validating usage of the six domains. However, when revisions are made to the DSM-5, the Female Sexual Functioning Index can adapt to reflect these changes and remain a valid assessment tool for women's sexual functioning, as the five-factor structure was also supported.

Understanding logistic regression analysis

OpenAIRE

Sperandei, Sandro

2014-01-01

Logistic regression is used to obtain odds ratio in the presence of more than one explanatory variable. The procedure is quite similar to multiple linear regression, with the exception that the response variable is binomial. The result is the impact of each variable on the odds ratio of the observed event of interest. The main advantage is to avoid confounding effects by analyzing the association of all variables together. In this article, we explain the logistic regression procedure using ex...

Increased Risk of Smoking in Female Adolescents Who Had Childhood ADHD.

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Elkins, Irene J; Saunders, Gretchen R B; Malone, Stephen M; Keyes, Margaret A; Samek, Diana R; McGue, Matt; Iacono, William G

2018-01-01

This study examined the effects of childhood attention deficit hyperactivity disorder (ADHD) symptoms, both inattention and hyperactivity-impulsivity, on the development of smoking in male and female adolescents. Twin difference methods were used to control for shared genetic and environmental confounders in three population-based, same-sex twin samples (N=3,762; 64% monozygotic). One cohort oversampled female adolescents with ADHD beginning in childhood. Regressions of childhood inattentive and hyperactive-impulsive symptoms were conducted to predict smoking outcomes by age 17. ADHD effects were divided into those shared between twins in the pair and those nonshared, or different within pairs. Adolescents who had more severe ADHD symptoms as children were more likely to initiate smoking and to start smoking younger. The association of ADHD symptoms with daily smoking, number of cigarettes per day, and nicotine dependence was greater in females than in males. Monozygotic female twins with greater attentional problems than their co-twins had greater nicotine involvement, consistent with possible causal influence. These effects remained when co-occurring externalizing behaviors and stimulant medication were considered. Hyperactivity-impulsivity, while also more strongly related to smoking for female adolescents, appeared primarily noncausal. Smoking initiation and escalation are affected differentially by ADHD subtype and gender. The association of inattention with smoking in female adolescents may be causal, whereas hyperactivity-impulsivity appears to act indirectly, through shared propensities for both ADHD and smoking.

[Influencing factors for reproductive health of female workers in petrochemical industry].

Science.gov (United States)

Kou, Z X; Wang, S L; Chen, Z L; He, Y H; Yu, W L; Mei, L Y; Zhang, H D

2018-02-20

Objective: To investigate the reproductive health status of female workers in petrochemical industry, and to provide a reference for improving reproductive health status and developing preventive and control measures for female workers in petrochemical industry. Methods: A face-to-face questionnaire survey was performed from January to October, 2016. The Questionnaire on Women's Reproductive Health was used to investigate the reproductive health of female workers in petrochemical industry. The multivariate logistic regression model was used to identify the influencing factors for reproductive health of female workers in petrochemical industry. Results: Among the 7485 female workers, 1 268 (40.9%) had abnormal menstrual period, 1 437 (46.4%) had abnormal menstrual volume, 177 (28.5%) had hyperplasia of mammary glands, and 1 807 (24.6%) had gynecological inflammation. The reproductive system diseases in female workers in petrochemical industry were associated with the factors including age, marital status, education level, unhealthy living habits, abortion, overtime work, work shift, workload, video operation, occupational exposure, positive events, and negative events, and among these factors, negative events (odds ratio[ OR ]= 1.856) , unhealthy living habits ( OR =1.542) , and positive events ( OR =1.516) had greater impact on reproductive system diseases. Conclusion: Many chemical substances in the occupational environment of petrochemical industry can cause damage to the reproductive system, which not only affects the health of the female workers, but also poses potential threats to the health of their offspring. Occupational exposure, unhealthy living habits, overtime work, and work shift have great influence on reproductive system diseases in female workers.

Nonparametric regression using the concept of minimum energy

International Nuclear Information System (INIS)

Williams, Mike

2011-01-01

It has recently been shown that an unbinned distance-based statistic, the energy, can be used to construct an extremely powerful nonparametric multivariate two sample goodness-of-fit test. An extension to this method that makes it possible to perform nonparametric regression using multiple multivariate data sets is presented in this paper. The technique, which is based on the concept of minimizing the energy of the system, permits determination of parameters of interest without the need for parametric expressions of the parent distributions of the data sets. The application and performance of this new method is discussed in the context of some simple example analyses.

Construction of risk prediction model of type 2 diabetes mellitus based on logistic regression

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Li Jian

2017-01-01

Full Text Available Objective: to construct multi factor prediction model for the individual risk of T2DM, and to explore new ideas for early warning, prevention and personalized health services for T2DM. Methods: using logistic regression techniques to screen the risk factors for T2DM and construct the risk prediction model of T2DM. Results: Male’s risk prediction model logistic regression equation: logit(P=BMI × 0.735+ vegetables × (−0.671 + age × 0.838+ diastolic pressure × 0.296+ physical activity× (−2.287 + sleep ×(−0.009 +smoking ×0.214; Female’s risk prediction model logistic regression equation: logit(P=BMI ×1.979+ vegetables× (−0.292 + age × 1.355+ diastolic pressure× 0.522+ physical activity × (−2.287 + sleep × (−0.010.The area under the ROC curve of male was 0.83, the sensitivity was 0.72, the specificity was 0.86, the area under the ROC curve of female was 0.84, the sensitivity was 0.75, the specificity was 0.90. Conclusion: This study model data is from a compared study of nested case, the risk prediction model has been established by using the more mature logistic regression techniques, and the model is higher predictive sensitivity, specificity and stability.

Comparing Female Victims of Separation/Divorce Assault across Geographical Regions

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Walter S DeKeseredy

2013-04-01

Full Text Available Recent analyses of National Crime Victimization Survey (NCVS data show that male-to-female separation/divorce assault varies across geographic regions in the United States, with rural rates of such woman abuse being higher than those for suburban and urban areas. Using the same data set, the main objective of this paper is to present the results of an investigation into whether characteristics of female victims of separation/divorce assault also differ across urban, suburban, and rural communities.

Linear regression in astronomy. II

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Feigelson, Eric D.; Babu, Gutti J.

1992-01-01

A wide variety of least-squares linear regression procedures used in observational astronomy, particularly investigations of the cosmic distance scale, are presented and discussed. The classes of linear models considered are (1) unweighted regression lines, with bootstrap and jackknife resampling; (2) regression solutions when measurement error, in one or both variables, dominates the scatter; (3) methods to apply a calibration line to new data; (4) truncated regression models, which apply to flux-limited data sets; and (5) censored regression models, which apply when nondetections are present. For the calibration problem we develop two new procedures: a formula for the intercept offset between two parallel data sets, which propagates slope errors from one regression to the other; and a generalization of the Working-Hotelling confidence bands to nonstandard least-squares lines. They can provide improved error analysis for Faber-Jackson, Tully-Fisher, and similar cosmic distance scale relations.

Perceived and Actual Behavior in Female Sexual Assertiveness: A Within-Couple Analysis in Hong Kong.

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Zhang, Huiping; Yip, Paul S F

2018-01-02

Studies in female sexual assertiveness have generally focused on individuals rather than couples, and little research has been conducted in the Chinese context. This study examined perceived and actual female sexual assertiveness at the couple level, and also explored its impact on marital and sexual satisfaction with a representative sample of 770 couples in Hong Kong. The results showed that husbands reported a higher level of acceptance of female sexual assertiveness in both perception and actual behavior; furthermore, couples reported greater congruence in their perception of female sexual initiation than actual behavior. Multiple logistic regressions showed that actual female sexual assertiveness, not the perception of it, affects both spouses' marital and sexual satisfaction. Compared with couples in which neither accepted female sexual initiation in practice, husbands where both spouses accepted this were more likely to be satisfied with the marriage. Husbands who accepted female sexual refusal whilst their wives did not were also more likely to be satisfied with both the marital and sexual relationship. Similarly, wives who did accept female sexual assertiveness but whose husbands did not were more likely to be satisfied with both the marital and sexual relationship.

Sexual harassment and female gregariousness in the South American sea lion, Otaria flavescens

Science.gov (United States)

Cappozzo, Humberto L.; Túnez, Juan I.; Cassini, Marcelo H.

2008-07-01

Most colonial pinnipeds form extreme clusters of breeding females that cannot be entirely explained by the distribution of sites for reproduction. Avoidance of male harassment has been postulated as an important determinant of reproductive aggregation in this group of mammals. Female gregariousness can reduce harassment by resident males by two mechanisms; directly by the ‘dilution effect’ or indirectly because resident males that defend large female groups are less harassing. In order to investigate the relationship between male harassment and female gregariousness in relation to the size of breeding groups, we analysed the behaviour of dominant males and their females in a breeding colony of Otaria flavescens. Females in large breeding groups received less harassment by resident males due to dilution effects and because males that defended a large group interacted less frequently with females than males with small groups.

A Matlab program for stepwise regression

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Yanhong Qi

2016-03-01

Full Text Available The stepwise linear regression is a multi-variable regression for identifying statistically significant variables in the linear regression equation. In present study, we presented the Matlab program of stepwise regression.

Incidence of Domestic Violence Against Pregnant Females After the Great East Japan Earthquake in Miyagi Prefecture: The Japan Environment and Children's Study.

Science.gov (United States)

Sakurai, Kasumi; Nishigori, Hidekazu; Nishigori, Toshie; Mizuno, Satoshi; Obara, Taku; Iwama, Noriyuki; Watanabe, Zen; Ishikuro, Mami; Tatsuta, Nozomi; Nishijima, Ichiko; Sugawara, Junichi; Fujiwara, Ikuma; Arima, Takahiro; Kuriyama, Shinichi; Metoki, Hirohito; Takahashi, Fumiaki; Nakai, Kunihiko; Yaegashi, Nobuo

2017-04-01

This study aimed to clarify the correlation between the 2011 Great East Japan Earthquake and domestic violence (DV) against pregnant females after the disaster in Miyagi Prefecture, an area damaged by the earthquake and tsunami. We analyzed 7600 pregnant females from June to December 2011. The incidence of physical and mental DV and the proportions in the inland, north coastal, and south coastal areas of Miyagi Prefecture and nationwide were calculated, and a chi-square test was conducted for comparison. The risk factors for DV were estimated with multivariate logistic regression analyses on a prefecture-wide basis. The incidence levels for physical DV were found to be 5.9% in the north coastal area, which was significantly higher than in the inland area (1.3%, P=0.0007) and nationwide (1.5%, P<0.0001). There were no significant differences in the incidence of mental DV between the 3 areas in Miyagi Prefecture (inland 15.2%, north coast 15.7%, and south coast 18.8%) or nationwide (13.8%). Experiencing disease or injury in someone close and changes in the family structure were significantly associated with mental DV in Miyagi Prefecture. Continuous monitoring and support for pregnant females may be necessary to address this issue in disaster-affected areas. (Disaster Med Public Health Preparedness. 2017;11:216-226).

Applicability of the Tanaka-Johnston and Moyers mixed dentition analyses in Northeast Han Chinese.

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Sherpa, Jangbu; Sah, Gopal; Rong, Zeng; Wu, Lipeng

2015-06-01

To assess applicability of the Tanaka-Johnston and Moyers prediction methods in a Han ethnic group from Northeast China and to develop prediction equations for this same population. Cross-sectional study. Department of Orthodontics, School of Stomatology, Jiamusi University, Heilongjiang, China. A total of 130 subjects (65 male and 65 female) aged 16-21 years from a Han ethnic group of Northeast China were recruited from dental students and patients seeking orthodontic treatment. Ethnicity was verified by questionnaire. Mesio-distal tooth width was measured using Digital Vernier calipers. Predicted values were obtained from the Tanaka-Johnston and Moyers methods in both arches were compared with the actual measured widths. Based on regression analysis, prediction equations were developed. Tanaka-Johnston equations were not precise, except for the upper arch in males. However, the Moyers 85th percentile in the upper arch and 75th percentile in the lower arch predicted the sum precisely in males. For females, the Moyers 75th percentile predicted the sum precisely for the upper arch, but none of the Moyers percentiles predicted in the lower arch. Both the Tanaka-Johnston and Moyers method may not be applied universally without question. Hence, it may be safer to develop regression equations for specific populations. Validating studies must be conducted to confirm the precision of these newly developed regression equations.

Quantile regression theory and applications

CERN Document Server

Davino, Cristina; Vistocco, Domenico

2013-01-01

A guide to the implementation and interpretation of Quantile Regression models This book explores the theory and numerous applications of quantile regression, offering empirical data analysis as well as the software tools to implement the methods. The main focus of this book is to provide the reader with a comprehensivedescription of the main issues concerning quantile regression; these include basic modeling, geometrical interpretation, estimation and inference for quantile regression, as well as issues on validity of the model, diagnostic tools. Each methodological aspect is explored and

Fungible weights in logistic regression.

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Jones, Jeff A; Waller, Niels G

2016-06-01

In this article we develop methods for assessing parameter sensitivity in logistic regression models. To set the stage for this work, we first review Waller's (2008) equations for computing fungible weights in linear regression. Next, we describe 2 methods for computing fungible weights in logistic regression. To demonstrate the utility of these methods, we compute fungible logistic regression weights using data from the Centers for Disease Control and Prevention's (2010) Youth Risk Behavior Surveillance Survey, and we illustrate how these alternate weights can be used to evaluate parameter sensitivity. To make our work accessible to the research community, we provide R code (R Core Team, 2015) that will generate both kinds of fungible logistic regression weights. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Determination of the Static Anthropometric Characteristics of Iranian Microscope Users Via Regression Model

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Toktam Balandeh

2016-04-01

Full Text Available Background: Anthropometry is a branch of Ergonomics that considers the measurement and description of the human body dimensions. Accordingly, equipment, environments, and workstations should be designed using user-centered design processes. Anthropometric dimensions differ considerably across gender, race, ethnicity and age, taking into account ergonomic and anthropometric principles. The aim of this study was to determine anthropometric characteristics of microscope users and provide a regression model for anthropometric dimensions. Methods: In this cross-sectional study, anthropometric dimensions (18 dimensions of the microscope users (N=174; 78 males and 96 females in Shiraz were measured. Instruments included a Studio meter, 2 type calipers, adjustable seats, a 40-cm ruler, a tape measure, and scales. The study data were analyzed using SPSS, version 20. Results: The means of male and female microscope users’ age were 31.64±8.86 and 35±10.9 years, respectively and their height were 161.03±6.87cm and 174.81±5.45cm, respectively. The results showed that sitting and standing eye height and sitting horizontal range of accessibility had a significant correlation with stature. Conclusion: The established anthropometric database can be used as a source for designing workstations for working with microscopes in this group of users. The regression analysis showed that three dimensions, i.e. standing eye height, sitting eye height, and horizontal range of accessibility sitting had a significant correlation with stature. Therefore, given one’s stature, these dimensions can be obtained with less measurement.

Male sexual harassment alters female social behaviour towards other females.

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Darden, Safi K; Watts, Lauren

2012-04-23

Male harassment of females to gain mating opportunities is a consequence of an evolutionary conflict of interest between the sexes over reproduction and is common among sexually reproducing species. Male Trinidadian guppies Poecilia reticulata spend a large proportion of their time harassing females for copulations and their presence in female social groups has been shown to disrupt female-female social networks and the propensity for females to develop social recognition based on familiarity. In this study, we investigate the behavioural mechanisms that may lead to this disruption of female sociality. Using two experiments, we test the hypothesis that male presence will directly affect social behaviours expressed by females towards other females in the population. In experiment one, we tested for an effect of male presence on female shoaling behaviour and found that, in the presence of a free-swimming male guppy, females spent shorter amounts of time with other females than when in the presence of a free-swimming female guppy. In experiment two, we tested for an effect of male presence on the incidence of aggressive behaviour among female guppies. When males were present in a shoal, females exhibited increased levels of overall aggression towards other females compared with female only shoals. Our work provides direct evidence that the presence of sexually harassing males alters female-female social behaviour, an effect that we expect will be recurrent across taxonomic groups.

Effects of the distribution of female primates on the number of males.

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Laurel Mariah Carnes

Full Text Available The spatiotemporal distribution of females is thought to drive variation in mating systems, and hence plays a central role in understanding animal behavior, ecology and evolution. Previous research has focused on investigating the links between female spatiotemporal distribution and the number of males in haplorhine primates. However, important questions remain concerning the importance of spatial cohesion, the generality of the pattern across haplorhine and strepsirrhine primates, and the consistency of previous findings given phylogenetic uncertainty. To address these issues, we examined how the spatiotemporal distribution of females influences the number of males in primate groups using an expanded comparative dataset and recent advances in bayesian phylogenetic and statistical methods. Specifically, we investigated the effect of female distributional factors (female number, spatial cohesion, estrous synchrony, breeding season duration and breeding seasonality on the number of males in primate groups. Using bayesian approaches to control for uncertainty in phylogeny and the model of trait evolution, we found that the number of females exerted a strong influence on the number of males in primate groups. In a multiple regression model that controlled for female number, we found support for temporal effects, particularly involving female estrous synchrony: the number of males increases when females are more synchronously receptive. Similarly, the number of males increases in species with shorter birth seasons, suggesting that greater breeding seasonality makes defense of females more difficult for male primates. When comparing primate suborders, we found only weak evidence for differences in traits between haplorhines and strepsirrhines, and including suborder in the statistical models did not affect our conclusions or give compelling evidence for different effects in haplorhines and strepsirrhines. Collectively, these results demonstrate that

The Association between Cumulative Psychosocial Risk and Cervical HPV Infection Among Female Adolescents in a Free Vaccination Program

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Linares, Lourdes Oriana; Shankar, Viswanathan; Diaz, Angela; Nucci-Sack, Anne; Strickler, Howard D.; Peake, Ken; Weiss, Jocelyn; Burk, Robert D.; Schlecht, Nicolas F.

2016-01-01

Objective This study investigated the association of cervical Human Papillomavirus (HPV) infection with cumulative psychosocial risk reflecting family disadvantage, psychological distress, and unhealthy life style. Methods The sample (N=745) was comprised of sexually-active female adolescent patients (12-19 years), primarily ethnic minorities, enrolled in a free HPV vaccination program. Subjects completed questionnaires and provided cervical swabs for HPV DNA testing. Unweighted and weighted Principal Component Analyses (PCA) for categorical data were used to derive multi-systemic psychosocial risk indices using nine indicators: low socioeconomic status, lack of adult involvement, not attending high-school/college, history of treatment for depression/anxiety, antisocial/delinquent behavior, number of recent sexual partners, use of alcohol, use of drugs, and dependency risk for alcohol/drugs. The association between cervical HPV (any-type, high risk-types, vaccine-types) assayed by polymerase chain reaction and self-reported number of psychosocial risk indicators was estimated using multivariable logistic regression. Results Subjects had a median of three psychosocial risk indicators. Multiple logistic regression analyses showed associations with unweighted and weighted number of psychosocial indicators for HPV any-type (adjusted odds ratio [aOR]=1.1; 95% confidence interval [CI]: 1.0-1.2 ); with the strongest associations between weighted drug/alcohol use, drug/alcohol dependency risk, and antisocial/delinquent behavior and detection of HPV vaccine-types (aOR=1.5; 95%CI: 1.1-2.0) independent of number of recent sexual partners and vaccine dose (0-3). Conclusion Increased HPV infections including HPV vaccine-types were associated with greater number of psychosocial risk indicators even after controlling for demographics, sexual behavior, history of chlamydia, and vaccine dose. PMID:25985216

Application of logistic regression for landslide susceptibility zoning of Cekmece Area, Istanbul, Turkey

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Duman, T. Y.; Can, T.; Gokceoglu, C.; Nefeslioglu, H. A.; Sonmez, H.

2006-11-01

As a result of industrialization, throughout the world, cities have been growing rapidly for the last century. One typical example of these growing cities is Istanbul, the population of which is over 10 million. Due to rapid urbanization, new areas suitable for settlement and engineering structures are necessary. The Cekmece area located west of the Istanbul metropolitan area is studied, because the landslide activity is extensive in this area. The purpose of this study is to develop a model that can be used to characterize landslide susceptibility in map form using logistic regression analysis of an extensive landslide database. A database of landslide activity was constructed using both aerial-photography and field studies. About 19.2% of the selected study area is covered by deep-seated landslides. The landslides that occur in the area are primarily located in sandstones with interbedded permeable and impermeable layers such as claystone, siltstone and mudstone. About 31.95% of the total landslide area is located at this unit. To apply logistic regression analyses, a data matrix including 37 variables was constructed. The variables used in the forwards stepwise analyses are different measures of slope, aspect, elevation, stream power index (SPI), plan curvature, profile curvature, geology, geomorphology and relative permeability of lithological units. A total of 25 variables were identified as exerting strong influence on landslide occurrence, and included by the logistic regression equation. Wald statistics values indicate that lithology, SPI and slope are more important than the other parameters in the equation. Beta coefficients of the 25 variables included the logistic regression equation provide a model for landslide susceptibility in the Cekmece area. This model is used to generate a landslide susceptibility map that correctly classified 83.8% of the landslide-prone areas.

Embryonic Testicular Regression Syndrome Presenting as Primary Amenorrhea: A Case Report and Review of Disorders of Sexual Development.

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Hunter, J D; Pierce, S R; Calikoglu, A S; Howell, J O

2016-08-01

Sex development depends on the synchronous interaction of complicated genetic and hormonal events. Sex differentiation begins with sex determination, which is the assignment of the embryonic bipotential gonads as either testes or ovaries on the basis of transcriptional regulation. Hormonal regulation then directs the development of the male or female phenotype. Disruptions of this intricate cascade of events result in disorders of sexual development. A 16-year-old female adolescent presented with primary amenorrhea. Evaluation revealed female external genitalia, XY karyotype, absent gonadal tissue, and rudimentary Müllerian structures. On the basis of her constellation of findings, the most logical diagnosis was the rare embryonic testicular regression syndrome. A careful understanding of embryonic sexual development is critical to the evaluation of patients with disorders of sexual development. Copyright © 2016 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.

Cognitive-Affective Dimensions of Female Orgasm: The Role of Automatic Thoughts and Affect During Sexual Activity.

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Tavares, Inês M; Laan, Ellen T M; Nobre, Pedro J

2017-06-01

Cognitive-affective factors contribute to female sexual dysfunctions, defined as clinically significant difficulties in the ability to respond sexually or to experience sexual pleasure. Automatic thoughts and affect presented during sexual activity are acknowledged as maintenance factors for these difficulties. However, there is a lack of studies on the influence of these cognitive-affective dimensions regarding female orgasm. To assess the role of automatic thoughts and affect during sexual activity in predicting female orgasm occurrence and to investigate the mediator role of these variables in the relation between sexual activity and orgasm occurrence. Nine hundred twenty-six sexually active heterosexual premenopausal women reported on frequency of sexual activities and frequency of orgasm occurrence, cognitive factors, and social desirability. Participants completed the Sexual Modes Questionnaire-Automatic Thoughts Subscale, the Positive and Negative Affect Schedule, and the Socially Desirable Response Set. Multiple linear regressions and mediation analyses were performed, controlling for the effect of covariates such as social desirability, sociodemographic and medical characteristics, and relationship factors. The main outcome measurement was orgasm frequency as predicted and mediated by automatic thoughts and affect experienced during sexual activities. The presence of failure thoughts and lack of erotic thoughts during sexual activity significantly and negatively predicted female orgasm, whereas positive affect experienced during sexual activity significantly and positively predicted female orgasm. Moreover, negative automatic thoughts and positive affect during sexual activity were found to mediate the relation between sexual activity and female orgasm occurrence. These data suggest that the cognitive aspects of sexual involvement are critical to enhancing female orgasm experience and can aid the development of strategies that contemplate the central role

Investigation of relationship between social capital and quality of life in female headed families

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Rimaz, Shahnaz; Dastoorpoor, Maryam; Vesali, Samira; Saiepour, Narges; Nedjat, Saharnaz; Sadeghi, Masoumeh; Merghati Khoei, Effat

2015-01-01

Background: Although most studies on female-headed families focus on women's access to social support, the associations between social capital and quality of life in these families are unclear in many societies (such as Iran). This study aimed to determine the associations between social capital and quality of life in Iranian female headed families. Methods: This cross-sectional study was performed on 152 female-headed households supported by Tehran Municipality, district 9 from April 2011 to July 2012. Convenience sampling was employed. Data were collected using demographic questionnaire, the Iranian version of World Health Organization Quality of Life, and the Word Bank Social Capital. Descriptive and multiple regression methods were used to analyze the data. Results: The mean±SD age of participants was 50.8±13.8 years. Findings revealed that in quality of life, the domains of environment health and social relation received the lowest (9.87 ± 2.41) and the highest (12.61 ±3.43) scores respectively; and with respect to social capital, membership in groups and social trust had the least (19.61 ± 17.11) and the most (51.04 ± 17.37) scores, respectively. The multiple regression model revealed a significant positive association between total score of the quality of life and the total score for the social capital (p< 0.001). Conclusion: Findings suggest that quality of life of female-headed families and social capital domains are strongly related. This means that by improving the social capital, women’s life can also be improved. PMID:26793661

An introduction to using Bayesian linear regression with clinical data.

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Baldwin, Scott A; Larson, Michael J

2017-11-01

Statistical training psychology focuses on frequentist methods. Bayesian methods are an alternative to standard frequentist methods. This article provides researchers with an introduction to fundamental ideas in Bayesian modeling. We use data from an electroencephalogram (EEG) and anxiety study to illustrate Bayesian models. Specifically, the models examine the relationship between error-related negativity (ERN), a particular event-related potential, and trait anxiety. Methodological topics covered include: how to set up a regression model in a Bayesian framework, specifying priors, examining convergence of the model, visualizing and interpreting posterior distributions, interval estimates, expected and predicted values, and model comparison tools. We also discuss situations where Bayesian methods can outperform frequentist methods as well has how to specify more complicated regression models. Finally, we conclude with recommendations about reporting guidelines for those using Bayesian methods in their own research. We provide data and R code for replicating our analyses. Copyright © 2017 Elsevier Ltd. All rights reserved.

Estimation of stature from the foot and its segments in a sub-adult female population of North India

Science.gov (United States)

2011-01-01

Background Establishing personal identity is one of the main concerns in forensic investigations. Estimation of stature forms a basic domain of the investigation process in unknown and co-mingled human remains in forensic anthropology case work. The objective of the present study was to set up standards for estimation of stature from the foot and its segments in a sub-adult female population. Methods The sample for the study constituted 149 young females from the Northern part of India. The participants were aged between 13 and 18 years. Besides stature, seven anthropometric measurements that included length of the foot from each toe (T1, T2, T3, T4, and T5 respectively), foot breadth at ball (BBAL) and foot breadth at heel (BHEL) were measured on both feet in each participant using standard methods and techniques. Results The results indicated that statistically significant differences (p forensic examination. Stepwise multiple regression models tend to estimate stature more accurately than linear regression models in female sub-adults. PMID:22104433

Principal component regression analysis with SPSS.

Science.gov (United States)

Liu, R X; Kuang, J; Gong, Q; Hou, X L

2003-06-01

The paper introduces all indices of multicollinearity diagnoses, the basic principle of principal component regression and determination of 'best' equation method. The paper uses an example to describe how to do principal component regression analysis with SPSS 10.0: including all calculating processes of the principal component regression and all operations of linear regression, factor analysis, descriptives, compute variable and bivariate correlations procedures in SPSS 10.0. The principal component regression analysis can be used to overcome disturbance of the multicollinearity. The simplified, speeded up and accurate statistical effect is reached through the principal component regression analysis with SPSS.

Risk factors related to female breast cancer in regions of Northeast China: a 1:3 matched case-control population-based study.

Science.gov (United States)

Yu, Zhi-gang; Jia, Cun-xian; Geng, Cui-zhi; Tang, Jin-hai; Zhang, Jin; Liu, Li-yuan

2012-03-01

There has been an increase in the incidence of breast cancer in China, but no definite risk and protective factors for breast cancer have been identified in Chinese females. This study was designed to identify the risk factors for female breast cancer in North and East China. A 1:3 matched, case-control study was conducted. All of the subjects in the case and control groups were selected from a previous epidemiological survey of 122 058 females aged 25 to 70 years. Single and multiple Logistic regression analyses were used to study potential factors in the development of breast cancer. Significant differences at the level of α=0.20 between case and control groups were observed for the following factors: economic status, social status, family annual income, bean product consumption, body mass index (BMI), family history of breast cancer in the first or second degree, number of miscarriages, menstrual pattern, benign breast disease history, nipple leakage, inverted nipple, history of diabetes mellitus, history of hypertension, history of ovarian cyst, physical exercise, current and global quality of life satisfaction, healthy behavior and prevention, and scores of breast cancer-related knowledge. After Cox-regression model analysis (α=0.10), six factors were found to be significantly related to breast cancer, of which the ORs and 95%CIs were: BMI, 1.696 (1.169-2.460, P=0.005); benign breast disease history, 2.672 (0.848-8.416, P=0.093); family history of breast cancer, 7.080 (1.758-28.551, P=0.006); number of miscarriages, 1.738 (1.014-2.978, P=0.044); global quality of life satisfaction, 3.044 (1.804-5.136, P=0.000); healthy behavior and prevention, 3.294 (1.692-6.412, P=0.000). A comprehensive range of factors related to breast cancer was identified. Women should be educated about a healthy lifestyle, especially those with a family history of breast cancer or a personal history of benign breast disease.

Development of the rate of employment and unemployment of males and females in countries of EU15

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Milan Palát

2005-01-01

Full Text Available The paper is focused on the evaluation the rates of employment and unemployment of women, men and as a whole in countries of EU15. Rates of employment were evaluated in the period 1993–2002. Rates of unemployment were evaluated in the period 1994–2003. Employment of males in fifteen countries of EU is higher then employment of females. Unemployment of females in fifteen countries of EU is higher than unemployment of males and in opposite unemployment of females in Sweden is lower than unemployment of males. Trends of rates of male, female and total employment and unemployment are evaluated. Methods of regression and correlation analysis, development trends and cluster analysis were applied for the mathematical-statistical analysis.

Length bias correction in gene ontology enrichment analysis using logistic regression.

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Mi, Gu; Di, Yanming; Emerson, Sarah; Cumbie, Jason S; Chang, Jeff H

2012-01-01

When assessing differential gene expression from RNA sequencing data, commonly used statistical tests tend to have greater power to detect differential expression of genes encoding longer transcripts. This phenomenon, called "length bias", will influence subsequent analyses such as Gene Ontology enrichment analysis. In the presence of length bias, Gene Ontology categories that include longer genes are more likely to be identified as enriched. These categories, however, are not necessarily biologically more relevant. We show that one can effectively adjust for length bias in Gene Ontology analysis by including transcript length as a covariate in a logistic regression model. The logistic regression model makes the statistical issue underlying length bias more transparent: transcript length becomes a confounding factor when it correlates with both the Gene Ontology membership and the significance of the differential expression test. The inclusion of the transcript length as a covariate allows one to investigate the direct correlation between the Gene Ontology membership and the significance of testing differential expression, conditional on the transcript length. We present both real and simulated data examples to show that the logistic regression approach is simple, effective, and flexible.

Charismatic female leadership and gender

DEFF Research Database (Denmark)

Meret, Susi

2015-01-01

Research on the leadership and electorates of populist right-wing parties emphasizes that most of these parties are charismatic and male-dominated, both as regards their leadership and voters. However, while studies about the gender gap focus mainly on demand-side factors, such as electoral support......, socio-economic characteristics and the voters' attitudes towards issues such as immigration, those that analyse the role and position of gender issues are still rare. Similarly, or even more, overlooked is an analysis of the rhetoric, style, charisma and discourse of populist female leaders...

A Quantile Regression Approach to Estimating the Distribution of Anesthetic Procedure Time during Induction.

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Hsin-Lun Wu

Full Text Available Although procedure time analyses are important for operating room management, it is not easy to extract useful information from clinical procedure time data. A novel approach was proposed to analyze procedure time during anesthetic induction. A two-step regression analysis was performed to explore influential factors of anesthetic induction time (AIT. Linear regression with stepwise model selection was used to select significant correlates of AIT and then quantile regression was employed to illustrate the dynamic relationships between AIT and selected variables at distinct quantiles. A total of 1,060 patients were analyzed. The first and second-year residents (R1-R2 required longer AIT than the third and fourth-year residents and attending anesthesiologists (p = 0.006. Factors prolonging AIT included American Society of Anesthesiologist physical status ≧ III, arterial, central venous and epidural catheterization, and use of bronchoscopy. Presence of surgeon before induction would decrease AIT (p < 0.001. Types of surgery also had significant influence on AIT. Quantile regression satisfactorily estimated extra time needed to complete induction for each influential factor at distinct quantiles. Our analysis on AIT demonstrated the benefit of quantile regression analysis to provide more comprehensive view of the relationships between procedure time and related factors. This novel two-step regression approach has potential applications to procedure time analysis in operating room management.

Association between shift work and severity of depressive symptoms among female nurses: the Korea Nurses' Health Study.

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Lee, Hea Young; Kim, Mi Sun; Kim, OkSoo; Lee, Il-Hyun; Kim, Han-Kyoul

2016-03-01

To determine the prevalence of depression and the relationship between shift work and depression severity among female nurses in South Korea. Shift work has been associated with higher risks of depressive symptoms, but there is a dearth of research on nurses, particularly investigating the severity of depressive symptoms. Quantitative data including survey response from 9789 participants were analysed. Statistical analysis included descriptive, Spearman's correlation and multivariable ordinal logistic regression. The numbers of nurses according to the severity of depressive symptoms were 35.2% (n = 3445), 38.0% (n = 3716), 16.1% (n = 1578), 7.6% (n = 747) and 3.1% (n = 303) for normal, mild, moderate, severely moderate and severe level of depressive symptoms, respectively. After adjusting for sociodemographic and health behavioural factors, nurses who worked shifts had 1.519-times greater odds of experiencing a higher severity of depressive symptoms (OR = 1.519, CI = 1.380-1.674, P nurses who worked shifts and suggests that shift work may increase the severity of depressive symptoms among female nurses in South Korea. Nursing professionals, managers and health policy makers need to understand the factors influencing depressive symptoms and to use appropriate interventions based on the severity and not just the onset. © 2015 John Wiley & Sons Ltd.

Logistic regression models

CERN Document Server

Hilbe, Joseph M

2009-01-01

This book really does cover everything you ever wanted to know about logistic regression … with updates available on the author's website. Hilbe, a former national athletics champion, philosopher, and expert in astronomy, is a master at explaining statistical concepts and methods. Readers familiar with his other expository work will know what to expect-great clarity.The book provides considerable detail about all facets of logistic regression. No step of an argument is omitted so that the book will meet the needs of the reader who likes to see everything spelt out, while a person familiar with some of the topics has the option to skip "obvious" sections. The material has been thoroughly road-tested through classroom and web-based teaching. … The focus is on helping the reader to learn and understand logistic regression. The audience is not just students meeting the topic for the first time, but also experienced users. I believe the book really does meet the author's goal … .-Annette J. Dobson, Biometric...

Institutions and deforestation in the Brazilian amazon: a geographic regression discontinuity analysis

OpenAIRE

Bogetvedt, Ingvild Engen; Hauge, Mari Johnsrud

2017-01-01

This study explores the impact of institutional quality at the municipal level on deforestation in the Legal Amazon. We add to this insufficiently understood topic by implementing a geographic regression discontinuity design. By taking advantage of high-resolution spatial data on deforestation combined with an objective measure of corruption used as a proxy for institutional quality, we analyse 138 Brazilian municipalities in the period of 2002-2004. Our empirical findings show...

The relationship between depressive symptoms among female workers and job stress and sleep quality.

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Cho, Ho-Sung; Kim, Young-Wook; Park, Hyoung-Wook; Lee, Kang-Ho; Jeong, Baek-Geun; Kang, Yune-Sik; Park, Ki-Soo

2013-07-22

Recently, workers' mental health has become important focus in the field of occupational health management. Depression is a psychiatric illness with a high prevalence. The association between job stress and depressive symptoms has been demonstrated in many studies. Recently, studies about the association between sleep quality and depressive symptoms have been reported, but there has been no large-scaled study in Korean female workers. Therefore, this study was designed to investigate the relationship between job stress and sleep quality, and depressive symptoms in female workers. From Mar 2011 to Aug 2011, 4,833 female workers in the manufacturing, finance, and service fields at 16 workplaces in Yeungnam province participated in this study, conducted in combination with a worksite-based health checkup initiated by the National Health Insurance Service (NHIS). In this study, a questionnaire survey was carried out using the Korean Occupational Stress Scale-Short Form(KOSS-SF), Pittsburgh Sleep Quality Index(PSQI) and Center for Epidemiological Studies-Depression Scale(CES-D). The collected data was entered in the system and analyzed using the PASW (version 18.0) program. A correlation analysis, cross analysis, multivariate logistic regression analysis, and hierarchical multiple regression analysis were conducted. Among the 4,883 subjects, 978 subjects (20.0%) were in the depression group. Job stress(OR=3.58, 95% CI=3.06-4.21) and sleep quality(OR=3.81, 95% CI=3.18-4.56) were strongly associated with depressive symptoms. Hierarchical multiple regression analysis revealed that job stress displayed explanatory powers of 15.6% on depression while sleep quality displayed explanatory powers of 16.2%, showing that job stress and sleep quality had a closer relationship with depressive symptoms, compared to the other factors. The multivariate logistic regression analysis yielded odds ratios between the 7 subscales of job stress and depressive symptoms in the range of 1

Consequences of kriging and land use regression for PM2.5 predictions in epidemiologic analyses: insights into spatial variability using high-resolution satellite data.

Science.gov (United States)

Alexeeff, Stacey E; Schwartz, Joel; Kloog, Itai; Chudnovsky, Alexandra; Koutrakis, Petros; Coull, Brent A

2015-01-01

Many epidemiological studies use predicted air pollution exposures as surrogates for true air pollution levels. These predicted exposures contain exposure measurement error, yet simulation studies have typically found negligible bias in resulting health effect estimates. However, previous studies typically assumed a statistical spatial model for air pollution exposure, which may be oversimplified. We address this shortcoming by assuming a realistic, complex exposure surface derived from fine-scale (1 km × 1 km) remote-sensing satellite data. Using simulation, we evaluate the accuracy of epidemiological health effect estimates in linear and logistic regression when using spatial air pollution predictions from kriging and land use regression models. We examined chronic (long-term) and acute (short-term) exposure to air pollution. Results varied substantially across different scenarios. Exposure models with low out-of-sample R(2) yielded severe biases in the health effect estimates of some models, ranging from 60% upward bias to 70% downward bias. One land use regression exposure model with >0.9 out-of-sample R(2) yielded upward biases up to 13% for acute health effect estimates. Almost all models drastically underestimated the SEs. Land use regression models performed better in chronic effect simulations. These results can help researchers when interpreting health effect estimates in these types of studies.

The relationship between female adolescent self-esteem, decision making, and contraceptive behavior.

Science.gov (United States)

Commendador, Kathleen

2007-11-01

To examine the relationship between female adolescent self-esteem, decision making, and contraceptive behavior in multiethnic, 14- to 17-year-olds, residing on the Big Island of Hawaii. This was a descriptive cross-sectional survey design using a convenience sample of 98 female adolescents aged 14-17 who came to five different clinics on the Big Island of Hawaii for health care. Along with a brief demographic questionnaire, global self-esteem was measured by Rosenberg's Self-Esteem Scale, decision making was measured by the Flinders Adolescent Decision Making Questionnaire, and sexual activity and contraception use was measured by a nonnormed Sexual History and Contraceptive Use Questionnaire developed for this study. Descriptive statistics, logistic regression, and correlations were used to analyze associations and correlations between age, global self-esteem, decision self-esteem, decision coping (vigilant and maladaptive), and contraceptive use for sexually active female adolescents. No significant associations or correlations were found between age, global self-esteem, decision self-esteem, decision coping (vigilance), and the decision to use contraception in sexually active adolescent females. There was, however, significant negative correlation (p skills and stimulating thinking around not only sexual issues but also on relationship and communication in adolescent issues may facilitate more competent decision making. Understanding the relationship between female adolescent self-esteem, decision making, and contraceptive behavior has contributed to the knowledge base about female contraceptive behavior. Gaining further insight into these relationships will help healthcare professionals provide counseling and health care to female adolescents.

Interpret with caution: multicollinearity in multiple regression of cognitive data.

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Morrison, Catriona M

2003-08-01

Shibihara and Kondo in 2002 reported a reanalysis of the 1997 Kanji picture-naming data of Yamazaki, Ellis, Morrison, and Lambon-Ralph in which independent variables were highly correlated. Their addition of the variable visual familiarity altered the previously reported pattern of results, indicating that visual familiarity, but not age of acquisition, was important in predicting Kanji naming speed. The present paper argues that caution should be taken when drawing conclusions from multiple regression analyses in which the independent variables are so highly correlated, as such multicollinearity can lead to unreliable output.

Understanding logistic regression analysis.

Science.gov (United States)

Sperandei, Sandro

2014-01-01

Logistic regression is used to obtain odds ratio in the presence of more than one explanatory variable. The procedure is quite similar to multiple linear regression, with the exception that the response variable is binomial. The result is the impact of each variable on the odds ratio of the observed event of interest. The main advantage is to avoid confounding effects by analyzing the association of all variables together. In this article, we explain the logistic regression procedure using examples to make it as simple as possible. After definition of the technique, the basic interpretation of the results is highlighted and then some special issues are discussed.

The contribution of gender-role orientation, work factors and home stressors to psychological well-being and sickness absence in male- and female-dominated occupational groups.

Science.gov (United States)

Evans, Olga; Steptoe, Andrew

2002-02-01

The associations of work stress, types of work and gender-role orientation with psychological well-being and sickness absence were investigated in a questionnaire survey of 588 male and female nurses and 387 male and female accountants. We hypothesised that health might be impaired among women working in the male-dominated occupation (accountancy), and men in the female-dominated occupation (nursing), but that effects might be moderated by job strain (perceptions of high demand and low control), work and home hassles, and traditional male (instrumentality) and female (expressivity) psychological characteristics. Responses were analysed from 172 female and 61 male nurses, and from 53 female and 81 male commercial accountants. Female accountants were more likely than other groups to have high anxiety scores on the Hospital Anxiety and Depression Scales, while male nurses had the highest rates of sickness absence. Male nurses and female accountants also reported more work-related hassles than did female nurses and male accountants. Men and women in the same occupation did not differ in job strain or job social support, but nurses reported greater job strain than accountants, due to higher ratings of demands and lower skill utilisation. After adjusting for age, sex, occupation, paid work hours and a measure of social desirability bias, risk of elevated anxiety was independently associated with higher job strain, lower job social support, more work hassles, more domestic responsibility, lower instrumentality and higher expressivity. The association between sex and anxiety was no longer significant after instrumentality had been entered into the regression model. Sickness absence of more than three days over the past 12 months was independently associated with higher job strain, more work hassles, lower instrumentality and higher expressivity. The results suggest that when men and women occupy jobs in which they are in the cultural and numerical minority, there may be

Attractiveness of the female body: Preference for the average or the supernormal?

Directory of Open Access Journals (Sweden)

Marković Slobodan

2017-01-01

Full Text Available The main purpose of the present study was to contrast the two hypotheses of female body attractiveness. The first is the “preference-for-the average” hypothesis: the most attractive female body is the one that represents the average body proportions for a given population. The second is the “preference-for-the supernormal” hypothesis: according to the so-called “peak shift effect”, the most attractive female body is more feminine than the average. We investigated the preference for three female body characteristics: waist to hip ratio (WHR, buttocks and breasts. There were 456 participants of both genders. Using a program for computer animation (DAZ 3D three sets of stimuli were generated (WHR, buttocks and breasts. Each set included six stimuli ranked from the lowest to the highest femininity level. Participants were asked to choose the stimulus within each set which they found most attractive (task 1 and average (task 2. One group of participants judged the body parts that were presented in the global context (whole body, while the other group judged the stimuli in the local context (isolated body parts only. Analyses have shown that the most attractive WHR, buttocks and breasts are more feminine (meaning smaller for WHR and larger for breasts and buttocks than average ones, for both genders and in both presentation contexts. The effect of gender was obtained only for the most attractive breasts: males prefer larger breasts than females. Finally, most attractive and average WHR and breasts were less feminine in the local than in the global context. These results support the preference-for the supernormal hypothesis: all analyses have shown that both male and female participants preferred female body parts which are more feminine than those judged average. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 179033

Shift work parameters and disruption of diurnal cortisol production in female hospital employees.

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Hung, Eleanor Wai Man; Aronson, Kristan J; Leung, Michael; Day, Andrew; Tranmer, Joan

2016-01-01

Shift work is associated with an increased risk of cardiovascular diseases (CVD). Disruption of cortisol production is a potential underlying mechanism. This study explored the associations of diurnal quantity and pattern of cortisol production in relation to (1) current shift work status (exclusive day versus rotating days and nights), (2) years of past shift work and (3) parameters of rotating shift work (timing, length and intensity). Female hospital employees (160 day workers and 168 rotating shift workers) from southeastern Ontario, Canada, participated in a cross-sectional study. Participants completed a baseline questionnaire and measures of body height, weight, and waist circumference were taken. Midstream urine samples were collected over two separate 24-hour periods to measure creatinine-adjusted cortisol. Total diurnal cortisol production and pattern were described with two measures of the area under the curve. The effect of shift work on cortisol was modeled using multivariable linear regression analyses. Cortisol production in day workers and shift workers on their day shift were similar; however, shift workers on the night shift had flatter diurnal cortisol curves and produced less cortisol. This suggests that night work is associated with an acute attenuation of cortisol production.

A cohort study evaluating the implications of biology, weight status and socioeconomic level on global self-esteem competence among female African-American adolescents.

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Powell-Young, Yolanda M; Zabaleta, Jovanny; Velasco-Gonzalez, Cruz; Sothern, Melinda S

2013-07-01

The link between obesity and self-esteem among minority youth has received minimal empirical evaluation. This study aims to describe the magnitude of risk that body mass index, household income, and transitional age have on global self-esteem levels among African-American adolescents. These analyses were conducted on cross-sectional data obtained from 264 urban-dwelling African-American females between 14 and 18 years of age. Survey data on global self-esteem levels, transitory age, and socioeconomic levels were collected using self-administered questionnaires. Measured height and weight values were used to calculate and categorize weight status according to body mass index. Logistic regression models examined the probability of reporting less than average levels of global self-esteem. Adolescent African-American females residing in low-income households were 10 times more likely to report lower global self-esteem scores than those individuals from more affluent households (95% CI: 1.94, 60.19, p self-esteem among participants in this study. Household income appears to be the greatest predictor of global self-esteem levels. Further research in this area is needed to fully elucidate precursors for psychological health vulnerability and facilitate intervention development.

A Cohort Study Evaluating the Implications of Biology, Weight Status and Socioeconomic Level on Global Self-Esteem Competence Among Female African-American Adolescents

Science.gov (United States)

Powell-Young, Yolanda M.; Zabaleta, Jovanny; Velasco-Gonzalez, Cruz; Sothern, Melinda S.

2014-01-01

The link between obesity and self-esteem among minority youth has received minimal empirical evaluation. This study aims to describe the magnitude of risk that body mass index, household income, and transitional age have on global self-esteem levels among African-American adolescents. These analyses were conducted on cross-sectional data obtained from 264 urban-dwelling African-American females between 14 and 18 years of age. Survey data on global self-esteem levels, transitory age, and socioeconomic levels were collected using self-administered questionnaires. Measured height and weight values were used to calculate and categorize weight status according to body mass index. Logistic regression models examined the probability of reporting less than average levels of global self-esteem. Adolescent African-American females residing in low-income households were 10 times more likely to report lower global self-esteem scores than those individuals from more affluent households (95% CI: 1.94, 60.19, p self-esteem among participants in this study. Household income appears to be the greatest predictor of global self-esteem levels. Further research in this area is needed to fully elucidate precursors for psychological health vulnerability and facilitate intervention development. PMID:24218867

Kinematic gait analyses in healthy Golden Retrievers

OpenAIRE

Silva, Gabriela C.A.; Cardoso, Mariana Trés; Gaiad, Thais P.; Brolio, Marina P.; Oliveira, Vanessa C.; Assis Neto, Antonio; Martins, Daniele S.; Ambrósio, Carlos E.

2014-01-01

Kinematic analysis relates to the relative movement between rigid bodies and finds application in gait analysis and other body movements, interpretation of their data when there is change, determines the choice of treatment to be instituted. The objective of this study was to standardize the march of Dog Golden Retriever Healthy to assist in the diagnosis and treatment of musculoskeletal disorders. We used a kinematic analysis system to analyse the gait of seven dogs Golden Retriever, female,...

THE MEANING OF ALPHA FEMALE IN FEMALE LIBRARIAN: Building a Positive Image of Libraries through Female Librarians as Alpha Female

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Yunus Winoto

2017-08-01

Full Text Available MAKNA DIRI ALPHA FEMALE PADA PUSTAKAWAN PEREMPUAN: Membangun Citra Positif Perpustakaan Melalui Kiprah Pustakawan Perempuan Sebagai Alpha Female Abstract The profession of librarians is often associated with women. This can be justified if we refer to data and research results that have been done in several countries. However, many women who work in the library, this does not necessarily describe that library work is a simple and easy job. However, on the contrary, work in the field of library is increasingly complex and demands the competence and mastery of information technology. Moreover, the expectations of some users who demand a fast and quality service. Therefore to answer this problem required a female librarian who has the competence, intelligent and able to become a leader for his group and can show the characteristics as a professional. As for the description of people like this people call it with the term alpha female. With the birth of alpha female figures among female librarians is expected to change the positive image of librarians and library institutions. This is because the female alpha figure in the female librarian is a figure of women who are considered "perfect" are still rare today. Keywords: library, librarian, symbolic interaction, alpha female. Abstrak Profesi pustakawan kerapkali dikaitkan dengan kaum perempuan. Hal ini dapat dibenarkan jika kita merujuk pada data dan hasil riset yang telah dilakukan di beberapa negara. Namun demikian banyaknya kaum perempuan yang bekerja di perpustakaan, ini tidak serta merta menggambarkan bahwa pekerjaaan perpustakaan merupakan pekerjaan yang sederhana dan mudah. Namun justru sebaliknya pekerjaaan di bidang perpustakaan saat ini semakin kompleks dan menuntut kompetensi dan penguasaan teknologi informasi. Apalagi harapan sebagian pengguna yang menuntut suatu pelayanan ayang cepat dan berkualitas. Oleh karena demikian untuk menjawab permasalahan ini diperlukan sosok pustakawan

Minimax Regression Quantiles

DEFF Research Database (Denmark)

Bache, Stefan Holst

A new and alternative quantile regression estimator is developed and it is shown that the estimator is root n-consistent and asymptotically normal. The estimator is based on a minimax ‘deviance function’ and has asymptotically equivalent properties to the usual quantile regression estimator. It is......, however, a different and therefore new estimator. It allows for both linear- and nonlinear model specifications. A simple algorithm for computing the estimates is proposed. It seems to work quite well in practice but whether it has theoretical justification is still an open question....

Regression of Ophthalmopathic Exophthalmos in Graves' Disease After Total Thyroidectomy: a Prospective Study of a Surgical Series.

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Bhargav, P R K; Sabaretnam, M; Kumar, S Chandra; Zwalitha, S; Devi, N Vimala

2017-12-01

Autoimmune ophthalmopathy is one of the salient clinical features associated with Graves' disease. Exophthalmos is one of the commonest manifestations of Graves' associated ophthalmopathy. It is reported to regress after thyroidectomy favourably compared to radioiodine or antithyroid drug therapy. In this context, we present our experience based on a surgical series of Graves' disease. This is a prospective study of 15 patients of Graves' disease associated with ophthalmopathic exophthalmos. Preoperative and monthly postoperative evaluation of exophthalmos was done with Hertel's exophthalmometer, apart from documenting lid, extra-ocular muscle and orbital involvement. The minimum follow-up of the cohort was 12 months. The female to male ratio was 12:3 and the mean age of the subjects was 33.4 years (18-55). Exophthalmos was bilateral in 13 and unilateral in 2 patients. All the 15 patients underwent total thyroidectomy without any major morbidity. Exophthalmos regressed in 12 patients at a mean follow-up of 15.6 ± 6.4 months (14-38) and was static in 3. None of the cases had worsened ophthalmopathy at the final follow-up. Mean regression of exophthalmos was 2.1 mm (1-5). The regression was statistically significant at P value = 0.035. Surgery has a positive impact on the regression of ophthalmopathic exophthalmos associated with Graves' disease.

Regression with Sparse Approximations of Data

DEFF Research Database (Denmark)

Noorzad, Pardis; Sturm, Bob L.

2012-01-01

We propose sparse approximation weighted regression (SPARROW), a method for local estimation of the regression function that uses sparse approximation with a dictionary of measurements. SPARROW estimates the regression function at a point with a linear combination of a few regressands selected...... by a sparse approximation of the point in terms of the regressors. We show SPARROW can be considered a variant of \\(k\\)-nearest neighbors regression (\\(k\\)-NNR), and more generally, local polynomial kernel regression. Unlike \\(k\\)-NNR, however, SPARROW can adapt the number of regressors to use based...

Evaluating the Performance of Polynomial Regression Method with Different Parameters during Color Characterization

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Bangyong Sun

2014-01-01

Full Text Available The polynomial regression method is employed to calculate the relationship of device color space and CIE color space for color characterization, and the performance of different expressions with specific parameters is evaluated. Firstly, the polynomial equation for color conversion is established and the computation of polynomial coefficients is analysed. And then different forms of polynomial equations are used to calculate the RGB and CMYK’s CIE color values, while the corresponding color errors are compared. At last, an optimal polynomial expression is obtained by analysing several related parameters during color conversion, including polynomial numbers, the degree of polynomial terms, the selection of CIE visual spaces, and the linearization.

Weight preoccupation as a function of observed physical attractiveness: ethnic differences among normal-weight adolescent females.

Science.gov (United States)

Colabianchi, Natalie; Ievers-Landis, Carolyn E; Borawski, Elaine A

2006-09-01

To examine the association between observer ratings of physical attractiveness and weight preoccupation for female adolescents, and to explore any ethnic differences between Caucasian, African-American, and Hispanic females. Normal-weight female adolescents who had participated in the National Longitudinal Study of Adolescent Health in-home Wave II survey were included (n = 4,324). Physical attractiveness ratings were made in vivo by interviewers. Using logistic regression models stratified by ethnicity, the associations between observer-rated attractiveness and weight preoccupation were examined after controlling for demographics, measured body mass index (BMI) and psychosocial factors. Caucasian female adolescents perceived as being more attractive reported significantly greater weight preoccupation compared with those rated as being less attractive. Observed attractiveness did not relate to weight preoccupation among African-American or Hispanic youth when controlling for other factors. For Caucasian female adolescents, being perceived by others as more attractive may be a risk factor for disordered eating.

A simple approach to power and sample size calculations in logistic regression and Cox regression models.

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Vaeth, Michael; Skovlund, Eva

2004-06-15

For a given regression problem it is possible to identify a suitably defined equivalent two-sample problem such that the power or sample size obtained for the two-sample problem also applies to the regression problem. For a standard linear regression model the equivalent two-sample problem is easily identified, but for generalized linear models and for Cox regression models the situation is more complicated. An approximately equivalent two-sample problem may, however, also be identified here. In particular, we show that for logistic regression and Cox regression models the equivalent two-sample problem is obtained by selecting two equally sized samples for which the parameters differ by a value equal to the slope times twice the standard deviation of the independent variable and further requiring that the overall expected number of events is unchanged. In a simulation study we examine the validity of this approach to power calculations in logistic regression and Cox regression models. Several different covariate distributions are considered for selected values of the overall response probability and a range of alternatives. For the Cox regression model we consider both constant and non-constant hazard rates. The results show that in general the approach is remarkably accurate even in relatively small samples. Some discrepancies are, however, found in small samples with few events and a highly skewed covariate distribution. Comparison with results based on alternative methods for logistic regression models with a single continuous covariate indicates that the proposed method is at least as good as its competitors. The method is easy to implement and therefore provides a simple way to extend the range of problems that can be covered by the usual formulas for power and sample size determination. Copyright 2004 John Wiley & Sons, Ltd.

Clinico-biochemical factors to early predict biliary etiology of acute pancreatitis: age, female gender, and ALT.

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Zarnescu, N O; Costea, R; Zarnescu Vasiliu, E C; Neagu, S

2015-01-01

Background/ Aims: Despite the existence of an easy tool to diagnose biliary tract disease as an etiology for acute pancreatitis (AP), the sensitivity of abdominal ultrasound is around 80%, which can be even lower in certain conditions. We have retrospectively reviewed data of 146 patients admitted for acute pancreatitis between 1999 and 2013. Bivariate analysis for clinical and biochemical variables was performed with respect to etiology of AP (biliary versus non-biliary). Multivariate analysis was performed by using binary logistic regression. There were 87 males (59.6%) and 59 females (40.4%), with a median age of 51. The etiology of acute pancreatitis was biliary in 71 patients (48.6%). Bivariate analysis found the following as significant association (p=0.001) with biliary pancreatitis: older age, female gender, and elevated AST, ALT. A binary logistic regression analysis identified as predictor factors for biliary etiology of acute pancreatitis: age OR = 1.031 (95% CI 1.004 - 1.059, p = 0.024), sex (female) OR = 2.34 (95% CI 1.022 - 5.359, p = 0.044) and ALT OR = 1.004 (95% CI 1.001 - 1.007, p =0.004). The two clinical scores included the three variables (A.S.ALT scores) in categorical format were generated and then checked with the ROC curves (areas under curve are 0.768 and 0.778). Age, female gender, and elevated ALT can help identifying cases with biliary etiology of acute pancreatitis.

Genetic variation may explain why females are less susceptible to dental erosion.

Science.gov (United States)

Uhlen, Marte-Mari; Stenhagen, Kjersti R; Dizak, Piper M; Holme, Børge; Mulic, Aida; Tveit, Anne B; Vieira, Alexandre R

2016-10-01

Not all individuals at risk for dental erosion (DE) display erosive lesions. The prevalence of DE is higher among male subjects. The occurrence of DE may depend on more than just acidic challenge, with genetics possibly playing a role. The aim of this study was to investigate the association of enamel-formation genes with DE. One premolar and a saliva sample were collected from 90 individuals. Prepared teeth were immersed in 0.01 M HCl (pH 2.2), and enamel loss (μm) was measured using white light interferometry. DNA was extracted from saliva, and 15 single-nucleotide polymorphisms were analysed. Allele and genotype frequencies were related to the enamel loss of the specimens. Single-marker and haplotype analyses were performed using sex as a covariate. Mean enamel loss was higher for male donors than for female donors (P = 0.047). Significant associations were found between enamel loss and amelogenin, X-linked (AMELX), tuftelin 1 (TUFT1), and tuftelin-interacting protein 11 (TFIP11). Analyses showed significant associations between variation in enamel-formation genes and a lower susceptibility to DE in female subjects. The results indicate that susceptibility to DE is influenced by genetic variation, and may, in part, explain why some individuals are more susceptible than others to DE, including differences between female subjects and male subjects. © 2016 Eur J Oral Sci.

Testosterone-induced "Virilization" of Mesonephric Duct Remnants and Cervical Squamous Epithelium in Female-to-Male Transgenders: A Report of 3 Cases.

Science.gov (United States)

Singh, Kamaljeet; Sung, C James; Lawrence, W Dwayne; Quddus, M Ruhul

2017-07-01

Mesonephric ducts regress in genotypic females, leaving behind few remnants. These vestigial structures are often recognized in the mesosalpinx and paracervical regions. We report here 3 cases of female-to-male transgenders who underwent hysterectomy following testosterone treatment. Both female and male genital structures were identified on histologic examination. Although the morphologic appearances of the specimens were unremarkable, histologically 1 case revealed a well-formed fallopian tube as well as an epididymis and 2 cases showed prostate glands to be present in the cervical squamous epithelium.

Genetic evaluation of European quails by random regression models

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Flaviana Miranda Gonçalves

2012-09-01

Full Text Available The objective of this study was to compare different random regression models, defined from different classes of heterogeneity of variance combined with different Legendre polynomial orders for the estimate of (covariance of quails. The data came from 28,076 observations of 4,507 female meat quails of the LF1 lineage. Quail body weights were determined at birth and 1, 14, 21, 28, 35 and 42 days of age. Six different classes of residual variance were fitted to Legendre polynomial functions (orders ranging from 2 to 6 to determine which model had the best fit to describe the (covariance structures as a function of time. According to the evaluated criteria (AIC, BIC and LRT, the model with six classes of residual variances and of sixth-order Legendre polynomial was the best fit. The estimated additive genetic variance increased from birth to 28 days of age, and dropped slightly from 35 to 42 days. The heritability estimates decreased along the growth curve and changed from 0.51 (1 day to 0.16 (42 days. Animal genetic and permanent environmental correlation estimates between weights and age classes were always high and positive, except for birth weight. The sixth order Legendre polynomial, along with the residual variance divided into six classes was the best fit for the growth rate curve of meat quails; therefore, they should be considered for breeding evaluation processes by random regression models.

Psychological Gender and Emotional Intelligence in Youth Female Soccer Players

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Rutkowska Katarzyna

2015-09-01

Full Text Available Many sports (for instance soccer are stereotypically perceived as a male activity. Even so, more and more women decide to become competitive athletes. Since the theory of sport requires comprehensive explanations and the practice of sport needs clear guidelines, interdisciplinary studies into the nature of sport, including its psychological aspects, are necessary. Analysing the psychological profile of female soccer players, particularly those who are about to become professional athletes, can provide many interesting insights into the specific character of female youth sport and show where improvements can be made in athletic training programmes (especially in mental training. It is therefore important to study psychological gender that determines social behaviours and to analyse female athletes’ emotional intelligence. Emotional intelligence is defined as a set of emotional competencies that determine the effectiveness of human behaviours. Psychological gender and emotional intelligence have a significant effect on human adaptability and the efficiency of psychosocial functioning. This research was undertaken with the dual purpose of identifying the psychological gender and emotional intelligence of female soccer players. It involved 54 secondary-school girls, some of whom attended a sports class and others played on the Polish national team. The following tools were used to carry out the research: the Gender Assessment Inventory (IPP [This and the other acronyms derive from the Polish language]-developed by Kuczyńska and the Emotional Intelligence Questionnaire (INTE; created by Jaworowska and Matczak. As shown by the analysis of the results, most female soccer players in the study were androgynous and the level of their emotional intelligence was significantly higher than in other participants. This also seems to point to their significantly greater adaptability. At the same time, the level of emotional intelligence in many players was

Psychological Gender and Emotional Intelligence in Youth Female Soccer Players.

Science.gov (United States)

Rutkowska, Katarzyna; Bergier, Józef

2015-09-29

Many sports (for instance soccer) are stereotypically perceived as a male activity. Even so, more and more women decide to become competitive athletes. Since the theory of sport requires comprehensive explanations and the practice of sport needs clear guidelines, interdisciplinary studies into the nature of sport, including its psychological aspects, are necessary. Analysing the psychological profile of female soccer players, particularly those who are about to become professional athletes, can provide many interesting insights into the specific character of female youth sport and show where improvements can be made in athletic training programmes (especially in mental training). It is therefore important to study psychological gender that determines social behaviours and to analyse female athletes' emotional intelligence. Emotional intelligence is defined as a set of emotional competencies that determine the effectiveness of human behaviours. Psychological gender and emotional intelligence have a significant effect on human adaptability and the efficiency of psychosocial functioning. This research was undertaken with the dual purpose of identifying the psychological gender and emotional intelligence of female soccer players. It involved 54 secondary-school girls, some of whom attended a sports class and others played on the Polish national team. The following tools were used to carry out the research: the Gender Assessment Inventory (IPP [This and the other acronyms derive from the Polish language]-developed by Kuczyńska) and the Emotional Intelligence Questionnaire (INTE; created by Jaworowska and Matczak). As shown by the analysis of the results, most female soccer players in the study were androgynous and the level of their emotional intelligence was significantly higher than in other participants. This also seems to point to their significantly greater adaptability. At the same time, the level of emotional intelligence in many players was average or low

Regression tree analysis for predicting body weight of Nigerian Muscovy duck (Cairina moschata

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Oguntunji Abel Olusegun

2017-01-01

Full Text Available Morphometric parameters and their indices are central to the understanding of the type and function of livestock. The present study was conducted to predict body weight (BWT of adult Nigerian Muscovy ducks from nine (9 morphometric parameters and seven (7 body indices and also to identify the most important predictor of BWT among them using regression tree analysis (RTA. The experimental birds comprised of 1,020 adult male and female Nigerian Muscovy ducks randomly sampled in Rain Forest (203, Guinea Savanna (298 and Derived Savanna (519 agro-ecological zones. Result of RTA revealed that compactness; body girth and massiveness were the most important independent variables in predicting BWT and were used in constructing RT. The combined effect of the three predictors was very high and explained 91.00% of the observed variation of the target variable (BWT. The optimal regression tree suggested that Muscovy ducks with compactness >5.765 would be fleshy and have highest BWT. The result of the present study could be exploited by animal breeders and breeding companies in selection and improvement of BWT of Muscovy ducks.

Development of Super-Ensemble techniques for ocean analyses: the Mediterranean Sea case

Science.gov (United States)

Pistoia, Jenny; Pinardi, Nadia; Oddo, Paolo; Collins, Matthew; Korres, Gerasimos; Drillet, Yann

2017-04-01

Short-term ocean analyses for Sea Surface Temperature SST in the Mediterranean Sea can be improved by a statistical post-processing technique, called super-ensemble. This technique consists in a multi-linear regression algorithm applied to a Multi-Physics Multi-Model Super-Ensemble (MMSE) dataset, a collection of different operational forecasting analyses together with ad-hoc simulations produced by modifying selected numerical model parameterizations. A new linear regression algorithm based on Empirical Orthogonal Function filtering techniques is capable to prevent overfitting problems, even if best performances are achieved when we add correlation to the super-ensemble structure using a simple spatial filter applied after the linear regression. Our outcomes show that super-ensemble performances depend on the selection of an unbiased operator and the length of the learning period, but the quality of the generating MMSE dataset has the largest impact on the MMSE analysis Root Mean Square Error (RMSE) evaluated with respect to observed satellite SST. Lower RMSE analysis estimates result from the following choices: 15 days training period, an overconfident MMSE dataset (a subset with the higher quality ensemble members), and the least square algorithm being filtered a posteriori.

Risky sexual behavior among rural female adolescents in Malaysia: a limited role of protective factors.

Science.gov (United States)

Ahmadian, Maryam; Hamsan, Hanina H; Abdullah, Haslinda; Samah, Asnarulkhadi Abu; Noor, Amna Md

2014-03-23

This paper presents the findings of a cross-sectional survey on the risk and protective factors of premarital sexual behavior among rural female adolescents in Peninsular Malaysia. We investigated data on 770 female respondents aged 13-17 years in rural areas to identify predictive factors for premarital sexual intercourse. Data were analyzed using bivariate and multivariate regression. Specific socio-demographic factors, psychological and family domains, peer delinquency, and knowledge and attitudes about sexuality were considered in risky sexual behaviors in rural Malay girls. The effects of other covariates for premarital sexual intercourse were controlled by logistic regression model. Of the 770 rural female students, about 3.2% of respondents reported experience of sexual intercourse in the past three months. Out of those sexually active girls, 36% were 17 years old and 20% stated having sexual intercourse with more than one partner, and 72% did not use contraception during the most recent sexual intercourse. Midnight activities, peer-sexual disorder, self-evaluation, and attitude toward sexual health were significant predictors of sexual intercourse in rural girls in Malaysia. The finding highlights the impact of psychological factors and peer group influences on the challenges of premarital sexual behavior among rural girls and the notion of school-based sexual health education for adolescents. This study triggers other researchers take into account a comprehensive view of protective factors operating in adolescents' risky sexual behaviors in Asian culture seeing that family domain variables, unexpectedly, exerted no predicting influence on sexually active female teens in rural areas in Malaysia.

Risky Sexual Behavior among Rural Female Adolescents in Malaysia: A Limited Role of Protective Factors

Science.gov (United States)

Ahmadian, Maryam; Hamsan, Hanina H.; Abdullah, Haslinda; Samah, Asnarulkhadi Abu; Noor, Amna Md

2014-01-01

Purpose: This paper presents the findings of a cross-sectional survey on the risk and protective factors of premarital sexual behavior among rural female adolescents in Peninsular Malaysia. Methods: We investigated data on 770 female respondents aged 13-17 years in rural areas to identify predictive factors for premarital sexual intercourse. Data were analyzed using bivariate and multivariate regression. Specific socio-demographic factors, psychological and family domains, peer delinquency, and knowledge and attitudes about sexuality were considered in risky sexual behaviors in rural Malay girls. The effects of other covariates for premarital sexual intercourse were controlled by logistic regression model. Results: Of the 770 rural female students, about 3.2% of respondents reported experience of sexual intercourse in the past three months. Out of those sexually active girls, 36% were 17 years old and 20% stated having sexual intercourse with more than one partner, and 72% did not use contraception during the most recent sexual intercourse. Midnight activities, peer-sexual disorder, self-evaluation, and attitude toward sexual health were significant predictors of sexual intercourse in rural girls in Malaysia. Conclusion: The finding highlights the impact of psychological factors and peer group influences on the challenges of premarital sexual behavior among rural girls and the notion of school-based sexual health education for adolescents. This study triggers other researchers take into account a comprehensive view of protective factors operating in adolescents’ risky sexual behaviors in Asian culture seeing that family domain variables, unexpectedly, exerted no predicting influence on sexually active female teens in rural areas in Malaysia. PMID:24762359

Post-processing through linear regression

Science.gov (United States)

van Schaeybroeck, B.; Vannitsem, S.

2011-03-01

Various post-processing techniques are compared for both deterministic and ensemble forecasts, all based on linear regression between forecast data and observations. In order to evaluate the quality of the regression methods, three criteria are proposed, related to the effective correction of forecast error, the optimal variability of the corrected forecast and multicollinearity. The regression schemes under consideration include the ordinary least-square (OLS) method, a new time-dependent Tikhonov regularization (TDTR) method, the total least-square method, a new geometric-mean regression (GM), a recently introduced error-in-variables (EVMOS) method and, finally, a "best member" OLS method. The advantages and drawbacks of each method are clarified. These techniques are applied in the context of the 63 Lorenz system, whose model version is affected by both initial condition and model errors. For short forecast lead times, the number and choice of predictors plays an important role. Contrarily to the other techniques, GM degrades when the number of predictors increases. At intermediate lead times, linear regression is unable to provide corrections to the forecast and can sometimes degrade the performance (GM and the best member OLS with noise). At long lead times the regression schemes (EVMOS, TDTR) which yield the correct variability and the largest correlation between ensemble error and spread, should be preferred.

Prevalence and Correlates of Non-Disclosure of HIV Serostatus to Sex partners among HIV-Infected Female Sex Workers and HIV-infected Male Clients of Female Sex Workers in India

Science.gov (United States)

Raj, Anita; Mahapatra, Bidhubhusan; Cheng, Debbie M.; Coleman, Sharon; Bridden, Carly; Battala, Madhusudana; Silverman, Jay G.; Pardeshi, Manoj H.; Samet, Jeffrey H.

2013-01-01

This study examines non-disclosure of HIV serostatus to sex partners among HIV-infected adults involved with transactional sex in Mumbai, India. Surveys were conducted with HIV-infected female sex workers (n = 211) and infected male clients (n = 205) regarding HIV knowledge, awareness of sex partners’ HIV serostatus, alcohol use, transactional sex involvement post-HIV diagnosis and non-disclosure of HIV serostatus. Gender-stratified multiple logistic regression models were used for analysis. Non-disclosure of one’s serostatus to all sex partners was reported by almost three-fifths of females and two-fifths of males. Predictors of non-disclosure included lack of correct knowledge about HIV and no knowledge of sex partners’ HIV serostatus. Among females, recent alcohol consumption also predicted non-disclosure. Among males, 10 + paid sexual partners in the year following HIV diagnosis predicted non-disclosure. Secondary HIV prevention efforts in India require greater focus on HIV disclosure communication and integrated alcohol and sexual risk reduction. PMID:22810892

Hopelessness as a Predictor of Suicide Ideation in Depressed Male and Female Adolescent Youth.

Science.gov (United States)

Wolfe, Kristin L; Nakonezny, Paul A; Owen, Victoria J; Rial, Katherine V; Moorehead, Alexandra P; Kennard, Beth D; Emslie, Graham J

2017-12-21

We examined hopelessness as a predictor of suicide ideation in depressed youth after acute medication treatment. A total of 158 depressed adolescents were administered the Children's Depression Rating Scale-Revised (CDRS-R) and Columbia Suicide Severity Rating Scale (C-SSRS) as part of a larger battery at baseline and at weekly visits across 6 weeks of acute fluoxetine treatment. The Beck Hopelessness Scale (BHS) was administered at baseline and week 6. A negative binomial regression model via a generalized estimating equation analysis of repeated measures was used to estimate suicide ideation over the 6 weeks of acute treatment from baseline measure of hopelessness. Depression severity and gender were included as covariates in the model. The negative binomial analysis was also conducted separately for the sample of males and females (in a gender-stratified analysis). Mean CDRS-R total scores were 60.30 ± 8.93 at baseline and 34.65 ± 10.41 at week 6. Mean baseline and week 6 BHS scores were 9.57 ± 5.51 and 5.59 ± 5.38, respectively. Per the C-SSRS, 43.04% and 83.54% reported having no suicide ideation at baseline and at week 6, respectively. The analyses revealed that baseline hopelessness was positively related to suicide ideation over treatment (p = .0027), independent of changes in depression severity. This significant finding persisted only for females (p = .0024). These results indicate the importance of early identification of hopelessness. © 2017 The American Association of Suicidology.

Single-electron multiplication statistics as a combination of Poissonian pulse height distributions using constraint regression methods

International Nuclear Information System (INIS)

Ballini, J.-P.; Cazes, P.; Turpin, P.-Y.

1976-01-01

Analysing the histogram of anode pulse amplitudes allows a discussion of the hypothesis that has been proposed to account for the statistical processes of secondary multiplication in a photomultiplier. In an earlier work, good agreement was obtained between experimental and reconstructed spectra, assuming a first dynode distribution including two Poisson distributions of distinct mean values. This first approximation led to a search for a method which could give the weights of several Poisson distributions of distinct mean values. Three methods have been briefly exposed: classical linear regression, constraint regression (d'Esopo's method), and regression on variables subject to error. The use of these methods gives an approach of the frequency function which represents the dispersion of the punctual mean gain around the whole first dynode mean gain value. Comparison between this function and the one employed in Polya distribution allows the statement that the latter is inadequate to describe the statistical process of secondary multiplication. Numerous spectra obtained with two kinds of photomultiplier working under different physical conditions have been analysed. Then two points are discussed: - Does the frequency function represent the dynode structure and the interdynode collection process. - Is the model (the multiplication process of all dynodes but the first one, is Poissonian) valid whatever the photomultiplier and the utilization conditions. (Auth.)

Measurement of Uranium in Blood-Plasma of Bavarian Females

International Nuclear Information System (INIS)

Chaudhri, M.A.; Watling, R.J.

2011-01-01

It has recently been reported that the water supply in some parts of Bavaria (Germany) contains Uranium. In order to study its effects we have determined the concentrations of U in the blood plasma of 25 females. All the females came from Bavaria and were not on any medication. Blood samples were drawn from a superficial arm vein, centrifuged and plasma extracted. The plasma samples were freeze-dried and analysed in our Analytical Laboratory in Perth, Western Australia by using the technique of ICP-MS. The U contents found varied from less than 0.1 to 8.2 ppb (6.6 ng/L to 543 ng/L)

Regression modeling methods, theory, and computation with SAS

CERN Document Server

Panik, Michael

2009-01-01

Regression Modeling: Methods, Theory, and Computation with SAS provides an introduction to a diverse assortment of regression techniques using SAS to solve a wide variety of regression problems. The author fully documents the SAS programs and thoroughly explains the output produced by the programs.The text presents the popular ordinary least squares (OLS) approach before introducing many alternative regression methods. It covers nonparametric regression, logistic regression (including Poisson regression), Bayesian regression, robust regression, fuzzy regression, random coefficients regression,

Semiparametric regression during 2003–2007

KAUST Repository

Ruppert, David; Wand, M.P.; Carroll, Raymond J.

2009-01-01

Semiparametric regression is a fusion between parametric regression and nonparametric regression that integrates low-rank penalized splines, mixed model and hierarchical Bayesian methodology – thus allowing more streamlined handling of longitudinal and spatial correlation. We review progress in the field over the five-year period between 2003 and 2007. We find semiparametric regression to be a vibrant field with substantial involvement and activity, continual enhancement and widespread application.

Unbalanced Regressions and the Predictive Equation

DEFF Research Database (Denmark)

Osterrieder, Daniela; Ventosa-Santaulària, Daniel; Vera-Valdés, J. Eduardo

Predictive return regressions with persistent regressors are typically plagued by (asymptotically) biased/inconsistent estimates of the slope, non-standard or potentially even spurious statistical inference, and regression unbalancedness. We alleviate the problem of unbalancedness in the theoreti......Predictive return regressions with persistent regressors are typically plagued by (asymptotically) biased/inconsistent estimates of the slope, non-standard or potentially even spurious statistical inference, and regression unbalancedness. We alleviate the problem of unbalancedness...

Original article for BMC Infectious Diseases What is the potential for bisexual men in China to act as a bridge of HIV transmission to the female population? Behavioural evidence from a systematic review and meta-analysis

Directory of Open Access Journals (Sweden)

Zhang Lei

2011-09-01

Full Text Available Abstract Background HIV prevalence among men who have sex with men (MSM in China has rapidly increased in recent years. It is suggested that MSM could be a potential bridge of HIV transmission to the general female population. We investigated the bisexual behaviour of MSM in China through systematic review and meta-analysis. Methods We conducted a systematic review and meta-analyses on published peer-reviewed Chinese and English literature during 2001-2010 according to the PRISMA guidelines. Marital status and sexual behavioural indicators of MSM were presented graphically using forest plots. The pooled effect rates with 95% confidence intervals were also calculated. Meta-regression analyses were performed to examine the factors associated with high heterogeneities across the studies. Results Forty-three eligible articles (11 in English and 32 in Chinese were identified. Our results showed that 17.0% (95% CI: 15.1-19.1% of MSM in China are currently married to a woman and 26.3% (95% CI: 23.6-29.1% of MSM had female sexual partners in the last six months. The pooled estimates for condom use rate between MSM and female sex partners was 41.4% (95% CI: 35.5-47.5% at the last sex act; and 25.6% (95% CI: 23.0-28.4% in the last six months. The consistent condom use rates with regular, non-commercial, casual and commercial female sex partners in the last six months were 23.3% (95% CI: 11.25-42.1%, 39.0% (95% CI: 28.8-50.3% and 55.8% (95% CI: 41.4-69.4%, respectively. Conclusions A substantial proportion of Chinese MSM is currently married or had sexual relations with a female in the past six months. In addition, low condom usage was common between married MSM and their wives, hence posing a higher risk of transmitting HIV. Harm-reduction programs targeting married MSM and their female partners are necessary to curb the further spread of HIV infection to the general female population.

Comparison of multinomial logistic regression and logistic regression: which is more efficient in allocating land use?

Science.gov (United States)

Lin, Yingzhi; Deng, Xiangzheng; Li, Xing; Ma, Enjun

2014-12-01

Spatially explicit simulation of land use change is the basis for estimating the effects of land use and cover change on energy fluxes, ecology and the environment. At the pixel level, logistic regression is one of the most common approaches used in spatially explicit land use allocation models to determine the relationship between land use and its causal factors in driving land use change, and thereby to evaluate land use suitability. However, these models have a drawback in that they do not determine/allocate land use based on the direct relationship between land use change and its driving factors. Consequently, a multinomial logistic regression method was introduced to address this flaw, and thereby, judge the suitability of a type of land use in any given pixel in a case study area of the Jiangxi Province, China. A comparison of the two regression methods indicated that the proportion of correctly allocated pixels using multinomial logistic regression was 92.98%, which was 8.47% higher than that obtained using logistic regression. Paired t-test results also showed that pixels were more clearly distinguished by multinomial logistic regression than by logistic regression. In conclusion, multinomial logistic regression is a more efficient and accurate method for the spatial allocation of land use changes. The application of this method in future land use change studies may improve the accuracy of predicting the effects of land use and cover change on energy fluxes, ecology, and environment.

Mortality among female workers at a thorium-processing plant

International Nuclear Information System (INIS)

Liu, Zhiyuan; Lee, Tze-San.

1994-01-01

The mortality patterns among a cohort of 677 female workers at a thorium-processing plant are reported for the period from 1940 to 1982. Of the 677 women, 165 were reported dead; 459 were still alive; and 53 (7.8%) were lost to follow-up. The standardized mortality ratios from all causes (0.74), all cancers (0.53), and circulatory diseases (0.66) were significantly below those for the general US population. In this cohort, 5 deaths due to lung cancer and 1 death from leukemia were observed, with 4.53 and 1.69 deaths expected, respectively. No deaths from cancer of the liver, pancreas, or bone were observed. Poisson regression analysis was used for an internal comparison within the cohort. The results of the Poisson regression analysis showed no significant effect on mortality rates of all causes and cancers from the study factors, including job classification, duration of employment, and time since first employment

Adjusting for Confounding in Early Postlaunch Settings: Going Beyond Logistic Regression Models.

Science.gov (United States)

Schmidt, Amand F; Klungel, Olaf H; Groenwold, Rolf H H

2016-01-01

Postlaunch data on medical treatments can be analyzed to explore adverse events or relative effectiveness in real-life settings. These analyses are often complicated by the number of potential confounders and the possibility of model misspecification. We conducted a simulation study to compare the performance of logistic regression, propensity score, disease risk score, and stabilized inverse probability weighting methods to adjust for confounding. Model misspecification was induced in the independent derivation dataset. We evaluated performance using relative bias confidence interval coverage of the true effect, among other metrics. At low events per coefficient (1.0 and 0.5), the logistic regression estimates had a large relative bias (greater than -100%). Bias of the disease risk score estimates was at most 13.48% and 18.83%. For the propensity score model, this was 8.74% and >100%, respectively. At events per coefficient of 1.0 and 0.5, inverse probability weighting frequently failed or reduced to a crude regression, resulting in biases of -8.49% and 24.55%. Coverage of logistic regression estimates became less than the nominal level at events per coefficient ≤5. For the disease risk score, inverse probability weighting, and propensity score, coverage became less than nominal at events per coefficient ≤2.5, ≤1.0, and ≤1.0, respectively. Bias of misspecified disease risk score models was 16.55%. In settings with low events/exposed subjects per coefficient, disease risk score methods can be useful alternatives to logistic regression models, especially when propensity score models cannot be used. Despite better performance of disease risk score methods than logistic regression and propensity score models in small events per coefficient settings, bias, and coverage still deviated from nominal.

Interpretation of commonly used statistical regression models.

Science.gov (United States)

Kasza, Jessica; Wolfe, Rory

2014-01-01

A review of some regression models commonly used in respiratory health applications is provided in this article. Simple linear regression, multiple linear regression, logistic regression and ordinal logistic regression are considered. The focus of this article is on the interpretation of the regression coefficients of each model, which are illustrated through the application of these models to a respiratory health research study. © 2013 The Authors. Respirology © 2013 Asian Pacific Society of Respirology.

Bone mineral density and nutritional indices in adolescent females with recently diagnosed anorexia

International Nuclear Information System (INIS)

Wong, J.C.H.; Lewindon, P.J.; Mortimer, R.; Sheperd, R.W.; Royal Children's Hospital, Brisbane, QLD

1999-01-01

Full text: Osteopenia/osteoporosis and fractures have been shown to occur with anorexia nervosa (AN). This study evaluated adolescent females diagnosed with AN less than 12 months previously to determine the presence of any significant bone mass reduction at this early stage of diagnosis and to evaluate the correlation between total body (TB) and lumbar spine (LS) bone mineral densities (BMD) and bone mineral content (BMC), and nutritional indices (body weight, body mass index (BMI), lean mass, fat mass and percentage fat). The subjects were 22 adolescent females aged 12-17 years (mean= 14.3 years) diagnosed with AN less than 12 months earlier (range 2.5-11 months; mean = 6.7 months). They had bone density measurements of the TB and LS using a Lunar DPX-L densitometer. Comparison was made with values of age-matched controls in the Lunar normative database. Although there was a tendency towards low TB and LS bone mass, these changes were not statistically significant. Bivariate analyses showed significant correlation between TB BMD and lean mass (P < 0.001) and weight (P < 0.001) and between TB BMC and lean mass (P < 0.001) and weight (P < 0.01). There was similar significant correlation between LS BMD and lean mass (P < 0.01) and weight (P<0.01), and between LS BMC and lean mass (P < 0.01) and weight (P < 0.01). With stepwise regression analysis, only lean mass remained significantly correlated with TB BMD and BMC and LS BMD and BMC. There was no longer any significant correlation with weight. In this study, the weight percentile was found to be correlated highly with the LS BMD Z-score (P < 0.01). Therefore, during adolescence, the lean mass in particular, but also body weight, are good indicators of bone densities. Adolescent females do not appear to show bone mass reduction in the early stages of diagnosis of anorexia nervosa. This suggests early intervention may preserve bone gain and attainment of normal peak bone mass

Male breast cancer: a nation-wide population-based comparison with female breast cancer.

Science.gov (United States)

Lautrup, Marianne D; Thorup, Signe S; Jensen, Vibeke; Bokmand, Susanne; Haugaard, Karen; Hoejris, Inger; Jylling, Anne-Marie B; Joernsgaard, Hjoerdis; Lelkaitis, Giedrius; Oldenburg, Mette H; Qvamme, Gro M; Soee, Katrine; Christiansen, Peer

2018-05-01

Describe prognostic parameters of Danish male breast cancer patients (MBCP) diagnosed from 1980-2009. Determine all-cause mortality compared to the general male population and analyze survival/mortality compared with Danish female breast cancer patients (FBCP) in the same period. The MBCP cohort was defined from three national registers. Data was extracted from medical journals. Data for FBCP is from the DBCG database. Overall survival (OS) was quantified by Kaplan-Meier estimates. Standardized mortality ratios (SMRs) were calculated based on mortality rate among patients relative to the mortality rate in the general population. The association between SMR and risk factors were analyzed in univariate and multivariable Poisson regression models. Separate models for each gender were used for the analyses. We found a marked difference in OS for the two genders. For the total population of MBCP, 5- and 10-year survivals were 55.1% and 31.7%, respectively. For FBCP, the corresponding figures were 76.8% and 59.3%. Median age at diagnosis for FBCP was 61 years and 70 years for MBCP. By applying SMR, the difference in mortality between genders equalized and showed pronounced age-dependency. For males <40 years, SMR was 9.43 and for females 19.56 compared to SMR for males 80 + years (0.95) and females 80 + years (0.89). During the period 1980-2009, the risk of dying gradually decreased for FBCP (p < .0001). The risk 1980-1984 was 35% higher than 2005-2009 (RR 1.35). Although the risk of dying for MBCP was also lowest in 2005-2009, there was no clear tendency (p = .1439). The risk was highest in 1990-1994 (RR =2.48). We found better OS for FBCP than for MBCP. But SMR showed similar mortality rate for the two genders, except for very young FBCP, who had higher SMR. Furthermore, significantly improved survival over time for FBCP was observed, with no clear tendency for MBCP.

Linear regression

CERN Document Server

Olive, David J

2017-01-01

This text covers both multiple linear regression and some experimental design models. The text uses the response plot to visualize the model and to detect outliers, does not assume that the error distribution has a known parametric distribution, develops prediction intervals that work when the error distribution is unknown, suggests bootstrap hypothesis tests that may be useful for inference after variable selection, and develops prediction regions and large sample theory for the multivariate linear regression model that has m response variables. A relationship between multivariate prediction regions and confidence regions provides a simple way to bootstrap confidence regions. These confidence regions often provide a practical method for testing hypotheses. There is also a chapter on generalized linear models and generalized additive models. There are many R functions to produce response and residual plots, to simulate prediction intervals and hypothesis tests, to detect outliers, and to choose response trans...

Regression modeling of ground-water flow

Science.gov (United States)

Cooley, R.L.; Naff, R.L.

1985-01-01

Nonlinear multiple regression methods are developed to model and analyze groundwater flow systems. Complete descriptions of regression methodology as applied to groundwater flow models allow scientists and engineers engaged in flow modeling to apply the methods to a wide range of problems. Organization of the text proceeds from an introduction that discusses the general topic of groundwater flow modeling, to a review of basic statistics necessary to properly apply regression techniques, and then to the main topic: exposition and use of linear and nonlinear regression to model groundwater flow. Statistical procedures are given to analyze and use the regression models. A number of exercises and answers are included to exercise the student on nearly all the methods that are presented for modeling and statistical analysis. Three computer programs implement the more complex methods. These three are a general two-dimensional, steady-state regression model for flow in an anisotropic, heterogeneous porous medium, a program to calculate a measure of model nonlinearity with respect to the regression parameters, and a program to analyze model errors in computed dependent variables such as hydraulic head. (USGS)

Extending the linear model with R generalized linear, mixed effects and nonparametric regression models

CERN Document Server

Faraway, Julian J

2005-01-01

Linear models are central to the practice of statistics and form the foundation of a vast range of statistical methodologies. Julian J. Faraway''s critically acclaimed Linear Models with R examined regression and analysis of variance, demonstrated the different methods available, and showed in which situations each one applies. Following in those footsteps, Extending the Linear Model with R surveys the techniques that grow from the regression model, presenting three extensions to that framework: generalized linear models (GLMs), mixed effect models, and nonparametric regression models. The author''s treatment is thoroughly modern and covers topics that include GLM diagnostics, generalized linear mixed models, trees, and even the use of neural networks in statistics. To demonstrate the interplay of theory and practice, throughout the book the author weaves the use of the R software environment to analyze the data of real examples, providing all of the R commands necessary to reproduce the analyses. All of the ...

Physical Activity across Frailty Phenotypes in Females with Parkinson’s Disease

Directory of Open Access Journals (Sweden)

Kaitlyn P. Roland

2012-01-01

Full Text Available Females with Parkinson’s disease (PD are vulnerable to frailty. PD eventually leads to decreased physical activity, an indicator of frailty. We speculate PD results in frailty through reduced physical activity. Objective. Determine the contribution of physical activity on frailty in PD (n=15, 65 ± 9 years and non-PD (n=15, 73 ± 14 years females. Methods. Frailty phenotype (nonfrail/prefrail/frail was categorized and 8 hours of physical activity was measured using accelerometer, global positioning system, and self-report. Two-way ANCOVA (age as covariate was used to compare physical activity between disease and frailty phenotypes. Spearman correlation assessed relationships, and linear regression determined associations with frailty. Results. Nonfrail recorded more physical activity (intensity, counts, self-report compared with frail. Self-reported physical activity was greater in PD than non-PD. In non-PD, step counts, light physical activity time, sedentary time, and self-reported physical activity were related to frailty (R=0.91. In PD, only carbidopa-levodopa dose was related to frailty (r=0.61. Conclusion. Physical activity influences frailty in females without PD. In PD females, disease management may be a better indicator of frailty than physical activity. Further investigation into how PD associated factors contribute to frailty is warranted.

Verbal fluency in male and female schizophrenia patients: Different patterns of association with processing speed, working memory span, and clinical symptoms.

Science.gov (United States)

Brébion, Gildas; Stephan-Otto, Christian; Ochoa, Susana; Nieto, Lourdes; Contel, Montserrat; Usall, Judith

2018-01-01

Decreased processing speed in schizophrenia patients has been identified as a major impairment factor in various neuropsychological domains. Working memory span has been found to be involved in several deep or effortful cognitive processes. We investigated the impact that these 2 cognitive functions may have on phonological and semantic fluency in schizophrenia patients and healthy participants. Fifty-five patients with schizophrenia and 60 healthy participants were administered a neuropsychological battery including phonological and semantic fluency, working memory, and cognitive and motor speed. Regression analyses revealed that motor speed was related to phonological fluency in female patients, whereas cognitive speed was related to semantic fluency in male patients. In addition, working memory span was related to verbal fluency in women from both the patient and the healthy control groups. Decreased processing speed, but not decreased working memory span, accounted for the verbal fluency deficit in patients. Verbal fluency was inversely related to attention deficit in female patients and to negative symptoms in male patients. Decreased processing speed may be the main factor in verbal fluency impairment of patients. Further, the cognitive and clinical predictors of verbal fluency efficiency are different in men and women. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

The shady past of female boxers – what case studies in the USA reveal

DEFF Research Database (Denmark)

Pfister, Gertrud Ursula; Gems, Gerald

2017-01-01

This study attempts to rectify the invisibility of female boxers and to narrow a research gap by examining the careers of four prominent female champions who managed to excel in the sport despite the social, psychological and physical restrictions imposed by the gender order of American society...... in the nineteenth century. The little studied roles of female boxers present some historiographical issues detailed in the study, which examines and analyses the social construction of gender, and the rejection of prescribed roles by the female boxers, who used the vaudeville and theatrical stages to negotiate...... a transition in gender roles, particularly the notion of females as a ‘weaker sex’. The lives of such courageous women presented an incremental change in the restrictive practices of society, leading to a greater measure of female liberation in succeeding years....

[Familial characteristics and self-perceived health among female and male primary care physicians in Andalusia (Spain)].

Science.gov (United States)

Delgado, Ana; Saletti-Cuesta, Lorena; López-Fernández, Luis Andrés; Toro-Cárdenas, Silvia

2013-01-01

To determine the relationships between a group of professional and family characteristics and the components of physical and mental health in female and male primary care physicians working in health centers in Andalusia (Spain). A descriptive, cross-sectional, multicenter study was performed. The population consisted of urban health centers in Andalusia and their physicians. The sample comprised 88 health centers and 500 physicians. Measurements consisted of sex, age, professional characteristics (postgraduate training in family medicine, position of health center manager, accreditation as a residents' tutor, and workload based on patient quota and the mean number of patients/day); family responsibilities, defined by two dimensions of the family-work relationship (support overload-family support deficit and family-work conflict); and perceived physical and mental health. The data source was a self-administered questionnaire sent by surface mail. Multiple regression analyses were performed for physical and mental health for the whole sample and by gender. Responses were obtained from 368 physicians (73.6%). Mental health was worse in female physicians than in male physicians; no differences were found between genders in physical health. The family-work conflict was associated with physical and mental health in physicians of both genders. Physical health deteriorated with increasing age in both genders, improved in the female tutors of residents, and decreased with increasing family-work conflict in male physicians. Mental health decreased with increasing housework on the weekends and with family-work conflict in both genders. In male physicians, mental health deteriorated with postgraduate training in family medicine and improved if they were health center managers. Workload and professional characteristics have little relationship with the health of primary care physicians. Family characteristics play a greater role. Copyright © 2012 SESPAS. Published by Elsevier

Regression analysis utilizing subjective evaluation of emotional experience in PET studies on emotions.

Science.gov (United States)

Aalto, Sargo; Wallius, Esa; Näätänen, Petri; Hiltunen, Jaana; Metsähonkala, Liisa; Sipilä, Hannu; Karlsson, Hasse

2005-09-01

A methodological study on subject-specific regression analysis (SSRA) exploring the correlation between the neural response and the subjective evaluation of emotional experience in eleven healthy females is presented. The target emotions, i.e., amusement and sadness, were induced using validated film clips, regional cerebral blood flow (rCBF) was measured using positron emission tomography (PET), and the subjective intensity of the emotional experience during the PET scanning was measured using a category ratio (CR-10) scale. Reliability analysis of the rating data indicated that the subjects rated the intensity of their emotional experience fairly consistently on the CR-10 scale (Cronbach alphas 0.70-0.97). A two-phase random-effects analysis was performed to ensure the generalizability and inter-study comparability of the SSRA results. Random-effects SSRAs using Statistical non-Parametric Mapping 99 (SnPM99) showed that rCBF correlated with the self-rated intensity of the emotional experience mainly in the brain regions that were identified in the random-effects subtraction analyses using the same imaging data. Our results give preliminary evidence of a linear association between the neural responses related to amusement and sadness and the self-evaluated intensity of the emotional experience in several regions involved in the emotional response. SSRA utilizing subjective evaluation of emotional experience turned out a feasible and promising method of analysis. It allows versatile exploration of the neurobiology of emotions and the neural correlates of actual and individual emotional experience. Thus, SSRA might be able to catch the idiosyncratic aspects of the emotional response better than traditional subtraction analysis.

Post-processing through linear regression

Directory of Open Access Journals (Sweden)

B. Van Schaeybroeck

2011-03-01

Full Text Available Various post-processing techniques are compared for both deterministic and ensemble forecasts, all based on linear regression between forecast data and observations. In order to evaluate the quality of the regression methods, three criteria are proposed, related to the effective correction of forecast error, the optimal variability of the corrected forecast and multicollinearity. The regression schemes under consideration include the ordinary least-square (OLS method, a new time-dependent Tikhonov regularization (TDTR method, the total least-square method, a new geometric-mean regression (GM, a recently introduced error-in-variables (EVMOS method and, finally, a "best member" OLS method. The advantages and drawbacks of each method are clarified.

These techniques are applied in the context of the 63 Lorenz system, whose model version is affected by both initial condition and model errors. For short forecast lead times, the number and choice of predictors plays an important role. Contrarily to the other techniques, GM degrades when the number of predictors increases. At intermediate lead times, linear regression is unable to provide corrections to the forecast and can sometimes degrade the performance (GM and the best member OLS with noise. At long lead times the regression schemes (EVMOS, TDTR which yield the correct variability and the largest correlation between ensemble error and spread, should be preferred.

A comparison of random forest regression and multiple linear regression for prediction in neuroscience.

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Smith, Paul F; Ganesh, Siva; Liu, Ping

2013-10-30

Regression is a common statistical tool for prediction in neuroscience. However, linear regression is by far the most common form of regression used, with regression trees receiving comparatively little attention. In this study, the results of conventional multiple linear regression (MLR) were compared with those of random forest regression (RFR), in the prediction of the concentrations of 9 neurochemicals in the vestibular nucleus complex and cerebellum that are part of the l-arginine biochemical pathway (agmatine, putrescine, spermidine, spermine, l-arginine, l-ornithine, l-citrulline, glutamate and γ-aminobutyric acid (GABA)). The R(2) values for the MLRs were higher than the proportion of variance explained values for the RFRs: 6/9 of them were ≥ 0.70 compared to 4/9 for RFRs. Even the variables that had the lowest R(2) values for the MLRs, e.g. ornithine (0.50) and glutamate (0.61), had much lower proportion of variance explained values for the RFRs (0.27 and 0.49, respectively). The RSE values for the MLRs were lower than those for the RFRs in all but two cases. In general, MLRs seemed to be superior to the RFRs in terms of predictive value and error. In the case of this data set, MLR appeared to be superior to RFR in terms of its explanatory value and error. This result suggests that MLR may have advantages over RFR for prediction in neuroscience with this kind of data set, but that RFR can still have good predictive value in some cases. Copyright © 2013 Elsevier B.V. All rights reserved.

Logistic regression applied to natural hazards: rare event logistic regression with replications

OpenAIRE

Guns, M.; Vanacker, Veerle

2012-01-01

Statistical analysis of natural hazards needs particular attention, as most of these phenomena are rare events. This study shows that the ordinary rare event logistic regression, as it is now commonly used in geomorphologic studies, does not always lead to a robust detection of controlling factors, as the results can be strongly sample-dependent. In this paper, we introduce some concepts of Monte Carlo simulations in rare event logistic regression. This technique, so-called rare event logisti...

Multilevel covariance regression with correlated random effects in the mean and variance structure.

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Quintero, Adrian; Lesaffre, Emmanuel

2017-09-01

Multivariate regression methods generally assume a constant covariance matrix for the observations. In case a heteroscedastic model is needed, the parametric and nonparametric covariance regression approaches can be restrictive in the literature. We propose a multilevel regression model for the mean and covariance structure, including random intercepts in both components and allowing for correlation between them. The implied conditional covariance function can be different across clusters as a result of the random effect in the variance structure. In addition, allowing for correlation between the random intercepts in the mean and covariance makes the model convenient for skewedly distributed responses. Furthermore, it permits us to analyse directly the relation between the mean response level and the variability in each cluster. Parameter estimation is carried out via Gibbs sampling. We compare the performance of our model to other covariance modelling approaches in a simulation study. Finally, the proposed model is applied to the RN4CAST dataset to identify the variables that impact burnout of nurses in Belgium. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Preliminary bioelectrical impedance analysis (BIA) equation for body composition assessment in young females from Colombia

International Nuclear Information System (INIS)

Caicedo, J C; González-Correa, C H; González-Correa, C A

2013-01-01

A previous study showed that reported BIA equations for body composition are not suitable for Colombian population. The purpose of this study was to develop and validate a preliminary BIA equation for body composition assessment in young females from Colombia, using hydrodensitometry as reference method. A sample of 30 young females was evaluated. Inclusion and exclusion criteria were defined to minimize the variability of BIA. Height, weight, BIA, residual lung volume (RV) and underwater weight (UWW) were measured. A preliminary BIA equation was developed (r 2 = 0.72, SEE = 2.48 kg) by stepwise multiple regression with fat-free mass (FFM) as dependent variable and weight, height and impedance measurements as independent variables. The quality of regression was evaluated and a cross-validation against 50% of sample confirmed that results obtained with the preliminary BIA equation is interchangeable with results obtained with hydrodensitometry (r 2 = 0.84, SEE = 2.62 kg). The preliminary BIA equation can be used for body composition assessment in young females from Colombia until a definitive equation is developed. The next step will be increasing the sample, including a second reference method, as deuterium oxide dilution (D 2 O), and using multi-frequency BIA (MF-BIA). It would also be desirable to develop equations for males and other ethnic groups in Colombia.

Aerobic endurance in young female athletes in respect to sexual maturation, age and growth

Directory of Open Access Journals (Sweden)

Maria Tereza Silveira Böhme

2004-12-01

Full Text Available The aims of this study were, in young female athletes: a to describe the development of aerobic endurance in relation to different sexual maturation stages by each chronological age; b to verify the existence of significant differences among the sexual maturation stages in each age; c to describe the development of aerobic endurance in relation to different ages by each sexual stage; d to verify the existence of significant differences among the ages by each sexual stage; e to verify the influence of chronological age, sexual maturation, adiposity, muscularity, physical growth and kind of sport on aerobic endurance. The sample comprised 305 female young athletes from 10 to 17 years of age, of basketball, handball, soccer and track and field, who were measured for their physical growth, adiposity, muscularity, sexual maturation stage and aerobic endurance. The variance and multiple regression analyses indicated that sexual maturation had no significant influence on the aerobic endurance of these female young athletes. RESUMO Este trabalho de pesquisa teve por objetivos, com relação a jovens atletas do sexo feminino: a descrever o desenvolvimento da resistência geral aeróbia considerando-se os diferentes níveis de maturação biológica em cada idade cronológica; b verificar a existência de diferenças significativas entre os níveis de maturação em cada idade cronológica; c descrever o desenvolvimento da resistência geral aeróbia considerando-se as diferentes idades cronológicas em cada nível de maturação biológica; d verificar a existência de diferenças significativas entre as idades cronológicas de mesmo estágio maturacional; e verificar a influência da maturação biológica, crescimento físico, adiposidade subcutânea, muscularidade, idade cronológica e o tipo de modalidade esportiva praticada sobre a resistência geral aeróbia. Para isso, uma amostra de 305 jovens atletas mulheres na faixa etária de 10 a 17 anos das

Landscape evaluation of female black bear habitat effectiveness and capability in the North Cascades, Washington.

Science.gov (United States)

William L. Gaines; Andrea L. Lyons; John F. Lehmkuhl; Kenneth J. Raedeke

2005-01-01

We used logistic regression to derive scaled resource selection functions (RSFs) for female black bears at two study areas in the North Cascades Mountains. We tested the hypothesis that the influence of roads would result in potential habitat effectiveness (RSFs without the influence of roads) being greater than realized habitat effectiveness (RSFs with roads). Roads...

An investigation of factors affecting elementary female student teachers' choice of science as a major at college level in Zimbabwe

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Mlenga, Francis Howard

The purpose of the study was to determine factors affecting elementary female student teachers' choice of science as a major at college level in Zimbabwe. The study was conducted at one of the Primary School Teachers' Colleges in Zimbabwe. A sample of two hundred and thirty-eight female student teachers was used in the study. Of these one hundred and forty-two were non-science majors who had been randomly selected, forty-one were science majors and forty-five were math majors. Both science and math majors were a convenient sample because the total enrollment of the two groups was small. All the subjects completed a survey questionnaire that had sixty-eight items. Ten students from the non-science majors were selected for individual interviews and the same was done for the science majors. A further eighteen were selected from the non-science majors and divided into three groups of six each for focus group interviews. The same was done for the science majors. The interviews were audio taped and transcribed. Data from the survey questionnaires were analyzed using Binary Logistic Regression which predicted factors that affected students' choice of science as a major. The transcribed interview data were analyzed used using domain, taxonomic and componential analyses. Results of the study indicated that elementary female students' choice of science as a major at college level is affected by students' attitudes toward science, teacher behavior, out-of-school experiences, role models, gender stereotyping, parental influence, peer influence, in-school experiences, and societal expectations, namely cultural and social expectations.

Thermal comfort indices of female Murrah buffaloes reared in the Eastern Amazon.

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da Silva, Jamile Andréa Rodrigues; de Araújo, Airton Alencar; Lourenço Júnior, José de Brito; dos Santos, Núbia de Fátima Alves; Garcia, Alexandre Rossetto; de Oliveira, Raimundo Parente

2015-09-01

The study aimed to develop new and more specific thermal comfort indices for buffaloes reared in the Amazon region. Twenty female Murrah buffaloes were studied for a year. The animals were fed in pasture with drinking water and mineral supplementation ad libitum. The following parameters were measured twice a week in the morning (7 AM) and afternoon (1 PM): air temperature (AT), relative air humidity (RH), dew point temperature (DPT), wet bulb temperature (WBT), black globe temperature (BGT), rectal temperature (RT), respiratory rate (RR), and body surface temperature (BST). The temperature and humidity index (THI), globe temperature and humidity index (GTHI), Benezra's comfort index (BTCI), and Ibéria's heat tolerance index (IHTI) were calculated so they could be compared to the new indices. Multivariate regression analyses were carried out using the canonical correlation model, and all indices were correlated with the physiological and climatic variables. Three pairs of indices (general, effective, and practical) were determined comprising the buffalo comfort climatic condition index (BCCCI) and the buffalo environmental comfort index (BECI). The indices were validated and a great agreement was found among the BCCCIs (general, effective, and practical), with 98.3 % between general and effective a.nd 92.6 % between general and practical. A significant correlation (P thermal stress in buffaloes reared in the Amazon.

Benefits of marriage on relative and conditional relative cancer survival differ between males and females in the USA.

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Merrill, Ray M; Johnson, Erin

2017-10-01

The purpose of the paper is to assess the influence of marital status on conditional relative survival of cancer according to sex. Analyses involved 779,978 males and 1,032,868 females diagnosed with 1 of 13 cancer types between 2000 and 2008, and followed through 2013. Data are from the Surveillance, Epidemiology, and End Results (SEER) Program. Regression models were adjusted for age, sex, race, and tumor stage. Five-year relative survival conditional on years already survived is higher among married patients with less lethal cancers (oral cavity and pharynx, colon and rectum, breast, urinary bladder, kidney and renal pelvis, melanoma of the skin, thyroid, lymphoma). For more lethal cancers, married patients have similar (liver, lung and bronchus, pancreas, leukemia) or poorer (brain and other nervous system) cancer survival. Separated/divorced or widowed patients have the lowest conditional relative survival rates. For most cancers, 5-year cancer relative survival rates conditional on time already survived through 5 years approach 70 to 90% of that for the general population. The beneficial effect of marriage on survival decreases with years already survived. Superior conditional relative survival rates in females decrease with time already survived and are less pronounced in married patients. Five-year relative survival rates improve with time already survived. The benefits of marriage on conditional relative survival are greater for less lethal cancers. Greater 5-year conditional relative survival rates in females narrow with time already survived and are less pronounced in married patients. Conditional relative survival rates of cancer can lead to more informed decisions and understanding regarding treatment and prognosis.

A Seemingly Unrelated Poisson Regression Model

OpenAIRE

King, Gary

1989-01-01

This article introduces a new estimator for the analysis of two contemporaneously correlated endogenous event count variables. This seemingly unrelated Poisson regression model (SUPREME) estimator combines the efficiencies created by single equation Poisson regression model estimators and insights from "seemingly unrelated" linear regression models.

Associations between psychological demands, decision latitude, and job strain with smoking in female hotel room cleaners in Las Vegas.

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Rugulies, Reiner; Scherzer, Teresa; Krause, Niklas

2008-01-01

Little is known of the impact of the work environment on smoking among women holding low-paid jobs in the service sector. To study the associations between the components of the demand-control model with smoking in hotel room cleaners. We conducted a survey on work and health among 776 female hotel room cleaners in Las Vegas. Associations between psychosocial work characteristics and smoking were analyzed with multivariate regression analyses. Psychosocial work characteristics were associated with smoking after adjustment for covariates. Effect estimates were substantially reduced by additional adjustment for ethnicity, but remained significant for high psychological demands and smoking prevalence (OR = 1.97, p = 0.02), high job strain and smoking prevalence (OR = 1.87, p = 0.04), and high job strain and smoking intensity (coefficient = 3.52, p = 0.03). When analyses were restricted to Hispanic workers and further adjusted for place of birth, low decision latitude (coefficient = 3.94, p = 0.04) and high job strain (coefficient = 4.57, p = 003) were associated with smoking intensity but not with smoking status. Workplace smoking cessation programs may benefit from a primary prevention component reducing job strain among service workers. More research is needed on perceived and objective differences in psychosocial work characteristics across ethnic, immigrant, and other social groups within the same occupation.

Recursive Algorithm For Linear Regression

Science.gov (United States)

Varanasi, S. V.

1988-01-01

Order of model determined easily. Linear-regression algorithhm includes recursive equations for coefficients of model of increased order. Algorithm eliminates duplicative calculations, facilitates search for minimum order of linear-regression model fitting set of data satisfactory.

Dating Violence among Male and Female Youth seeking Emergency Department Care

Science.gov (United States)

Singh, Vijay; Walton, Maureen A; Whiteside, Lauren K; Stoddard, Sarah; Epstein-Ngo, Quyen; Chermack, Stephen T; Cunningham, Rebecca M

2014-01-01

Objective To determine prevalence and correlates of dating violence, dating victimization, and dating aggression among males and females age 14–20 seeking emergency department (ED) care. Methods Systematic sampling of subjects age 14–20 seeking care at a single large academic ED between 9/2010- 3/2013. Participants completed a computerized, self-administered, cross-sectional survey of demographics, dating violence from physical abuse measures of the Conflict in Adolescent Dating Relationships Inventory, associated behaviors, and ED health service use. Separate analyses were conducted for males and females. Results 4389 youth (86.1% participation rate) were screened, and 4089 (mean age 17.5 years, 58% female) were eligible for analysis. Almost 1 in 5 females (n= 215, 18.4%) and 1 in 8 males (n= 212, 12.5%) reported past year dating violence. Of females, 10.6% reported dating victimization, and 14.6% dating aggression, while of males, 11.7% reported dating victimization, and 4.9% reported dating aggression. Multivariate analyses showed variables associated with any male dating violence were African American race (AOR 2.26, CI 1.54–3.32), alcohol misuse (AOR 1.03, CI 1.00–1.06), illicit drug misuse (AOR 2.38, CI 1.68–3.38), and depression (AOR 2.13, CI 1.46–3.10); any female dating violence was associated with African-American race (AOR 1.68, CI 1.25–2.25), public assistance (AOR 1.64, CI 1.28–2.09), grades D and below (AOR 1.62, CI 1.07–2.43), alcohol misuse (AOR 1.04, CI 1.02–1.07), illicit drug misuse (AOR 2.85, CI 2.22–3.66), depression (AOR 1.86, CI 1.42–2.44), and any past year ED visit for intentional injury (AOR 2.64, CI 1.30–5.40). Conclusions Nearly 1 of 6 male and female adolescents seeking ED care report recent dating violence, and health disparities remain among this population. Dating violence was strongly associated with alcohol, illicit drug misuse, and depression, and correlated with prior ED service utilization among female

Acceptability of an existing, female-controlled contraceptive method that could potentially protect against HIV: a comparison of diaphragm users and other method users.

Science.gov (United States)

Bird, Sheryl Thorburn; Harvey, S Marie; Maher, Julie E; Beckman, Linda J

2004-01-01

The diaphragm, an internal barrier contraceptive device, is a candidate for a female-controlled method for preventing human immunodeficiency virus (HIV) and other sexually transmitted infections (STIs). This study's objective was to examine how women who use the diaphragm differ from women using the pill and/or condoms with respect to factors hypothesized to influence the acceptability of contraceptive methods. Our goal was to increase understanding of who finds the diaphragm acceptable and why. We conducted a cross-sectional telephone survey with selected female members of a managed care organization. For this analysis, we limited the sample to 585 women currently using the diaphragm (n = 196), pill (n = 200), condoms (n = 132), or pill and condoms (n = 57). We conducted bivariate analyses and multinomial logistic regression analyses to assess the associations between selected characteristics and diaphragm use. Diaphragm use was significantly associated with several variables. Of particular interest, placing less importance on hormonal method characteristics was significantly associated with diaphragm use (versus use of the pill, condoms, or both). Placing more importance on barrier method attributes was significantly associated with diaphragm use (versus pill use, alone or with condoms). In addition, lower condom use self-efficacy was significantly associated with diaphragm use (versus condom use, alone or with pill). Lack of motivation to avoid HIV/STIs was significantly associated with using the diaphragm versus condoms (only). These results have important implications for future research, interventions, counseling strategies for providers, and product development. Our findings suggest that if the diaphragm protects against HIV, it could be a desirable option for some women.

Development of the rate of employment and unemployment of males and females in ten associated countries of EU

Directory of Open Access Journals (Sweden)

Jan Klíma

2004-01-01

Full Text Available The paper is focused on the evaluation the rates of employment and unemployment of women, men and as a whole in ten associated countries of EU. Rates of employment were evaluated in the period 1996-2002. Rates of unemployment were evaluated in the period 1996-2003. Employment of males in all ten associated countries of EU is higher then employment of females. Unemployment of females in the Czech Republic, Cyprus, Malta, Poland, Slovakia and Slovenia is higher than unemployment of males and in opposite unemployment of females in Estonia, Hungary, Lithuania and Latvia is lower than unemployment of males. Trends of rates of male, female and total employment and unemployment are evaluated. Methods of regression and correlation analysis, development trends and cluster analysis were applied for the mathematical-statistical analysis.