Full Text Available OBJECTIVE: To establish the reliability and validity of a shortened (10-item depression scale used among HIV-positive patients enrolled in the Drug Treatment Program in British Columbia, Canada. METHODS: The 10-item CES-D (Center for Epidemiologic Studies Depression Scale was examined among 563 participants who initiated antiretroviral therapy (ART between August 1, 1996 and June 30, 2002. Internal consistency of the scale was measured by Cronbach's alpha. Using the original CES-D 20 as primary criteria, comparisons were made using the Kappa statistic. Predictive accuracy of CES-D 10 was assessed by calculating sensitivity, specificity, positive predictive values and negative predictive values. Factor analysis was also performed to determine if the CES-D 10 contained the same factors of positive and negative affect found in the original development of the CES-D. RESULTS: The correlation between the original and the shortened scale is very high (Spearman correlation coefficient =0.97 (P<0.001. Internal consistency reliability coefficients of the CES-D 10 were satisfactory (Cronbach α=0.88. The CES-D 10 showed comparable accuracy to the original CES-D 20 in classifying participants with depressive symptoms (Kappa=0.82, P<0.001. Sensitivity of CES-D 10 was 91%; specificity was 92%; and positive predictive value was 92%. Factor analysis demonstrates that CES-D 10 contains the same underlying factors of positive and negative affect found in the original development of the CES-D 20. CONCLUSION: The 10-item CES-D is a comparable tool to measure depressive symptoms among HIV-positive research participants.
Baron, Emily Claire; Davies, Thandi; Lund, Crick
The 10-item Centre for Epidemiological Studies Depression Scale (CES-D-10) is a depression screening tool that has been used in the South African National Income Dynamics Study (NIDS), a national household panel study. This screening tool has not yet been validated in South Africa. This study aimed to establish the reliability and validity of the CES-D-10 in Zulu, Xhosa and Afrikaans. The CES-D-10's psychometric properties were also compared to the Patient Health Questionnaire (PHQ-9), a depression screening tool already validated in South Africa. Stratified random samples of Xhosa, Afrikaans and Zulu-speaking participants aged 15 years or older (N = 944) were recruited from Cape Town Metro and Ethekwini districts. Face-to-face interviews included socio-demographic questions, the CES-D-10, Patient Health Questionnaire (PHQ-9), and WHO Disability Assessment Schedule 2.0 (WHODAS). Major depression was determined using the Mini International Neuropsychiatric Interview. All instruments were translated and back-translated to English. Construct validity was examined using exploratory factor analysis with varimax rotation. Receiver Operating Characteristics (ROC) curves were used to investigate the CES-D-10 and PHQ-9's criterion validity, and compared using the DeLong method. Overall, 6.6, 18.0 and 6.9% of the Zulu, Afrikaans and Xhosa samples were diagnosed with depression, respectively. The CES-D-10 had acceptable internal consistency across samples (α = 0.69-0.89), and adequate concurrent validity, when compared to the PHQ-9 and WHODAS. The CES-D-10 area under the Receiver Operator Characteristic curve was good to excellent: 0.81 (95% CI 0.71-0.90) for Zulu, 0.93 (95% CI 0.90-0.96) for Afrikaans, and 0.94 (95% CI 0.89-0.99) for Xhosa. A cut-off of 12, 11 and 13 for Zulu, Afrikaans and Xhosa, respectively, generated the most balanced sensitivity, specificity and positive predictive value (Zulu: 71.4, 72.6% and 16.1%; Afrikaans: 84.6%, 84.0%, 53.7%; Xhosa: 81
Jang, Yuri; Kwag, Kyung Hwa; Chiriboga, David A
Given the emphasis on modesty and self-effacement in Asian societies, the present study explored differential item responses for 2 positive affect items (5 = Hopeful and 8 = Happy) on a short form of the Center for Epidemiologic Studies-Depression scale. The samples consisted of elderly non-Hispanic Whites (n = 450), Korean Americans (n = 519), and Koreans (n = 2,030). Multiple Indicator Multiple Cause models were estimated to identify the impact of group membership on responses to the positive affect items while controlling for the latent trait of depressive symptoms. The data revealed that Koreans and Korean Americans were less likely than non-Hispanic Whites to endorse the positive affect items. Compared with Korean Americans who were more acculturated to mainstream American culture, those who were less acculturated were less likely to endorse the positive affect items. Our findings support the notion that the way in which people endorse depressive symptoms is substantially influenced by cultural orientation. These findings call into question the common use of simple mean comparisons and a universal cutoff point across diverse cultural groups.
Opoliner, April; Blacker, Deborah; Fitzmaurice, Garrett; Becker, Anne
The CES-D is a commonly used self-report assessment for depressive symptomatology. However, its psychometric properties have not been evaluated in Fiji. This study aims to evaluate the reliability and validity of English language and Fijian vernacular versions in ethnic Fijian adolescent schoolgirls. As part of the HEALTHY Fiji study, ethnic Fijian female adolescents (N = 523) completed the CES-D. Participants selected to respond in English or the local vernacular. Reliability (internal consistency, item-total score correlation, and test-retest estimates), validity (associations with other proxies for depression) and factor structure were assessed. Evaluations considered differences between language versions. In this sample, the CES-D had a Cronbach's α of 0.81 and item-total score correlation coefficients ranged between 0.2 and 0.63. One week test-retest reliability (ICC(2)) was 0.57. CES-D scores were higher among individuals who endorsed feelings of depression and suicidality compared to those who did not. ROC analyses of the CES-D versus binary depression and suicidality variables produced AUCs around 0.70 and did not support a discrete cut-off for significant disturbance. Findings were similar across the two language groups. The CES-D has acceptable reliability and validity among ethnic Fijian female adolescents in English and in the Fijian vernacular language. Findings support its utility as a dimensional measure for depressive symptomatology in this study population. Further examination of its clinical utility for case finding for depression in Fijian school-based and community populations is warranted. © The Author(s) 2013.
Suh, Hanna; van Nuenen, Marieke; Rice, Kenneth G
Detecting psychological distress among international students can be challenging given diverse languages, cultural backgrounds, and lack of refined measurement properties of measures tailored to international students. Despite the challenges, ensuring that a psychological distress measure works effectively has considerable potential value for assessment purposes. The current study evaluates the measurement properties of a short 10-item version of Radloff's Center for Epidemiologic Studies Depression Scale (CES-D). Grounded in long-standing evidence on gender differences in depressive symptoms, specific attention was given to examining measurement invariance of the CES-D Short-form across women and men. Based on a large, two-cohort sample of international students ( N = 468), and through multiple analyses evaluating factor structure and measurement invariance, we derived an even briefer, seven-item single-factor form of the CES-D (CES-D Short-form International) that can be used with international students.
Full Text Available With the aim of verifying the suitability of the CES-D scale for use in long-term care institutions for older adults, the CES-D questionnaire was used to collect patient-reported assessments, and two well-known psychometric instruments – the Hospital Anxiety and Depression Scale (HADS and the Barthel Index of Abilities of Daily Living – were used to collect nurse-reported assessments, based on observations of patients’ behaviours. With regard to possible frequent cases of cognitive impairment and/or insufficient motivation to give sensible responses to CES-D questions, the patient-reported responses were collected from patients during one-on-one sessions with a nurse. The reliability, concurrent validity, and the trustworthiness of the obtained data were supported with proper values of the Cronbach’s alpha coefficient, 0.70 < alpha < 0.85, with significant correlation between CES-D and HADS-Depression, R = 0.50, p < 0.001, and with significant correlation between scores of particular CES-D items vs. final CES-D evaluations of depression, proved by significance p < 0.001 for 18 of 20 CES-D items. These findings supported the effectiveness of the one-on-one session methodology in questionnaire surveys for older adults. The postulation that cases of self-reported depression included somewhat different information about the patient than nurse-reported depression concerning the same patient was supported with the evidence that, in spite of the significant correlation between the Barthel Index and HADS-Depression, R = −0.17, p = 0.016, and in spite of the significant correlation between CES-D and HADS-Depression, the correlation between the Barthel Index and CES-D, equal to R = −0.08 was insignificant at p = 0.244. The findings of this study, considered jointly, support the valuableness of the CES-D scale for use in one-on-one surveys for older adults.
Covic, Tanya; Pallant, Julie F; Conaghan, Philip G; Tennant, Alan
Background The aim of this study was to test the internal validity of the total Center for Epidemiologic Studies-Depression (CES-D) scale using Rasch analysis in a rheumatoid arthritis (RA) population. Methods CES-D was administered to 157 patients with RA over three time points within a 12 month period. Rasch analysis was applied using RUMM2020 software to assess the overall fit of the model, the response scale used, individual item fit, differential item functioning (DIF) and person separation. Results Pooled data across three time points was shown to fit the Rasch model with removal of seven items from the original 20-item CES-D scale. It was necessary to rescore the response format from four to three categories in order to improve the scale's fit. Two items demonstrated some DIF for age and gender but were retained within the 13-item CES-D scale. A new cut point for depression score of 9 was found to correspond to the original cut point score of 16 in the full CES-D scale. Conclusion This Rasch analysis of the CES-D in a longstanding RA cohort resulted in the construction of a modified 13-item scale with good internal validity. Further validation of the modified scale is recommended particularly in relation to the new cut point for depression. PMID:17629902
Full Text Available Abstract Background The aim of this study was to test the internal validity of the total Center for Epidemiologic Studies-Depression (CES-D scale using Rasch analysis in a rheumatoid arthritis (RA population. Methods CES-D was administered to 157 patients with RA over three time points within a 12 month period. Rasch analysis was applied using RUMM2020 software to assess the overall fit of the model, the response scale used, individual item fit, differential item functioning (DIF and person separation. Results Pooled data across three time points was shown to fit the Rasch model with removal of seven items from the original 20-item CES-D scale. It was necessary to rescore the response format from four to three categories in order to improve the scale's fit. Two items demonstrated some DIF for age and gender but were retained within the 13-item CES-D scale. A new cut point for depression score of 9 was found to correspond to the original cut point score of 16 in the full CES-D scale. Conclusion This Rasch analysis of the CES-D in a longstanding RA cohort resulted in the construction of a modified 13-item scale with good internal validity. Further validation of the modified scale is recommended particularly in relation to the new cut point for depression.
Full Text Available Abstract Background Depression is common in rheumatoid arthritis (RA, however reported prevalence varies considerably. Two frequently used instruments to identify depression are the Center for Epidemiological Studies Depression (CES-D scale, and the Hospital Anxiety and Depression Scale (HADS. The objectives of this study were to test if the CES-D and HADS-D (a satisfy current modern psychometric standards for unidimensional measurement in an early RA sample; (b measure the same construct (i.e. depression; and (c identify similar levels of depression. Methods Data from the two scales completed by patients with early RA were fitted to the Rasch measurement model to show that (a each scale satisfies the criteria of fit to the model, including strict unidimensionality; (b that the scales can be co-calibrated onto a single underlying continuum of depression and to (c examine the location of the cut points on the underlying continuum as indication of the prevalence of depression. Results Ninety-two patients with early RA (62% female; mean age = 56.3, SD = 13.7 gave 141 sets of paired CES-D and HAD-D data. Fit of the data from the CES-D was found to be poor, and the scale had to be reduced to 13 items to satisfy Rasch measurement criteria whereas the HADS-D met model expectations from the outset. The 20 items combined (CES-D13 and HADS-D satisfied Rasch model expectations. The CES-D gave a much higher prevalence of depression than the HADS-D. Conclusion The CES-D in its present form is unsuitable for use in patients with early RA, and needs to be reduced to a 13-item scale. The HADS-D is valid for early RA and the two scales measure the same underlying construct but their cut points lead to different estimates of the level of depression. Revised cut points on the CES-D13 provide comparative prevalence rates.
Covic, Tanya; Pallant, Julie F; Tennant, Alan; Cox, Sally; Emery, Paul; Conaghan, Philip G
Background Depression is common in rheumatoid arthritis (RA), however reported prevalence varies considerably. Two frequently used instruments to identify depression are the Center for Epidemiological Studies Depression (CES-D) scale, and the Hospital Anxiety and Depression Scale (HADS). The objectives of this study were to test if the CES-D and HADS-D (a) satisfy current modern psychometric standards for unidimensional measurement in an early RA sample; (b) measure the same construct (i.e. depression); and (c) identify similar levels of depression. Methods Data from the two scales completed by patients with early RA were fitted to the Rasch measurement model to show that (a) each scale satisfies the criteria of fit to the model, including strict unidimensionality; (b) that the scales can be co-calibrated onto a single underlying continuum of depression and to (c) examine the location of the cut points on the underlying continuum as indication of the prevalence of depression. Results Ninety-two patients with early RA (62% female; mean age = 56.3, SD = 13.7) gave 141 sets of paired CES-D and HAD-D data. Fit of the data from the CES-D was found to be poor, and the scale had to be reduced to 13 items to satisfy Rasch measurement criteria whereas the HADS-D met model expectations from the outset. The 20 items combined (CES-D13 and HADS-D) satisfied Rasch model expectations. The CES-D gave a much higher prevalence of depression than the HADS-D. Conclusion The CES-D in its present form is unsuitable for use in patients with early RA, and needs to be reduced to a 13-item scale. The HADS-D is valid for early RA and the two scales measure the same underlying construct but their cut points lead to different estimates of the level of depression. Revised cut points on the CES-D13 provide comparative prevalence rates. PMID:19200388
Vanessa C Delisle
Full Text Available Center for Epidemiologic Studies Depression (CES-D Scale scores in English- and French-speaking Canadian systemic sclerosis (SSc patients are commonly pooled in analyses, but no studies have evaluated the metric equivalence of the English and French CES-D. The study objective was to examine the metric equivalence of the CES-D in English- and French-speaking SSc patients.The CES-D was completed by 1007 English-speaking and 248 French-speaking patients from the Canadian Scleroderma Research Group Registry. Confirmatory factor analysis (CFA was used to assess the factor structure in both samples. The Multiple-Indicator Multiple-Cause (MIMIC model was utilized to assess differential item functioning (DIF.A two-factor model (Positive and Negative affect showed excellent fit in both samples. Statistically significant, but small-magnitude, DIF was found for 3 of 20 CES-D items, including items 3 (Blues, 10 (Fearful, and 11 (Sleep. Prior to accounting for DIF, French-speaking patients had 0.08 of a standard deviation (SD lower latent scores for the Positive factor (95% confidence interval [CI]-0.25 to 0.08 and 0.09 SD higher scores (95% CI-0.07 to 0.24 for the Negative factor than English-speaking patients. After DIF correction, there was no change on the Positive factor and a non-significant increase of 0.04 SD on the Negative factor for French-speaking patients (difference = 0.13 SD, 95% CI-0.03 to 0.28.The English and French versions of the CES-D, despite minor DIF on several items, are substantively equivalent and can be used in studies that combine data from English- and French-speaking Canadian SSc patients.
Delisle, Vanessa C; Kwakkenbos, Linda; Hudson, Marie; Baron, Murray; Thombs, Brett D
Center for Epidemiologic Studies Depression (CES-D) Scale scores in English- and French-speaking Canadian systemic sclerosis (SSc) patients are commonly pooled in analyses, but no studies have evaluated the metric equivalence of the English and French CES-D. The study objective was to examine the metric equivalence of the CES-D in English- and French-speaking SSc patients. The CES-D was completed by 1007 English-speaking and 248 French-speaking patients from the Canadian Scleroderma Research Group Registry. Confirmatory factor analysis (CFA) was used to assess the factor structure in both samples. The Multiple-Indicator Multiple-Cause (MIMIC) model was utilized to assess differential item functioning (DIF). A two-factor model (Positive and Negative affect) showed excellent fit in both samples. Statistically significant, but small-magnitude, DIF was found for 3 of 20 CES-D items, including items 3 (Blues), 10 (Fearful), and 11 (Sleep). Prior to accounting for DIF, French-speaking patients had 0.08 of a standard deviation (SD) lower latent scores for the Positive factor (95% confidence interval [CI]-0.25 to 0.08) and 0.09 SD higher scores (95% CI-0.07 to 0.24) for the Negative factor than English-speaking patients. After DIF correction, there was no change on the Positive factor and a non-significant increase of 0.04 SD on the Negative factor for French-speaking patients (difference = 0.13 SD, 95% CI-0.03 to 0.28). The English and French versions of the CES-D, despite minor DIF on several items, are substantively equivalent and can be used in studies that combine data from English- and French-speaking Canadian SSc patients.
Wilcox, Holly; Field, Tiffany; Prodromidis, Margarita; Scafidi, Frank
The adequacy of the Beck Depression Inventory (BDI) and Center for Epidemiological Studies-Depression (CES-D) as screening instruments for adolescent depression is examined. Both are correlated with the Diagnostic Interview Schedule for Children, a clinical measure. BDI correlates more highly with Major Depression subscale, CES-D to Dysthymia…
Full Text Available Abstract Background Depression is a common co-morbid health problem in patients with diabetes that is underrecognised. Current international guidelines recommend screening for depression in patients with diabetes. Yet, few depression screening instruments have been validated for use in this particular group of patients. Aim of the present study was to investigate the psychometric properties of the Turkish version of the Centre for Epidemiologic Studies Depression Scale (CES-D in patients with type 2 diabetes. Methods A sample of 151 Turkish outpatients with type 2 diabetes completed the CES-D, the World Health Organization-Five Well-Being Index (WHO-5, and the Problem Areas in Diabetes scale (PAID. Explanatory factor analyses, various correlations and Cronbach's alpha were investigated to test the validity and reliability of the CES-D in Turkish diabetes outpatients. Results The original four-factor structure proposed by Radloff was not confirmed. Explanatory factor analyses revealed a two-factor structure representing two subscales: (1 depressed mood combined with somatic symptoms of depression and (2 positive affect. However, one item showed insufficient factor loadings. Cronbach's alpha of the total score was high (0.88, as were split-half coefficients (0.77-0.90. The correlation of the CES-D with the WHO-5 was the strongest (r = -0.70, and supported concurrent validity. Conclusion The CES-D appears to be a valid measure for the assessment of depression in Turkish diabetes patients. Future studies should investigate its sensitivity and specificity as well as test-retest reliability.
Jahn, Rebecca; Baumgartner, Josef S; van den Nest, Miriam; Friedrich, Fabian; Alexandrowicz, Rainer W; Wancata, Johannes
The "Center of Epidemiologic Studies - Depression scale" (CES-D) is a well-known screening tool for depression. Until now the criterion validity of the German version of the CES-D was not investigated in a sample of the adult general population. 508 study participants of the Austrian general population completed the CES-D. ICD-10 diagnoses were established by using the Schedules for Clinical Assessment in Neuropsychiatry (SCAN). Receiver Operating Characteristics (ROC) analysis was conducted. Possible gender differences were explored. Overall discriminating performance of the CES-D was sufficient (ROC-AUC 0,836). Using the traditional cut-off values of 15/16 and 21/22 respectively the sensitivity was 43.2 % and 32.4 %, respectively. The cut-off value developed on the basis of our sample was 9/10 with a sensitivity of 81.1 % und a specificity of 74.3 %. There were no significant gender differences. This is the first study investigating the criterion validity of the German version of the CES-D in the general population. The optimal cut-off values yielded sufficient sensitivity and specificity, comparable to the values of other screening tools. © Georg Thieme Verlag KG Stuttgart · New York.
Wang, Mengcheng; Armour, Cherie; Wu, Yan; Ren, Fen; Zhu, Xiongzhao; Yao, Shuqiao
The primary aim was to examine the depressive symptom structure of Mainland China adolescents using the Center for Epidemiologic Studies Depression Scale (CES-D). Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were simultaneously conducted to determine the structure of the CES-D in a large scale, representative adolescent samples recruited from Mainland China. Multigroup CFA (N = 5059, 48% boys, mean = 16.55±1.06) was utilized to test the factorial invariance of the depressive symptom structure, which was generated by EFA and confirmed by CFA across gender. The CES-D can be interpreted in terms of 3 symptom dimensions. Additionally, factorial invariance of the new proposed model across gender was supported at all assuming different degrees of invariance. Mainland Chinese adolescents have specific depressive symptom structure, which is consistent across gender. © 2013 Wiley Periodicals, Inc.
Missinne, Sarah; Vandeviver, Christophe; Van de Velde, Sarah; Bracke, Piet
Depression is one of the most prevalent mental disorders in later life. However, despite considerable research attention, great confusion remains regarding the association between ageing and depression. There is doubt as to whether a depression scale performs identically for different age groups and countries. Although measurement equivalence is a crucial prerequisite for valid comparisons across age groups and countries, it has not been established for the eight-item version of the Centre for Epidemiological Studies Depression Scale (CES-D8). Using multi-group confirmatory factor analysis, we assess configural, metric, and scalar measurement equivalence across two age groups (50-64 years of age and 65 or older) in eleven European countries, employing data from the Survey of Health, Ageing, and Retirement (SHARE). Results indicate that the construct of depression is comparable across age and country groups, allowing the substantive interpretation of correlates and mean levels of depressive symptoms. Copyright © 2014 Elsevier Inc. All rights reserved.
Kwakkenbos, Linda; Arthurs, Erin; van den Hoogen, Frank H. J.; Hudson, Marie; van Lankveld, Wim G. J. M.; Baron, Murray; van den Ende, Cornelia H. M.; Thombs, Brett D.
Objectives Increasingly, medical research involves patients who complete outcomes in different languages. This occurs in countries with more than one common language, such as Canada (French/English) or the United States (Spanish/English), as well as in international multi-centre collaborations, which are utilized frequently in rare diseases such as systemic sclerosis (SSc). In order to pool or compare outcomes, instruments should be measurement equivalent (invariant) across cultural or linguistic groups. This study provides an example of how to assess cross-language measurement equivalence by comparing the Center for Epidemiologic Studies Depression (CES-D) scale between English-speaking Canadian and Dutch SSc patients. Methods The CES-D was completed by 922 English-speaking Canadian and 213 Dutch SSc patients. Confirmatory factor analysis (CFA) was used to assess the factor structure in both samples. The Multiple-Indicator Multiple-Cause (MIMIC) model was utilized to assess the amount of differential item functioning (DIF). Results A two-factor model (positive and negative affect) showed excellent fit in both samples. Statistically significant, but small-magnitude, DIF was found for 3 of 20 items on the CES-D. The English-speaking Canadian sample endorsed more feeling-related symptoms, whereas the Dutch sample endorsed more somatic/retarded activity symptoms. The overall estimate in depression scores between English and Dutch was not influenced substantively by DIF. Conclusions CES-D scores from English-speaking Canadian and Dutch SSc patients can be compared and pooled without concern that measurement differences may substantively influence results. The importance of assessing cross-language measurement equivalence in rheumatology studies prior to pooling outcomes obtained in different languages should be emphasized. PMID:23326538
Grzywacz, Joseph G.; Hovey, Joseph D.; Seligman, Laura D.; Arcury, Thomas A.; Quandt, Sara A.
This article examines the feasibility of using a short-form version of the Center for Epidemiologic Studies-Depression Scale (CES-D) in community mental health research with Mexican immigrants. Several features of three published short versions of the CES-D were examined using data combined from seven diverse Mexican immigrant samples from across…
Chotorlishvili, L.; Skrinnikov, V.
It is well known that the appearance of non-reversibility in classical chaotic systems is connected with a local instability of phase trajectories relatively to a small change of initial conditions and parameters of the system. Classical chaotic systems reveal an exponential sensitivity to these changes. This leads to an exponential growth of initial error with time, and as the result after the statistical averaging over this error, the dynamics of the system becomes non-reversible. In spite of this, the question about the origin of non-reversibility in quantum case remains actual. The point is that the classical notion of instability of phase trajectories loses its sense during quantum consideration. The current work is dedicated to the clarification of the origin of non-reversibility in quantum chaotic systems. For this purpose we study a non-stationary dynamics of the chaotic quantum system. By analogy with classical chaos, we consider an influence of a small unavoidable error of the parameter of the system on the non-reversibility of the dynamics. It is shown in the Letter that due to the peculiarity of chaotic quantum systems, the statistical averaging over the small unavoidable error leads to the non-reversible transition from the pure state into the mixed one. The second part of the Letter is dedicated to the kinematic description of the chaotic quantum-mechanical system. Using the formalism of superoperators, a muster kinematic equation for chaotic quantum system was obtained from Liouville equation under a strict mathematical consideration
Emery Paul; Cox Sally; Tennant Alan; Pallant Julie F; Covic Tanya; Conaghan Philip G
Abstract Background Depression is common in rheumatoid arthritis (RA), however reported prevalence varies considerably. Two frequently used instruments to identify depression are the Center for Epidemiological Studies Depression (CES-D) scale, and the Hospital Anxiety and Depression Scale (HADS). The objectives of this study were to test if the CES-D and HADS-D (a) satisfy current modern psychometric standards for unidimensional measurement in an early RA sample; (b) measure the same construc...
Demirkan, A; Lahti, J; Direk, N; Viktorin, A; Lunetta, K L; Terracciano, A; Nalls, M A; Tanaka, T; Hek, K; Fornage, M; Wellmann, J; Cornelis, M C; Ollila, H M; Yu, L; Smith, J A; Pilling, L C; Isaacs, A; Palotie, A; Zhuang, W V; Zonderman, A; Faul, J D; Sutin, A; Meirelles, O; Mulas, A; Hofman, A; Uitterlinden, A; Rivadeneira, F; Perola, M; Zhao, W; Salomaa, V; Yaffe, K; Luik, A I; Liu, Y; Ding, J; Lichtenstein, P; Landén, M; Widen, E; Weir, D R; Llewellyn, D J; Murray, A; Kardia, S L R; Eriksson, J G; Koenen, K; Magnusson, P K E; Ferrucci, L; Mosley, T H; Cucca, F; Oostra, B A; Bennett, D A; Paunio, T; Berger, K; Harris, T B; Pedersen, N L; Murabito, J M; Tiemeier, H; van Duijn, C M; Räikkönen, K
Major depressive disorder (MDD) is moderately heritable, however genome-wide association studies (GWAS) for MDD, as well as for related continuous outcomes, have not shown consistent results. Attempts to elucidate the genetic basis of MDD may be hindered by heterogeneity in diagnosis. The Center for Epidemiological Studies Depression (CES-D) scale provides a widely used tool for measuring depressive symptoms clustered in four different domains which can be combined together into a total score but also can be analysed as separate symptom domains. We performed a meta-analysis of GWAS of the CES-D symptom clusters. We recruited 12 cohorts with the 20- or 10-item CES-D scale (32 528 persons). One single nucleotide polymorphism (SNP), rs713224, located near the brain-expressed melatonin receptor (MTNR1A) gene, was associated with the somatic complaints domain of depression symptoms, with borderline genome-wide significance (p discovery = 3.82 × 10-8). The SNP was analysed in an additional five cohorts comprising the replication sample (6813 persons). However, the association was not consistent among the replication sample (p discovery+replication = 1.10 × 10-6) with evidence of heterogeneity. Despite the effort to harmonize the phenotypes across cohorts and participants, our study is still underpowered to detect consistent association for depression, even by means of symptom classification. On the contrary, the SNP-based heritability and co-heritability estimation results suggest that a very minor part of the variation could be captured by GWAS, explaining the reason of sparse findings.
Cartierre, N; Coulon, N; Demerval, R
Screening depressivity among adolescents is a key public health priority. In order to measure the severity of depressive symptomatology, a four-dimensional 20 items scale called "Center for Epidemiological Studies-Depression Scale" (CES-D) was developed. A shorter 10-item version was developed and validated (Andresen et al.). For this brief version, several authors supported a two-factor structure - Negative and Positive affect - but the relationship between the two reversed-worded items of the Positive affect factor could be better accounted for by correlated errors. The aim of this study is triple: firstly to test a French version of the CES-D10 among adolescents; secondly to test the relevance of a one-dimensional structure by considering error correlation for Positive affect items; finally to examine the extent to which this structural model is invariant across gender. The sample was composed of 269 French middle school adolescents (139 girls and 130 boys, mean age: 13.8, SD=0.65). Confirmatory Factorial Analyses (CFA) using the LISREL 8.52 were conducted in order to assess the adjustment to the data of three factor models: a one-factor model, a two-factor model (Positive and Negative affect) and a one-factor model with specification of correlated errors between the two reverse-worded items. Then, multigroup analysis was conducted to test the scale invariance for girls and boys. Internal consistency of the CES-D10 was satisfying for the adolescent sample (α=0.75). The best fitting model is the one-factor model with correlated errors between the two items of the previous Positive affect factor (χ(2)/dl=2.50; GFI=0.939; CFI=0.894; RMSEA=0.076). This model presented a better statistical fit to the data than the one-factor model without error correlation: χ(2)(diff) (1)=22.14, pstatistic for the model with equality-constrained factor loadings was 121.31. The change in the overall Chi(2) is not statistically significant. This result implies that the model is
Rodríguez, José R; Rodríguez, Rosa Janet; Disdier, Orville M
The prevalence of diabetes mellitus in Puerto Ricans has been identified and reported as being disproportionately higher as compared to other metabolic pathologies. Recently, diabetes has been identified as the third cause of mortality in Puerto Rico (Puerto Rico Health Department, Vital Statistics Annual Report, 1999-2001). The Research Center, Education and Medical Services for Diabetes in Puerto Rico (also known as the "Centro de Diabetes para Puerto Rico" [CDPR]) is a public corporation in the island created by the government to reduce diabetes prevalence, mortality and morbidity. The CDPR offers Diabetes Self Management Educational Training Program Schools for patients (DSMETPS) island wide. The research design was an ex-post facto. As part of the process, patients are administered an extensive sociodemographic and health information questionnaire, which also includes the CES-D (a symptomatology depressive scale). This study pretends to describe the diabetic patient profiles (n=27) using information from the DSMETPS of the CDPR and explore the association with the CES-D. Variables such as patients' needs, knowledge and understanding of the condition (i.e., pathology management, type and medications utilized and exercise and nutritional patterns), patient attitudes to diabetes and their relations with the CES-D were explored. Results show a negative association, controlling for age and gender, between patients diabetic education/knowledge and CES-D score. Diabetes educators in Puerto Rico need to identify depressive symptomatology in order to prevent mental health complications in their patients since this may affect their future treatment and prognosis. An interdisciplinary team is recommended to improve the effectivity of the intervention.
Smith, Kevin Christopher
Soft-tissue augmentation of the face is an increasingly popular cosmetic procedure. In recent years, the number of available filling agents has also increased dramatically, improving the range of options available to physicians and patients. Understanding the different characteristics, capabilities, risks, and limitations of the available dermal and subdermal fillers can help physicians improve patient outcomes and reduce the risk of complications. The most popular fillers are those made from cross-linked hyaluronic acid (HA). A major and unique advantage of HA fillers is that they can be quickly and easily reversed by the injection of hyaluronidase into areas in which elimination of the filler is desired, either because there is excess HA in the area or to accelerate the resolution of an adverse reaction to treatment or to the product. In general, a lower incidence of complications (especially late-occurring or long-lasting effects) has been reported with HA fillers compared with the semi-permanent and permanent fillers. The implantation of nonreversible fillers requires more and different expertise on the part of the physician than does injection of HA fillers, and may produce effects and complications that are more difficult or impossible to manage even by the use of corrective surgery. Most practitioners use HA fillers as the foundation of their filler practices because they have found that HA fillers produce excellent aesthetic outcomes with high patient satisfaction, and a low incidence and severity of complications. Only limited subsets of physicians and patients have been able to justify the higher complexity and risks associated with the use of nonreversible fillers.
Jankowski, Konrad S
The study aimed to elucidate previously observed associations between morningness-eveningness and depressive symptomatology in university students. Relations between components of depressive symptomatology and morningness-eveningness were analysed. Nine hundred and seventy-four university students completed Polish versions of the Centre for Epidemiological Studies - Depression scale (CES-D; Polish translation appended to this paper) and the Composite Scale of Morningness. Principal component analysis (PCA) was used to test the structure of depressive symptoms. Pearson and partial correlations (with age and sex controlled), along with regression analyses with morning affect (MA) and circadian preference as predictors, were used. PCA revealed three components of depressive symptoms: depressed/somatic affect, positive affect, interpersonal relations. Greater MA was related to less depressive symptoms in three components. Morning circadian preference was related to less depressive symptoms in depressed/somatic and positive affects and unrelated to interpersonal relations. Both morningness-eveningness components exhibited stronger links with depressed/somatic and positive affects than with interpersonal relations. Three CES-D components exhibited stronger links with MA than with circadian preference. In regression analyses only MA was statistically significant for positive affect and better interpersonal relations, whereas more depressed/somatic affect was predicted by lower MA and morning circadian preference (relationship reversed compared to correlations). Self-report assessment. There are three groups of depressive symptoms in Polish university students. Associations of MA with depressed/somatic and positive affects are primarily responsible for the observed links between morningness-eveningness and depressive symptoms in university students. People with evening circadian preference whose MA is not lowered have less depressed/somatic affect. Copyright © 2016
Lehmann, Vicky; Makine, Ceylan; Karşıdağ, Cagatay
BACKGROUND: Depression is a common co-morbid health problem in patients with diabetes that is underrecognised. Current international guidelines recommend screening for depression in patients with diabetes. Yet, few depression screening instruments have been validated for use in this particular......-D, the World Health Organization-Five Well-Being Index (WHO-5), and the Problem Areas in Diabetes scale (PAID). Explanatory factor analyses, various correlations and Cronbach's alpha were investigated to test the validity and reliability of the CES-D in Turkish diabetes outpatients. RESULTS: The original four...... of the total score was high (0.88), as were split-half coefficients (0.77-0.90). The correlation of the CES-D with the WHO-5 was the strongest (r = -0.70), and supported concurrent validity. CONCLUSION: The CES-D appears to be a valid measure for the assessment of depression in Turkish diabetes patients...
Schroevers, MJ; Sanderman, R; van Sonderen, E; Ranchor, AV
This study examined the reliability and validity of a two-factor structure of the Center for Epidemiologic Studies Depression (CES-D) scale. The study was conducted in a large group of cancer patients (n = 475) and a matched reference group (n = 255). Both groups filled in a questionnaire at two
The Center for Epidemiologic Studies-Depression Scale (CES-D) is among the most widely used depression screening measures. Existing research suggests a higher-order factor structure of responses among older adults (factors labelled "depressive affect," "absence of well-being," "somatic symptoms," and "interpersonal affect," each loading upon a…
The Center for Epidemiologic Studies?Depression Scale (CES-D) is among the most widely used depression screening measures. Existing research suggests a higher order factor structure of responses among older adults (factors labeled as Depressive Affect, Absence of Well-being, Somatic Symptoms, and Interpersonal Affect each loading on a 2nd-order…
Jeremy W. Pettit
Full Text Available La mayoría de las investigaciones sobre la asociación entre la depresión y la mortalidad no han examinado distintos grupos de síntomas depresivos. Este estudio ex post facto examinó que aspectos de la depresión explican su asociación con la mortalidad. La Escala de Depresión del Centro de Estudios Epidemiológicos (CES-D fue administrada a 3.867 residentes comunitarios. El riesgo de mortalidad como función del estado depresivo y de cada uno de los 4 factores de la CES-D fue estimado con el modelo de azar proporcional de Cox. Los participantes deprimidos (CES-D > 16 tuvieron un riesgo elevado de mortalidad (HR 1,23, 95% CI 1,03-1,49 después de la corrección de variables sociodemográficos. Quejas somáticas fue el único factor que predijo la mortalidad (HR 1,19, 95% CI 1,03-1,38. Después de excluir Quejas somáticas, la CES-D no predijo la mortalidad (HR 0,98, 95% CI 0,79-1,21. La asociación entre los síntomas depresivos de la CES-D y la mortalidad parece ser una función del factor Quejas somáticas. Es posible que la asociación entre los síntomas depresivos no somáticos y la mortalidad no sea tan robusta como indican los hallazgos anteriores.
Full Text Available The Center of Epidemiologic Studies Depression Scale (CES-D is a commonly used self-report scale to measure depressive symptoms in the general population. In the present study, the Dutch version of the CES-D was administered to a sample of 837 Dutch-speaking adults of Belgium to examine the factor structure of the scale. Using confirmatory factory analysis (CFA, four first-order models and two second-order models were tested, and the second-order factor model with three pairs of correlated error terms provided the best fit to the data. Second, five socio-demographic variables (age, gender, education level, relation status, and family history of depression were included as covariates to the second-order factor model to explore the associations between background characteristics and the latent factor depression using a multiple indicators and multiple causes (MIMIC approach. Age had a significantly negative effect on depression, but the effect was not substantial. Female gender, lower education level, being single or widowed, and having a family history of depression were found to be significant predictors of higher levels of depression symptomatology. Finally, percentile norms on the CES-D raw scores were provided for subgroups of gender by education level for the general Dutch-speaking adult population of Belgium.
Sier, M. F.; van Gelder, L.; Ubbink, D. T.; Bemelman, W. A.; Oostenbroek, R. J.
Although stoma closure is considered a simple surgical intervention, the interval between construction and reversal is often prolonged, and some ileostomies may never be reversed. We evaluated possible predictors for non-reversal and prolonged interval between construction and reversal. In a cohort
Javaloyes, Miguel Angel; Lichtenfelz, Leandro; Piccione, Paolo
We develop the basics of a theory of almost isometries for spaces endowed with a quasi-metric. The case of non-reversible Finsler (more specifically, Randers) metrics is of particular interest, and it is studied in more detail. The main motivation arises from General Relativity, and more specifically in spacetimes endowed with a timelike conformal field K, in which case conformal diffeomorphisms correspond to almost isometries of the Fermat metrics defined in the spatial part. A series of results on the topology and the Lie group structure of conformal maps are discussed.
Piancino, Maria Grazia; Farina, Dario; Talpone, Francesca; Merlo, Andrea; Bracco, Pietro
The aim of this study was to characterize the kinematics and masseter muscle activation in unilateral posterior crossbite. Eighty-two children (8.6 +/- 1.3 yr of age) with unilateral posterior crossbite and 12 children (8.9 +/- 0.6 yr of age) with normal occlusion were selected for the study. Electromyography (EMG) and kinematics were concurrently recorded during mastication of a soft bolus and a hard bolus. The percentage of reverse cycles in the group of patients was 59.0 +/- 33.1% (soft bolus) and 69.7 +/- 29.7% (hard bolus) when chewing on the crossbite side. When chewing on the non-affected side, the number of reverse cycles was 16.7 +/- 24.5% (soft bolus) and 16.7 +/- 22.3% (hard bolus). The reverse cycles on the crossbite side were narrower with respect to the cycles on the non-affected side. Although both types of cycles in patients resulted in lower EMG activity of the masseter of the crossbite side than of the contralateral masseter, the activity of the non-affected side was larger for reverse than for non-reverse cycles. It was concluded that when chewing on the crossbite side, the masseter activity is reduced on the mastication side (crossbite) and is unaltered (non-reverse cycles) or increased (reverse) on the non-affected side.
Sier, M F; van Gelder, L; Ubbink, D T; Bemelman, W A; Oostenbroek, R J
Although stoma closure is considered a simple surgical intervention, the interval between construction and reversal is often prolonged, and some ileostomies may never be reversed. We evaluated possible predictors for non-reversal and prolonged interval between construction and reversal. In a cohort study of ileostomy patients treated in a large teaching hospital, we collected data from the surgical complication and enterostomal therapists' registries between January 2001 and December 2011. Parameters responsible for morbidity, mortality, length of stay and time interval between construction and reversal were analysed. Of 485 intentionally temporary ileostomies, 359 were reversed after a median of 5.6 months (IQR 3.8-8.9 months), while 126 (26%) remained permanent. End ileostomy and intra-abdominal abscess independently delayed reversal. Age, end ileostomy, higher body mass index and preoperative radiotherapy were independent factors for non-reversal. Median duration of hospitalisation for reversal was 7.0 days (5-13 days). Morbidity and mortality were 31 and 0.9%, respectively. In 20 patients (5.5%), re-ileostomy was necessary. A substantial number of ileostomies that are intended to be temporary will never be reversed. If reversed, the interval between construction and reversal is longer than anticipated, while morbidity after reversal and duration of hospitalisation are considerable. Besides a temporary ileostomy, there are two other options: no diversion or a permanent colostomy. Shared decision-making is to be preferred in these situations.
Gallet, Y.; Pavlov, V.; Shatsillo, A.; Hulot, G.
Constraining the evolution in the geomagnetic reversal frequency over hundreds of million years is not a trivial matter. Beyond the fact that there are long periods without reversals, known as superchrons, and periods with many reversals, the way the reversal frequency changes through time during reversing periods is still debated. A smooth evolution or a succession of stationary segments have both been suggested to account for the geomagnetic polarity time scale since the Middle-Late Jurassic. Sudden changes from a reversing mode to a non-reversing mode of the geodynamo may also well have happened, the switch between the two modes having then possibly been controlled by the thermal conditions at the core-mantle boundary. There is, nevertheless, a growing set of magnetostratigraphic data, which could help decipher a proper interpretation of the reversal history, in particular in the early Paleozoic and even during the Precambrian. Although yielding a fragmentary record, these data reveal the occurrence of both additional superchrons and periods characterized by extremely high, not to say extraordinary, magnetic reversal frequencies. In this talk, we will present a synthesis of these data, mainly obtained from Siberia, and discuss their implication for the magnetic reversal behavior over the past billion years.
Tomitaka, Shinichiro; Kawasaki, Yohei; Ide, Kazuki; Yamada, Hiroshi; Miyake, Hirotsugu; Furukawa, Toshiaki A; Furukaw, Toshiaki A
In a previous study, we reported that the distribution of total depressive symptoms scores according to the Center for Epidemiologic Studies Depression Scale (CES-D) in a general population is stable throughout middle adulthood and follows an exponential pattern except for at the lowest end of the symptom score. Furthermore, the individual distributions of 16 negative symptom items of the CES-D exhibit a common mathematical pattern. To confirm the reproducibility of these findings, we investigated the distribution of total depressive symptoms scores and 16 negative symptom items in a sample of Japanese employees. We analyzed 7624 employees aged 20-59 years who had participated in the Northern Japan Occupational Health Promotion Centers Collaboration Study for Mental Health. Depressive symptoms were assessed using the CES-D. The CES-D contains 20 items, each of which is scored in four grades: "rarely," "some," "much," and "most of the time." The descriptive statistics and frequency curves of the distributions were then compared according to age group. The distribution of total depressive symptoms scores appeared to be stable from 30-59 years. The right tail of the distribution for ages 30-59 years exhibited a linear pattern with a log-normal scale. The distributions of the 16 individual negative symptom items of the CES-D exhibited a common mathematical pattern which displayed different distributions with a boundary at "some." The distributions of the 16 negative symptom items from "some" to "most" followed a linear pattern with a log-normal scale. The distributions of the total depressive symptoms scores and individual negative symptom items in a Japanese occupational setting show the same patterns as those observed in a general population. These results show that the specific mathematical patterns of the distributions of total depressive symptoms scores and individual negative symptom items can be reproduced in an occupational population.
Le Bihan Etienne
Full Text Available Abstract Aim To analyse the relationships between mental health and employment commitment among prisoners and the long-term unemployed (LTU trying to return to work. Method Fifty-two of 62 male inmates of a semi-open prison (Givenich Penitentiary Centre, the only such unit in Luxembourg, and 69 LTU registered at the Luxembourg Employment Administration completed a questionnaire exploring: 1 mental health (measured by means of scales GHQ12 and CES-D; 2 employment commitment; 3 availability of a support network, self-esteem, empowerment; and 4 socio-demographic characteristics. Results Compared with LTU, inmates were younger, more had work experience (54.9% vs 26.1%, and more were educated to only a low level (71.1% vs 58.0%. The link between employment commitment and mental health in the LTU was the opposite of that seen among the prisoners: the more significant the perceived importance of employment, the worse the mental health (GHQ12 p = 0.003; CES-D p Conclusion The two groups clearly need professional support. Future research should further investigate the link between different forms of professional help and mental health. Randomized controlled trials could be carried out in both groups, with interventions to improve work commitment for prisoners and to help with getting a job for LTU. For those LTU who value employment but cannot find it, the best help may be psychological support.
Choi, Seung W; Schalet, Benjamin; Cook, Karon F; Cella, David
Interest in measuring patient-reported outcomes has increased dramatically in recent decades. This has simultaneously produced numerous assessment options and confusion. In the case of depressive symptoms, there are many commonly used options for measuring the same or a very similar concept. Public and professional reporting of scores can be confused by multiple scale ranges, normative levels, and clinical thresholds. A common reporting metric would have great value and can be achieved when similar instruments are administered to a single sample and then linked to each other to produce cross-walk score tables (e.g., Dorans, 2007; Kolen & Brennan, 2004). Using multiple procedures based on item response theory and equipercentile methods, we produced cross-walk tables linking 3 popular "legacy" depression instruments-the Center for Epidemiologic Studies Depression Scale (Radloff, 1977; N = 747), the Beck Depression Inventory-II (Beck, Steer, & Brown, 1996; N = 748), and the 9-item Patient Health Questionnaire (Kroenke, Spitzer, & Williams, 2001; N = 1,120)-to the depression metric of the National Institutes of Health (NIH) Patient-Reported Outcomes Measurement Information System (PROMIS; Cella et al., 2010). The PROMIS Depression metric is centered on the U.S. general population, matching the marginal distributions of gender, age, race, and education in the 2000 U.S. census (Liu et al., 2010). The linking relationships were evaluated by resampling small subsets and estimating confidence intervals for the differences between the observed and linked PROMIS scores; in addition, PROMIS cutoff scores for depression severity were estimated to correspond with those commonly used with the legacy measures. Our results allow clinicians and researchers to retrofit existing data of 3 popular depression measures to the PROMIS Depression metric and vice versa.
Franco-Díaz, Karen Lizbeth; Fernández-Niño, Julián Alfredo; Astudillo-García, Claudia Iveth
Introducción. La versión breve de la Escala de Depresión del Centro de Estudios Epidemiológicos (CESD) es un recurso factible para la tamización de los síntomas de depresión en la población general, pero no se ha reportado la prevalencia en la población indígena, ni su invarianza factorial en Latinoamérica.Objetivo. Describir la prevalencia de los síntomas de depresión y la invarianza factorial de la versión breve de la escala CES-D en población indígena mexicana.Materiales y métodos. Se hizo un estudio transversal en una muestra representativa de 37.165 adultos mexicanos de 20 a 59 años de edad. La identidad indígena se determinó mediante el propio reporte de la persona como hablante de una lengua indígena. Se conformaron ocho grupos de análisis según el sexo, el alfabetismo y el ser indígena. Se describió la prevalencia de los síntomas depresivos en cada grupo, así como la invarianza factorial de la configuración de los perfiles mediante un análisis factorial exploratorio. Las matrices de varianza y covarianza se compararon entre pares de perfiles usando el test modificado de Mantel.Resultados. La prevalencia de síntomas depresivos en mujeres indígenas que sabían leer fue de 16,8 % (IC95%: 13,4-20,3); en mujeres indígenas que no sabían leer, de 21,3 % (IC95%: 15,5-27,1); en hombres indígenas que sabían leer de 8,5 % (IC95%: 6,0-11,1), y en hombres indígenas que no sabían leer de 10,4 % (IC95%: 5,2-15,6). No se encontraron diferencias significativas en las cargas factoriales entre los perfiles.Conclusión. Se reportó una menor prevalencia de síntomas depresivos en indígenas que en la población no indígena. La escala CES-D en su versión breve mostró invarianza factorial al emplearla en la población indígena.
Full Text Available Veronika Müller,1 Gabriella Gálffy,1 Márta Orosz,1 Zsuzsanna Kováts,1 Balázs Odler,1 Olof Selroos,2 Lilla Tamási1 1Department of Pulmonology, Semmelweis University, Budapest, Hungary; 2Semeco AB, Ängelholm, Sweden Abstract: The choice of inhaler device for bronchodilator reversibility is crucial since suboptimal inhalation technique may influence the result. On the other hand, bronchodilator response also varies from time to time and may depend on patient characteristics. In this study, patients with airway obstruction (forced expiratory volume in 1 second [FEV1]/forced vital capacity [FVC] ratio <70% in chronic obstructive pulmonary disease [COPD]; <80% in asthma were included (n=121, age: 57.8±17.3 years. Bronchodilator reversibility (American Thoracic Society/European Respiratory Society criteria was tested in patients with COPD (n=63 and asthma and COPD overlap syndrome (ACOS; n=12. Forty-six asthmatics served as controls. Reversibility was tested with 400 µg salbutamol dry powder inhaler (Buventol Easyhaler, Orion Pharma Ltd, Espoo, Finland. Demographic data and patients’ perceptions of Easyhaler compared with β2-agonist pressurized metered dose inhalers (pMDIs were analyzed. American Thoracic Society/European Respiratory Society guideline defined reversibility was found in 21 out of 63 COPD patients and in two out of 12 ACOS patients. Airway obstruction was more severe in COPD patients as compared with controls (mean FEV1 and FEV1% predicted both P<0.0001. Average response to salbutamol was significantly lower in COPD patients compared with asthma controls (P<0.0001. Reversibility was equally often found in smokers as in never-smokers (33% vs 34%. Nonreversible COPD patients had higher mean weight, body mass index, and FEV1/FVC compared with reversible COPD patients. Most patients preferred Easyhaler and defined its use as simpler and more effective than use of a pMDI. Never-smokers and patients with asthma experienced
Tomitaka, Shinichiro; Kawasaki, Yohei; Ide, Kazuki; Akutagawa, Maiko; Yamada, Hiroshi; Furukawa, Toshiaki A; Ono, Yutaka
Previously, we proposed a model for ordinal scale scoring in which individual thresholds for each item constitute a distribution by each item. This lead us to hypothesize that the boundary curves of each depressive symptom score in the distribution of total depressive symptom scores follow a common mathematical model, which is expressed as the product of the frequency of the total depressive symptom scores and the probability of the cumulative distribution function of each item threshold. To verify this hypothesis, we investigated the boundary curves of the distribution of total depressive symptom scores in a general population. Data collected from 21,040 subjects who had completed the Center for Epidemiologic Studies Depression Scale (CES-D) questionnaire as part of a national Japanese survey were analyzed. The CES-D consists of 20 items (16 negative items and four positive items). The boundary curves of adjacent item scores in the distribution of total depressive symptom scores for the 16 negative items were analyzed using log-normal scales and curve fitting. The boundary curves of adjacent item scores for a given symptom approximated a common linear pattern on a log normal scale. Curve fitting showed that an exponential fit had a markedly higher coefficient of determination than either linear or quadratic fits. With negative affect items, the gap between the total score curve and boundary curve continuously increased with increasing total depressive symptom scores on a log-normal scale, whereas the boundary curves of positive affect items, which are not considered manifest variables of the latent trait, did not exhibit such increases in this gap. The results of the present study support the hypothesis that the boundary curves of each depressive symptom score in the distribution of total depressive symptom scores commonly follow the predicted mathematical model, which was verified to approximate an exponential mathematical pattern.
Full Text Available Background Previously, we proposed a model for ordinal scale scoring in which individual thresholds for each item constitute a distribution by each item. This lead us to hypothesize that the boundary curves of each depressive symptom score in the distribution of total depressive symptom scores follow a common mathematical model, which is expressed as the product of the frequency of the total depressive symptom scores and the probability of the cumulative distribution function of each item threshold. To verify this hypothesis, we investigated the boundary curves of the distribution of total depressive symptom scores in a general population. Methods Data collected from 21,040 subjects who had completed the Center for Epidemiologic Studies Depression Scale (CES-D questionnaire as part of a national Japanese survey were analyzed. The CES-D consists of 20 items (16 negative items and four positive items. The boundary curves of adjacent item scores in the distribution of total depressive symptom scores for the 16 negative items were analyzed using log-normal scales and curve fitting. Results The boundary curves of adjacent item scores for a given symptom approximated a common linear pattern on a log normal scale. Curve fitting showed that an exponential fit had a markedly higher coefficient of determination than either linear or quadratic fits. With negative affect items, the gap between the total score curve and boundary curve continuously increased with increasing total depressive symptom scores on a log-normal scale, whereas the boundary curves of positive affect items, which are not considered manifest variables of the latent trait, did not exhibit such increases in this gap. Discussion The results of the present study support the hypothesis that the boundary curves of each depressive symptom score in the distribution of total depressive symptom scores commonly follow the predicted mathematical model, which was verified to approximate an
Full Text Available Background Several recent studies have shown that total scores on depressive symptom measures in a general population approximate an exponential pattern except for the lower end of the distribution. Furthermore, we confirmed that the exponential pattern is present for the individual item responses on the Center for Epidemiologic Studies Depression Scale (CES-D. To confirm the reproducibility of such findings, we investigated the total score distribution and item responses of the Kessler Screening Scale for Psychological Distress (K6 in a nationally representative study. Methods Data were drawn from the National Survey of Midlife Development in the United States (MIDUS, which comprises four subsamples: (1 a national random digit dialing (RDD sample, (2 oversamples from five metropolitan areas, (3 siblings of individuals from the RDD sample, and (4 a national RDD sample of twin pairs. K6 items are scored using a 5-point scale: “none of the time,” “a little of the time,” “some of the time,” “most of the time,” and “all of the time.” The pattern of total score distribution and item responses were analyzed using graphical analysis and exponential regression model. Results The total score distributions of the four subsamples exhibited an exponential pattern with similar rate parameters. The item responses of the K6 approximated a linear pattern from “a little of the time” to “all of the time” on log-normal scales, while “none of the time” response was not related to this exponential pattern. Discussion The total score distribution and item responses of the K6 showed exponential patterns, consistent with other depressive symptom scales.
This article follows the development of test items (see "Language Assessment Quarterly", Volume 3 Issue 1, pp. 71-79 for the article "Test and Item Specifications Development"), beginning with a review of test and item specifications, then proceeding to writing and editing of items, pretesting and analysis, and finally selection of an item for a…
The TIS-RP group informs users that shipping of small radioactive items is normally guaranteed within 24 hours from the time the material is handed in at the TIS-RP service. This time is imposed by the necessary procedures (identification of the radionuclides, determination of dose rate and massive objects require a longer procedure and will therefore take longer.
Fernandez Carratala, L.
There is an increasing difficulty for purchasing safety related spare items, with certifications by manufacturers for maintaining the original qualifications of the equipment of destination. The main reasons are, on the top of the logical evolution of technology, applied to the new manufactured components, the quitting of nuclear specific production lines and the evolution of manufacturers quality systems, originally based on nuclear codes and standards, to conventional industry standards. To face this problem, for many years different Dedication processes have been implemented to verify whether a commercial grade element is acceptable to be used in safety related applications. In the same way, due to our particular position regarding the spare part supplies, mainly from markets others than the american, C.N. Trillo has developed a methodology called Spare Items Validation. This methodology, which is originally based on dedication processes, is not a single process but a group of coordinated processes involving engineering, quality and management activities. These are to be performed on the spare item itself, its design control, its fabrication and its supply for allowing its use in destinations with specific requirements. The scope of application is not only focussed on safety related items, but also to complex design, high cost or plant reliability related components. The implementation in C.N. Trillo has been mainly curried out by merging, modifying and making the most of processes and activities which were already being performed in the company. (Author)
Kleinert, Harold L.; And Others
A program used to teach moderately to severely mentally handicapped students to select the lower priced items in actual shopping activities is described. Through a five-phase process, students are taught to compare prices themselves as well as take into consideration variations in the sizes of containers and varying product weights. (VW)
Gierl, Mark J.; Lai, Hollis
Automatic item generation represents a relatively new but rapidly evolving research area where cognitive and psychometric theories are used to produce tests that include items generated using computer technology. Automatic item generation requires two steps. First, test development specialists create item models, which are comparable to templates…
Akkermans, Wies; Muraki, Eiji
For trinary partial credit items the shape of the item information and the item discrimination function is examined in relation to the item parameters. In particular, it is shown that these functions are unimodal if δ2 – δ1 < 4 ln 2 and bimodal otherwise. The locations and values of the maxima are
MacCann, Robert G.; Stanley, Gordon
An item banking method that does not use Item Response Theory (IRT) is described. This method provides a comparable grading system across schools that would be suitable for low-stakes testing. It uses the Angoff standard-setting method to obtain item ratings that are stored with each item. An example of such a grading system is given, showing how…
The TIS-RP group informs users that shipping of small radioactive items is normally guaranteed within 24 hours from the time the material is handed in at the TIS-RP service. This time is imposed by the necessary procedures (identification of the radionuclides, determination of dose rate, preparation of the package and related paperwork). Large and massive objects require a longer procedure and will therefore take longer.
Doolittle, Allen E.; Cleary, T. Anne
Eight randomly equivalent samples of high school seniors were each given a unique form of the ACT Assessment Mathematics Usage Test (ACTM). Signed measures of differential item performance (DIP) were obtained for each item in the eight ACTM forms. DIP estimates were analyzed and a significant item category effect was found. (Author/LMO)
Tutz, Gerhard; Berger, Moritz
A novel method for the identification of differential item functioning (DIF) by means of recursive partitioning techniques is proposed. We assume an extension of the Rasch model that allows for DIF being induced by an arbitrary number of covariates for each item. Recursive partitioning on the item level results in one tree for each item and leads to simultaneous selection of items and variables that induce DIF. For each item, it is possible to detect groups of subjects with different item difficulties, defined by combinations of characteristics that are not pre-specified. The way a DIF item is determined by covariates is visualized in a small tree and therefore easily accessible. An algorithm is proposed that is based on permutation tests. Various simulation studies, including the comparison with traditional approaches to identify items with DIF, show the applicability and the competitive performance of the method. Two applications illustrate the usefulness and the advantages of the new method.
Panjaitan, R. L.; Irawati, R.; Sujana, A.; Hanifah, N.; Djuanda, D.
In several literatures about evaluation and test analysis, it is common to find that there are calculations of item validity as well as item discrimination index (D) with different formula for each. Meanwhile, other resources said that item discrimination index could be obtained by calculating the correlation between the testee’s score in a particular item and the testee’s score on the overall test, which is actually the same concept as item validity. Some research reports, especially undergraduate theses tend to include both item validity and item discrimination index in the instrument analysis. It seems that these concepts might overlap for both reflect the test quality on measuring the examinees’ ability. In this paper, examples of some results of data processing on item validity and item discrimination index were compared. It would be discussed whether item validity and item discrimination index can be represented by one of them only or it should be better to present both calculations for simple test analysis, especially in undergraduate theses where test analyses were included.
Gideon P. De Bruin
Full Text Available The factor analysis of items often produces spurious results in the sense that unidimensional scales appear multidimensional. This may be ascribed to failure in meeting the assumptions of linearity and normality on which factor analysis is based. Item response theory is explicitly designed for the modelling of the non-linear relations between ordinal variables and provides a strong alternative to the factor analysis of items. Items may also be combined in parcels that are more likely to satisfy the assumptions of factor analysis than do the items. The use of the Rasch rating scale model and the factor analysis of parcels is illustrated with data obtained with the Locus of Control Inventory. The results of these analyses are compared with the results obtained through the factor analysis of items. It is shown that the Rasch rating scale model and the factoring of parcels produce superior results to the factor analysis of items. Recommendations for the analysis of scales are made. Opsomming Die faktorontleding van items lewer dikwels misleidende resultate op, veral in die opsig dat eendimensionele skale as meerdimensioneel voorkom. Hierdie resultate kan dikwels daaraan toegeskryf word dat daar nie aan die aannames van lineariteit en normaliteit waarop faktorontleding berus, voldoen word nie. Itemresponsteorie, wat eksplisiet vir die modellering van die nie-liniêre verbande tussen ordinale items ontwerp is, bied ’n aantreklike alternatief vir die faktorontleding van items. Items kan ook in pakkies gegroepeer word wat meer waarskynlik aan die aannames van faktorontleding voldoen as individuele items. Die gebruik van die Rasch beoordelingskaalmodel en die faktorontleding van pakkies word aan die hand van data wat met die Lokus van Beheervraelys verkry is, gedemonstreer. Die resultate van hierdie ontledings word vergelyk met die resultate wat deur ‘n faktorontleding van die individuele items verkry is. Die resultate dui daarop dat die Rasch
Item response theory (IRT) is a framework for modeling and analyzing item response ... data. Though, there is an argument that the evaluation of fit in IRT modeling has been ... National Council on Measurement in Education ... model data fit should be based on three types of ... prediction should be assessed through the.
Yang, Ji Seung; Zheng, Xiaying
The purpose of this article is to introduce and review the capability and performance of the Stata item response theory (IRT) package that is available from Stata v.14, 2015. Using a simulated data set and a publicly available item response data set extracted from Programme of International Student Assessment, we review the IRT package from…
Wang, Wen-Chung; Shih, Ching-Lin
Three multiple indicators-multiple causes (MIMIC) methods, namely, the standard MIMIC method (M-ST), the MIMIC method with scale purification (M-SP), and the MIMIC method with a pure anchor (M-PA), were developed to assess differential item functioning (DIF) in polytomous items. In a series of simulations, it appeared that all three methods…
Mellenbergh, Gideon J.; van der Linden, Wim J.
Three item selection methods for criterion-referenced tests are examined: the classical theory of item difficulty and item-test correlation; the latent trait theory of item characteristic curves; and a decision-theoretic approach for optimal item selection. Item contribution to the standardized expected utility of mastery testing is discussed. (CM)
Haberman, Shelby J; Sinharay, Sandip; Chon, Kyong Hee
Residual analysis (e.g. Hambleton & Swaminathan, Item response theory: principles and applications, Kluwer Academic, Boston, 1985; Hambleton, Swaminathan, & Rogers, Fundamentals of item response theory, Sage, Newbury Park, 1991) is a popular method to assess fit of item response theory (IRT) models. We suggest a form of residual analysis that may be applied to assess item fit for unidimensional IRT models. The residual analysis consists of a comparison of the maximum-likelihood estimate of the item characteristic curve with an alternative ratio estimate of the item characteristic curve. The large sample distribution of the residual is proved to be standardized normal when the IRT model fits the data. We compare the performance of our suggested residual to the standardized residual of Hambleton et al. (Fundamentals of item response theory, Sage, Newbury Park, 1991) in a detailed simulation study. We then calculate our suggested residuals using data from an operational test. The residuals appear to be useful in assessing the item fit for unidimensional IRT models.
This List includes fifteen species of bird, and at the thirteenth Conference of the Parties in Catania, Sicily in November 2003, an Action Plan for the conservation of these species was adopted, following similar plans on monk seal, marine turtles, cetaceans and marine vegetation. The Action Plan for Birds notes initiatives ...
Smallest detectable change and test-retest reliability of a self-reported outcome measure: Results of the Center for Epidemiologic Studies Depression Scale, General Self-Efficacy Scale, and 12-item General Health Questionnaire.
Ohno, Shotaro; Takahashi, Kana; Inoue, Aimi; Takada, Koki; Ishihara, Yoshiaki; Tanigawa, Masaru; Hirao, Kazuki
This study aims to examine the smallest detectable change (SDC) and test-retest reliability of the Center for Epidemiologic Studies Depression Scale (CES-D), General Self-Efficacy Scale (GSES), and 12-item General Health Questionnaire (GHQ-12). We tested 154 young adults at baseline and 2 weeks later. We calculated the intra-class correlation coefficients (ICCs) for test-retest reliability with a two-way random effects model for agreement. We then calculated the standard error of measurement (SEM) for agreement using the ICC formula. The SEM for agreement was used to calculate SDC values at the individual level (SDC ind ) and group level (SDC group ). The study participants included 137 young adults. The ICCs for all self-reported outcome measurement scales exceeded 0.70. The SEM of CES-D was 3.64, leading to an SDC ind of 10.10 points and SDC group of 0.86 points. The SEM of GSES was 1.56, leading to an SDC ind of 4.33 points and SDC group of 0.37 points. The SEM of GHQ-12 with bimodal scoring was 1.47, leading to an SDC ind of 4.06 points and SDC group of 0.35 points. The SEM of GHQ-12 with Likert scoring was 2.44, leading to an SDC ind of 6.76 points and SDC group of 0.58 points. To confirm that the change was not a result of measurement error, a score of self-reported outcome measurement scales would need to change by an amount greater than these SDC values. This has important implications for clinicians and epidemiologists when assessing outcomes. © 2017 John Wiley & Sons, Ltd.
... AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Texts of Provisions and Clauses 852.214-72... 2008) Bids on * will be given equal consideration along with bids on ** and any such bids received... .** * Contracting officer will insert an alternate item that is considered acceptable. ** Contracting officer will...
The sequential model can be used to describe the variable resulting from a sequential scoring process. In this paper two more item response models are investigated with respect to their suitability for sequential scoring: the partial credit model and the graded response model. The investigation is
Item response theory (IRT) is a framework for modeling and analyzing item response data. Item-level modeling gives IRT advantages over classical test theory. The fit of an item score pattern to an item response theory (IRT) models is a necessary condition that must be assessed for further use of item and models that best fit ...
Huggins-Manley, Anne Corinne
This study defines subpopulation item parameter drift (SIPD) as a change in item parameters over time that is dependent on subpopulations of examinees, and hypothesizes that the presence of SIPD in anchor items is associated with bias and/or lack of invariance in three psychometric outcomes. Results show that SIPD in anchor items is associated…
Glas, Cornelis A.W.; Eggen, T.J.H.M.; Veldkamp, B.P.
Item response theory is usually applied to items with a selected-response format, such as multiple choice items, whereas generalizability theory is usually applied to constructed-response tasks assessed by raters. However, in many situations, raters may use rating scales consisting of items with a
Glas, Cornelis A.W.; Eggen, T.J.H.M.; Veldkamp, B.P.
Item response theory is usually applied to items with a selected-response format, such as multiple choice items, whereas generalizability theory is usually applied to constructed-response tasks assessed by raters. However, in many situations, raters may use rating scales consisting of items with a selected-response format. This chapter presents a short overview of how item response theory and generalizability theory were integrated to model such assessments. Further, the precision of the esti...
Eutalia Aparecida Candido de Araujo
Full Text Available A preocupação com medidas de traços psicológicos é antiga, sendo que muitos estudos e propostas de métodos foram desenvolvidos no sentido de alcançar este objetivo. Entre os trabalhos propostos, destaca-se a Teoria da Resposta ao Item (TRI que, a princípio, veio completar limitações da Teoria Clássica de Medidas, empregada em larga escala até hoje na medida de traços psicológicos. O ponto principal da TRI é que ela leva em consideração o item particularmente, sem relevar os escores totais; portanto, as conclusões não dependem apenas do teste ou questionário, mas de cada item que o compõe. Este artigo propõe-se a apresentar esta Teoria que revolucionou a teoria de medidas.La preocupación con las medidas de los rasgos psicológicos es antigua y muchos estudios y propuestas de métodos fueron desarrollados para lograr este objetivo. Entre estas propuestas de trabajo se incluye la Teoría de la Respuesta al Ítem (TRI que, en principio, vino a completar las limitaciones de la Teoría Clásica de los Tests, ampliamente utilizada hasta hoy en la medida de los rasgos psicológicos. El punto principal de la TRI es que se tiene en cuenta el punto concreto, sin relevar las puntuaciones totales; por lo tanto, los resultados no sólo dependen de la prueba o cuestionario, sino que de cada ítem que lo compone. En este artículo se propone presentar la Teoría que revolucionó la teoría de medidas.The concern with measures of psychological traits is old and many studies and proposals of methods were developed to achieve this goal. Among these proposed methods highlights the Item Response Theory (IRT that, in principle, came to complete limitations of the Classical Test Theory, which is widely used until nowadays in the measurement of psychological traits. The main point of IRT is that it takes into account the item in particular, not relieving the total scores; therefore, the findings do not only depend on the test or questionnaire
Hougaard, Jens Leth; Moulin, Hervé
We ask how to share the cost of finitely many public goods (items) among users with different needs: some smaller subsets of items are enough to serve the needs of each user, yet the cost of all items must be covered, even if this entails inefficiently paying for redundant items. Typical examples...... are network connectivity problems when an existing (possibly inefficient) network must be maintained. We axiomatize a family cost ratios based on simple liability indices, one for each agent and for each item, measuring the relative worth of this item across agents, and generating cost allocation rules...... additive in costs....
Fukuhara, Hirotaka; Kamata, Akihito
A differential item functioning (DIF) detection method for testlet-based data was proposed and evaluated in this study. The proposed DIF model is an extension of a bifactor multidimensional item response theory (MIRT) model for testlets. Unlike traditional item response theory (IRT) DIF models, the proposed model takes testlet effects into…
Young, William R.
Natural disasters, such as hurricanes, floods, tornados, and tsunami, are becoming a greater problem as climate change impacts our environment. Disasters, whether natural or man made, destroy lives, homes, businesses and the natural environment. Such disasters can happen with little or no warning, leaving hundreds or even thousands of people without medical services, potable water, sanitation, communications and electrical services for up to several weeks. In our modern world, the need for electricity has become a necessity. Modern building codes and new disaster resistant building practices are reducing the damage to homes and businesses. Emergency gasoline and diesel generators are becoming common place for power outages. Generators need fuel, which may not be available after a disaster, but Photovoltaic (solar-electric) systems supply electricity without petroleum fuel as they are powered by the sun. Photovoltaic (PV) systems can provide electrical power for a home or business. PV systems can operate as utility interactive or stand-alone with battery backup. Determining your critical load items and sizing the photovoltaic system for those critical items, guarantees their operation in a disaster.
Gierl, Mark J; Lai, Hollis; Turner, Simon R
Many tests of medical knowledge, from the undergraduate level to the level of certification and licensure, contain multiple-choice items. Although these are efficient in measuring examinees' knowledge and skills across diverse content areas, multiple-choice items are time-consuming and expensive to create. Changes in student assessment brought about by new forms of computer-based testing have created the demand for large numbers of multiple-choice items. Our current approaches to item development cannot meet this demand. We present a methodology for developing multiple-choice items based on automatic item generation (AIG) concepts and procedures. We describe a three-stage approach to AIG and we illustrate this approach by generating multiple-choice items for a medical licensure test in the content area of surgery. To generate multiple-choice items, our method requires a three-stage process. Firstly, a cognitive model is created by content specialists. Secondly, item models are developed using the content from the cognitive model. Thirdly, items are generated from the item models using computer software. Using this methodology, we generated 1248 multiple-choice items from one item model. Automatic item generation is a process that involves using models to generate items using computer technology. With our method, content specialists identify and structure the content for the test items, and computer technology systematically combines the content to generate new test items. By combining these outcomes, items can be generated automatically. © Blackwell Publishing Ltd 2012.
Hiscox, Michael D.
Educational item banking presents observers with a considerable paradox. The development of test items from scratch is viewed as wasteful, a luxury in times of declining resources. On the other hand, item banking has failed to become a mature technology despite large amounts of money and the efforts of talented professionals. The question of which…
... DEPARTMENT OF DEFENSE Defense Acquisition Regulations System Commercial Item Handbook AGENCY.... SUMMARY: DoD has updated its Commercial Item Handbook. The purpose of the Handbook is to help acquisition personnel develop sound business strategies for procuring commercial items. DoD is seeking industry input on...
Rikers, Jos H.A.N.
The process of writing test items is analyzed, and a blueprint is presented for an authoring system for test item writing to reduce invalidity and to structure the process of item writing. The developmental methodology is introduced, and the first steps in the process are reported. A historical
Dorn, B.; de Haan, R.; Schlotter, I.; Röthe, J.
We consider the following control problem on fair allocation of indivisible goods. Given a set I of items and a set of agents, each having strict linear preference over the items, we ask for a minimum subset of the items whose deletion guarantees the existence of a proportional allocation in the
Tinari, Frank D.
Computerized analysis of multiple choice test items is explained. Examples of item analysis applications in the introductory economics course are discussed with respect to three objectives: to evaluate learning; to improve test items; and to help improve classroom instruction. Problems, costs and benefits of the procedures are identified. (JMD)
Abbott, J.A.; Waddoups, I.G.
This report responds to the Department of Energy's request that Sandia National Laboratories compare existing technologies against several advanced technologies as they apply to DOE needs to monitor the movement of material, weapons, or personnel for safety and security programs. The authors describe several material control systems, discuss their technologies, suggest possible applications, discuss assets and limitations, and project costs for each system. The following systems are described: WATCH system (Wireless Alarm Transmission of Container Handling); Tag system (an electrostatic proximity sensor); PANTRAK system (Personnel And Material Tracking); VRIS (Vault Remote Inventory System); VSIS (Vault Safety and Inventory System); AIMS (Authenticated Item Monitoring System); EIVS (Experimental Inventory Verification System); Metrox system (canister monitoring system); TCATS (Target Cueing And Tracking System); LGVSS (Light Grid Vault Surveillance System); CSS (Container Safeguards System); SAMMS (Security Alarm and Material Monitoring System); FOIDS (Fiber Optic Intelligence ampersand Detection System); GRADS (Graded Radiation Detection System); and PINPAL (Physical Inventory Pallet)
Abbott, J.A. [EG & G Energy Measurements, Albuquerque, NM (United States); Waddoups, I.G. [Sandia National Labs., Albuquerque, NM (United States)
This report responds to the Department of Energy`s request that Sandia National Laboratories compare existing technologies against several advanced technologies as they apply to DOE needs to monitor the movement of material, weapons, or personnel for safety and security programs. The authors describe several material control systems, discuss their technologies, suggest possible applications, discuss assets and limitations, and project costs for each system. The following systems are described: WATCH system (Wireless Alarm Transmission of Container Handling); Tag system (an electrostatic proximity sensor); PANTRAK system (Personnel And Material Tracking); VRIS (Vault Remote Inventory System); VSIS (Vault Safety and Inventory System); AIMS (Authenticated Item Monitoring System); EIVS (Experimental Inventory Verification System); Metrox system (canister monitoring system); TCATS (Target Cueing And Tracking System); LGVSS (Light Grid Vault Surveillance System); CSS (Container Safeguards System); SAMMS (Security Alarm and Material Monitoring System); FOIDS (Fiber Optic Intelligence & Detection System); GRADS (Graded Radiation Detection System); and PINPAL (Physical Inventory Pallet).
Hamane, Ryoso; Itoh, Toshiya; Tomita, Kouhei
When a store sells items to customers, the store wishes to determine the prices of the items to maximize its profit. Intuitively, if the store sells the items with low (resp. high) prices, the customers buy more (resp. less) items, which provides less profit to the store. So it would be hard for the store to decide the prices of items. Assume that the store has a set V of n items and there is a set E of m customers who wish to buy those items, and also assume that each item i ∈ V has the production cost di and each customer ej ∈ E has the valuation vj on the bundle ej ⊆ V of items. When the store sells an item i ∈ V at the price ri, the profit for the item i is pi = ri - di. The goal of the store is to decide the price of each item to maximize its total profit. We refer to this maximization problem as the item pricing problem. In most of the previous works, the item pricing problem was considered under the assumption that pi ≥ 0 for each i ∈ V, however, Balcan, et al. [In Proc. of WINE, LNCS 4858, 2007] introduced the notion of “loss-leader, ” and showed that the seller can get more total profit in the case that pi < 0 is allowed than in the case that pi < 0 is not allowed. In this paper, we derive approximation preserving reductions among several item pricing problems and show that all of them have algorithms with good approximation ratio.
Full Text Available In this paper a modern item design framework for computer based assessment based on Flash authoring environment will be introduced. Question design will be discussed as well as the multimedia authoring environment used for item modeling emphasized. Item type templates are a structured means of collecting and storing item information that can be used to improve the efficiency and security of the innovative item design process. Templates can modernize the item design, enhance and speed up the development process. Along with content creation, multimedia has vast potential for use in innovative testing. The introduced item design template is based on taxonomy of innovative items which have great potential for expanding the content areas and construct coverage of an assessment. The presented item design approach is based on GUI's – one for question design based on implemented item design templates and one for user interaction tracking/retrieval. The concept of user interfaces based on Flash technology will be discussed as well as implementation of the innovative approach of the item design forms with multimedia authoring. Also an innovative method for user interaction storage/retrieval based on PHP extending Flash capabilities in the proposed framework will be introduced.
J. van Hoof PhD
Full Text Available Introduction: Losing items is a time-consuming occurrence in nursing homes that is ill described. An explorative study was conducted to investigate which items got lost by nursing home residents, and how this affects the residents and family caregivers. Method: Semi-structured interviews and card sorting tasks were conducted with 12 residents with early-stage dementia and 12 family caregivers. Thematic analysis was applied to the outcomes of the sessions. Results: The participants stated that numerous personal items and assistive devices get lost in the nursing home environment, which had various emotional, practical, and financial implications. Significant amounts of time are spent on trying to find items, varying from 1 hr up to a couple of weeks. Numerous potential solutions were identified by the interviewees. Discussion: Losing items often goes together with limitations to the participation of residents. Many family caregivers are reluctant to replace lost items, as these items may get lost again.
Scheuneman, Janice Dowd; Gerritz, Kalle
Differential item functioning (DIF) methodology for revealing sources of item difficulty and performance characteristics of different groups was explored. A total of 150 Scholastic Aptitude Test items and 132 Graduate Record Examination general test items were analyzed. DIF was evaluated for males and females and Blacks and Whites. (SLD)
Gierl, Mark J.; Lai, Hollis
Changes to the design and development of our educational assessments are resulting in the unprecedented demand for a large and continuous supply of content-specific test items. One way to address this growing demand is with automatic item generation (AIG). AIG is the process of using item models to generate test items with the aid of computer…
CERN Running club
The CERN Running Club is organising a sale of items on 26 June from 11:30 – 13:00 in the entry area of Restaurant 2 (504 R-202). The items for sale are souvenir prizes of past Relay Races and comprise: Backpacks, thermos, towels, gloves & caps, lamps, long sleeve winter shirts and windproof vest. All items will be sold at 5 CHF.
Yau, David T W; Wong, May C M; Lam, K F; McGrath, Colman
Four-factor structure of the two 8-item short forms of Child Perceptions Questionnaire CPQ11-14 (RSF:8 and ISF:8) has been confirmed. However, the sum scores are typically reported in practice as a proxy of Oral health-related Quality of Life (OHRQoL), which implied a unidimensional structure. This study first assessed the unidimensionality of 8-item short forms of CPQ11-14. Item response theory (IRT) was employed to offer an alternative and complementary approach of validation and to overcome the limitations of classical test theory assumptions. A random sample of 649 12-year-old school children in Hong Kong was analyzed. Unidimensionality of the scale was tested by confirmatory factor analysis (CFA), principle component analysis (PCA) and local dependency (LD) statistic. Graded response model was fitted to the data. Contribution of each item to the scale was assessed by item information function (IIF). Reliability of the scale was assessed by test information function (TIF). Differential item functioning (DIF) across gender was identified by Wald test and expected score functions. Both CPQ11-14 RSF:8 and ISF:8 did not deviate much from the unidimensionality assumption. Results from CFA indicated acceptable fit of the one-factor model. PCA indicated that the first principle component explained >30 % of the total variation with high factor loadings for both RSF:8 and ISF:8. Almost all LD statistic items suggesting little contribution of information to the scale and item removal caused little practical impact. Comparing the TIFs, RSF:8 showed slightly better information than ISF:8. In addition to oral symptoms items, the item "Concerned with what other people think" demonstrated a uniform DIF (p Items related to oral symptoms were not informative to OHRQoL and deletion of these items is suggested. The impact of DIF across gender on the overall score was minimal. CPQ11-14 RSF:8 performed slightly better than ISF:8 in measurement precision. The 6-item short forms
... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Transportation items. 3... Burial Benefits § 3.1606 Transportation items. The transportation costs of those persons who come within... shipment. (6) Cost of transportation by common carrier including amounts paid as Federal taxes. (7) Cost of...
Mavletova, Aigul; Couper, Mick P.
There is some evidence that a scrolling design may reduce breakoffs in mobile web surveys compared to a paging design, but there is little empirical evidence to guide the choice of the optimal number of items per page. We investigate the effect of the number of items presented on a page on data quality in two types of questionnaires: with or…
van der Linden, Willem J.
In choosing a binomial test model, it is important to know exactly what conditions are imposed on item difficulty. In this paper these conditions are examined for both a deterministic and a stochastic conception of item responses. It appears that they are more restrictive than is generally
Angel, Jais Andreas Breusch; De Chiffre, Leonardo
In a comparison involving 27 laboratories from 8 countries, measurements on two common industrial items, a polymer part and a metal part, were carried out using X-ray Computed Tomography. All items were measured using coordinate measuring machines before and after circulation, with reference...
Messinger, H B; Messinger, M I
Recently in this journal Peters and Murphy challenged the validity of factor analyses done on bimodal handedness data, suggesting instead that right- and left-handers be studied separately. But bimodality may be avoidable if attention is paid to Oldfield's questionnaire format and instructions for the subjects. Two characteristics appear crucial: a two-column LEFT-RIGHT format for the body of the instrument and what we call Oldfield's Admonition: not to indicate strong preference for handedness item, such as write, unless "... the preference is so strong that you would never try to use the other hand unless absolutely forced to...". Attaining unimodality of an item distribution would seem to overcome the objections of Peters and Murphy. In a 1984 survey in Boston we used Oldfield's ten-item questionnaire exactly as published. This produced unimodal item distributions. With reflection of the five-point item scale and a logarithmic transformation, we achieved a degree of normalization for the items. Two surveys elsewhere based on Oldfield's 20-item list but with changes in the questionnaire format and the instructions, yielded markedly different item distributions with peaks at each extreme and sometimes in the middle as well.
Engelen, Ron J.H.; van der Linden, Willem J.; Oosterloo, Sebe J.
Fisher's information measure for the item difficulty parameter in the Rasch model and its marginal and conditional formulations are investigated. It is shown that expected item information in the unconditional model equals information in the marginal model, provided the assumption of sampling
Background/Purpose: Constipation in children is considered when stool frequency is less than three times per week. Encopresis represents 80-90% of children with fecal incontinence. Operative strategy for management of encopresis ranges from resectional surgery to myotomy. The objective of the study was to evaluate ...
Nov 13, 2017 ... In the reversible case, these inequalities were obtained by. Cavalletti and ... active area. The classical Riemannian theory has been generalized to weighted Rieman- .... Define the dual Minkowski norm F. ∗: T. ∗ .... We also define Ric∞(v) and Ricn(v) as the limits and set RicN (cv) := c2RicN (v) for c ≥ 0.
Nunes, Sandra; Oliveira, Teresa; Oliveira, Amílcar
The Item Response Theory (IRT) has become one of the most popular scoring frameworks for measurement data, frequently used in computerized adaptive testing, cognitively diagnostic assessment and test equating. According to Andrade et al. (2000), IRT can be defined as a set of mathematical models (Item Response Models - IRM) constructed to represent the probability of an individual giving the right answer to an item of a particular test. The number of Item Responsible Models available to measurement analysis has increased considerably in the last fifteen years due to increasing computer power and due to a demand for accuracy and more meaningful inferences grounded in complex data. The developments in modeling with Item Response Theory were related with developments in estimation theory, most remarkably Bayesian estimation with Markov chain Monte Carlo algorithms (Patz & Junker, 1999). The popularity of Item Response Theory has also implied numerous overviews in books and journals, and many connections between IRT and other statistical estimation procedures, such as factor analysis and structural equation modeling, have been made repeatedly (Van der Lindem & Hambleton, 1997). As stated before the Item Response Theory covers a variety of measurement models, ranging from basic one-dimensional models for dichotomously and polytomously scored items and their multidimensional analogues to models that incorporate information about cognitive sub-processes which influence the overall item response process. The aim of this work is to introduce the main concepts associated with one-dimensional models of Item Response Theory, to specify the logistic models with one, two and three parameters, to discuss some properties of these models and to present the main estimation procedures.
DeMars, Christine E.; Jurich, Daniel P.
The nonequivalent groups anchor test (NEAT) design is often used to scale item parameters from two different test forms. A subset of items, called the anchor items or common items, are administered as part of both test forms. These items are used to adjust the item calibrations for any differences in the ability distributions of the groups taking…
For a randomly renewed item the probability distributions of the time to failure and of the duration of down time and the expectations of these random variables are determined. Moreover, it is shown that the same theory applies to randomly checked items with exponential probability distribution of life such as electronic items. The case of periodic renewals is treated as an example. (orig.) [de
Aybek, Eren Can; Demirtasli, R. Nukhet
This article aims to provide a theoretical framework for computerized adaptive tests (CAT) and item response theory models for polytomous items. Besides that, it aims to introduce the simulation and live CAT software to the related researchers. Computerized adaptive test algorithm, assumptions of item response theory models, nominal response…
Bichi, Ado Abdu; Hafiz, Hadiza; Bello, Samira Abdullahi
High-stakes testing is used for the purposes of providing results that have important consequences. Validity is the cornerstone upon which all measurement systems are built. This study applied the Item Response Theory principles to analyse Northwest University Kano Post-UTME Economics test items. The developed fifty (50) economics test items was…
Cher Wong, Cheow
Building on previous works by Lord and Ogasawara for dichotomous items, this article proposes an approach to derive the asymptotic standard errors of item response theory true score equating involving polytomous items, for equivalent and nonequivalent groups of examinees. This analytical approach could be used in place of empirical methods like…
Sahin, Alper; Anil, Duygu
This study investigates the effects of sample size and test length on item-parameter estimation in test development utilizing three unidimensional dichotomous models of item response theory (IRT). For this purpose, a real language test comprised of 50 items was administered to 6,288 students. Data from this test was used to obtain data sets of…
Arce-Ferrer, Alvaro J.; Bulut, Okan
This study examines separate and concurrent approaches to combine the detection of item parameter drift (IPD) and the estimation of scale transformation coefficients in the context of the common item nonequivalent groups design with the three-parameter item response theory equating. The study uses real and synthetic data sets to compare the two…
Siskind, Theresa G.; Anderson, Lorin W.
The study was designed to examine the similarity of response options generated by different item writers using a systematic approach to item writing. The similarity of response options to student responses for the same item stems presented in an open-ended format was also examined. A non-systematic (subject matter expertise) approach and a…
von Davier, Matthias
Utilizing technology for automated item generation is not a new idea. However, test items used in commercial testing programs or in research are still predominantly written by humans, in most cases by content experts or professional item writers. Human experts are a limited resource and testing agencies incur high costs in the process of continuous renewal of item banks to sustain testing programs. Using algorithms instead holds the promise of providing unlimited resources for this crucial part of assessment development. The approach presented here deviates in several ways from previous attempts to solve this problem. In the past, automatic item generation relied either on generating clones of narrowly defined item types such as those found in language free intelligence tests (e.g., Raven's progressive matrices) or on an extensive analysis of task components and derivation of schemata to produce items with pre-specified variability that are hoped to have predictable levels of difficulty. It is somewhat unlikely that researchers utilizing these previous approaches would look at the proposed approach with favor; however, recent applications of machine learning show success in solving tasks that seemed impossible for machines not too long ago. The proposed approach uses deep learning to implement probabilistic language models, not unlike what Google brain and Amazon Alexa use for language processing and generation.
U.S. Department of Health & Human Services — The National Health Related Items Code (NHRIC) is a system for identification and numbering of marketed device packages that is compatible with other numbering...
U.S. Department of Health & Human Services — This release contains the Basic Stand Alone (BSA) Carrier Line Items Public Use Files (PUF) with information from Medicare Carrier claims. The CMS BSA Carrier Line...
Full Text Available Item response theory (IRT becomes an increasingly important tool when analyzing “big data” gathered from online educational venues. However, the mechanism was originally developed in traditional exam settings, and several of its assumptions are infringed upon when deployed in the online realm. For a large-enrollment physics course for scientists and engineers, the study compares outcomes from IRT analyses of exam and homework data, and then proceeds to investigate the effects of each confounding factor introduced in the online realm. It is found that IRT yields the correct trends for learner ability and meaningful item parameters, yet overall agreement with exam data is moderate. It is also found that learner ability and item discrimination is robust over a wide range with respect to model assumptions and introduced noise. Item difficulty is also robust, but over a narrower range.
Although a GUI largely replaces textual descriptions by graphical icons, the textual items are not completely removed. The textual items are inevitably used in window titles, message boxes, help items, menu items and popup items. Textual items are necessary for communicating messages that are beyond the limitation of graphical messages. However, it is necessary to harness the textual items on the graphical interface in such a way that they complement each other to produce the best effect. One...
With reference to a questionnaire that aimed to assess the quality of life for dysarthric speakers, we investigate the usefulness of a model-based procedure for reducing the number of items. We propose a mixed cumulative logit model, which is known in the psychometrics literature as the graded response model: responses to different items are modelled as a function of individual latent traits and as a function of item characteristics, such as their difficulty and their discrimination power. We jointly model the discrimination and the difficulty parameters by using a k-component mixture of normal distributions. Mixture components correspond to disjoint groups of items. Items that belong to the same groups can be considered equivalent in terms of both difficulty and discrimination power. According to decision criteria, we select a subset of items such that the reduced questionnaire is able to provide the same information that the complete questionnaire provides. The model is estimated by using a Bayesian approach, and the choice of the number of mixture components is justified according to information criteria. We illustrate the proposed approach on the basis of data that are collected for 104 dysarthric patients by local health authorities in Lecce and in Milan. Copyright © 2014 John Wiley & Sons, Ltd.
Ana R Quiñones
Full Text Available Objectives: Optimal depression screening necessitates measurement tools that are valid across varied populations and in the presence of comorbidities. Methods: This study assessed the test properties of two versions of the Center for Epidemiologic Studies Depression scale against psychiatric diagnoses established by the Mini International Neuropsychiatric Interview among a clinical sample of US Veterans deployed during Operations Enduring Freedom, Iraqi Freedom, and New Dawn. Participants (N = 359 recruited from two Department of Veterans Affairs hospitals completed a clinical interview, structured diagnostic interview, and self-reported measures. Results: Based on diagnostic interview and the Diagnostic and Statistical Manual of Mental Disorders 4th Edition criteria, 29.5% of the sample met diagnostic criteria for major depressive disorder and 26.5% met diagnostic criteria for post-traumatic stress disorder. Both Center for Epidemiologic Studies Depression-20 and Center for Epidemiologic Studies Depression-10 scales performed well and almost identically against the Mini International Neuropsychiatric Interview-major depressive disorder in identifying Veterans with major depressive disorder (Center for Epidemiologic Studies Depression-20 area under the Receiver Operating Characteristic curve 91%; Center for Epidemiologic Studies Depression-10 area under the ROC curve 90%. Overall, higher cut points for the Center for Epidemiologic Studies Depression scales performed better in correctly identifying true positives and true negatives for major depressive disorder (Center for Epidemiologic Studies Depression-20 cut point 18+ sensitivity 92% specificity 72%; Center for Epidemiologic Studies Depression-10 cut point 10+ sensitivity 92% specificity 69%. Conclusions: The specificity of the Center for Epidemiologic Studies Depression scales was poor among Veterans with co-occurring post-traumatic stress disorder (13% and 16%. Veterans with post-traumatic stress disorder who have a positive depression screen should have a more thorough assessment of mental health symptoms and comorbidities, rather than immediate diagnosis of and treatment for depression.
Peterson, Dwight J; Naveh-Benjamin, Moshe
An important yet unresolved question regarding visual working memory (VWM) relates to whether or not binding processes within VWM require additional attentional resources compared with processing solely the individual components comprising these bindings. Previous findings indicate that binding of surface features (e.g., colored shapes) within VWM is not demanding of resources beyond what is required for single features. However, it is possible that other types of binding, such as the binding of complex, distinct items (e.g., faces and scenes), in VWM may require additional resources. In 3 experiments, we examined VWM item-item binding performance under no load, articulatory suppression, and backward counting using a modified change detection task. Binding performance declined to a greater extent than single-item performance under higher compared with lower levels of concurrent load. The findings from each of these experiments indicate that processing item-item bindings within VWM requires a greater amount of attentional resources compared with single items. These findings also highlight an important distinction between the role of attention in item-item binding within VWM and previous studies of long-term memory (LTM) where declines in single-item and binding test performance are similar under divided attention. The current findings provide novel evidence that the specific type of binding is an important determining factor regarding whether or not VWM binding processes require attention. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Park, Yoon Soo; Lee, Young-Sun; Xing, Kuan
This study investigates the impact of item parameter drift (IPD) on parameter and ability estimation when the underlying measurement model fits a mixture distribution, thereby violating the item invariance property of unidimensional item response theory (IRT) models. An empirical study was conducted to demonstrate the occurrence of both IPD and an underlying mixture distribution using real-world data. Twenty-one trended anchor items from the 1999, 2003, and 2007 administrations of Trends in International Mathematics and Science Study (TIMSS) were analyzed using unidimensional and mixture IRT models. TIMSS treats trended anchor items as invariant over testing administrations and uses pre-calibrated item parameters based on unidimensional IRT. However, empirical results showed evidence of two latent subgroups with IPD. Results also showed changes in the distribution of examinee ability between latent classes over the three administrations. A simulation study was conducted to examine the impact of IPD on the estimation of ability and item parameters, when data have underlying mixture distributions. Simulations used data generated from a mixture IRT model and estimated using unidimensional IRT. Results showed that data reflecting IPD using mixture IRT model led to IPD in the unidimensional IRT model. Changes in the distribution of examinee ability also affected item parameters. Moreover, drift with respect to item discrimination and distribution of examinee ability affected estimates of examinee ability. These findings demonstrate the need to caution and evaluate IPD using a mixture IRT framework to understand its effects on item parameters and examinee ability.
Yoon Soo ePark
Full Text Available This study investigates the impact of item parameter drift (IPD on parameter and ability estimation when the underlying measurement model fits a mixture distribution, thereby violating the item invariance property of unidimensional item response theory (IRT models. An empirical study was conducted to demonstrate the occurrence of both IPD and an underlying mixture distribution using real-world data. Twenty-one trended anchor items from the 1999, 2003, and 2007 administrations of Trends in International Mathematics and Science Study (TIMSS were analyzed using unidimensional and mixture IRT models. TIMSS treats trended anchor items as invariant over testing administrations and uses pre-calibrated item parameters based on unidimensional IRT. However, empirical results showed evidence of two latent subgroups with IPD. Results showed changes in the distribution of examinee ability between latent classes over the three administrations. A simulation study was conducted to examine the impact of IPD on the estimation of ability and item parameters, when data have underlying mixture distributions. Simulations used data generated from a mixture IRT model and estimated using unidimensional IRT. Results showed that data reflecting IPD using mixture IRT model led to IPD in the unidimensional IRT model. Changes in the distribution of examinee ability also affected item parameters. Moreover, drift with respect to item discrimination and distribution of examinee ability affected estimates of examinee ability. These findings demonstrate the need to caution and evaluate IPD using a mixture IRT framework to understand its effect on item parameters and examinee ability.
Fenwick, Eva K; Pesudovs, Konrad; Khadka, Jyoti; Rees, Gwyn; Wong, Tien Y; Lamoureux, Ecosse L
We are developing an item bank assessing the impact of diabetic retinopathy (DR) on quality of life (QoL) using a rigorous multi-staged process combining qualitative and quantitative methods. We describe here the first two qualitative phases: content development and item evaluation. After a comprehensive literature review, items were generated from four sources: (1) 34 previously validated patient-reported outcome measures; (2) five published qualitative articles; (3) eight focus groups and 18 semi-structured interviews with 57 DR patients; and (4) seven semi-structured interviews with diabetes or ophthalmic experts. Items were then evaluated during 3 stages, namely binning (grouping) and winnowing (reduction) based on key criteria and panel consensus; development of item stems and response options; and pre-testing of items via cognitive interviews with patients. The content development phase yielded 1,165 unique items across 7 QoL domains. After 3 sessions of binning and winnowing, items were reduced to a minimally representative set (n = 312) across 9 domains of QoL: visual symptoms; ocular surface symptoms; activity limitation; mobility; emotional; health concerns; social; convenience; and economic. After 8 cognitive interviews, 42 items were amended resulting in a final set of 314 items. We have employed a systematic approach to develop items for a DR-specific QoL item bank. The psychometric properties of the nine QoL subscales will be assessed using Rasch analysis. The resulting validated item bank will allow clinicians and researchers to better understand the QoL impact of DR and DR therapies from the patient's perspective.
Penfield, Randall David
A polytomous item is one for which the responses are scored according to three or more categories. Given the increasing use of polytomous items in assessment practices, item response theory (IRT) models specialized for polytomous items are becoming increasingly common. The purpose of this ITEMS module is to provide an accessible overview of…
A loglinear item response theory (IRT) model is proposed that relates polytomously scored item responses to a multidimensional latent space. Each item may have a different response function where each item response may be explained by one or more latent traits. Item response functions may follow a
Ariel, A.; van der Linden, Willem J.; Veldkamp, Bernard P.
Item-pool management requires a balancing act between the input of new items into the pool and the output of tests assembled from it. A strategy for optimizing item-pool management is presented that is based on the idea of a periodic update of an optimal blueprint for the item pool to tune item
This presentation (slides) provides an overview of the industry's challenges and activities. Firstly, it outlines the differences between counterfeit, fraudulent, suspect, and also substandard items. Notice is given that items could be found not to meet the standard, but the difference in the intent to deceive with counterfeit and fraudulent items is the critical element. Examples from other industries are used which also rely heavily on the assurance of quality for safety. It also informs that EPRI has just completed a report in October 2009 in coordination with other US government agencies and industry organizations; this report, entitled Counterfeit, Substandard and Fraudulent Items, number 1019163, is available for free on the EPRI web site. As a follow-up to this report, EPRI is developing a CFSI Database; any country interested in a collaborative agreement is invited to use and contribute to the database information. Finally, it stresses the importance of the oversight of contractors, training to raise the awareness of the employees and the inspectors, and having a response plan for identified items
This study investigated test item bias and Differential Item Functioning (DIF) of West African ... items in chemistry function differentially with respect to gender and location. In Aba education zone of Abia, 50 secondary schools were purposively ...
fed set ofvaluesof a, b, AI , B1 A2 2 . 2 A3 , and 13 , the f ’. g ’a. nd h’a in (7) are fied. Equation (7) must still hold for S - e19029e3,..* . Thus...for Item I Is -- b ?(a:1 , b1 ,O) (1 + ’)(I + e4 (22 where a and pi are arbitrary constants. These constants mst be the sam for all Items In a given...NETHERLIS I E3I1 Focility-Acquisitions 4133 Rugby Avnue 1 Lee Cronbach Bethesda, NO 20014 16 Laburnue Road Atherton, CA 94205 1 Dr. Benjamin A. Fairbank
Khawaja, Nigar G.; Yu, Lai Ngo Heidi
The 27-item Intolerance of Uncertainty Scale (IUS) has become one of the most frequently used measures of Intolerance of Uncertainty. More recently, an abridged, 12-item version of the IUS has been developed. The current research used clinical (n = 50) and non-clinical (n = 56) samples to examine and compare the psychometric properties of both…
Fischer, H Felix; Wahl, Inka; Nolte, Sandra; Liegl, Gregor; Brähler, Elmar; Löwe, Bernd; Rose, Matthias
To investigate differential item functioning (DIF) of PROMIS Depression items between US and German samples we compared data from the US PROMIS calibration sample (n = 780), a German general population survey (n = 2,500) and a German clinical sample (n = 621). DIF was assessed in an ordinal logistic regression framework, with 0.02 as criterion for R 2 -change and 0.096 for Raju's non-compensatory DIF. Item parameters were initially fixed to the PROMIS Depression metric; we used plausible values to account for uncertainty in depression estimates. Only four items showed DIF. Accounting for DIF led to negligible effects for the full item bank as well as a post hoc simulated computer-adaptive test (German general population sample was considerably lower compared to the US reference value of 50. Overall, we found little evidence for language DIF between US and German samples, which could be addressed by either replacing the DIF items by items not showing DIF or by scoring the short form in German samples with the corrected item parameters reported. Copyright © 2016 John Wiley & Sons, Ltd.
Baghaei, Purya; Ravand, Hamdollah
In this study the magnitudes of local dependence generated by cloze test items and reading comprehension items were compared and their impact on parameter estimates and test precision was investigated. An advanced English as a foreign language reading comprehension test containing three reading passages and a cloze test was analyzed with a…
Petersen, Morten Aa.; Gamper, Eva-Maria; Costantini, Anna
of the widely used EORTC Quality of Life questionnaire (QLQ-C30). STUDY DESIGN AND SETTING: On the basis of literature search and evaluations by international samples of experts and cancer patients, 38 candidate items were developed. The psychometric properties of the items were evaluated in a large...... international sample of cancer patients. This included evaluations of dimensionality, item response theory (IRT) model fit, differential item functioning (DIF), and of measurement precision/statistical power. RESULTS: Responses were obtained from 1,023 cancer patients from four countries. The evaluations showed...... that 24 items could be included in a unidimensional IRT model. DIF did not seem to have any significant impact on the estimation of EF. Evaluations indicated that the CAT measure may reduce sample size requirements by up to 50% compared to the QLQ-C30 EF scale without reducing power. CONCLUSION...
Kleinman, Marjorie; Teresi, Jeanne A
Measures of magnitude and impact of differential item functioning (DIF) at the item and scale level, respectively are presented and reviewed in this paper. Most measures are based on item response theory models. Magnitude refers to item level effect sizes, whereas impact refers to differences between groups at the scale score level. Reviewed are magnitude measures based on group differences in the expected item scores and impact measures based on differences in the expected scale scores. The similarities among these indices are demonstrated. Various software packages are described that provide magnitude and impact measures, and new software presented that computes all of the available statistics conveniently in one program with explanations of their relationships to one another.
... FOR TELECOMMUNICATIONS COMPANIES Instructions For Other Income Accounts § 32.7600 Extraordinary items... extraordinary. Extraordinary events and transactions are distinguished by both their unusual nature and by the infrequency of their occurrence, taking into account the environment in which the company operates. This...
Holland, Wade B.
An issue of "Soviet Cybernetics: Recent News Items" consists of English translations of the leading recent Soviet contributions to the study of cybernetics. Articles deal with cybernetics in the 21st Century; the Soviet State Committee on Science and Technology; economic reforms in Rudnev's ministry; an interview with Rudnev; Dnepr-2; Dnepr-2…
Multani, Namita; Rudzicz, Frank; Wong, Wing Yiu Stephanie; Namasivayam, Aravind Kumar; van Lieshout, Pascal
Purpose: Random item generation (RIG) involves central executive functioning. Measuring aspects of random sequences can therefore provide a simple method to complement other tools for cognitive assessment. We examine the extent to which RIG relates to specific measures of cognitive function, and whether those measures can be estimated using RIG…
Russell, Thyra K.
Morris Library at Southern Illinois University computerized its technical processes using the Library Computer System (LCS), which was implemented in the library to streamline order processing by: (1) providing up-to-date online files to track in-process items; (2) encouraging quick, efficient accessing of information; (3) reducing manual files;…
van der Linden, Willem J.; Adema, Jos J.
Two optimalization models for the construction of tests with a maximal value of coefficient alpha are given. Both models have a linear form and can be solved by using a branch-and-bound algorithm. The first model assumes an item bank calibrated under the Rasch model and can be used, for instance,
Freeman, Emily; Heathcote, Andrew; Chalmers, Kerry; Hockley, William
We investigate the effects of word characteristics on episodic recognition memory using analyses that avoid Clark's (1973) "language-as-a-fixed-effect" fallacy. Our results demonstrate the importance of modeling word variability and show that episodic memory for words is strongly affected by item noise (Criss & Shiffrin, 2004), as measured by the…
Item response theory (IRT) becomes an increasingly important tool when analyzing "big data" gathered from online educational venues. However, the mechanism was originally developed in traditional exam settings, and several of its assumptions are infringed upon when deployed in the online realm. For a large-enrollment physics course for…
With the development in computing technology, item response theory (IRT) develops rapidly, and has become a user friendly application in psychometrics world. Limitation in classical theory is one aspect that encourages the use of IRT. In this study, the basic concept of IRT will be discussed. In addition, it will briefly review the ability…
Uto, Masaki; Ueno, Maomi
As an assessment method based on a constructivist approach, peer assessment has become popular in recent years. However, in peer assessment, a problem remains that reliability depends on the rater characteristics. For this reason, some item response models that incorporate rater parameters have been proposed. Those models are expected to improve…
... DEPARTMENT OF DEFENSE Defense Acquisition Regulations System 48 CFR Part 212 Acquisition of Commercial Items CFR Correction 212.504 [Corrected] In Title 48 of the Code of Federal Regulations, Chapter 2 (Parts 201--299), revised as of October 1, 2011, on page 73, in section 212.504, paragraph (a) is...
van der Linden, Willem J.
R.J. Owen (1975) proposed an approximate empirical Bayes procedure for item selection in adaptive testing. The procedure replaces the true posterior by a normal approximation with closed-form expressions for its first two moments. This approximation was necessary to minimize the computational
Voskuilen, Chelsea; Ratcliff, Roger; McKoon, Gail
We examined the effects of aging on performance in an item-recognition experiment with confidence judgments. A model for confidence judgments and response time (RTs; Ratcliff & Starns, 2013) was used to fit a large amount of data from a new sample of older adults and a previously reported sample of younger adults. This model of confidence…
... Quantities of Strategic Special Nuclear Material § 74.55 Item monitoring. (a) Licensees subject to § 74.51... quantitatively measured, the validity of that measurement independently confirmed, and that additionally have..., except for reactor components measuring at least one meter in length and weighing in excess of 30...
Clark, Brian; Stierman, John
Librarians build collections. To do this they use tools that help them identify, organize, and retrieve items for the collection. Zotero (zoh-TAIR-oh) is such a tool that helps the user build a library of useful books, articles, web sites, blogs, etc., discovered while surfing online. A visit to Zotero's homepage, www.zotero.org, shows a number of…
Obbarius, Nina; Fischer, Felix; Obbarius, Alexander; Nolte, Sandra; Liegl, Gregor; Rose, Matthias
To develop the first item bank to measure Stress Resilience (SR) in clinical populations. Qualitative item development resulted in an initial pool of 131 items covering a broad theoretical SR concept. These items were tested in n=521 patients at a psychosomatic outpatient clinic. Exploratory and Confirmatory Factor Analysis (CFA), as well as other state-of-the-art item analyses and IRT were used for item evaluation and calibration of the final item bank. Out of the initial item pool of 131 items, we excluded 64 items (54 factor loading .3, 2 non-discriminative Item Response Curves, 4 Differential Item Functioning). The final set of 67 items indicated sufficient model fit in CFA and IRT analyses. Additionally, a 10-item short form with high measurement precision (SE≤.32 in a theta range between -1.8 and +1.5) was derived. Both the SR item bank and the SR short form were highly correlated with an existing static legacy tool (Connor-Davidson Resilience Scale). The final SR item bank and 10-item short form showed good psychometric properties. When further validated, they will be ready to be used within a framework of Computer-Adaptive Tests for a comprehensive assessment of the Stress-Construct. Copyright © 2018. Published by Elsevier Inc.
Johnson, Matthew S.; Sinharay, Sandip
For complex educational assessments, there is an increasing use of "item families," which are groups of related items. However, calibration or scoring for such an assessment requires fitting models that take into account the dependence structure inherent among the items that belong to the same item family. C. Glas and W. van der Linden…
Williamson, David M.; Johnson, Matthew S.; Sinharay, Sandip; Bejar, Isaac I.
This study explored the application of hierarchical model calibration as a means of reducing, if not eliminating, the need for pretesting of automatically generated items from a common item model prior to operational use. Ultimately the successful development of automatic item generation (AIG) systems capable of producing items with highly similar…
... 10 Energy 4 2010-01-01 2010-01-01 false Labeling items and containers. 835.605 Section 835.605... items and containers. Except as provided at § 835.606, each item or container of radioactive material... information to permit individuals handling, using, or working in the vicinity of the items or containers to...
... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true Review of items. 101-27.404 Section 101-27.404 Public Contracts and Property Management Federal Property Management...-Elimination of Items From Inventory § 101-27.404 Review of items. Except for standby or reserve stocks, items...
Commons, C., Ed.; Martin, P., Ed.
Volume 1 of the Australian Chemistry Test Item Bank, consisting of two volumes, contains nearly 2000 multiple-choice items related to the chemistry taught in Year 11 and Year 12 courses in Australia. Items which were written during 1979 and 1980 were initially published in the "ACER Chemistry Test Item Collection" and in the "ACER…
Australian Council for Educational Research, Hawthorn.
The chemistry test item banks contains 225 multiple-choice questions suitable for diagnostic and achievement testing; a three-page teacher's guide; answer key with item facilities; an answer sheet; and a 45-item sample achievement test. Although written for the new grade 12 chemistry course in Victoria, Australia, the items are widely applicable.…
Fan, Zhewen; Wang, Chun; Chang, Hua-Hua; Douglas, Jeffrey
Traditional methods for item selection in computerized adaptive testing only focus on item information without taking into consideration the time required to answer an item. As a result, some examinees may receive a set of items that take a very long time to finish, and information is not accrued as efficiently as possible. The authors propose two…
French, Christine L.
Item analysis is a very important consideration in the test development process. It is a statistical procedure to analyze test items that combines methods used to evaluate the important characteristics of test items, such as difficulty, discrimination, and distractibility of the items in a test. This paper reviews some of the classical methods for…
Nov 5, 2014 ... Key words: Classical test theory, item analysis, item difficulty, item discrimination, item response theory, reliability ... the probability of answering an item correctly or of attaining ..... A Monte Carlo comparison of item and person.
The West Valley Demonstration Project, located on the site of the only commercial nuclear fuel reprocessing facility to have operated in USA, has the directed objectives of solidifying the high-level radioactive waste into a durable, solid form for shipment; decontaminating and decommissioning the tanks and facilities; and disposing of the resulting low-level and transuranic wastes. Since an escalating trend of open work items was noticed in the Fall of 1988, and there was no control mechanism for tracking and closing the open items, a Work Control System was developed for this purpose. It is self-contained system on a mainframe ARTEMIS 9000, which tracks, monitors, and closes out external commitments in a timely manner. Audits, surveillances, site appraisals, preventive maintenance, instrument calibration recall, and scheduling are covered
Norman D. Verhelst
Full Text Available This study discusses the justifiability of item parameter estimation in incomplete testing designs in item response theory. Marginal maximum likelihood (MML as well as conditional maximum likelihood (CML procedures are considered in three commonly used incomplete designs: random incomplete, multistage testing and targeted testing designs. Mislevy and Sheenan (1989 have shown that in incomplete designs the justifiability of MML can be deduced from Rubin's (1976 general theory on inference in the presence of missing data. Their results are recapitulated and extended for more situations. In this study it is shown that for CML estimation the justification must be established in an alternative way, by considering the neglected part of the complete likelihood. The problems with incomplete designs are not generally recognized in practical situations. This is due to the stochastic nature of the incomplete designs which is not taken into account in standard computer algorithms. For that reason, incorrect uses of standard MML- and CML-algorithms are discussed.
Skinner, Erin I; Fernandes, Myra A
We examined how visual context information provided during encoding, and unrelated to the target word, affected later recollection for words presented alone using a remember-know paradigm. Experiments 1A and 1B showed that participants had better overall memory-specifically, recollection-for words studied with pictures of intact faces than for words studied with pictures of scrambled or inverted faces. Experiment 2 replicated these results and showed that recollection was higher for words studied with pictures of faces than when no image accompanied the study word. In Experiment 3 participants showed equivalent memory for words studied with unique faces as for those studied with a repeatedly presented face. Results suggest that recollection benefits when visual context information high in meaningful content accompanies study words and that this benefit is not related to the uniqueness of the context. We suggest that participants use elaborative processes to integrate item and meaningful contexts into ensemble information, improving subsequent item recollection.
... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Inclusion of items, differentiation between items and answers, omission of instructions. 260.7a-16 Section 260.7a-16 Commodity and... INDENTURE ACT OF 1939 Formal Requirements § 260.7a-16 Inclusion of items, differentiation between items and...
Full Text Available BACKGROUND: Integration of information streams into a unitary representation is an important task of our cognitive system. Within working memory, the medial temporal lobe (MTL has been conceptually linked to the maintenance of bound representations. In a previous fMRI study, we have shown that the MTL is indeed more active during working-memory maintenance of spatial associations as compared to non-spatial associations or single items. There are two explanations for this result, the mere presence of the spatial component activates the MTL, or the MTL is recruited to bind associations between neurally non-overlapping representations. METHODOLOGY/PRINCIPAL FINDINGS: The current fMRI study investigates this issue further by directly comparing intrinsic intra-item binding (object/colour, extrinsic intra-item binding (object/location, and inter-item binding (object/object. The three binding conditions resulted in differential activation of brain regions. Specifically, we show that the MTL is important for establishing extrinsic intra-item associations and inter-item associations, in line with the notion that binding of information processed in different brain regions depends on the MTL. CONCLUSIONS/SIGNIFICANCE: Our findings indicate that different forms of working-memory binding rely on specific neural structures. In addition, these results extend previous reports indicating that the MTL is implicated in working-memory maintenance, challenging the classic distinction between short-term and long-term memory systems.
Lei, Pui-Wa; Wu, Qiong
This article describes the functions of a SAS macro and an SPSS syntax that produce common statistics for conventional item analysis including Cronbach's alpha, item difficulty index (p-value or item mean), and item discrimination indices (D-index, point biserial and biserial correlations for dichotomous items and item-total correlation for polytomous items). These programs represent an improvement over the existing SAS and SPSS item analysis routines in terms of completeness and user-friendliness. To promote routine evaluations of item qualities in instrument development of any scale, the programs are available at no charge for interested users. The program codes along with a brief user's manual that contains instructions and examples are downloadable from suen.ed.psu.edu/-pwlei/plei.htm.
Full Text Available Construction logistics are activities that consist of ordering, storage and transportation of materials of construction projects. Storage material is logistics activity that ensure the availability of materials in project site. Generally, material storage activities have been conducted at the project site. Logistics construction is aimed to support the project activities that the completion schedule has been set. Construction logistics issues is determining the schedule of ordering materials so that the project can be implemented on schedule. The purpose of research is to determine the optimum ordering period for the primary items on the main building structure construction and designing inventory control cards as a mechanism for monitoring procurement of materials. This research has been obtained optimal ordering period for the primary items of main building structure with elements of the work using Fixed Period Requirement method. Inventories were already meet the material requirement of each period. Material management has been conducted based grouping approach as many as 31 groups. In addition, this research has proposed the inventory control cards as an instrument for material procurement monitoring. The implications of inventory control cards are coordinate contracting parties with vendors to plan the replenishment of materials to meet the work schedule. Further research can be developed with other aspects such as integrated material order system between contractors and vendors to consider the safety stock. In addition, the information system for planning material is an important consideration for construction projects with large scale so that the companies can plan primary items inventory and other materials in the projects completion more easily, quickly and accurately.
Accounting for special nuclear material contained in fabricated nuclear fuel rod items has been completely automated at the Westinghouse Nuclear Fuel Division facility in Columbia, South Carolina. Experience with the automated system has shown substantial difficulty in maintaining current knowledge of the precise locations of rods pulled out of the ''normal'' processing cycle. This has been resolved by creation of two tightly controlled staging areas for handling and distribution of all ''deviant'' rods by two specially trained expeditors. Thus, coupling automated data collection with centralized expert handling and distribution has created a viable system for control of large numbers of fuel rods in a major fabrication plant
Michalis P Michaelides
Full Text Available Many studies have investigated the topic of change or drift in item parameter estimates in the context of Item Response Theory. Content effects, such as instructional variation and curricular emphasis, as well as context effects, such as the wording, position, or exposure of an item have been found to impact item parameter estimates. The issue becomes more critical when items with estimates exhibiting differential behavior across test administrations are used as common for deriving equating transformations. This paper reviews the types of effects on IRT item parameter estimates and focuses on the impact of misbehaving or aberrant common items on equating transformations. Implications relating to test validity and the judgmental nature of the decision to keep or discard aberrant common items are discussed, with recommendations for future research into more informed and formal ways of dealing with misbehaving common items.
Michaelides, Michalis P
Many studies have investigated the topic of change or drift in item parameter estimates in the context of item response theory (IRT). Content effects, such as instructional variation and curricular emphasis, as well as context effects, such as the wording, position, or exposure of an item have been found to impact item parameter estimates. The issue becomes more critical when items with estimates exhibiting differential behavior across test administrations are used as common for deriving equating transformations. This paper reviews the types of effects on IRT item parameter estimates and focuses on the impact of misbehaving or aberrant common items on equating transformations. Implications relating to test validity and the judgmental nature of the decision to keep or discard aberrant common items are discussed, with recommendations for future research into more informed and formal ways of dealing with misbehaving common items.
Kim, Kyungmi; Yi, Do-Joon; Raye, Carol L; Johnson, Marcia K
In the present study, we explored how item repetition affects source memory for new item-feature associations (picture-location or picture-color). We presented line drawings varying numbers of times in Phase 1. In Phase 2, each drawing was presented once with a critical new feature. In Phase 3, we tested memory for the new source feature of each item from Phase 2. Experiments 1 and 2 demonstrated and replicated the negative effects of item repetition on incidental source memory. Prior item repetition also had a negative effect on source memory when different source dimensions were used in Phases 1 and 2 (Experiment 3) and when participants were explicitly instructed to learn source information in Phase 2 (Experiments 4 and 5). Importantly, when the order between Phases 1 and 2 was reversed, such that item repetition occurred after the encoding of critical item-source combinations, item repetition no longer affected source memory (Experiment 6). Overall, our findings did not support predictions based on item predifferentiation, within-dimension source interference, or general interference from multiple traces of an item. Rather, the findings were consistent with the idea that prior item repetition reduces attention to subsequent presentations of the item, decreasing the likelihood that critical item-source associations will be encoded.
...). This report is the third in a series of reports regarding the consumable item transfer (CIT), phase II. The Deputy Secretary of Defense directed the transfer of the management of consumable items to Defense Logistics Agency...
Bisby, J. A.; Burgess, N.
The formation of associations between items and their context has been proposed to rely on mechanisms distinct from those supporting memory for a single item. Although emotional experiences can profoundly affect memory, our understanding of how it interacts with different aspects of memory remains unclear. We performed three experiments to examine the effects of emotion on memory for items and their associations. By presenting neutral and negative items with background contexts, Experiment 1 ...
... 26 Internal Revenue 18 2010-04-01 2010-04-01 false Partnership items. 301.6501(o)-3 Section 301... § 301.6501(o)-3 Partnership items. (a) Partnership item defined. For purposes of section 6501(o) (as it..., and § 301.6511(g)-1, the term “partnership item” means— (1) Any item required to be taken into account...
A coordinate system free definition of complex structure multidimensional item response theory (MIRT) for dichotomously scored items is presented. The point of view taken emphasizes the possibilities and subtleties of understanding MIRT as a multidimensional extension of the ``classical'' unidimensional item response theory models. The main theorem of the paper is that every monotonic MIRT model looks the same; they are all trivial extensions of univariate item response theory.
Brown, James Dean
The reliability and validity of a cloze procedure used as an English-as-a-second-language (ESL) test in China were improved by applying traditional item analysis and selection techniques. The 'best' test items were chosen on the basis of item facility and discrimination indices, and were administered as a 'tailored cloze.' 29 references listed.…
Davis, Diane, Ed.
This document contains 519 criterion-referenced multiple choice and true or false test items for a course in electronics. The test item bank is designed to work with both the Vocational Instructional Management System (VIMS) and the Vocational Administrative Management System (VAMS) in Missouri. The items are grouped into 15 units covering the…
While the methodology used in developing test items can vary significantly, to ensure quality examinations, test items should be developed systematically. Test design and development is discussed in the DOE Guide to Good Practices for Design, Development, and Implementation of Examinations. This guide is intended to be a supplement by providing more detailed guidance on the development of specific test items. This guide addresses the development of written examination test items primarily. However, many of the concepts also apply to oral examinations, both in the classroom and on the job. This guide is intended to be used as guidance for the classroom and laboratory instructor or curriculum developer responsible for the construction of individual test items. This document focuses on written test items, but includes information relative to open-reference (open book) examination test items, as well. These test items have been categorized as short-answer, multiple-choice, or essay. Each test item format is described, examples are provided, and a procedure for development is included. The appendices provide examples for writing test items, a test item development form, and examples of various test item formats.
Assessing difference between classical test theory and item response theory methods in scoring primary four multiple choice objective test items. ... All research participants were ranked on the CTT number correct scores and the corresponding IRT item pattern scores from their performance on the PRISMADAT. Wilcoxon ...
... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true GSA stock items. 101-27.209-1 Section 101-27.209-1 Public Contracts and Property Management Federal Property Management...-Management of Shelf-Life Materials § 101-27.209-1 GSA stock items. Shelf-life items that meet the criteria...
Kabasakal, Kübra Atalay; Kelecioglu, Hülya
This study examines the effect of differential item functioning (DIF) items on test equating through multilevel item response models (MIRMs) and traditional IRMs. The performances of three different equating models were investigated under 24 different simulation conditions, and the variables whose effects were examined included sample size, test…
Australian Council for Educational Research, Hawthorn.
This publication contains 317 multiple-choice chemistry test items related to topics covered in the Victorian (Australia) Year 12 chemistry course. It allows teachers access to a range of items suitable for diagnostic and achievement purposes, supplementing the ACER Chemistry Test Item Collection--Year 12 (CHEMTIC). The topics covered are: organic…
Eggen, Theodorus Johannes Hendrikus Maria; Eggen, T.J.H.M.; Veldkamp, B.P.
Item selection methods traditionally developed for computerized adaptive testing (CAT) are explored for their usefulness in item-based computerized adaptive learning (CAL) systems. While in CAT Fisher information-based selection is optimal, for recovering learning populations in CAL systems item
... for acceptance. (a) A Reserve Bank or a subsequent collecting bank may, if instructed by the sender, present a noncash item for acceptance in any manner authorized by law if— (1) The item provides that it... 12 Banks and Banking 2 2010-01-01 2010-01-01 false Presenting noncash items for acceptance. 210.8...
Trotman-Dickenson, D. I.
Describes some of the problems in writing data response items in economics for use by A Level and General Certificate of Secondary Education (GCSE) students. Examines the experience of two series of workshops on writing items, evaluating them and assessing responses from schools. Offers suggestions for producing packages of data response items as…
Khalid, Muhammad Naveed; Glas, Cornelis A.W.
Item bias or differential item functioning (DIF) has an important impact on the fairness of psychological and educational testing. In this paper, DIF is seen as a lack of fit to an item response (IRT) model. Inferences about the presence and importance of DIF require a process of so-called test
...) from item response theory (IRT). DIF was found for the majority of the 40 items examined, although in many cases the DIF indicated improvements in the revised items. Implications for these scales and for the use of IRT with the MEOCS are discussed.
Jin, Kuan-Yu; Wang, Wen-Chung
Sometimes, test-takers may not be able to attempt all items to the best of their ability (with full effort) due to personal factors (e.g., low motivation) or testing conditions (e.g., time limit), resulting in poor performances on certain items, especially those located toward the end of a test. Standard item response theory (IRT) models fail to…
Our objective was to evaluate the psychometric properties of a vegetable parenting practices scale using multidimensional polytomous item response modeling which enables assessing item fit to latent variables and the distributional characteristics of the items in comparison to the respondents. We al...
Hung, Man; Voss, Maren W; Bounsanga, Jerry; Crum, Anthony B; Tyser, Andrew R
Clinical measurement. The psychometric properties of the PROMIS v1.2 UE item bank were tested on various samples prior to its release, but have not been fully evaluated among the orthopaedic population. This study assesses the performance of the UE item bank within the UE orthopaedic patient population. The UE item bank was administered to 1197 adult patients presenting to a tertiary orthopaedic clinic specializing in hand and UE conditions and was examined using traditional statistics and Rasch analysis. The UE item bank fits a unidimensional model (outfit MNSQ range from 0.64 to 1.70) and has adequate reliabilities (person = 0.84; item = 0.82) and local independence (item residual correlations range from -0.37 to 0.34). Only one item exhibits gender differential item functioning. Most items target low levels of function. The UE item bank is a useful clinical assessment tool. Additional items covering higher functions are needed to enhance validity. Supplemental testing is recommended for patients at higher levels of function until more high function UE items are developed. 2c. Copyright © 2016 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.
Vaughn, Brandon K.; Wang, Qiu
A nonparametric tree classification procedure is used to detect differential item functioning for items that are dichotomously scored. Classification trees are shown to be an alternative procedure to detect differential item functioning other than the use of traditional Mantel-Haenszel and logistic regression analysis. A nonparametric…
Veerkamp, W.J.J.; Veerkamp, Wim J.J.; Berger, Martijn; Berger, Martijn P.F.
Items with the highest discrimination parameter values in a logistic item response theory (IRT) model do not necessarily give maximum information. This paper shows which discrimination parameter values (as a function of the guessing parameter and the distance between person ability and item
Veerkamp, W.J.J.; Veerkamp, Wim J.J.; Berger, Martijn P.F.; Berger, Martijn
Items with the highest discrimination parameter values in a logistic item response theory model do not necessarily give maximum information. This paper derives discrimination parameter values, as functions of the guessing parameter and distances between person parameters and item difficulty, that
Merino-Soto, Cesar; Salas Blas, Edwin
This research intended to validate two brief scales of sensations seeking with Peruvian adolescents: the eight item scale (BSSS8; Hoyle, Stephenson, Palmgreen, Lorch, y Donohew, 2002) and the four item scale (BSSS4; Stephenson, Hoyle, Slater, y Palmgreen, 2003). Questionnaires were administered to 618 voluntary participants, with an average age of 13.6 years, from different levels of high school, state and private school in a district in the south of Lima. It analyzed the internal structure of both short versions using three models: a) unidimensional (M1), b) oblique or related dimensions (M2), and c) the bifactor model (M3). Results show that both instruments have a single dimension which best represents the variability of the items; a fact that can be explained both by the complexity of the concept and by the small number of items representing each factor, which is more noticeable in the BSSS4. Reliability is within levels found by previous studies: alpha: .745 = BSSS8 and BSSS4 =. 643; omega coefficient: .747 in BSSS8 and .651 in BSSS4. These are considered suitable for the type of instruments studied. Based on the correlation between the two instruments, it was found that there are satisfactory levels of equivalence between the BSSS8 and BSSS4. However, it is recommended that the BSSS4 is mainly used for research and for the purpose of describing populations.
Liu, Chen-Wei; Wang, Wen-Chung
Examinee-selected item (ESI) design, in which examinees are required to respond to a fixed number of items in a given set, always yields incomplete data (i.e., when only the selected items are answered, data are missing for the others) that are likely non-ignorable in likelihood inference. Standard item response theory (IRT) models become infeasible when ESI data are missing not at random (MNAR). To solve this problem, the authors propose a two-dimensional IRT model that posits one unidimensional IRT model for observed data and another for nominal selection patterns. The two latent variables are assumed to follow a bivariate normal distribution. In this study, the mirt freeware package was adopted to estimate parameters. The authors conduct an experiment to demonstrate that ESI data are often non-ignorable and to determine how to apply the new model to the data collected. Two follow-up simulation studies are conducted to assess the parameter recovery of the new model and the consequences for parameter estimation of ignoring MNAR data. The results of the two simulation studies indicate good parameter recovery of the new model and poor parameter recovery when non-ignorable missing data were mistakenly treated as ignorable. © 2017 The British Psychological Society.
Ames, Allison J.; Penfield, Randall D.
Drawing valid inferences from item response theory (IRT) models is contingent upon a good fit of the data to the model. Violations of model-data fit have numerous consequences, limiting the usefulness and applicability of the model. This instructional module provides an overview of methods used for evaluating the fit of IRT models. Upon completing…
Penfield, Randall D.; Myers, Nicholas D.; Wolfe, Edward W.
Measurement invariance in the partial credit model (PCM) can be conceptualized in several different but compatible ways. In this article the authors distinguish between three forms of measurement invariance in the PCM: step invariance, item invariance, and threshold invariance. Approaches for modeling these three forms of invariance are proposed,…
Berger, Moritz; Tutz, Gerhard
Detection of differential item functioning (DIF) by use of the logistic modeling approach has a long tradition. One big advantage of the approach is that it can be used to investigate nonuniform (NUDIF) as well as uniform DIF (UDIF). The classical approach allows one to detect DIF by distinguishing between multiple groups. We propose an…
Jaech, J.L.; Lemaire, R.J.
STR-224 provides generalized procedures to determine required sample sizes, for instance in the course of a Physical Inventory Verification at Bulk Handling Facilities. The present report describes procedures to generate random numbers and select groups of items to be verified in a given stratum through each of the measurement methods involved in the verification. (author). 3 refs
Fedotova, G. A.; Voropai, N. I.; Kovalev, G. F.
This paper is concerned with problems blown up in the development of a new version of the Interstate Standard GOST 27.002 "Industrial product dependability. Terms and definitions". This Standard covers a wide range of technical items and is used in numerous regulations, specifications, standard and technical documentation. A currently available State Standard GOST 27.002-89 was introduced in 1990. Its development involved a participation of scientists and experts from different technical areas, its draft was debated in different audiences and constantly refined, so it was a high quality document. However, after 25 years of its application it's become necessary to develop a new version of the Standard that would reflect the current understanding of industrial dependability, accounting for the changes taking place in Russia in the production, management and development of various technical systems and facilities. The development of a new version of the Standard makes it possible to generalize on a terminological level the knowledge and experience in the area of reliability of technical items, accumulated over a quarter of the century in different industries and reliability research schools, to account for domestic and foreign experience of standardization. Working on the new version of the Standard, we have faced a number of issues and problems on harmonization with the International Standard IEC 60500-192, caused first of all by different approaches to the use of terms and differences in the mentalities of experts from different countries. The paper focuses on the problems related to the chapter "Maintenance, restoration and repair", which caused difficulties for the developers to harmonize term definitions both with experts and the International Standard, which is mainly related to differences between the Russian concept and practice of maintenance and repair and foreign ones.
Full Text Available Abstract Background Previous studies have analyzed the psychometric properties of the World Health Organization Disability Assessment Schedule II (WHO-DAS II using classical omnibus measures of scale quality. These analyses are sample dependent and do not model item responses as a function of the underlying trait level. The main objective of this study was to examine the effectiveness of the WHO-DAS II items and their options in discriminating between changes in the underlying disability level by means of item response analyses. We also explored differential item functioning (DIF in men and women. Methods The participants were 3615 adult general practice patients from 17 regions of Spain, with a first diagnosed major depressive episode. The 12-item WHO-DAS II was administered by the general practitioners during the consultation. We used a non-parametric item response method (Kernel-Smoothing implemented with the TestGraf software to examine the effectiveness of each item (item characteristic curves and their options (option characteristic curves in discriminating between changes in the underliying disability level. We examined composite DIF to know whether women had a higher probability than men of endorsing each item. Results Item response analyses indicated that the twelve items forming the WHO-DAS II perform very well. All items were determined to provide good discrimination across varying standardized levels of the trait. The items also had option characteristic curves that showed good discrimination, given that each increasing option became more likely than the previous as a function of increasing trait level. No gender-related DIF was found on any of the items. Conclusions All WHO-DAS II items were very good at assessing overall disability. Our results supported the appropriateness of the weights assigned to response option categories and showed an absence of gender differences in item functioning.
Eckert, Johanna; Rakoczy, Hannes; Call, Josep
Inductive learning from limited observations is a cognitive capacity of fundamental importance. In humans, it is underwritten by our intuitive statistics, the ability to draw systematic inferences from populations to randomly drawn samples and vice versa. According to recent research in cognitive development, human intuitive statistics develops early in infancy. Recent work in comparative psychology has produced first evidence for analogous cognitive capacities in great apes who flexibly drew inferences from populations to samples. In the present study, we investigated whether great apes (Pongo abelii, Pan troglodytes, Pan paniscus, Gorilla gorilla) also draw inductive inferences in the opposite direction, from samples to populations. In two experiments, apes saw an experimenter randomly drawing one multi-item sample from each of two populations of food items. The populations differed in their proportion of preferred to neutral items (24:6 vs. 6:24) but apes saw only the distribution of food items in the samples that reflected the distribution of the respective populations (e.g., 4:1 vs. 1:4). Based on this observation they were then allowed to choose between the two populations. Results show that apes seemed to make inferences from samples to populations and thus chose the population from which the more favorable (4:1) sample was drawn in Experiment 1. In this experiment, the more attractive sample not only contained proportionally but also absolutely more preferred food items than the less attractive sample. Experiment 2, however, revealed that when absolute and relative frequencies were disentangled, apes performed at chance level. Whether these limitations in apes' performance reflect true limits of cognitive competence or merely performance limitations due to accessory task demands is still an open question. © 2017 Wiley Periodicals, Inc.
Ali, Usama S.; Chang, Hua-Hua; Anderson, Carolyn J.
Polytomous items are typically described by multiple category-related parameters; situations, however, arise in which a single index is needed to describe an item's location along a latent trait continuum. Situations in which a single index would be needed include item selection in computerized adaptive testing or test assembly. Therefore single…
New South Wales Dept. of Education, Sydney (Australia).
As one in a series of test item collections developed by the Assessment and Evaluation Unit of the Directorate of Studies, items are made available to teachers for the construction of unit tests or term examinations or as a basis for class discussion. Each collection was reviewed for content validity and reliability. The test items meet syllabus…
New South Wales Dept. of Education, Sydney (Australia).
As one in a series of test item collections developed by the Assessment and Evaluation Unit of the Directorate of Studies, items are made available to teachers for the construction of unit tests or term examinations or as a basis for class discussion. Each collection was reviewed for content validity and reliability. The test items meet syllabus…
New South Wales Dept. of Education, Sydney (Australia).
As one in a series of test item collections developed by the Assessment and Evaluation Unit of the Directorate of Studies, items are made available to teachers for the construction of unit tests or term examinations or as a basis for class discussion. Each collection was reviewed for content validity and reliability. The test items meet syllabus…
New South Wales Dept. of Education, Sydney (Australia).
New South Wales Dept. of Education, Sydney (Australia).
Full Text Available This paper describes the steps taken to eliminate two of the items in a Test of Figural Analogies (TFA. The main guidelines of psychometric analysis concerning Classical Test Theory (CTT and Item Response Theory (IRT are explained. The item elimination process was based on both the study of the CTT difficulty and discrimination index, and the unidimensionality analysis. The a, b, and c parameters of the Three Parameter Logistic Model of IRT were also considered for this purpose, as well as the assessment of each item fitting this model. The unfavourable characteristics of a group of TFA items are detailed, and decisions leading to their possible elimination are discussed.
Osth, Adam F; Dennis, Simon
A powerful theoretical framework for exploring recognition memory is the global matching framework, in which a cue's memory strength reflects the similarity of the retrieval cues being matched against the contents of memory simultaneously. Contributions at retrieval can be categorized as matches and mismatches to the item and context cues, including the self match (match on item and context), item noise (match on context, mismatch on item), context noise (match on item, mismatch on context), and background noise (mismatch on item and context). We present a model that directly parameterizes the matches and mismatches to the item and context cues, which enables estimation of the magnitude of each interference contribution (item noise, context noise, and background noise). The model was fit within a hierarchical Bayesian framework to 10 recognition memory datasets that use manipulations of strength, list length, list strength, word frequency, study-test delay, and stimulus class in item and associative recognition. Estimates of the model parameters revealed at most a small contribution of item noise that varies by stimulus class, with virtually no item noise for single words and scenes. Despite the unpopularity of background noise in recognition memory models, background noise estimates dominated at retrieval across nearly all stimulus classes with the exception of high frequency words, which exhibited equivalent levels of context noise and background noise. These parameter estimates suggest that the majority of interference in recognition memory stems from experiences acquired before the learning episode. (c) 2015 APA, all rights reserved).
Medhizadah, Shabnam; Classen, Sherrilene; Johnson, Andrew M
The Fitness-to-Drive Screening Measure © (FTDS) enables proxies to identify at-risk older drivers via 54 driving-related items, but may be too lengthy for widespread uptake. We reduced the number of items in the FTDS and validated the shorter measure, using 200 caregiver responses. Exploratory factor analysis and classical test theory techniques were used to determine the most interpretable factor model and the minimum number of items to be used for predicting fitness to drive. The extent to which the shorter FTDS predicted the results of the 54-item FTDS was evaluated through correlational analysis. A three-factor model best represented the empirical data. Classical test theory techniques lead to the development of the 32-item FTDS. The 32-item FTDS was highly correlated ( r = .99, p = .05) with the FTDS. The 32-item FTDS may provide raters with a faster and more efficient way to identify at-risk older drivers.
Stringer, Timothy Kent [Bucyrus, KS; Yerganian, Simon Scott [Lee's Summit, MO
A feeding mechanism and method for feeding minute items, such as capacitors, resistors, or solder preforms. The mechanism is adapted to receive a plurality of the randomly-positioned and randomly-oriented extremely small or minute items, and to isolate, orient, and position one or more of the items in a specific repeatable pickup location wherefrom they may be removed for use by, for example, a computer-controlled automated assembly machine. The mechanism comprises a sliding shelf adapted to receive and support the items; a wiper arm adapted to achieve a single even layer of the items; and a pushing arm adapted to push the items into the pickup location. The mechanism can be adapted for providing the items with a more exact orientation, and can also be adapted for use in a liquid environment.
Bisby, James A; Burgess, Neil
The formation of associations between items and their context has been proposed to rely on mechanisms distinct from those supporting memory for a single item. Although emotional experiences can profoundly affect memory, our understanding of how it interacts with different aspects of memory remains unclear. We performed three experiments to examine the effects of emotion on memory for items and their associations. By presenting neutral and negative items with background contexts, Experiment 1 demonstrated that item memory was facilitated by emotional affect, whereas memory for an associated context was reduced. In Experiment 2, arousal was manipulated independently of the memoranda, by a threat of shock, whereby encoding trials occurred under conditions of threat or safety. Memory for context was equally impaired by the presence of negative affect, whether induced by threat of shock or a negative item, relative to retrieval of the context of a neutral item in safety. In Experiment 3, participants were presented with neutral and negative items as paired associates, including all combinations of neutral and negative items. The results showed both above effects: compared to a neutral item, memory for the associate of a negative item (a second item here, context in Experiments 1 and 2) is impaired, whereas retrieval of the item itself is enhanced. Our findings suggest that negative affect impairs associative memory while recognition of a negative item is enhanced. They support dual-processing models in which negative affect or stress impairs hippocampal-dependent associative memory while the storage of negative sensory/perceptual representations is spared or even strengthened.
Tay, Louis; Huang, Qiming; Vermunt, Jeroen K.
In large-scale testing, the use of multigroup approaches is limited for assessing differential item functioning (DIF) across multiple variables as DIF is examined for each variable separately. In contrast, the item response theory with covariate (IRT-C) procedure can be used to examine DIF across multiple variables (covariates) simultaneously. To…
Benefiting from item preknowledge is a major type of fraudulent behavior during educational assessments. Belov suggested the posterior shift statistic for detection of item preknowledge and showed its performance to be better on average than that of seven other statistics for detection of item preknowledge for a known set of compromised items. Sinharay suggested a statistic based on the likelihood ratio test for detection of item preknowledge; the advantage of the statistic is that its null distribution is known. Results from simulated and real data and adaptive and nonadaptive tests are used to demonstrate that the Type I error rate and power of the statistic based on the likelihood ratio test are very similar to those of the posterior shift statistic. Thus, the statistic based on the likelihood ratio test appears promising in detecting item preknowledge when the set of compromised items is known.
Sison, Jo Ann G; Mather, Mara
In the part-set cuing effect, cuing a subset of previously studied items impairs recall of the remaining noncued items. This experiment reveals that cuing participants with previously-studied emotional pictures (e.g., fear-evoking pictures of people) can impair recall of pictures involving the same emotion but different content (e.g., fear-evoking pictures of animals). This indicates that new events can be organized in memory using emotion as a grouping function to create associations. However, whether new information is organized in memory along emotional or nonemotional lines appears to be a flexible process that depends on people's current focus. Mentioning in the instructions that the pictures were either amusement- or fear-related led to memory impairment for pictures with the same emotion as cued pictures, whereas mentioning that the pictures depicted either animals or people led to memory impairment for pictures with the same type of actor.
Full Text Available Previous research on the impact of text and formatting changes on test-item performance has produced mixed results. This matter is important because it is generally acknowledged that any change to an item requires that it be recalibrated. The present study investigated the effects of seven classes of stylistic changes on item difficulty, discrimination, and response time for a subset of 65 items that make up a standardized test for physician licensure completed by 31,918 examinees in 2012. One of two versions of each item (original or revised was randomly assigned to examinees such that each examinee saw only two experimental items, with each item being administered to approximately 480 examinees. The stylistic changes had little or no effect on item difficulty or discrimination; however, one class of edits -' changing an item from an open lead-in (incomplete statement to a closed lead-in (direct question -' did result in slightly longer response times. Data for nonnative speakers of English were analyzed separately with nearly identical results. These findings have implications for the conventional practice of repretesting (or recalibrating items that have been subjected to minor editorial changes.
Kang, Hyeon-Ah; Su, Ya-Hui; Chang, Hua-Hua
A monotone relationship between a true score (τ) and a latent trait level (θ) has been a key assumption for many psychometric applications. The monotonicity property in dichotomous response models is evident as a result of a transformation via a test characteristic curve. Monotonicity in polytomous models, in contrast, is not immediately obvious because item response functions are determined by a set of response category curves, which are conceivably non-monotonic in θ. The purpose of the present note is to demonstrate strict monotonicity in ordered polytomous item response models. Five models that are widely used in operational assessments are considered for proof: the generalized partial credit model (Muraki, 1992, Applied Psychological Measurement, 16, 159), the nominal model (Bock, 1972, Psychometrika, 37, 29), the partial credit model (Masters, 1982, Psychometrika, 47, 147), the rating scale model (Andrich, 1978, Psychometrika, 43, 561), and the graded response model (Samejima, 1972, A general model for free-response data (Psychometric Monograph no. 18). Psychometric Society, Richmond). The study asserts that the item response functions in these models strictly increase in θ and thus there exists strict monotonicity between τ and θ under certain specified conditions. This conclusion validates the practice of customarily using τ in place of θ in applied settings and provides theoretical grounds for one-to-one transformations between the two scales. © 2018 The British Psychological Society.
Chundi, Parvathi; Rosenkrantz, Daniel J.
We propose a special type of time series, which we call an item-set time series, to facilitate the temporal analysis of software version histories, email logs, stock market data, etc. In an item-set time series, each observed data value is a set of discrete items. We formalize the concept of an item-set time series and present efficient algorithms for segmenting a given item-set time series. Segmentation of a time series partitions the time series into a sequence of segments where each segment is constructed by combining consecutive time points of the time series. Each segment is associated with an item set that is computed from the item sets of the time points in that segment, using a function which we call a measure function. We then define a concept called the segment difference, which measures the difference between the item set of a segment and the item sets of the time points in that segment. The segment difference values are required to construct an optimal segmentation of the time series. We describe novel and efficient algorithms to compute segment difference values for each of the measure functions described in the paper. We outline a dynamic programming based scheme to construct an optimal segmentation of the given item-set time series. We use the item-set time series segmentation techniques to analyze the temporal content of three different data sets—Enron email, stock market data, and a synthetic data set. The experimental results show that an optimal segmentation of item-set time series data captures much more temporal content than a segmentation constructed based on the number of time points in each segment, without examining the item set data at the time points, and can be used to analyze different types of temporal data.
Abell, Jeffrey A.; Spicer, John Patrick; Wincek, Michael Anthony; Wang, Hui; Chakraborty, Debejyo
A system includes host and learning machines in electrical communication with sensors positioned with respect to an item of interest, e.g., a weld, and memory. The host executes instructions from memory to predict a binary quality status of the item. The learning machine receives signals from the sensor(s), identifies candidate features, and extracts features from the candidates that are more predictive of the binary quality status relative to other candidate features. The learning machine maps the extracted features to a dimensional space that includes most of the items from a passing binary class and excludes all or most of the items from a failing binary class. The host also compares the received signals for a subsequent item of interest to the dimensional space to thereby predict, in real time, the binary quality status of the subsequent item of interest.
Baker, Frank B
This graduate-level textbook is a tutorial for item response theory that covers both the basics of item response theory and the use of R for preparing graphical presentation in writings about the theory. Item response theory has become one of the most powerful tools used in test construction, yet one of the barriers to learning and applying it is the considerable amount of sophisticated computational effort required to illustrate even the simplest concepts. This text provides the reader access to the basic concepts of item response theory freed of the tedious underlying calculations. It is intended for those who possess limited knowledge of educational measurement and psychometrics. Rather than presenting the full scope of item response theory, this textbook is concise and practical and presents basic concepts without becoming enmeshed in underlying mathematical and computational complexities. Clearly written text and succinct R code allow anyone familiar with statistical concepts to explore and apply item re...
Murray, Alexandra M; Nobre, Anna C; Clark, Ian A; Cravo, André M; Stokes, Mark G
When a memory is forgotten, is it lost forever? Our study shows that selective attention can restore forgotten items to visual short-term memory (VSTM). In our two experiments, all stimuli presented in a memory array were designed to be equally task relevant during encoding. During the retention interval, however, participants were sometimes given a cue predicting which of the memory items would be probed at the end of the delay. This shift in task relevance improved recall for that item. We found that this type of cuing improved recall for items that otherwise would have been irretrievable, providing critical evidence that attention can restore forgotten information to VSTM. Psychophysical modeling of memory performance has confirmed that restoration of information in VSTM increases the probability that the cued item is available for recall but does not improve the representational quality of the memory. We further suggest that attention can restore discrete items to VSTM.
Brown, K.F.; Rankin, W.N.
Yellow items used in Radiologically Controlled Areas (RCAs) that could contain hazardous metals were identified. X-ray fluorescence analyses indicated that thirty of the fifty-two items do contain hazardous metals. It is important to minimize the hazardous metals put into the wastes. The authors recommend that the specifications for all yellow items stocked in Stores be changed to specify that they contain no hazardous metals
This safety evaluation for packaging (SEP) evaluates and documents the ability to safely ship mostly unique inventories of miscellaneous T Plant canyon waste items (T-P Items) encountered during the canyon deck clean off campaign. In addition, this SEP addresses contaminated items and material that may be shipped in a strong tight package (STP). The shipments meet the criteria for onsite shipments as specified by Fluor Hanford in HNF-PRO-154, Responsibilities and Procedures for all Hazardous Material Shipments
This safety evaluation for packaging (SEP) evaluates and documents the ability to safely ship mostly unique inventories of miscellaneous T Plant canyon waste items (T-P Items) encountered during the canyon deck clean off campaign. In addition, this SEP addresses contaminated items and material that may be shipped in a strong tight package (STP). The shipments meet the criteria for onsite shipments as specified by Fluor Hanford in HNF-PRO-154, Responsibilities and Procedures for all Hazardous Material Shipments.
Yoon Soo Park
Full Text Available In response to views on public's right to know, there is growing attention to item disclosure – release of items, answer keys, and performance data to the public – in medical licensure examinations and their potential impact on the test's ability to measure competence and select qualified candidates. Recent debates on this issue have sparked legislative action internationally, including South Korea, with prior discussions among North American countries dating over three decades. The purpose of this study is to identify and analyze three issues associated with item disclosure in medical licensure examinations – 1 fairness and validity, 2 impact on passing levels, and 3 utility of item disclosure – by synthesizing existing literature in relation to standards in testing. Historically, the controversy over item disclosure has centered on fairness and validity. Proponents of item disclosure stress test takers’ right to know, while opponents argue from a validity perspective. Item disclosure may bias item characteristics, such as difficulty and discrimination, and has consequences on setting passing levels. To date, there has been limited research on the utility of item disclosure for large scale testing. These issues requires ongoing and careful consideration.
Kim, Kyungmi; Yi, Do-Joon; Raye, Carol L.; Johnson, Marcia K.
In the present study, we explored how item repetition affects source memory for new item–feature associations (picture–location or picture–color). We presented line drawings varying numbers of times in Phase 1. In Phase 2, each drawing was presented once with a critical new feature. In Phase 3, we tested memory for the new source feature of each item from Phase 2. Experiments 1 and 2 demonstrated and replicated the negative effects of item repetition on incidental source memory. Prior item re...
Zhang, Kun; Korepin, Vladimir
Quantum partial search algorithm is an approximate search. It aims to find a target block (which has the target items). It runs a little faster than full Grover search. In this paper, we consider quantum partial search algorithm for multiple target items unevenly distributed in a database (target blocks have different number of target items). The algorithm we describe can locate one of the target blocks. Efficiency of the algorithm is measured by number of queries to the oracle. We optimize the algorithm in order to improve efficiency. By perturbation method, we find that the algorithm runs the fastest when target items are evenly distributed in database.
Chong Ho Yu
Full Text Available This paper aims to illustrate how data visualization could be utilized to identify errors prior to modeling, using an example with multi-dimensional item response theory (MIRT. MIRT combines item response theory and factor analysis to identify a psychometric model that investigates two or more latent traits. While it may seem convenient to accomplish two tasks by employing one procedure, users should be cautious of problematic items that affect both factor analysis and IRT. When sample sizes are extremely large, reliability analyses can misidentify even random numbers as meaningful patterns. Data visualization, such as median smoothing, can be used to identify problematic items in preliminary data cleaning.
Ángel Vázquez Alonso
Full Text Available The scarce attention to assessment and evaluation in science education research has been especially harmful for Science-Technology-Society (STS education, due to the dialectic, tentative, value-laden, and controversial nature of most STS topics. To overcome the methodological pitfalls of the STS assessment instruments used in the past, an empirically developed instrument (VOSTS, Views on Science-Technology-Society have been suggested. Some methodological proposals, namely the multiple response models and the computing of a global attitudinal index, were suggested to improve the item implementation. The final step of these methodological proposals requires the categorization of STS statements. This paper describes the process of categorization through a scaling procedure ruled by a panel of experts, acting as judges, according to the body of knowledge from history, epistemology, and sociology of science. The statement categorization allows for the sound foundation of STS items, which is useful in educational assessment and science education research, and may also increase teachers’ self-confidence in the development of the STS curriculum for science classrooms.
Camos, Valérie; Lagner, Prune; Loaiza, Vanessa M
Although verbal recall of item and order information is well-researched in short-term memory paradigms, there is relatively little research concerning item and order recall from working memory. The following study examined whether manipulating the opportunity for attentional refreshing and articulatory rehearsal in a complex span task differently affected the recall of item- and order-specific information of the memoranda. Five experiments varied the opportunity for articulatory rehearsal and attentional refreshing in a complex span task, but the type of recall was manipulated between experiments (item and order, order only, and item only recall). The results showed that impairing attentional refreshing and articulatory rehearsal similarly affected recall regardless of whether the scoring procedure (Experiments 1 and 4) or recall requirements (Experiments 2, 3, and 5) reflected item- or order-specific recall. This implies that both mechanisms sustain the maintenance of item and order information, and suggests that the common cumulative functioning of these two mechanisms to maintain items could be at the root of order maintenance.
Wicherts, J.M.; Johnson, W.
It is important to understand potential sources of group differences in the heritability of intelligence test scores. On the basis of a basic item response model we argue that heritabilities which are based on dichotomous item scores normally do not generalize from one sample to the next. If groups
Onwezen, M.C.; Reinders, M.J.; Verain, M.C.D.; Snoek, H.M.
Based on the multi-item Food Choice Questionnaire (FCQ) originally developed by Steptoe and colleagues (1995), the current study developed a single-item FCQ that provides an acceptable balance between practical needs and psychometric concerns. Studies 1 (N = 1851) and 2 (2a (N = 3290), 2b (N =
... administrative control of sensitive items assigned for general use within an organizational unit as appropriate... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Control of sensitive...-INTRODUCTION 1.51-Personal Property Management Standards and Practices § 109-1.5109 Control of sensitive items...
....1010 (Item 1010) Financial statements. (a) Financial information. Furnish the following financial information: (1) Audited financial statements for the two fiscal years required to be filed with the company's... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false (Item 1010) Financial...
which involve only one attribute per item. This is especially true when we are dealing with constructed-response items, we have to measure much more...Service University of Ilinois Educacional Testing Service Rosedal Road Capign. IL 61801 Princeton. K3 08541 Princeton. N3 08541 Dr. Charles LeiS Dr
... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false (Item 406) Code of ethics. 229... 406) Code of ethics. (a) Disclose whether the registrant has adopted a code of ethics that applies to... code of ethics, explain why it has not done so. (b) For purposes of this Item 406, the term code of...
Veldkamp, Bernard P.; van der Linden, Willem J.; Ariel, A.
This paper presents an approach to item pool design that has the potential to improve on the quality of current item pools in educational and psychological testing andhence to increase both measurement precision and validity. The approach consists of the application of mathematical programming
Koger, Helju, 1943-
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Ratcliff, Roger; Thapar, Anjali; McKoon, Gail
The effects of aging and IQ on performance were examined in 4 memory tasks: item recognition, associative recognition, cued recall, and free recall. For item and associative recognition, accuracy and the response time (RT) distributions for correct and error responses were explained by Ratcliff's (1978) diffusion model at the level of individual…
Madan, Christopher R.; Glaholt, Mackenzie G.; Caplan, Jeremy B.
Word properties like imageability and word frequency improve cued recall of verbal paired-associates. We asked whether these enhancements follow simply from prior effects on item-memory, or also strengthen associations between items. Participants studied word pairs varying in imageability or frequency: pairs were "pure" (high-high, low-low) or…
....14 Money and Finance: Treasury Office of the Secretary of the Treasury TERRORISM RISK INSURANCE PROGRAM Disclosures as Conditions for Federal Payment § 50.14 Separate line item. An insurer is deemed to be in compliance with the requirement of providing disclosure on a “separate line item in the policy...
Kingsbury, G. Gage; Zara, Anthony R.
Several classical approaches and alternative approaches to item selection for computerized adaptive testing (CAT) are reviewed and compared. The study also describes procedures for constrained CAT that may be added to classical item selection approaches to allow them to be used for applied testing. (TJH)
Bisby, James A.; Burgess, Neil
The formation of associations between items and their context has been proposed to rely on mechanisms distinct from those supporting memory for a single item. Although emotional experiences can profoundly affect memory, our understanding of how it interacts with different aspects of memory remains unclear. We performed three experiments to examine…
This paper reviews the literature about item response models for the subject level and aggregated level (group level). Group-level item response models (IRMs) are used in the United States in large-scale assessment programs such as the National Assessment of Educational Progress and the California
Ravid, R.; Boxma, O.J.; Perry, D.
We consider a repair facility consisting of one repairman and two arrival streams of failed items, from bases 1 and 2. The arrival processes are independent Poisson processes, and the repair times are independent and identically exponentially distributed. The item types are exchangeable, and a
Ravid, R.; Boxma, O.J.; Perry, D.
We consider a repair facility consisting of one repairman and two arrival streams of failed items, from bases 1 and 2. The arrival processes are independent Poisson processes, and the repair times are independent and identically exponentially distributed. The item types are exchangeable, and a
Roos, Linda L.; And Others
The importance of item feedback in self-adapted testing was studied by comparing feedback and no feedback conditions for computerized adaptive tests and self-adapted tests taken by 363 college students. Results indicate that item feedback is not necessary to realize score differences between self-adapted and computerized adaptive testing. (SLD)
Yang, Ji Seung; Hansen, Mark; Cai, Li
Traditional estimators of item response theory scale scores ignore uncertainty carried over from the item calibration process, which can lead to incorrect estimates of the standard errors of measurement (SEMs). Here, the authors review a variety of approaches that have been applied to this problem and compare them on the basis of their statistical…
Toland, Michael D.
Item response theory (IRT) is a psychometric technique used in the development, evaluation, improvement, and scoring of multi-item scales. This pedagogical article provides the necessary information needed to understand how to conduct, interpret, and report results from two commonly used ordered polytomous IRT models (Samejima's graded…
Fergadiotis, Gerasimos; Kellough, Stacey; Hula, William D.
Purpose: In this study, we investigated the fit of the Philadelphia Naming Test (PNT; Roach, Schwartz, Martin, Grewal, & Brecher, 1996) to an item-response-theory measurement model, estimated the precision of the resulting scores and item parameters, and provided a theoretical rationale for the interpretation of PNT overall scores by relating…
... 48 Federal Acquisition Regulations System 2 2010-10-01 2010-10-01 false Acquisition of commercial... (CONTINUED) CLAUSES AND FORMS FORMS Prescription of Forms 53.212 Acquisition of commercial items. SF 1449 (Rev. 3/2005), Solicitation/Contract/Order for Commercial Items. SF 1449 is prescribed for use in...
... 48 Federal Acquisition Regulations System 2 2010-10-01 2010-10-01 false Evaluation-Commercial....212-2 Evaluation—Commercial Items. As prescribed in 12.301(c), the Contracting Officer may insert a provision substantially as follows: Evaluation—Commercial Items (JAN 1999) (a) The Government will award a...
... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Contracts for commercial... CONTRACT MANAGEMENT QUALITY ASSURANCE Contract Quality Requirements 46.202-1 Contracts for commercial items. When acquiring commercial items (see part 12), the Government shall rely on contractors' existing...
Hu Panpan; Li Youhai; Ma Huijuan; Xi Chunhua; Chen Xianwen; Wang Kai
Background Episodic memory includes information about item memory and source memory.Many researches support the hypothesis that these two memory systems are implemented by different brain structures.The aim of this study was to investigate the characteristics of item memory and source memory processing in patients with Parkinson's disease (PD),and to further verify the hypothesis of dual-process model of source and item memory.Methods We established a neuropsychological battery to measure the performance of item memory and source memory.Totally 35 PD individuals and 35 matched healthy controls (HC) were administrated with the battery.Item memory task consists of the learning and recognition of high-frequency national Chinese characters; source memory task consists of the learning and recognition of three modes (character,picture,and image) of objects.Results Compared with the controls,the idiopathic PD patients have been impaired source memory (PD vs.HC:0.65±0.06 vs.0.72±0.09,P=0.001),but not impaired in item memory (PD vs.HC:0.65±0.07 vs.0.67±0.08,P=0.240).Conclusions The present experiment provides evidence for dissociation between item and source memory in PD patients,thereby strengthening the claim that the item or source memory rely on different brain structures.PD patients show poor source memory,in which dopamine plays a critical role.
Falk, Carl F.; Cai, Li
We present a logistic function of a monotonic polynomial with a lower asymptote, allowing additional flexibility beyond the three-parameter logistic model. We develop a maximum marginal likelihood-based approach to estimate the item parameters. The new item response model is demonstrated on math assessment data from a state, and a computationally…
Glas, Cornelis A.W.
In this paper it is shown that differential item functioning can be evaluated using the Lagrange multiplier test or C. R. Rao's efficient score test. The test is presented in the framework of a number of item response theory (IRT) models such as the Rasch model, the one-parameter logistic model, the
Kelderman, Henk; Rijkes, Carl P.M.; Rijkes, Carl
A loglinear IRT model is proposed that relates polytomously scored item responses to a multidimensional latent space. The analyst may specify a response function for each response, indicating which latent abilities are necessary to arrive at that response. Each item may have a different number of
. Conclusion: The ... difficulty criteria. Key words: Item difficulty, quality control, statistical process control, variable control charts ..... assumed that 68% of the values fall in the interval ± 1.S; .... The balance of the construction of items of exam has ...
Glas, Cornelis A.W.; Dagohoy, A.V.
A person fit test based on the Lagrange multiplier test is presented for three item response theory models for polytomous items: the generalized partial credit model, the sequential model, and the graded response model. The test can also be used in the framework of multidimensional ability
Fox, J.P.; Mulder, J.; Sinharay, Sandip
Two marginal one-parameter item response theory models are introduced, by integrating out the latent variable or random item parameter. It is shown that both marginal response models are multivariate (probit) models with a compound symmetry covariance structure. Several common hypotheses concerning
Fox, Jean-Paul; Mulder, Joris; Sinharay, Sandip
Two marginal one-parameter item response theory models are introduced, by integrating out the latent variable or random item parameter. It is shown that both marginal response models are multivariate (probit) models with a compound symmetry covariance structure. Several common hypotheses concerning
van der Linden, Willem J.
Several models for optimizing incomplete sample designs with respect to information on the item parameters are presented. The following cases are considered: (1) known ability parameters; (2) unknown ability parameters; (3) item sets with multiple ability scales; and (4) response models with
Adema, Jos J.; van der Linden, Willem J.
Recently, linear programming models for test construction were developed. These models were based on the information function from item response theory. In this paper another approach is followed. Two 0-1 linear programming models for the construction of tests using classical item and test
In today's globalized economy, we cannot live without imported products. Most people do not realize how thin the safety net of regulation and inspection really is. Less than three percent of imported products receive any form of government inspection prior to sale. Avoid flea markets, street vendors and deep discount stores. The sellers of counterfeit wares know where to market their products. They look for individuals who are hungry for a brand name item but do not want to pay a brand name price for it. The internet provides anonymity to the sellers of counterfeit products. Unlike Europe, U.S. law does not hold internet-marketing organizations, responsible for the quality of the products sold on their websites. These organizations will remove an individual vendor when a sufficient number of complaints are lodged, but they will not take responsibility for the counterfeit products you may have purchased. EBay has a number of counterfeit product guides to help you avoid being a victim of the sellers of these products. Ten percent of all medications taken worldwide are counterfeit. If you do buy medications on-line, be sure that the National Association of Boards of Pharmacy Verified Internet Pharmacy Practice Sites (VIPPS) recommends the pharmacy you choose to use. Inspect all medication purchases and report any change in color, shape, imprinting or odor to your pharmacist. If you take generic medications these attributes may change from one manufacturer to another. Your pharmacist should inform you of any changes when you refill your prescription. If they do not, get clarification prior to taking the medication. Please note that the Federal Drug Administration (FDA) does not regulate supplements. The FDA only steps in when a specific supplement proves to cause physical harm or contains a regulated ingredient. Due to counterfeiting, Underwriters Laboratories (UL) changed their label design three times since 1996. The new gold label should be attached to the cord
JOSEPH P. EIMICKE
Full Text Available The aims of this paper are to present findings related to differential item functioning (DIF in the Patient Reported Outcome Measurement Information System (PROMIS depression item bank, and to discuss potential threats to the validity of results from studies of DIF. The 32 depression items studied were modified from several widely used instruments. DIF analyses of gender, age and education were performed using a sample of 735 individuals recruited by a survey polling firm. DIF hypotheses were generated by asking content experts to indicate whether or not they expected DIF to be present, and the direction of the DIF with respect to the studied comparison groups. Primary analyses were conducted using the graded item response model (for polytomous, ordered response category data with likelihood ratio tests of DIF, accompanied by magnitude measures. Sensitivity analyses were performed using other item response models and approaches to DIF detection. Despite some caveats, the items that are recommended for exclusion or for separate calibration were "I felt like crying" and "I had trouble enjoying things that I used to enjoy." The item, "I felt I had no energy," was also flagged as evidencing DIF, and recommended for additional review. On the one hand, false DIF detection (Type 1 error was controlled to the extent possible by ensuring model fit and purification. On the other hand, power for DIF detection might have been compromised by several factors, including sparse data and small sample sizes. Nonetheless, practical and not just statistical significance should be considered. In this case the overall magnitude and impact of DIF was small for the groups studied, although impact was relatively large for some individuals.
Mueller, Anne E; Segal, Daniel L; Gavett, Brandon; Marty, Meghan A; Yochim, Brian; June, Andrea; Coolidge, Frederick L
The Geriatric Anxiety Scale (GAS; Segal et al. (Segal, D. L., June, A., Payne, M., Coolidge, F. L. and Yochim, B. (2010). Journal of Anxiety Disorders, 24, 709-714. doi:10.1016/j.janxdis.2010.05.002) is a self-report measure of anxiety that was designed to address unique issues associated with anxiety assessment in older adults. This study is the first to use item response theory (IRT) to examine the psychometric properties of a measure of anxiety in older adults. A large sample of older adults (n = 581; mean age = 72.32 years, SD = 7.64 years, range = 60 to 96 years; 64% women; 88% European American) completed the GAS. IRT properties were examined. The presence of differential item functioning (DIF) or measurement bias by age and sex was assessed, and a ten-item short form of the GAS (called the GAS-10) was created. All GAS items had discrimination parameters of 1.07 or greater. Items from the somatic subscale tended to have lower discrimination parameters than items on the cognitive or affective subscales. Two items were flagged for DIF, but the impact of the DIF was negligible. Women scored significantly higher than men on the GAS and its subscales. Participants in the young-old group (60 to 79 years old) scored significantly higher on the cognitive subscale than participants in the old-old group (80 years old and older). Results from the IRT analyses indicated that the GAS and GAS-10 have strong psychometric properties among older adults. We conclude by discussing implications and future research directions.
Peters, Judith C.; Goebel, Rainer; Roelfsema, Pieter R.
If we search for an item, a representation of this item in our working memory guides attention to matching items in the visual scene. We can hold multiple items in working memory. Do all these items guide attention in parallel? We asked participants to detect a target object in a stream of objects while they maintained a second item in memory for…
Magis, David; Facon, Bruno
Item purification is an iterative process that is often advocated as improving the identification of items affected by differential item functioning (DIF). With test-score-based DIF detection methods, item purification iteratively removes the items currently flagged as DIF from the test scores to get purified sets of items, unaffected by DIF. The…
Full Text Available The role of response time in completing an item can have very different interpretations. Responding more slowly could be positively related to success as the item is answered more carefully. However, the association may be negative if working faster indicates higher ability. The objective of this study was to clarify the validity of each assumption for reasoning items considering the mode of processing. A total of 230 persons completed a computerized version of Raven’s Advanced Progressive Matrices test. Results revealed that response time overall had a negative effect. However, this effect was moderated by items and persons. For easy items and able persons the effect was strongly negative, for difficult items and less able persons it was less negative or even positive. The number of rules involved in a matrix problem proved to explain item difficulty significantly. Most importantly, a positive interaction effect between the number of rules and item response time indicated that the response time effect became less negative with an increasing number of rules. Moreover, exploratory analyses suggested that the error type influenced the response time effect.
Sheldon, Signy; Levine, Brian
During autobiographical memory retrieval, the medial temporal lobes (MTL) relate together multiple event elements, including object (within-item relations) and context (item-context relations) information, to create a cohesive memory. There is consistent support for a functional specialization within the MTL according to these relational processes, much of which comes from recognition memory experiments. In this study, we compared brain activation patterns associated with retrieving within-item relations (i.e., associating conceptual and sensory-perceptual object features) and item-context relations (i.e., spatial relations among objects) with respect to naturalistic autobiographical retrieval. We developed a novel paradigm that cued participants to retrieve information about past autobiographical events, non-episodic within-item relations, and non-episodic item-context relations with the perceptuomotor aspects of retrieval equated across these conditions. We used multivariate analysis techniques to extract common and distinct patterns of activity among these conditions within the MTL and across the whole brain, both in terms of spatial and temporal patterns of activity. The anterior MTL (perirhinal cortex and anterior hippocampus) was preferentially recruited for generating within-item relations later in retrieval whereas the posterior MTL (posterior parahippocampal cortex and posterior hippocampus) was preferentially recruited for generating item-context relations across the retrieval phase. These findings provide novel evidence for functional specialization within the MTL with respect to naturalistic memory retrieval. © 2015 Wiley Periodicals, Inc.
... petroleum products and electronic items available from the Defense Logistics Agency. 101-26.605 Section 101... available from the Defense Logistics Agency. Agencies required to use GSA supply sources should also use... Logistics Agency, the catalog will contain only those items in Federal supply classification classes which...
Gattamorta, Karina A.; Penfield, Randall D.; Myers, Nicholas D.
Measurement invariance is a common consideration in the evaluation of the validity and fairness of test scores when the tested population contains distinct groups of examinees, such as examinees receiving different forms of a translated test. Measurement invariance in polytomous items has traditionally been evaluated at the item-level,…
Bilir, Mustafa Kuzey
This study uses a new psychometric model (mixture item response theory-MIMIC model) that simultaneously estimates differential item functioning (DIF) across manifest groups and latent classes. Current DIF detection methods investigate DIF from only one side, either across manifest groups (e.g., gender, ethnicity, etc.), or across latent classes…
Full Text Available This study examines the degree of acquiescence present when the item and response formats of a summated rating scale are varied. It is often recommended that acquiescence response bias in rating scales may be controlled by using both positively and negatively worded items. Such items are generally worded in the Likert-type format of statements. The purpose of the study was to establish whether items in question format would result in a smaller degree of acquiescence than items worded as statements. the response format was also varied (five- and seven-point options to determine whether this would influence the reliability and degree of acquiescence in the scales. A twenty-item Locus of Control (LC questionnaire was used, but each item was complemented by its opposite, resulting in 40 items. The subjects, divided randomly into two groups, were second year students who had to complete four versions of the questionnaire, plus a shortened version of Bass's scale for measuring acquiescence. The LC version were questions or statements each combined with a five- or seven-point respons format. Partial counterbalancing was introduced by testing on two separate occasions, presenting the tests to the two groups in the opposite order. The degree of acquiescence was assessed by correlating the items with their opposite, and by correlating scores on each version with scores on the acquiescence questionnaire. No major difference were found between the various item and response format in relation to acquiescence. Opsomming Hierdie ondersoek is uitgevoer om te bepaal of die mate van instemmingsgeneigdheid deur die item- en responsformaat van 'n gesommeerde selfbeoordelingskaal beinvloed word. Daar word dikwels aanbeveel dat die gebruik van positief- sowel as negatiefbewoorde items in 'n vraelys instemmingsgeneigdheid beperk. Suike items word gewoonlik in die tradisionele Likertformaat as stellings geformuleer. Die doel van die ondersoek was om te bepaal of items
Full Text Available The paper discusses the macrostructural treatment of multi-word lexical items in mono- and bilingual dictionaries. First, the classification of multi-word lexical items is presented, and special attention is paid to the discussion of compounds – a specific group of multi-word lexical items that is most commonly afforded headword status but whose inclusion in the headword list may also depend on spelling. Then the inclusion of multi-word lexical items in monolingual dictionaries is dealt with in greater detail, while the results of a short survey on the inclusion of five randomly chosen multi-word lexical items in seven English monolingual dictionaries are presented. The proposals as to how to treat these five multi-word lexical items in bilingual dictionaries are presented in the section about the inclusion of multi-word lexical items in bilingual dictionaries. The conclusion is that it is most important to take the users’ needs into consideration and to make any dictionary as user friendly as possible.
Feinberg, Richard A; Clauser, Amanda L
In graduate medical education, assessment results can effectively guide professional development when both assessment and feedback support a formative model. When individuals cannot directly access the test questions and responses, a way of using assessment results formatively is to provide item keyword feedback. The purpose of the following study was to investigate whether exposure to item keyword feedback aids in learner remediation. Participants included 319 trainees who completed a medical subspecialty in-training examination (ITE) in 2012 as first-year fellows, and then 1 year later in 2013 as second-year fellows. Performance on 2013 ITE items in which keywords were, or were not, exposed as part of the 2012 ITE score feedback was compared across groups based on the amount of time studying (preparation). For the same items common to both 2012 and 2013 ITEs, response patterns were analyzed to investigate changes in answer selection. Test takers who indicated greater amounts of preparation on the 2013 ITE did not perform better on the items in which keywords were exposed compared to those who were not exposed. The response pattern analysis substantiated overall growth in performance from the 2012 ITE. For items with incorrect responses on both attempts, examinees selected the same option 58% of the time. Results from the current study were unsuccessful in supporting the use of item keywords in aiding remediation. Unfortunately, the results did provide evidence of examinees retaining misinformation.
Inamura, Patricia Y.; Uehara, Vanessa B.; Teixeira, Christian A.H.M.; Mastro, Nelida L. del
For most of prepackaged foods a 10 kGy radiation dose is considered the maximum dose needed; however, the commercially available and practically accepted packaging materials must be suitable for such application. This work describes the application of ionizing radiation on several packaged food items, using 5 dehydrated food items, 5 ready-to-eat meals and 5 ready-to-eat food items irradiated in a 60 Co gamma source with a 3 kGy dose. The quality evaluation of the irradiated samples was performed 2 and 8 months after irradiation. Microbiological analysis (bacteria, fungus and yeast load) was performed. The sensory characteristics were established for appearance, aroma, texture and flavor attributes were also established. From these data, the acceptability of all irradiated items was obtained. All ready-to-eat food items assayed like manioc flour, some pâtés and blocks of raw brown sugar and most of ready-to-eat meals like sausages and chicken with legumes were considered acceptable for microbial and sensory characteristics. On the other hand, the dehydrated food items chosen for this study, such as dehydrated bacon potatoes or pea soups were not accepted by the sensory analysis. A careful dose choice and special irradiation conditions must be used in order to achieve sensory acceptability needed for the commercialization of specific irradiated food items. - Highlights: ► We applied gamma radiation on several kinds of packaged food items. ► Microbiological and sensory analyses were performed 2 and 8 months after irradiation. ► All ready-to-eat food items assayed were approved for microbial and sensory characteristics. ► Most ready-to-eat meals like sausages and chicken with legumes were also acceptable. ► Dehydrated bacon potatoes or pea soups were considered not acceptable.
Mesic, Vanes; Muratovic, Hasnija
Large-scale assessments of student achievement in physics are often approached with an intention to discriminate students based on the attained level of their physics competencies. Therefore, for purposes of test design, it is important that items display an acceptable discriminatory behavior. To that end, it is recommended to avoid extraordinary difficult and very easy items. Knowing the factors that influence physics item difficulty makes it possible to model the item difficulty even before the first pilot study is conducted. Thus, by identifying predictors of physics item difficulty, we can improve the test-design process. Furthermore, we get additional qualitative feedback regarding the basic aspects of student cognitive achievement in physics that are directly responsible for the obtained, quantitative test results. In this study, we conducted a secondary analysis of data that came from two large-scale assessments of student physics achievement at the end of compulsory education in Bosnia and Herzegovina. Foremost, we explored the concept of “physics competence” and performed a content analysis of 123 physics items that were included within the above-mentioned assessments. Thereafter, an item database was created. Items were described by variables which reflect some basic cognitive aspects of physics competence. For each of the assessments, Rasch item difficulties were calculated in separate analyses. In order to make the item difficulties from different assessments comparable, a virtual test equating procedure had to be implemented. Finally, a regression model of physics item difficulty was created. It has been shown that 61.2% of item difficulty variance can be explained by factors which reflect the automaticity, complexity, and modality of the knowledge structure that is relevant for generating the most probable correct solution, as well as by the divergence of required thinking and interference effects between intuitive and formal physics knowledge
Full Text Available Large-scale assessments of student achievement in physics are often approached with an intention to discriminate students based on the attained level of their physics competencies. Therefore, for purposes of test design, it is important that items display an acceptable discriminatory behavior. To that end, it is recommended to avoid extraordinary difficult and very easy items. Knowing the factors that influence physics item difficulty makes it possible to model the item difficulty even before the first pilot study is conducted. Thus, by identifying predictors of physics item difficulty, we can improve the test-design process. Furthermore, we get additional qualitative feedback regarding the basic aspects of student cognitive achievement in physics that are directly responsible for the obtained, quantitative test results. In this study, we conducted a secondary analysis of data that came from two large-scale assessments of student physics achievement at the end of compulsory education in Bosnia and Herzegovina. Foremost, we explored the concept of “physics competence” and performed a content analysis of 123 physics items that were included within the above-mentioned assessments. Thereafter, an item database was created. Items were described by variables which reflect some basic cognitive aspects of physics competence. For each of the assessments, Rasch item difficulties were calculated in separate analyses. In order to make the item difficulties from different assessments comparable, a virtual test equating procedure had to be implemented. Finally, a regression model of physics item difficulty was created. It has been shown that 61.2% of item difficulty variance can be explained by factors which reflect the automaticity, complexity, and modality of the knowledge structure that is relevant for generating the most probable correct solution, as well as by the divergence of required thinking and interference effects between intuitive and formal
basket of items, utilized by many e-commerce sites, cannot take advantage of pre-computed user-to-user similarities. Finally, even though the...not discriminate between items that are present in frequent itemsets and items that are not, while still maintaining the computational advantages of...453219 0.02% 7.74 ccard 42629 68793 398619 0.01% 9.35 ecommerce 6667 17491 91222 0.08% 13.68 em 8002 1648 769311 5.83% 96.14 ml 943 1682 100000 6.31
In the mid-1980s, the Nuclear Regulatory Industry (NRC) began inspecting utility practices of procuring and dedicating commercial grade items intended for plant safety-related applications. As a result of the industry efforts to address NRC concerns, nuclear utilities have enhanced existing programs and procedures for dedication of commercial grade items. Though these programs were originally enhanced to meet NRC concerns, utilities have discovered that the dedication of commercial grade items can also reduce overall procurement costs. This paper will discuss the enhancement of utility dedication programs and demonstrates how utilities have utilized them to reduce procurement costs
Procurement of items and services is one of the important elements during the design and construction of Nuclear Power Plants. The purchaser has to establish and implement controls over the procurement process to ensure that the quality criteria, quality level and other quality requirements specified for the particuliar item or service are taken into account. The effect on safety of an error in service or the malfunction of an item is the most important factor to be considered in determining the extent of quality assurance efforts. A typical example of a procurement process will be demonstrated for safety related mechanical components. (orig./RW)
Full Text Available Previous studies have reported conflicting findings on whether item repetition has beneficial or detrimental effects on source memory. To reconcile such contradictions, we investigated whether the degree of pre-exposure of items can be a potential modulating factor. The experimental procedures spanned two consecutive days. On Day 1, participants were exposed to a set of unfamiliar faces. On Day 2, the same faces presented on the previous day were used again in half of the participants, whereas novel faces were used for the other half. Day 2 procedures consisted of three successive phases: item repetition, source association, and source memory test. In the item repetition phase, half of the face stimuli were repeatedly presented while participants were making male/female judgments. During the source association phase, both the repeated and the unrepeated faces appeared in one of the four locations on the screen. Finally, participants were tested on the location in which a given face was presented during the previous phase and reported the confidence of their memory. Source memory accuracy was measured as the percentage of correct non-guess trials. As results, we found a significant interaction between prior exposure and repetition. Repetition impaired source memory when the items had been pre-exposed on Day 1, while it led to greater accuracy in novel ones. These results show that pre-experimental exposure can modulate the effects of repetition on associative binding between an item and its contextual information, suggesting that pre-existing representation and novelty signal interact to form new episodic memory.
Hannula, Deborah E.; Tranel, Daniel; Allen, John S.; Kirchhoff, Brenda A.; Nickel, Allison E.; Cohen, Neal J.
Objective The objective of this study was to examine the dependence of item memory and relational memory on medial temporal lobe (MTL) structures. Patients with amnesia, who either had extensive MTL damage or damage that was relatively restricted to the hippocampus, were tested, as was a matched comparison group. Disproportionate relational memory impairments were predicted for both patient groups, and those with extensive MTL damage were also expected to have impaired item memory. Method Participants studied scenes, and were tested with interleaved two-alternative forced-choice probe trials. Probe trials were either presented immediately after the corresponding study trial (lag 1), five trials later (lag 5), or nine trials later (lag 9) and consisted of the studied scene along with a manipulated version of that scene in which one item was replaced with a different exemplar (item memory test) or was moved to a new location (relational memory test). Participants were to identify the exact match of the studied scene. Results As predicted, patients were disproportionately impaired on the test of relational memory. Item memory performance was marginally poorer among patients with extensive MTL damage, but both groups were impaired relative to matched comparison participants. Impaired performance was evident at all lags, including the shortest possible lag (lag 1). Conclusions The results are consistent with the proposed role of the hippocampus in relational memory binding and representation, even at short delays, and suggest that the hippocampus may also contribute to successful item memory when items are embedded in complex scenes. PMID:25068665
Defense Management Report Decision 926, "Consolidation of Inventory Control Points," included a recommendation to transfer all consumable items managed by the Military Departments to the Defense Logistics Agency (DLA...
A review of the Washington state requirements for the storage of long equipment items removed from tanks indicate that if the contaminated materials on the long equipment items are analyzed and determined to be DW, and not EHW, the containers can be stored on an uncovered, RCRA approved, storage pad. Long equipment items contaminated with reportable levels of EHW, or suspected of being contaminated with EHW, must be protected from the elements by means of a building or other protective covering that otherwise allows adequate inspection of the containers. Storage of the long equipment item containers on an uncovered storage pad is recommended and will reduce construction costs for new storage by an estimated 60 percent when compared to construction costs for enclosed storage
..., REVENUES, EXPENSES, TAXES AND RESERVES FOR TELECOMMUNICATIONS COMPANIES 1 Operating Revenues and Certain... account of an operating nature are apportioned on a basis consistent with the nature of these items. ...
Tartu katoliku kooli 3. klassi poisi Mario Raitari näitemäng "Kristoph Silvester von Tenderi lugu", mis on esimene lugu sarjast "Mario Raitari kroonika". Näidendit etendab Linnupuu Lastepereteatri trupp
We are providing this report for your information and use. The Deputy Secretary of Defense directed the transfer of the management of consumable items to the Defense Logistics Agency (DLA) in July 1990...
... which its securities are listed or traded. (2) All compensation covered. This Item requires clear... different currency, a footnote must be provided to identify that currency and describe the rate and...
Deshpande, Mukund; Karypis, George
... items that will be of interest to a certain user. User-based collaborative filtering is the most successful technology for building recommender systems to date, and is extensively used in many commercial recommender systems...
... items that will be of interest to a certain user. User-based Collaborative filtering is the most successful technology for building recommender systems to date, and is extensively used in many commercial recommender systems...
... Regulations System FEDERAL PROPERTY MANAGEMENT REGULATIONS SUPPLY AND PROCUREMENT 28-STORAGE AND DISTRIBUTION... accountable item of personal property. Each customer activity shall take all appropriate measures necessary to... Government use. ...
U.S. Department of Health & Human Services — This release contains the Basic Stand Alone (BSA) Durable Medical Equipment (DME) Line Items Public Use Files (PUF) with information from Medicare DME claims. The...
Wang, Jing; Bao, Lei
Item response theory is a popular assessment method used in education. It rests on the assumption of a probability framework that relates students' innate ability and their performance on test questions. Item response theory transforms students' raw test scores into a scaled proficiency score, which can be used to compare results obtained with different test questions. The scaled score also addresses the issues of ceiling effects and guessing, which commonly exist in quantitative assessment. We used item response theory to analyze the force concept inventory (FCI). Our results show that item response theory can be useful for analyzing physics concept surveys such as the FCI and produces results about the individual questions and student performance that are beyond the capability of classical statistics. The theory yields detailed measurement parameters regarding the difficulty, discrimination features, and probability of correct guess for each of the FCI questions.
...) The amount of the total bill assessed as a franchise fee and the identity of the franchising authority... fees and costs itemized pursuant to this section. (c) Local franchising authorities may adopt...
different programmers create files and application programs over a long period. .... In theory or essay questions, alternative methods of solving problems are explored and ... Unworthy items are those that do not focus on the central concept or.
Jul 20, 2017 ... Key words: Food items, Hyperopisus bebe occidentalis, Warri River, condition factor. ... Sufficient food intake aids optimal growth in fish, resulting ... It covers a surface area of 255 km2 with ... examination was carried out.
Hateley, R. J.
Presents a pilot study on student thinking in chemistry. Verbal comments of a group of six college students were recorded and analyzed to identify how each student arrives at the correct answer in fixed response items in chemisty. (HM)
Irwin, Debra E; Gross, Heather E; Stucky, Brian D; Thissen, David; DeWitt, Esi Morgan; Lai, Jin Shei; Amtmann, Dagmar; Khastou, Leyla; Varni, James W; DeWalt, Darren A
Pediatric self-report should be considered the standard for measuring patient reported outcomes (PRO) among children. However, circumstances exist when the child is too young, cognitively impaired, or too ill to complete a PRO instrument and a proxy-report is needed. This paper describes the development process including the proxy cognitive interviews and large-field-test survey methods and sample characteristics employed to produce item parameters for the Patient Reported Outcomes Measurement Information System (PROMIS) pediatric proxy-report item banks. The PROMIS pediatric self-report items were converted into proxy-report items before undergoing cognitive interviews. These items covered six domains (physical function, emotional distress, social peer relationships, fatigue, pain interference, and asthma impact). Caregivers (n = 25) of children ages of 5 and 17 years provided qualitative feedback on proxy-report items to assess any major issues with these items. From May 2008 to March 2009, the large-scale survey enrolled children ages 8-17 years to complete the self-report version and caregivers to complete the proxy-report version of the survey (n = 1548 dyads). Caregivers of children ages 5 to 7 years completed the proxy report survey (n = 432). In addition, caregivers completed other proxy instruments, PedsQL™ 4.0 Generic Core Scales Parent Proxy-Report version, PedsQL™ Asthma Module Parent Proxy-Report version, and KIDSCREEN Parent-Proxy-52. Item content was well understood by proxies and did not require item revisions but some proxies clearly noted that determining an answer on behalf of their child was difficult for some items. Dyads and caregivers of children ages 5-17 years old were enrolled in the large-scale testing. The majority were female (85%), married (70%), Caucasian (64%) and had at least a high school education (94%). Approximately 50% had children with a chronic health condition, primarily asthma, which was diagnosed or treated within 6
Irwin Debra E
Full Text Available Abstract Background Pediatric self-report should be considered the standard for measuring patient reported outcomes (PRO among children. However, circumstances exist when the child is too young, cognitively impaired, or too ill to complete a PRO instrument and a proxy-report is needed. This paper describes the development process including the proxy cognitive interviews and large-field-test survey methods and sample characteristics employed to produce item parameters for the Patient Reported Outcomes Measurement Information System (PROMIS pediatric proxy-report item banks. Methods The PROMIS pediatric self-report items were converted into proxy-report items before undergoing cognitive interviews. These items covered six domains (physical function, emotional distress, social peer relationships, fatigue, pain interference, and asthma impact. Caregivers (n = 25 of children ages of 5 and 17 years provided qualitative feedback on proxy-report items to assess any major issues with these items. From May 2008 to March 2009, the large-scale survey enrolled children ages 8-17 years to complete the self-report version and caregivers to complete the proxy-report version of the survey (n = 1548 dyads. Caregivers of children ages 5 to 7 years completed the proxy report survey (n = 432. In addition, caregivers completed other proxy instruments, PedsQL™ 4.0 Generic Core Scales Parent Proxy-Report version, PedsQL™ Asthma Module Parent Proxy-Report version, and KIDSCREEN Parent-Proxy-52. Results Item content was well understood by proxies and did not require item revisions but some proxies clearly noted that determining an answer on behalf of their child was difficult for some items. Dyads and caregivers of children ages 5-17 years old were enrolled in the large-scale testing. The majority were female (85%, married (70%, Caucasian (64% and had at least a high school education (94%. Approximately 50% had children with a chronic health condition, primarily
Stangegaard, Michael; Hansen, Thomas Møller; Hansen, Anders Johannes
Extraction of DNA from trace items for forensic genetic DNA typing using a manual Chelex based extraction protocol requires addition of Chelex solution to sample tubes containing trace items. Automated of addition of Chelex solution may be hampered by high viscosity of the solution and fast...... sedimentation rate of the Chelex beads. Here, we present a simple method that can be used on an Eppendorf epMotion liquid handler resolving these issues...
Hauswald, Anne; Kissler, Johanna
An item-cued directed forgetting paradigm was used to investigate the ability to control episodic memory and selectively encode complex coloured pictures. A series of photographs was presented to 21 participants who were instructed to either remember or forget each picture after it was presented. Memory performance was later tested with a recognition task where all presented items had to be retrieved, regardless of the initial instructions. A directed forgetting effect that is, better recogni...
Liu, Jin-Hu; Zhou, Tao; Zhang, Zi-Ke; Yang, Zimo; Liu, Chuang; Li, Wei-Min
As one of the major challenges, cold-start problem plagues nearly all recommender systems. In particular, new items will be overlooked, impeding the development of new products online. Given limited resources, how to utilize the knowledge of recommender systems and design efficient marketing strategy for new items is extremely important. In this paper, we convert this ticklish issue into a clear mathematical problem based on a bipartite network representation. Under the most widely used algorithm in real e-commerce recommender systems, the so-called item-based collaborative filtering, we show that to simply push new items to active users is not a good strategy. Interestingly, experiments on real recommender systems indicate that to connect new items with some less active users will statistically yield better performance, namely, these new items will have more chance to appear in other users' recommendation lists. Further analysis suggests that the disassortative nature of recommender systems contributes to such observation. In a word, getting in-depth understanding on recommender systems could pave the way for the owners to popularize their cold-start products with low costs.
Kelley, Troy D; Cassenti, Daniel N; Marusich, Laura R; Ghirardelli, Thomas G
The goal of this research was to examine memories created for the number of items during a visual search task. Participants performed a visual search task for a target defined by a single feature (Experiment 1A), by a conjunction of features (Experiment 1B), or by a specific spatial configuration of features (Experiment 1C). On some trials following the search task, subjects were asked to recall the total number of items in the previous display. In all search types, participants underestimated the total number of items, but the severity of the underestimation varied depending on the efficiency of the search. In three follow-up studies (Experiments 2A, 2B, and 2C) using the same visual stimuli, the participants' only task was to estimate the number of items on each screen. Participants still underestimated the numerosity of the items, although the degree of underestimation was smaller than in the search tasks and did not depend on the type of visual stimuli. In Experiment 3, participants were asked to recall the number of items in a display only once. Subjects still displayed a tendency to underestimate, indicating that the underestimation effects seen in Experiments 1A-1C were not attributable to knowledge of the estimation task. The degree of underestimation depends on the efficiency of the search task, with more severe underestimation in efficient search tasks. This suggests that the lower attentional demands of very efficient searches leads to less encoding of numerosity of the distractor set.
Brand, Bethany L; Chasson, Gregory S; Palermo, Cori A; Donato, Frank M; Rhodes, Kyle P; Voorhees, Emily F
Elevated scores on some MMPI-2 (Minnesota Multiphasic Inventory-2) validity scales are common among patients with dissociative identity disorder (DID), which raises questions about the validity of their responses. Such patients show elevated scores on atypical answers (F), F-psychopathology (Fp), atypical answers in the second half of the test (FB), schizophrenia (Sc), and depression (D) scales, with Fp showing the greatest utility in distinguishing them from coached and uncoached DID simulators. In the current study, we investigated the items on the MMPI-2 F, Fp, FB, Sc, and D scales that were most and least commonly endorsed by participants with DID in our 2014 study and compared these responses with those of coached and uncoached DID simulators. The comparisons revealed that patients with DID most frequently endorsed items related to dissociation, trauma, depression, fearfulness, conflict within family, and self-destructiveness. The coached group more successfully imitated item endorsements of the DID group than did the uncoached group. However, both simulating groups, especially the uncoached group, frequently endorsed items that were uncommonly endorsed by the DID group. The uncoached group endorsed items consistent with popular media portrayals of people with DID being violent, delusional, and unlawful. These results suggest that item endorsement patterns can provide useful information to clinicians making determinations about whether an individual is presenting with DID or feigning. © 2016 American Academy of Psychiatry and the Law.
Loss detection requirements, such as five formula kilograms with 99% probability of detection, which apply to the sum of losses from material in both item and bulk form, constitute a special problem for the nuclear material statistician. Requirements of this type are included in the Material Control and Accounting Reform Amendments described in the Advance Notice of Proposed Rule Making (Federal Register, 46(175):45144-46151). Attribute test sampling of items is the method used to detect gross defects in the inventory of items in a given control unit. Attribute sampling plans are designed to detect a loss of a specificed goal quantity of material with a given probability. In contrast to the methods and statistical models used for item loss detection, bulk material loss detection requires all the material entering and leaving a control unit to be measured and the calculation of a loss estimator that will be tested against an appropriate alarm threshold. The alarm threshold is determined from an estimate of the error inherent in the components of the loss estimator. In this paper a simple grahical method of evaluating the combined capabilities of bulk material loss detection methods and item attribute testing procedures will be described. Quantitative results will be given for several cases, indicating how a decrease in the precision of the item loss detection method tends to force an increase in the precision of the bulk loss detection procedure in order to meet the overall detection requirement. 4 figures
Tylka, Tracy L; Wood-Barcalow, Nichole L
Considered a positive body image measure, the 13-item Body Appreciation Scale (BAS; Avalos, Tylka, & Wood-Barcalow, 2005) assesses individuals' acceptance of, favorable opinions toward, and respect for their bodies. While the BAS has accrued psychometric support, we improved it by rewording certain BAS items (to eliminate sex-specific versions and body dissatisfaction-based language) and developing additional items based on positive body image research. In three studies, we examined the reworded, newly developed, and retained items to determine their psychometric properties among college and online community (Amazon Mechanical Turk) samples of 820 women and 767 men. After exploratory factor analysis, we retained 10 items (five original BAS items). Confirmatory factor analysis upheld the BAS-2's unidimensionality and invariance across sex and sample type. Its internal consistency, test-retest reliability, and construct (convergent, incremental, and discriminant) validity were supported. The BAS-2 is a psychometrically sound positive body image measure applicable for research and clinical settings. Copyright © 2014 Elsevier Ltd. All rights reserved.
Cardamone, Caroline N.; Abbott, Jonathan E.; Rayyan, Saif; Seaton, Daniel T.; Pawl, Andrew; Pritchard, David E.
Item response theory is useful in both the development and evaluation of assessments and in computing standardized measures of student performance. In item response theory, individual parameters (difficulty, discrimination) for each item or question are fit by item response models. These parameters provide a means for evaluating a test and offer a better measure of student skill than a raw test score, because each skill calculation considers not only the number of questions answered correctly, but the individual properties of all questions answered. Here, we present the results from an analysis of the Mechanics Baseline Test given at MIT during 2005-2010. Using the item parameters, we identify questions on the Mechanics Baseline Test that are not effective in discriminating between MIT students of different abilities. We show that a limited subset of the highest quality questions on the Mechanics Baseline Test returns accurate measures of student skill. We compare student skills as determined by item response theory to the more traditional measurement of the raw score and show that a comparable measure of learning gain can be computed.
Liu, Jin-Hu; Zhou, Tao; Zhang, Zi-Ke; Yang, Zimo; Liu, Chuang; Li, Wei-Min
As one of the major challenges, cold-start problem plagues nearly all recommender systems. In particular, new items will be overlooked, impeding the development of new products online. Given limited resources, how to utilize the knowledge of recommender systems and design efficient marketing strategy for new items is extremely important. In this paper, we convert this ticklish issue into a clear mathematical problem based on a bipartite network representation. Under the most widely used algorithm in real e-commerce recommender systems, the so-called item-based collaborative filtering, we show that to simply push new items to active users is not a good strategy. Interestingly, experiments on real recommender systems indicate that to connect new items with some less active users will statistically yield better performance, namely, these new items will have more chance to appear in other users' recommendation lists. Further analysis suggests that the disassortative nature of recommender systems contributes to such observation. In a word, getting in-depth understanding on recommender systems could pave the way for the owners to popularize their cold-start products with low costs. PMID:25479013
United States. Bonneville Power Administration. End-Use Research Section; Applied Management & Planning Group (Firm)
This book constitutes a portion of the primary documentation for the 1992 Pacific Northwest Residential Energy Survey, Phase I. The complete 33-volume set of primary documentation provides information needed by energy analysts and interpreters with respect to planning, execution, data collection, and data management of the PNWRES92-I process. Thirty of these volumes are devoted to different ``views`` of the data themselves, with each view having a special purpose or interest as its focus. Analyses and interpretations of these data will be the subjects of forthcoming publications. Conducted during the late summer and fall months of 1992, PNWRES92-I had the over-arching goal of satisfying basic requirements for a variety of information about the stock of residential units in Bonneville`s service region. Surveys with a similar goal were conducted in 1979 and 1983. This volume discerns the information by state. ``Selected crosstabulations`` refers to a set of nine survey items of wide interest (Dwelling Type, Ownership Type, Year-of-Construction, Dwelling Size, Primary Space-Heating Fuel, Primary Water-Heating Fuel, Household Income for 1991, Utility Type, and Space-Heating Fuels: Systems and Equipment) that were crosstabulated among themselves.
van Wilgen, C.P.; Dijkstra, P.U.; Stewart, R.E.; Ranchor, A.V.; Roodenburg, J.L.N.
There is a high prevalence of depression after cancer treatment. In the literature, several authors have raised questions about assessing somatic symptoms to explore depression after cancer treatment. These somatic sequelae are a consequence of cancer treatment and should cause higher depression
Smits, N.; Finkelman, M.D.; Kelderman, H.
In clinical assessment, efficient screeners are needed to ensure low respondent burden. In this article, Stochastic Curtailment (SC), a method for efficient computerized testing for classification into two classes for observable outcomes, was extended to three classes. In a post hoc simulation study
Full Text Available Penelitian ini bertujuan untuk menghasilkan sebuah alat ukur (tes berpikir kritis yang valid dan reliabel untuk digunakan, baik dalam lingkup pendidikan maupun kerja di Indonesia. Tahapan penelitian dilakukan berdasarkan tahap pengembangan tes menurut Hambleton dan Jones (1993. Kisi-kisi dan pembuatan butir didasarkan pada konsep dalam tes Watson-Glaser Critical Thinking Appraisal (WGCTA. Pada WGCTA, berpikir kritis terdiri dari lima dimensi yaitu Inference, Recognition Assumption, Deduction, Interpretation dan Evaluation of arguments. Uji coba tes dilakukan pada 1.453 peserta tes seleksi karyawan di Surabaya, Gresik, Tuban, Bojonegoro, Rembang. Data dikotomi dianalisis dengan menggunakan model IRT dengan dua parameter yaitu daya beda dan tingkat kesulitan butir. Analisis dilakukan dengan menggunakan program statistik Mplus versi 6.11 Sebelum melakukan analisis dengan IRT, dilakukan pengujian asumsi yaitu uji unidimensionalitas, independensi lokal dan Item Characteristic Curve (ICC. Hasil analisis terhadap 68 butir menghasilkan 15 butir dengan daya beda yang cukup baik dan tingkat kesulitan butir yang berkisar antara –4 sampai dengan 2.448. Sedikitnya jumlah butir yang berkualitas baik disebabkan oleh kelemahan dalam menentukan subject matter experts di bidang berpikir kritis dan pemilihan metode skoring. Kata kunci: Pengembangan tes, berpikir kritis, item response theory DEVELOPING CRITICAL THINKING TEST UTILISING ITEM RESPONSE THEORY Abstract The present study was aimed to develop a valid and reliable instrument in assesing critical thinking which can be implemented both in educational and work settings in Indonesia. Following the Hambleton and Jones’s (1993 procedures on test development, the study developed the instrument by employing the concept of critical thinking from Watson-Glaser Critical Thinking Appraisal (WGCTA. The study included five dimensions of critical thinking as adopted from the WGCTA: Inference, Recognition
Watt, Torquil; Grønvold, Mogens; Hegedüs, Laszlo
To evaluate the extent of differential item functioning (DIF) within the thyroid-specific quality of life patient-reported outcome measure, ThyPRO, according to sex, age, education and thyroid diagnosis.......To evaluate the extent of differential item functioning (DIF) within the thyroid-specific quality of life patient-reported outcome measure, ThyPRO, according to sex, age, education and thyroid diagnosis....
Mixed-format tests containing both multiple-choice (MC) items and constructed-response (CR) items are now widely used in many testing programs. Mixed-format tests often are considered to be superior to tests containing only MC items although the use of multiple item formats leads to measurement challenges in the context of equating conducted under…
Kim, Jiyoung; Chi, Youngshin; Huensch, Amanda; Jun, Heesung; Li, Hongli; Roullion, Vanessa
This article discusses a case study on an item writing process that reflects on our practical experience in an item development project. The purpose of the article is to share our lessons from the experience aiming to demystify item writing process. The study investigated three issues that naturally emerged during the project: how item writers use…
Walker, Timothy J; Tullar, Jessica M; Diamond, Pamela M; Kohl, Harold W; Amick, Benjamin C
Purpose To evaluate factorial validity, scale reliability, test-retest reliability, convergent validity, and discriminant validity of the 8-item Work Limitations Questionnaire (WLQ) among employees from a public university system. Methods A secondary analysis using de-identified data from employees who completed an annual Health Assessment between the years 2009-2015 tested research aims. Confirmatory factor analysis (CFA) (n = 10,165) tested the latent structure of the 8-item WLQ. Scale reliability was determined using a CFA-based approach while test-retest reliability was determined using the intraclass correlation coefficient. Convergent/discriminant validity was tested by evaluating relations between the 8-item WLQ with health/performance variables for convergent validity (health-related work performance, number of chronic conditions, and general health) and demographic variables for discriminant validity (gender and institution type). Results A 1-factor model with three correlated residuals demonstrated excellent model fit (CFI = 0.99, TLI = 0.99, RMSEA = 0.03, and SRMR = 0.01). The scale reliability was acceptable (0.69, 95% CI 0.68-0.70) and the test-retest reliability was very good (ICC = 0.78). Low-to-moderate associations were observed between the 8-item WLQ and the health/performance variables while weak associations were observed between the demographic variables. Conclusions The 8-item WLQ demonstrated sufficient reliability and validity among employees from a public university system. Results suggest the 8-item WLQ is a usable alternative for studies when the more comprehensive 25-item WLQ is not available.
Tessmar, Nancy D. [Los Alamos National Laboratory; Salazar, Michael J. [Los Alamos National Laboratory
Counterfeiting of industrial and commercial grade items is an international problem that places worker safety, program objectives, expensive equipment, and security at risk. In order to prevent the introduction of Suspect/Counterfeit Items (S/CI), this information sheet is being made available as a guide to assist in the implementation of S/CI awareness and controls, in conjunction with subcontractor's/supplier's quality assurance programs. When it comes to counterfeit goods, including industrial materials, items, and equipment, no market is immune. Some manufactures have been known to misrepresent their products and intentionally use inferior materials and processes to manufacture substandard items, whose properties can significantly cart from established standards and specifications. These substandard items termed by the Department of Energy (DOE) as S/CI, pose immediate and potential threats to the safety of DOE and contractor workers, the public, and the environment. Failure of certain systems and processes caused by an S/CI could also have national security implications at Los Alamos National Laboratory (LANL). Nuclear Safety Rules (federal Laws), DOE Orders, and other regulations set forth requirements for DOE contractors to implement effective controls to assure that items and services meet specified requirements. This includes techniques to implement and thereby minimizing the potential threat of entry of S/CI to LANL. As a qualified supplier of goods or services to the LANL, your company will be required to establish and maintain effective controls to prevent the introduction of S/CI to LANL. This will require that your company warrant that all items (including their subassemblies, components, and parts) sold to LANL are genuine (i.e. not counterfeit), new, and unused, and conform to the requirements of the LANL purchase orders/contracts unless otherwise approved in writing to the Los Alamos National Security (LANS) contract administrator
Panoz-Brown, Danielle; Corbin, Hannah E; Dalecki, Stefan J; Gentry, Meredith; Brotheridge, Sydney; Sluka, Christina M; Wu, Jie-En; Crystal, Jonathon D
Vivid episodic memories in people have been characterized as the replay of unique events in sequential order [1-3]. Animal models of episodic memory have successfully documented episodic memory of a single event (e.g., [4-8]). However, a fundamental feature of episodic memory in people is that it involves multiple events, and notably, episodic memory impairments in human diseases are not limited to a single event. Critically, it is not known whether animals remember many unique events using episodic memory. Here, we show that rats remember many unique events and the contexts in which the events occurred using episodic memory. We used an olfactory memory assessment in which new (but not old) odors were rewarded using 32 items. Rats were presented with 16 odors in one context and the same odors in a second context. To attain high accuracy, the rats needed to remember item in context because each odor was rewarded as a new item in each context. The demands on item-in-context memory were varied by assessing memory with 2, 3, 5, or 15 unpredictable transitions between contexts, and item-in-context memory survived a 45 min retention interval challenge. When the memory of item in context was put in conflict with non-episodic familiarity cues, rats relied on item in context using episodic memory. Our findings suggest that rats remember multiple unique events and the contexts in which these events occurred using episodic memory and support the view that rats may be used to model fundamental aspects of human cognition. Copyright © 2016 Elsevier Ltd. All rights reserved.
Thamsborg, Lise Laurberg Holst; Petersen, Morten Aa; Aaronson, Neil K
to 12 lack of appetite items. CONCLUSIONS: Phases 1-3 resulted in 12 lack of appetite candidate items. Based on a field testing (phase 4), the psychometric characteristics of the items will be assessed and the final item bank will be generated. This CAT item bank is expected to provide precise...
Peters, Judith C.; Goebel, Rainer; Roelfsema, Pieter R.
If we search for an item, a representation of this item in our working memory guides attention to matching items in the visual scene. We can hold multiple items in working memory. Do all these items guide attention in parallel? We asked participants to detect a target object in a stream of objects
Common test items play an important role in equating multiple test forms under the common-item nonequivalent groups design. Inconsistent item parameter estimates among common items can lead to large bias in equated scores for IRT true score equating. Current methods extensively focus on detection and elimination of outlying common items, which…
He, Yong; Cui, Zhongmin; Fang, Yu; Chen, Hanwei
Common test items play an important role in equating alternate test forms under the common item nonequivalent groups design. When the item response theory (IRT) method is applied in equating, inconsistent item parameter estimates among common items can lead to large bias in equated scores. It is prudent to evaluate inconsistency in parameter…
Chun, Sung-Youn; Jang, Suk-Yong; Choi, Jae-Woo; Shin, Jaeyong; Park, Eun-Cheol
We examined the long-term effects of parental divorce timing on depression using longitudinal data from the Korean Welfare Panel Study. Depression symptoms were measured using the 11 items of Center for Epidemiologic Scale for Depression (CES-D-11), and we categorized parental divorce timing into 'early childhood', 'adolescent' and 'none'. Although participants who experienced parental divorce during adolescence exhibited a significantly higher CES-D-11 score (p = .0468), 'early childhood' participants displayed the most increased CES-D-11 score compared to the control group (p = .0007). Conversely, among participants who were unsatisfied with their marriage, those who experienced parental divorce in early childhood showed lower CES-D-11 scores, while 'adolescent period' participants exhibited significantly higher CES-D-11 scores (p = .0131). We concluded that timing of parental divorce exerts substantial yet varied effects on long-term depression symptoms and future marriage satisfaction. © The Author(s) 2016.
Research purpose: This study assesses the Differential Item Functioning (DIF of the Utrecht Work Engagement Scale (UWES-17 for different South African cultural groups in a South African company. Motivation for the study: Organisations are using the UWES-17 more and more in South Africa to assess work engagement. Therefore, research evidence from psychologists or assessment practitioners on its DIF across different cultural groups is necessary. Research design, approach and method: The researchers conducted a Secondary Data Analysis (SDA on the UWES-17 sample (n = 2429 that they obtained from a cross-sectional survey undertaken in a South African Information and Communication Technology (ICT sector company (n = 24 134. Quantitative item data on the UWES-17 scale enabled the authors to address the research question. Main findings: The researchers found uniform and/or non-uniform DIF on five of the vigour items, four of the dedication items and two of the absorption items. This also showed possible Differential Test Functioning (DTF on the vigour and dedication dimensions. Practical/managerial implications: Based on the DIF, the researchers suggested that organisations should not use the UWES-17 comparatively for different cultural groups or employment decisions in South Africa. Contribution/value add: The study provides evidence on DIF and possible DTF for the UWES-17. However, it also raises questions about possible interaction effects that need further investigation.
Vishkaei, Behzad Maleki; Niaki, S. T. A.; Farhangi, Milad; Rashti, Mehdi Ebrahimnezhad Moghadam
This paper is an extension of Hsu and Hsu (Int J Ind Eng Comput 3(5):939-948, 2012) aiming to determine the optimal order quantity of product batches that contain defective items with percentage nonconforming following a known probability density function. The orders are subject to 100 % screening process at a rate higher than the demand rate. Shortage is backordered, and defective items in each ordering cycle are stored in a warehouse to be returned to the supplier when a new order is received. Although the retailer does not sell defective items at a lower price and only trades perfect items (to avoid loss), a higher holding cost incurs to store defective items. Using the renewal-reward theorem, the optimal order and shortage quantities are determined. Some numerical examples are solved at the end to clarify the applicability of the proposed model and to compare the new policy to an existing one. The results show that the new policy provides better expected profit per time.
Lukmanova Inessa Galeevna
Calculation of reduction of the overall cost of the real estate item that has improved quality indicators in comparison with the overall cost of the real estate item of satisfactory quality, taken as a benchmark, is made. The nature of interrelation between the quality of building works and maintenance expenses is provided. The overall cost of the item increases alongside with the increase of its quality, therefore the pre-set quality indicator should be defined by taking account of the market conditions, rates charged for building works and payable by buyers, and the amount of building works that sell at a higher price. The indicator of the overall cost of the item of real estate, if forthcoming operational expenses are taken into account, i.e. calculated for the course of the overall life cycle of the item, is essential if the investor is going to maintain the building. Investors often act as sellers of completed buildings; therefore, the product price set at the time when it is offered for sale is of particular importance.
Watt, Torquil; Groenvold, Mogens; Hegedüs, Laszlo; Bonnema, Steen Joop; Rasmussen, Åse Krogh; Feldt-Rasmussen, Ulla; Bjorner, Jakob Bue
To evaluate the extent of differential item functioning (DIF) within the thyroid-specific quality of life patient-reported outcome measure, ThyPRO, according to sex, age, education and thyroid diagnosis. A total of 838 patients with benign thyroid diseases completed the ThyPRO questionnaire (84 five-point items, 13 scales). Uniform and nonuniform DIF were investigated using ordinal logistic regression, testing for both statistical significance and magnitude (∆R(2) > 0.02). Scale level was estimated by the sum score, after purification. Twenty instances of DIF in 17 of the 84 items were found. Eight according to diagnosis, where the goiter scale was the one most affected, possibly due to differing perceptions in patients with auto-immune thyroid diseases compared to patients with simple goiter. Eight DIFs according to age were found, of which 5 were in positively worded items, which younger patients were more likely to endorse; one according to gender: women were more likely to report crying, and three according to educational level. The vast majority of DIF had only minor influence on the scale scores (0.1-2.3 points on the 0-100 scales), but two DIF corresponded to a difference of 4.6 and 9.8, respectively. Ordinal logistic regression identified DIF in 17 of 84 items. The potential impact of this on the present scales was low, but items displaying DIF could be avoided when developing abbreviated scales, where the potential impact of DIF (due to fewer items) will be larger.
Full Text Available Humans need to be able to selectively control their memories. Here, we investigate the underlying processes in item-method directed forgetting and compare the classic active memory cues in this paradigm with a passive instruction. Typically, individual items are presented and each is followed by either a forget- or remember-instruction. On a surprise test of all items, memory is then worse for to-be-forgotten items (TBF compared to to-be-remembered items (TBR. This is thought to result from selective rehearsal of TBR, or from active inhibition of TBF, or from both. However, evidence suggests that if a forget instruction initiates active processing, paradoxical effects may also arise. To investigate the underlying mechanisms, four experiments were conducted where un-cued items (UI were introduced and recognition performance was compared between TBR, TBF and UI stimuli. Accuracy was encouraged via a performance-dependent monetary bonus. Across all experiments, including perceptually fully matched variants, memory accuracy for TBF was reduced compared to TBR, but better than for UI. Moreover, participants used a more conservative response criterion when responding to TBF stimuli. Thus, ironically, the F cue results in active processing, but this does not have inhibitory effects that would impair recognition memory beyond a un-cued baseline condition. This casts doubts on inhibitory accounts of item-method directed forgetting and is also difficult to reconcile with pure selective rehearsal of TBR. While the F-cue does induce active processing, this does not result in particularly successful forgetting. The pattern seems most consistent with the notion of ironic processing.
Full Text Available The classic economic production quantity (EPQ model has been widely used to determine the optimal production quantity. However, the analysis for finding an EPQ model has many weaknesses which lead many researchers and practitioners to make extensions in several aspects on the original EPQ model. The basic assumption of EPQ model is that 100% of manufactured products are non-defective that is not valid for many production processes generally. The purpose of this paper is to develop an EPQ model with grey demand rate and cost values with maximum backorder level allowed with the good quality items in units under an imperfect production process. The imperfect items are considered to be low quality items which are sold to a particular purchaser at a lower price and, the others are reworked and scrapped. A mathematical model is developed and then an industrial example is presented on the wooden chipboard production process for illustration of the proposed model.
The principle of integrality, moderation and equilibrium should be considered in the safety classification of items in nuclear power plant. The basic ways for safety classification of items is to classify the safety function based on the effect of the outside enclosure damage of the items (parts) on the safety. Tianwan Nuclear Power Plant adopts Russian VVER-1000/428 type reactor, it safety classification mainly refers to Russian Guidelines and standards. The safety classification of the electric equipment refers to IEEE-308(80) standard, including 1E and Non 1E classification. The safety classification of the instrumentation and control equipment refers to GB/T 15474-1995 standard, including safety 1E, safety-related SR and NC non-safety classification. The safety classification of Tianwan Nuclear Power Plant has to be approved by NNSA and satisfy Chinese Nuclear Safety Guidelines. (authors)
Full Text Available The test of relational reasoning (TORR is designed to assess the ability to identify complex patterns within visuospatial stimuli. The TORR is designed for use in school and university settings, and therefore, its measurement invariance across diverse groups is critical. In this investigation, a large sample, representative of a major university on key demographic variables, was collected, and the resulting data were analyzed using a multi-group, multidimensional item-response theory model-comparison procedure. No significant differential item functioning was found on any of the TORR items across any of the demographic groups of interest. This finding is interpreted as evidence of the cultural fairness of the TORR, and potential test-development choices that may have contributed to that cultural fairness are discussed.
Hauswald, Anne; Kissler, Johanna
An item-cued directed forgetting paradigm was used to investigate the ability to control episodic memory and selectively encode complex coloured pictures. A series of photographs was presented to 21 participants who were instructed to either remember or forget each picture after it was presented. Memory performance was later tested with a recognition task where all presented items had to be retrieved, regardless of the initial instructions. A directed forgetting effect--that is, better recognition of "to-be-remembered" than of "to-be-forgotten" pictures--was observed, although its size was smaller than previously reported for words or line drawings. The magnitude of the directed forgetting effect correlated negatively with participants' depression and dissociation scores. The results indicate that, at least in an item method, directed forgetting occurs for complex pictures as well as words and simple line drawings. Furthermore, people with higher levels of dissociative or depressive symptoms exhibit altered memory encoding patterns.
Ruth A. Childs
Full Text Available Matrix sampling of items -' that is, division of a set of items into different versions of a test form..-' is used by several large-scale testing programs. Like other test designs, matrixed designs have..both advantages and disadvantages. For example, testing time per student is less than if each..student received all the items, but the comparability of student scores may decrease. Also,..curriculum coverage is maintained, but reporting of scores becomes more complex. In this paper,..matrixed designs are compared with more traditional designs in nine categories of costs:..development costs, materials costs, administration costs, educational costs, scoring costs,..reliability costs, comparability costs, validity costs, and reporting costs. In choosing among test..designs, a testing program should examine the costs in light of its mandate(s, the content of the..tests, and the financial resources available, among other considerations.
Eduardo Backhoff Escudero
Full Text Available This paper gives an evaluation of different ways to increase university admission test criterion-related validity, by differentially weighting test items. We compared four methods of weighting multiple-choice items of the Basic Skills and Knowledge Examination (EXHCOBA: (1 punishing incorrect responses by a constant factor, (2 weighting incorrect responses, considering the levels of error, (3 weighting correct responses, considering the item’s difficulty, based on the Classic Measurement Theory, and (4 weighting correct responses, considering the item’s difficulty, based on the Item Response Theory. Results show that none of these methods increased the instrument’s predictive validity, although they did improve its concurrent validity. It was concluded that it is appropriate to score the test by simply adding up correct responses.
... Intent To Repatriate Cultural Items: Stanford University Archaeology Center, Stanford, CA AGENCY... the cultural items may contact the Stanford University Archaeology Center. DATES: Representatives of... to repatriate cultural items in the possession of the Stanford University Archaeology Center that...
Keywords: policy, treatment, insulting lexical items, sensitive lexical items, dictionary, woordeboek van die afrikaanse taal, simplexes, compounds, expressions, general usage criterion, labelling, synonyms, metalanguage, collocations, editorial usage examples, citations, advisors, racist lexical items, neutral lemmas, ...
Carter, Nathan T; Dalal, Dev K; Guan, Li; LoPilato, Alexander C; Withrow, Scott A
Psychologists are increasingly positing theories of behavior that suggest psychological constructs are curvilinearly related to outcomes. However, results from empirical tests for such curvilinear relations have been mixed. We propose that correctly identifying the response process underlying responses to measures is important for the accuracy of these tests. Indeed, past research has indicated that item responses to many self-report measures follow an ideal point response process-wherein respondents agree only to items that reflect their own standing on the measured variable-as opposed to a dominance process, wherein stronger agreement, regardless of item content, is always indicative of higher standing on the construct. We test whether item response theory (IRT) scoring appropriate for the underlying response process to self-report measures results in more accurate tests for curvilinearity. In 2 simulation studies, we show that, regardless of the underlying response process used to generate the data, using the traditional sum-score generally results in high Type 1 error rates or low power for detecting curvilinearity, depending on the distribution of item locations. With few exceptions, appropriate power and Type 1 error rates are achieved when dominance-based and ideal point-based IRT scoring are correctly used to score dominance and ideal point response data, respectively. We conclude that (a) researchers should be theory-guided when hypothesizing and testing for curvilinear relations; (b) correctly identifying whether responses follow an ideal point versus dominance process, particularly when items are not extreme is critical; and (c) IRT model-based scoring is crucial for accurate tests of curvilinearity. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Steca, Patrizia; Monzani, Dario; Greco, Andrea; Chiesi, Francesca; Primi, Caterina
This study is aimed at testing the measurement properties of the Life Orientation Test-Revised (LOT-R) for the assessment of dispositional optimism by employing item response theory (IRT) analyses. The LOT-R was administered to a large sample of 2,862 Italian adults. First, confirmatory factor analyses demonstrated the theoretical conceptualization of the construct measured by the LOT-R as a single bipolar dimension. Subsequently, IRT analyses for polytomous, ordered response category data were applied to investigate the items' properties. The equivalence of the items across gender and age was assessed by analyzing differential item functioning. Discrimination and severity parameters indicated that all items were able to distinguish people with different levels of optimism and adequately covered the spectrum of the latent trait. Additionally, the LOT-R appears to be gender invariant and, with minor exceptions, age invariant. Results provided evidence that the LOT-R is a reliable and valid measure of dispositional optimism. © The Author(s) 2014.
Everett, Jim A C
Recent years have seen a surge in psychological research on the relationship between political ideology (particularly conservatism) and cognition, affect, behaviour, and even biology. Despite this flurry of investigation, however, there is as yet no accepted, validated, and widely used multi-item scale of conservatism that is concise, that is modern in its conceptualisation, and that includes both social and economic conservatism subscales. In this paper the 12-Item Social and Economic Conservatism Scale (SECS) is proposed and validated to help fill this gap. The SECS is suggested to be an important and useful tool for researchers working in political psychology.
Furthermore, one of the advantages of the item-based algorithm is that it has much smaller computational require- 11 0.0 0.1 0.2 0.3 0.4 0.5 0.6 ecommerce ...items, utilized by many e-commerce sites, cannot take advantage of pre-computed user-to-user similarities. Consequently, even though the throughput of...Non-Zeros ecommerce 6667 17491 91222 catalog 50918 39080 435524 ccard 42629 68793 398619 skills 4374 2125 82612 movielens 943 1682 100000 Table 1: The
Mindyarto, B. N.; Nugroho, S. E.; Linuwih, S.
Computer-based testing has created the demand for large numbers of items. This paper discusses the production of cohesive physics testlets using an automatic item generation concepts and procedures. The testlets were composed by restructuring physics problems to reveal deeper understanding of the underlying physical concepts by inserting a qualitative question and its scientific reasoning question. A template-based testlet generator was used to generate the testlet variants. Using this methodology, 1248 testlet variants were effectively generated from 25 testlet templates. Some issues related to the effective application of the generated physics testlets in practical assessments were discussed.
Jim A C Everett
Full Text Available Recent years have seen a surge in psychological research on the relationship between political ideology (particularly conservatism and cognition, affect, behaviour, and even biology. Despite this flurry of investigation, however, there is as yet no accepted, validated, and widely used multi-item scale of conservatism that is concise, that is modern in its conceptualisation, and that includes both social and economic conservatism subscales. In this paper the 12-Item Social and Economic Conservatism Scale (SECS is proposed and validated to help fill this gap. The SECS is suggested to be an important and useful tool for researchers working in political psychology.
Errors that are related to some intrinsic property of the items measured are often encountered in nuclear material accounting. An example is the error in nondestructive assay measurements caused by uncorrected matrix effects. Nuclear material accounting requires for each materials type one measurement method for which bounds on these errors can be determined. If such a method is available, a second method might be used to reduce costs or to improve precision. If the measurement error for the first method is longer-tailed than Gaussian, then precision might be improved by measuring all items by both methods. 8 refs
Finkelstein, M.; Vaupel, J.
We consider items that are incepted into operation having already a random (initial) age and define the corresponding remaining lifetime. We show that these lifetimes are identically distributed when the age distribution is equal to the equilibrium distribution of the renewal theory. Then we...... develop the population studies approach to the problem and generalize the setting in terms of stationary and stable populations of items. We obtain new stochastic comparisons for the corresponding population ages and remaining lifetimes that can be useful in applications. Copyright (c) 2014 John Wiley...
DeWispelare, A.R.; Mackin, P.C.; Johnson, R.L.
The Open Item Tracking System (OITS) was developed in response to the Nuclear Regulatory Commission (NRC) need for a reliable, easy to use automated database system, to track all open (awaiting resolution) items related to regulatory, institutional, and technical uncertainties for the Department of Energy's (DOE's) high-level waste (HLW) disposal program. The OITS system was integrated with the Regulatory Program Database (RPD) Version 1.1, resulting in the RPD/OITS Version 2.0 system. RPD/OITS is a network bases system with client server architecture and a graphical user interface. This paper outlines the system and results of its implementation
... Service is not responsible for the determinations in this notice. History and Description of the Cultural...; Items 7 and 12: eagle bone whistle; Item 15: dance club; Item 16: dance staff; Items 23-25: replica... feather headdress; Item 65: medicine bundle; and Item 69: leather tipi bag and contents. Item 16 (dance...
Ghatala, Elizabeth S.; Levin, Joel R.
Two experiments which tested recall differences among young children indicated: (1) organizational factors, not item processing per se, influenced previously found differences in children's recall of pictures following semantic and physical orienting tasks; and (2) physical orienting tasks may effectively inhibit subjects' processing of words, but…
Liu, Yang; Maydeu-Olivares, Alberto
When an item response theory model fails to fit adequately, the items for which the model provides a good fit and those for which it does not must be determined. To this end, we compare the performance of several fit statistics for item pairs with known asymptotic distributions under maximum likelihood estimation of the item parameters: (a) a mean and variance adjustment to bivariate Pearson's X(2), (b) a bivariate subtable analog to Reiser's (1996) overall goodness-of-fit test, (c) a z statistic for the bivariate residual cross product, and (d) Maydeu-Olivares and Joe's (2006) M2 statistic applied to bivariate subtables. The unadjusted Pearson's X(2) with heuristically determined degrees of freedom is also included in the comparison. For binary and ordinal data, our simulation results suggest that the z statistic has the best Type I error and power behavior among all the statistics under investigation when the observed information matrix is used in its computation. However, if one has to use the cross-product information, the mean and variance adjusted X(2) is recommended. We illustrate the use of pairwise fit statistics in 2 real-data examples and discuss possible extensions of the current research in various directions.
Full Text Available Change detection is a classic paradigm that has been used for decades to argue that working memory can hold no more than a fixed number of items ("item-limit models". Recent findings force us to consider the alternative view that working memory is limited by the precision in stimulus encoding, with mean precision decreasing with increasing set size ("continuous-resource models". Most previous studies that used the change detection paradigm have ignored effects of limited encoding precision by using highly discriminable stimuli and only large changes. We conducted two change detection experiments (orientation and color in which change magnitudes were drawn from a wide range, including small changes. In a rigorous comparison of five models, we found no evidence of an item limit. Instead, human change detection performance was best explained by a continuous-resource model in which encoding precision is variable across items and trials even at a given set size. This model accounts for comparison errors in a principled, probabilistic manner. Our findings sharply challenge the theoretical basis for most neural studies of working memory capacity.
This thesis focusses on the analysis and construction of control policies in multiitem production systems. In such systems, multiple items can be made to stock, but they have to share the finite capacity of a single machine. This machine can only produce one unit at a time and if it is set-up for
Carnahan, Laura; Pankratz, Mary Jo; Alberts, Heike
While many college physical geography instructors already use a wide variety of creative teaching approaches in their classes, others have not yet been exposed to teaching with toys, household items, or food. The goal in this article is to present some ideas for teaching college-level physical geography (weather/climate and geomorphology) for…
... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false (Item 1115) Certain derivatives instruments. 229.1115 Section 229.1115 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION STANDARD INSTRUCTIONS FOR FILING FORMS UNDER SECURITIES ACT OF 1933, SECURITIES EXCHANGE ACT OF...
Jakobsen, M. R.; Fernandez, R.; Czerwinski, M.; Inkpen, K.; Kulyk, Olga Anatoliyivna; Robertson, G.G.
We present WIPDash, a visualization for software development teams designed to increase group awareness of work items and code base activity. WIPDash was iteratively designed by working with two development teams, using interviews, observations, and focus groups, as well as sketches of the
Chon, Kyong Hee; Lee, Won-Chan; Dunbar, Stephen B.
In this study we examined procedures for assessing model-data fit of item response theory (IRT) models for mixed format data. The model fit indices used in this study include PARSCALE's G[superscript 2], Orlando and Thissen's S-X[superscript 2] and S-G[superscript 2], and Stone's chi[superscript 2*] and G[superscript 2*]. To investigate the…
... pain relief products; and turbine drip oils. Today's final rule designates the proposed items (with the... political subdivisions or on the distribution of power and responsibilities among the various government... between the Federal Government and Indian tribes, or * * * the distribution of power and responsibilities...
Rossi, R.; Tarim, S.A.; Hnich, B.; Prestwich, S.
In many industrial environments there is a significant class of problems for which the perishable nature of the inventory cannot be ignored in developing replenishment order plans. Food is the most salient example of a perishable inventory item. In this work, we consider the periodic-review,
Shu, Lianghua; Schwarz, Richard D.
As a global measure of precision, item response theory (IRT) estimated reliability is derived for four coefficients (Cronbach's a, Feldt-Raju, stratified a, and marginal reliability). Models with different underlying assumptions concerning test-part similarity are discussed. A detailed computational example is presented for the targeted…
J.E.M. van Nierop; D. Fok (Dennis); Ph.H.B.F. Franses (Philip Hans)
textabstractSales models are mainly used to analyze markets with a fairly small number of items, obtained after aggregating to the brand level. In practice one may require analyses at a more disaggregate level. For example, brand managers may be interested in a comparison across product
... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true Similar items. 101-26.301-1 Section 101-26.301-1 Public Contracts and Property Management Federal Property Management Regulations System FEDERAL PROPERTY MANAGEMENT REGULATIONS SUPPLY AND PROCUREMENT 26-PROCUREMENT SOURCES AND...
... clauses in subcontracts for commercial items: (i) 52.203-13, Contractor Code of Business Ethics and.... (e) To the maximum extent practicable, when the Contractor acts as a purchasing agent for the Government with respect to a purchase that exceeds the simplified acquisition threshold, the Contractor shall...
Denollet, Johan; Smolderen, Kim G E; van den Broek, Krista C
Dysfunctional parenting styles are associated with poor mental and physical health. The 10-item Remembered Relationship with Parents (RRP(10)) scale retrospectively assesses Alienation (dysfunctional communication and intimacy) and Control (overprotection by parents), with an emphasis...... on deficiencies in empathic parenting. We examined the 2-factor structure of the RRP(10) and its relationship with adult depression....
Sørensen, Helene; Andersen, Annemarie Møller
’ and boys’ answers. Twelve items were chosen for focus group interviews with two groups of students – three girls and three boys. The analysis shows that the students need other competencies than in the paper-and-pencil test and another problem solving strategy. In the Danish context this may be one...
... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false (Item 905) comparative...) comparative information. (a)(1) Describe the voting and other rights of investors in the successor under the successor's governing instruments and under applicable law. Compare such rights to the voting and other...
Park, Jong-Hyuck; Park, Jong-Eun; Kwak, Tack-Hun; Yoo, Keun-Bae; Lee, Sang-Guk; Hong, Sung-Yull
Procurement Engineering Process for commercial grade item dedication plays an increasingly important role in operation management of Korea Nuclear Power Plants. The purpose of the Procurement Engineering Process is the provision and assurance of a high quality and quantity of spare, replacement, retrofit and new parts and equipment while maximizing plant availability, minimizing downtime due to parts unavailability and providing reasonable overall program and inventory cost. In this paper, we will review the overview requirements, responsibilities and the process for demonstrating with reasonable assurance that a procured item for potential nuclear safety related services or other essential plant service is adequate with reasonable assurance for its application. This paper does not cover the details of technical evaluation, selecting critical characteristics, selecting acceptance methods, performing failure modes and effects analysis, performing source surveillance, performing quality surveys, performing special tests and inspections, and the other aspects of effective Procurement Engineering and Commercial Grade Item Dedication. The main contribution of this paper is to provide the provision of an overview of Procurement Engineering Process for commercial grade item
Recommender Systems are software agent developed to tackle the problem of information overload by providing recommendations that assist individual users identify contents of interest by using the opinions of a community of users, similarities between items contents or the user's preferences. The exponential growth of ...
Lalor, John P; Wu, Hao; Yu, Hong
Evaluation of NLP methods requires testing against a previously vetted gold-standard test set and reporting standard metrics (accuracy/precision/recall/F1). The current assumption is that all items in a given test set are equal with regards to difficulty and discriminating power. We propose Item Response Theory (IRT) from psychometrics as an alternative means for gold-standard test-set generation and NLP system evaluation. IRT is able to describe characteristics of individual items - their difficulty and discriminating power - and can account for these characteristics in its estimation of human intelligence or ability for an NLP task. In this paper, we demonstrate IRT by generating a gold-standard test set for Recognizing Textual Entailment. By collecting a large number of human responses and fitting our IRT model, we show that our IRT model compares NLP systems with the performance in a human population and is able to provide more insight into system performance than standard evaluation metrics. We show that a high accuracy score does not always imply a high IRT score, which depends on the item characteristics and the response pattern.
Ayotte, Brian J; Trivedi, Ranak; Bosworth, Hayden B
Health-related knowledge is an important component in the self-management of chronic illnesses. The objective of this study was to more accurately assess racial differences in hypertension knowledge by using a latent variable modeling approach that controlled for sociodemographic factors and accounted for measurement issues in the assessment of hypertension knowledge. Cross-sectional data from 1,177 participants (45% African American; 35% female) were analyzed using a multiple indicator multiple causes (MIMIC) modeling approach. Available sociodemographic data included race, education, sex, financial status, and age. All participants completed six items on a hypertension knowledge questionnaire. Overall, the final model suggested that females, Whites, and patients with at least a high school diploma had higher latent knowledge scores than males, African Americans, and patients with less than a high school diploma, respectively. The model also detected differential item functioning (DIF) based on race for two of the items. Specifically, the error rate for African Americans was lower than would be expected given the lower level of latent knowledge on the items, on the questions related to: (a) the association between high blood pressure and kidney disease, and (b) the increased risk African Americans have for developing hypertension. Not accounting for DIF resulted in the difference between Whites and African Americans to be underestimated. These results are discussed in the context of the need for careful measurement of health-related constructs, and how measurement-related issues can result in an inaccurate estimation of racial differences in hypertension knowledge.
... extruding). Examples of items excluded include teriyaki flavored pork loin, roasted peanuts, breaded chicken... OF BEEF, PORK, LAMB, CHICKEN, GOAT MEAT, PERISHABLE AGRICULTURAL COMMODITIES, MACADAMIA NUTS, PECANS... includes cooking (e.g., frying, broiling, grilling, boiling, steaming, baking, roasting), curing (e.g...
Ip, Edward Hak-Sing; Chen, Shyh-Huei
The problem of fitting unidimensional item-response models to potentially multidimensional data has been extensively studied. The focus of this article is on response data that contains a major dimension of interest but that may also contain minor nuisance dimensions. Because fitting a unidimensional model to multidimensional data results in…
Method: A cross-sectional tuck shop survey. Nutritional analyses were conducted using the ... Results: Savoury pies were the most popular lunch item for all learners for both breaks (n = 5, 45%, and n = 3, 27.3%), selling the most number of units (43) per day at eight schools (72.7%). Iced popsicles were sold at almost every ...
... information required by this Item: (1) In a form understandable to investors; and (2) Based upon the facts and... subject to priorities or curtailments which may affect quantities delivered to certain classes of... factors beyond the registrant's control that may affect the registrant's ability to meet its contractual...
Draaijer, S.; Hartog, R.J.M.
A set of design patterns for digital item types has been developed in response to challenges identified in various projects by teachers in higher education. The goal of the projects in question was to design and develop formative and summative tests, and to develop interactive learning material in
Prior to each payment to contractors and suppliers, measurements are made to document the actual amount of pay items placed at the site. This manual process has substantial risk for personnel, and could be made more efficient and less prone to human ...
... segment(s), as reported in the financial statements, that use the properties described. If any such... by the registrant. Detailed descriptions of the physical characteristics of individual properties or... qualitative factors. See Instruction 1 to Item 101 of Regulation S-K (§ 229.101). 3. In the case of an...
Goddard, Chase; Davis, Jeremy; Pyper, Brian
We are interested to see if Item Response Theory can help to better inform the development of reasoning ability in introductory physics. A first pass through our latest batch of data from the Heat and Temperature Conceptual Evaluation, the Lawson Classroom Test of Scientific Reasoning, and the Epistemological Beliefs About Physics Survey may help in this effort.
David Thissen, a professor in the Department of Psychology and Neuroscience, Quantitative Program at the University of North Carolina, has consulted and served on technical advisory committees for assessment programs that use item response theory (IRT) over the past couple decades. He has come to the conclusion that there are usually two purposes…
Ames, Allison J.; Samonte, Kelli
Interest in using Bayesian methods for estimating item response theory models has grown at a remarkable rate in recent years. This attentiveness to Bayesian estimation has also inspired a growth in available software such as WinBUGS, R packages, BMIRT, MPLUS, and SAS PROC MCMC. This article intends to provide an accessible overview of Bayesian…
Huang, Hung-Yu; Wang, Wen-Chung
In the social sciences, latent traits often have a hierarchical structure, and data can be sampled from multiple levels. Both hierarchical latent traits and multilevel data can occur simultaneously. In this study, we developed a general class of item response theory models to accommodate both hierarchical latent traits and multilevel data. The…
Warne, Russell T.; McKyer, E. J. Lisako; Smith, Matthew L.
Objective: To introduce item response theory (IRT) to health behavior researchers by contrasting it with classical test theory and providing an example of IRT in health behavior. Method: Demonstrate IRT by fitting the 2PL model to substance-use survey data from the Adolescent Health Risk Behavior questionnaire (n = 1343 adolescents). Results: An…
The article provides an overview of goodness-of-fit assessment methods for item response theory (IRT) models. It is now possible to obtain accurate "p"-values of the overall fit of the model if bivariate information statistics are used. Several alternative approaches are described. As the validity of inferences drawn on the fitted model…
Andersson, Björn; Xin, Tao
In applications of item response theory (IRT), an estimate of the reliability of the ability estimates or sum scores is often reported. However, analytical expressions for the standard errors of the estimators of the reliability coefficients are not available in the literature and therefore the variability associated with the estimated reliability…
Pritikin, Joshua N.; Hunter, Micheal D.; Boker, Steven M.
This article introduces an item factor analysis (IFA) module for "OpenMx," a free, open-source, and modular statistical modeling package that runs within the R programming environment on GNU/Linux, Mac OS X, and Microsoft Windows. The IFA module offers a novel model specification language that is well suited to programmatic generation…
... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false (Item 1011) Additional information. 229.1011 Section 229.1011 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION STANDARD INSTRUCTIONS FOR FILING FORMS UNDER SECURITIES ACT OF 1933, SECURITIES EXCHANGE ACT OF 1934 AND ENERGY POLICY AND CONSERVATION ACT OF 1975...
... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false (Item 1000) Definitions. 229.1000 Section 229.1000 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION STANDARD INSTRUCTIONS FOR FILING FORMS UNDER SECURITIES ACT OF 1933, SECURITIES EXCHANGE ACT OF 1934 AND ENERGY POLICY AND CONSERVATION ACT OF 1975-REGULATION...
... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false (Item 1016) Exhibits. 229.1016 Section 229.1016 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION STANDARD INSTRUCTIONS FOR FILING FORMS UNDER SECURITIES ACT OF 1933, SECURITIES EXCHANGE ACT OF 1934 AND ENERGY POLICY AND CONSERVATION ACT OF 1975-REGULATION S-...
... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Warranties of commercial... CONTRACT MANAGEMENT QUALITY ASSURANCE Warranties 46.709 Warranties of commercial items. The contracting officer should take advantage of commercial warranties, including extended warranties, where appropriate...
Smith, Clifton L.; And Others
This document contains duties and tasks, multiple-choice test items, and other assessment techniques for Missouri's advanced marketing core curriculum. The core curriculum begins with a list of 13 suggested textbook resources. Next, nine duties with their associated tasks are given. Under each task appears one or more citations to appropriate…
Glas, Cornelis A.W.
Abstract: In the present paper it is shown that differential item functioning can be evaluated using the Lagrange multiplier test or Rao’s efficient score test. The test is presented in the framework of a number of IRT models such as the Rasch model, the OPLM, the 2-parameter logistic model, the
Beisenov Arman Z.
Full Text Available The article considers the findings of items in ancient burials which were intentionally spoiled prior to deposition in graves. This tradition was widely spread both in terms of chronology and geography, and therefore cannot be attributed to any individual cultures or regions. The authors present new information on the ritual obtained during an investigation of Borsyk burial mound of the Middle Sarmatian period located in West Kazakhstan. The central grave of barrow 6 contained a heavily damaged bronze cauldron. The grave was looted in antiquity. Individual scattered bones of a human skeleton and minor gold foil adornments from the ceremonial dress of a nobleman were discovered in the grave. The authors suggest that the cauldron was intentionally deformed by the participants of an ancient mortuary and memorial ritual. According to the principal hypothesis concerning the essence of this ritual, spoilage of the items was related to the idea of assign the items with “different” and “transcendent” properties, which resulted from the necessity of burying the owner. Cauldrons played an important role in the life of steppe leaders. The authors assume a sacral nature of the use of cauldrons in the culture of steppe peoples associated with feasts, battles, and sacred hunting. Perhaps, there was a tradition of burying cauldrons together with their owners after spoiling the items in view of the concept of the other world and the role of a heroic leader therein.
Kazman, Josh B; Scott, Jonathan M; Deuster, Patricia A
The limitations for self-reporting of dietary patterns are widely recognised as a major vulnerability of FFQ and the dietary screeners/scales derived from FFQ. Such instruments can yield inconsistent results to produce questionable interpretations. The present article discusses the value of psychometric approaches and standards in addressing these drawbacks for instruments used to estimate dietary habits and nutrient intake. We argue that a FFQ or screener that treats diet as a 'latent construct' can be optimised for both internal consistency and the value of the research results. Latent constructs, a foundation for item response theory (IRT)-based scales (e.g. Patient Reported Outcomes Measurement Information System) are typically introduced in the design stage of an instrument to elicit critical factors that cannot be observed or measured directly. We propose an iterative approach that uses such modelling to refine FFQ and similar instruments. To that end, we illustrate the benefits of psychometric modelling by using items and data from a sample of 12 370 Soldiers who completed the 2012 US Army Global Assessment Tool (GAT). We used factor analysis to build the scale incorporating five out of eleven survey items. An IRT-driven assessment of response category properties indicates likely problems in the ordering or wording of several response categories. Group comparisons, examined with differential item functioning (DIF), provided evidence of scale validity across each Army sub-population (sex, service component and officer status). Such an approach holds promise for future FFQ.
Luecht, Richard M.
This paper presents a multistage adaptive testing test development paradigm that promises to handle content balancing and other test development needs, psychometric reliability concerns, and item exposure. The bundled multistage adaptive testing (BMAT) framework is a modification of the computer-adaptive sequential testing framework introduced by…
...) Conflicts of interest. (a) Briefly describe the general partner's fiduciary duties to each partnership subject to the roll-up transaction and each actual or potential material conflict of interest between the... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false (Item 909) Conflicts of...
Kujačić Momčilo D.
Full Text Available Delivery of postal items is the last phase in the postal conveyance process. This phase involved up to 57% in total costs of postal items conveyance. In order to reduce the costs of delivery phase, postal organizations apply different methods and techniques. Legal and technological regulations, various restrictions regarding the selection and deployment of employees influence the choice of appropriate methods. Also, the principle of availability of the universal postal service is an essential factor in defining the optimal model. In this paper, the model for assessing and planning of the number of employees in the delivery service observed postal operator has been proposed, with respect to the principles of productivity and accessibility constraints of the universal postal service. This paper will analyze the impact of daily fluctuations in the number of full-time employees and the possibility of hiring a part-time workers in the days with increased traffic volume in the delivery of items, when usually the items from large customers are delivered.
... general. Except as otherwise provided in paragraph (c) of this section, a taxpayer using an accrual method... method of accounting for one or more types of recurring items incurred by the taxpayer. In the case of... basis in the future. (4) Materiality requirement. For purposes of this paragraph (b): (i) In determining...
Full Text Available Online novel recommendation recommends attractive novels according to the preferences and characteristics of users or novels and is increasingly touted as an indispensable service of many online stores and websites. The interests of the majority of users remain stable over a certain period. However, there are broad categories in the initial recommendation list achieved by collaborative filtering (CF. That is to say, it is very possible that there are many inappropriately recommended novels. Meanwhile, most algorithms assume that users can provide an explicit preference. However, this assumption does not always hold, especially in online novel reading. To solve these issues, a tag-driven algorithm with collaborative item modeling (TDCIM is proposed for online novel recommendation. Online novel reading is different from traditional book marketing and lacks preference rating. In addition, collaborative filtering frequently suffers from the Matthew effect, leading to ignored personalized recommendations and serious long tail problems. Therefore, item-based CF is improved by latent preference rating with a punishment mechanism based on novel popularity. Consequently, a tag-driven algorithm is constructed by means of collaborative item modeling and tag extension. Experimental results show that online novel recommendation is improved greatly by a tag-driven algorithm with collaborative item modeling.
Spanjers, L.; van Ommeren, Jan C.W.; Zijm, Willem H.M.
In this paper we consider closed loop two-echelon repairable item systems with repair facilities both at a number of local service centers (called bases) and at a central location (the depot). The goal of the system is to maintain a number of production facilities (one at each base) in optimal
Spanjers, L.; Zijm, Willem H.M.; van Ommeren, Jan C.W.
In this paper we consider closed loop two-echelon repairable item systems with repair facilities both at a number of local service centers (called bases) and at a central location (the depot). The goal of the system is to maintain a number of production facilities (one at each base) in optimal
Spanjers, L.; van Ommeren, Jan C.W.; Zijm, Willem H.M.; Liberopoulos, G.; Papadopoulos, C.T.; Tan, B.; MacGregor Smith, J.; Gershwin, S.B.
In this paper we consider closed loop two-echelon epairable item systems with repair facilities both at a number of local service centers (called bases) and at a central location (the depot). The goal of the system is to maintain a number of production facilities (one at each base) in optimal
... effect on investors, including, but not limited to: (i) Changes in the business plan, voting rights, cash... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false (Item 903) Summary. 229.903 Section 229.903 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION STANDARD...
Section 70.58, ''Fundamental Nuclear Material Controls,'' of 10 CFR Part 70, ''Special Nuclear Material,'' requires certain licensees authorized to possess more than one effective kilogram of special nuclear material to establish Material Balance Areas (MBAs) or Item Control Areas (ICAs) for the physical and administrative control of nuclear materials. This section requires that: (1) each MBA be an identifiable physical area such that the quantity of nuclear material being moved into or out of the MBA is represented by a measured value; (2) the number of MBAs be sufficient to localize nuclear material losses or thefts and identify the mechanisms; (3) the custody of all nuclear material within an MBA or ICA be the responsibility of a single designated individual; and (4) ICAs be established according to the same criteria as MBAs except that control into and out of such areas would be by item identity and count for previously determined special nuclear material quantities, the validity of which must be ensured by tamper-safing unless the items are sealed sources. This guide describes bases acceptable to the NRC staff for the selection of material balance areas and item control areas. (U.S.)
Bowman, Nicholas A.; Herzog, Serge; Sharkness, Jessica
Item Response Theory (IRT) is a measurement theory that is ideal for scale and test development in institutional research, but it is not without its drawbacks. This chapter provides an overview of IRT, describes an example of its use, and highlights the pros and cons of using IRT in applied settings.
Paz, Sylvia H; Spritzer, Karen L; Reise, Steven P; Hays, Ron D
About 70% of Latinos, 5 years old or older, in the United States speak Spanish at home. Measurement equivalence of the PROMIS ® pain interference (PI) item bank by language of administration (English versus Spanish) has not been evaluated. A sample of 527 adult Spanish-speaking Latinos completed the Spanish version of the 41-item PROMIS ® pain interference item bank. We evaluate dimensionality, monotonicity and local independence of the Spanish-language items. Then we evaluate differential item functioning (DIF) using ordinal logistic regression with item response theory scores estimated from DIF-free "anchor" items. One of the 41 items in the Spanish version of the PROMIS ® PI item bank was identified as having significant uniform DIF. English- and Spanish-speaking subjects with the same level of pain interference responded differently to 1 of the 41 items in the PROMIS ® PI item bank. This item was not retained due to proprietary issues. The original English language item parameters can be used when estimating PROMIS ® PI scores.
Gierl, Mark J; Lai, Hollis
Computerised assessment raises formidable challenges because it requires large numbers of test items. Automatic item generation (AIG) can help address this test development problem because it yields large numbers of new items both quickly and efficiently. To date, however, the quality of the items produced using a generative approach has not been evaluated. The purpose of this study was to determine whether automatic processes yield items that meet standards of quality that are appropriate for medical testing. Quality was evaluated firstly by subjecting items created using both AIG and traditional processes to rating by a four-member expert medical panel using indicators of multiple-choice item quality, and secondly by asking the panellists to identify which items were developed using AIG in a blind review. Fifteen items from the domain of therapeutics were created in three different experimental test development conditions. The first 15 items were created by content specialists using traditional test development methods (Group 1 Traditional). The second 15 items were created by the same content specialists using AIG methods (Group 1 AIG). The third 15 items were created by a new group of content specialists using traditional methods (Group 2 Traditional). These 45 items were then evaluated for quality by a four-member panel of medical experts and were subsequently categorised as either Traditional or AIG items. Three outcomes were reported: (i) the items produced using traditional and AIG processes were comparable on seven of eight indicators of multiple-choice item quality; (ii) AIG items can be differentiated from Traditional items by the quality of their distractors, and (iii) the overall predictive accuracy of the four expert medical panellists was 42%. Items generated by AIG methods are, for the most part, equivalent to traditionally developed items from the perspective of expert medical reviewers. While the AIG method produced comparatively fewer plausible
Solano-Flores, Guillermo; Wang, Chao; Shade, Chelsey
We examined multimodality (the representation of information in multiple semiotic modes) in the context of international test comparisons. Using Program of International Student Assessment (PISA)-2009 data, we examined the correlation of the difficulty of science items and the complexity of their illustrations. We observed statistically…
A security scanning system (1) comprises a first stage module (3) having at least one X-ray source (6) and at least three first detectors (7) that are line-shaped and arranged in mutually different orientations and have at least dual energy resolution. A group of carry-on items (4) on a carrier...
Sass, D. A.; Schmitt, T. A.; Walker, C. M.
Item response theory (IRT) procedures have been used extensively to study normal latent trait distributions and have been shown to perform well; however, less is known concerning the performance of IRT with non-normal latent trait distributions. This study investigated the degree of latent trait estimation error under normal and non-normal…
Gorlick, Marissa A; Worthy, Darrell A; Knopik, Valerie S; McGeary, John E; Beevers, Christopher G; Maddox, W Todd
Humans with seven or more repeats in exon III of the DRD4 gene (long DRD4 carriers) sometimes demonstrate impaired attention, as seen in attention-deficit hyperactivity disorder, and at other times demonstrate heightened attention, as seen in addictive behavior. Although the clinical effects of DRD4 are the focus of much work, this gene may not necessarily serve as a "risk" gene for attentional deficits, but as a plasticity gene where attention is heightened for priority items in the environment and impaired for minor items. Here we examine the role of DRD4 in two tasks that benefit from selective attention to high-priority information. We examine a category learning task where performance is supported by focusing on features and updating verbal rules. Here, selective attention to the most salient features is associated with good performance. In addition, we examine the Operation Span (OSPAN) task, a working memory capacity task that relies on selective attention to update and maintain items in memory while also performing a secondary task. Long DRD4 carriers show superior performance relative to short DRD4 homozygotes (six or less tandem repeats) in both the category learning and OSPAN tasks. These results suggest that DRD4 may serve as a "plasticity" gene where individuals with the long allele show heightened selective attention to high-priority items in the environment, which can be beneficial in the appropriate context.
de Vries, Reinout Everhard; Realo, Anu; Allik, Jüri
The use of reliability estimates is increasingly scrutinized as scholars become more aware that test–retest stability and self–other agreement provide a better approximation of the theoretical and practical usefulness of an instrument than its internal reliability. In this study, we investigate item
Meyers, Charles E.; Davidson, George S.; Johnson, David K.; Hendrickson, Bruce A.; Wylie, Brian N.
A method of data mining represents related items in a multidimensional space. Distance between items in the multidimensional space corresponds to the extent of relationship between the items. The user can select portions of the space to perceive. The user also can interact with and control the communication of the space, focusing attention on aspects of the space of most interest. The multidimensional spatial representation allows more ready comprehension of the structure of the relationships among the items.
Gierl, Mark J.; Lai, Hollis; Pugh, Debra; Touchie, Claire; Boulais, André-Philippe; De Champlain, André
Item development is a time- and resource-intensive process. Automatic item generation integrates cognitive modeling with computer technology to systematically generate test items. To date, however, items generated using cognitive modeling procedures have received limited use in operational testing situations. As a result, the psychometric…
Lee, Yuh-shiow; Lee, Huang-mou; Fawcett, Jonathan M.
In an item-method-directed forgetting task, Chinese words were presented individually, each followed by an instruction to remember or forget. Colored probe items were presented following each memory instruction requiring a speeded color-naming response. Half of the probe items were novel and unrelated to the preceding study item, whereas the…
Wylie, Brian N.
A method for locating related items in a geometric space transforms relationships among items to geometric locations. The method locates items in the geometric space so that the distance between items corresponds to the degree of relatedness. The method facilitates communication of the structure of the relationships among the items. The method makes use of numeric values as a measure of similarity between each pairing of items. The items are given initial coordinates in the space. An energy is then determined for each item from the item's distance and similarity to other items, and from the density of items assigned coordinates near the item. The distance and similarity component can act to draw items with high similarities close together, while the density component can act to force all items apart. If a terminal condition is not yet reached, then new coordinates can be determined for one or more items, and the energy determination repeated. The iteration can terminate, for example, when the total energy reaches a threshold, when each item's energy is below a threshold, after a certain amount of time or iterations.
Wright, Keith D.; Oshima, T. C.
This study established an effect size measure for differential functioning for items and tests' noncompensatory differential item functioning (NCDIF). The Mantel-Haenszel parameter served as the benchmark for developing NCDIF's effect size measure for reporting moderate and large differential item functioning in test items. The effect size of…
... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Marking requirements for imitation... for imitation numismatic items. (a) An imitation numismatic item which is manufactured in the United... the item. (3) An imitation numismatic item of incusable material shall be incused with the word “COPY...
Fischer-Baum, Simon; McCloskey, Michael
In immediate serial recall, participants are asked to recall novel sequences of items in the correct order. Theories of the representations and processes required for this task differ in how order information is maintained; some have argued that order is represented through item-to-item associations, while others have argued that each item is…
... 26 Internal Revenue 18 2010-04-01 2010-04-01 false Consistent treatment of partnership items. 301... Consistent treatment of partnership items. (a) In general. The treatment of a partnership item on the partner's return must be consistent with the treatment of that item by the partnership on the partnership...
Ligtvoet, R.; van der Ark, L.A.; Bergsma, W. P.; Sijtsma, K.
We propose three latent scales within the framework of nonparametric item response theory for polytomously scored items. Latent scales are models that imply an invariant item ordering, meaning that the order of the items is the same for each measurement value on the latent scale. This ordering
Wang, Wen-Chung; Chen, Hui-Fang; Jin, Kuan-Yu
Many scales contain both positively and negatively worded items. Reverse recoding of negatively worded items might not be enough for them to function as positively worded items do. In this study, we commented on the drawbacks of existing approaches to wording effect in mixed-format scales and used bi-factor item response theory (IRT) models to…
Commons, C., Ed.; Martin, P., Ed.
The second volume of the Australian Chemistry Test Item Bank, consisting of two volumes, contains nearly 2000 multiple-choice items related to the chemistry taught in Year 11 and Year 12 courses in Australia. Items which were written during 1979 and 1980 were initially published in the "ACER Chemistry Test Item Collection" and in the…
van Krimpen-Stoop, Edith; Meijer, R.R.
Item scores that do not fit an assumed item response theory model may cause the latent trait value to be estimated inaccurately. For computerized adaptive tests (CAT) with dichotomous items, several person-fit statistics for detecting nonfitting item score patterns have been proposed. Both for
Polak, Marike; De Rooij, Mark; Heiser, Willem J.
In this article we propose a model-free diagnostic for single-peakedness (unimodality) of item responses. Presuming a unidimensional unfolding scale and a given item ordering, we approximate item response functions of all items based on ordered conditional means (OCM). The proposed OCM methodology is based on Thurstone & Chave's (1929) "criterion…
Liao, Wen-Wei; Ho, Rong-Guey
One of the major weaknesses of the item exposure rates of figural items in Intelligence Quotient (IQ) tests lies in its inaccuracies. In this study, a new approach is proposed and a useful test tool known as the Virtual Item Bank (VIB) is introduced. The VIB combine Automatic Item Generation theory and image processing theory with the concepts of…
The Self-Motivation Inventory (SMI) has been shown to be a predictor of exercise dropout. The original SMI of 40 items has been shortened to 10 items and the psychometric qualities of the 10-item SMI are not known. To estimate the reliability of a 10-item SMI and develop norms for an ethnically dive...
Liu, Jinghua; Zu, Jiyun; Curley, Edward; Carey, Jill
The purpose of this study is to investigate the impact of discrete anchor items versus passage-based anchor items on observed score equating using empirical data.This study compares an "SAT"® critical reading anchor that contains more discrete items proportionally, compared to the total tests to be equated, to another anchor that…
Verdam, M.G.E.; Oort, F.J.; Sprangers, M.A.G.
Purpose Comparison of patient-reported outcomes may be invalidated by the occurrence of item bias, also known as differential item functioning. We show two ways of using structural equation modeling (SEM) to detect item bias: (1) multigroup SEM, which enables the detection of both uniform and
Roelen, C.A.M.; Rhenen, van W.; Groothoff, J.W.; Klink, van der J.J.L.; Twisk, W.R.; Heymans, M.W.
Work ability predicts future disability pension (DP). A single-item work ability score (WAS) is emerging as a measure for work ability. This study compared single-item WAS with the multi-item work ability index (WAI) in its ability to identify workers at risk of DP.
Roelen, C.A.M.; van Rhenen, W.; Groothoff, J.W.; van der Klink, J.J.L.; Twisk, J.W.R.; Heymans, M.W.
Objectives Work ability predicts future disability pension (DP). A single-item work ability score (WAS) is emerging as a measure for work ability. This study compared single-item WAS with the multi-item work ability index (WAI) in its ability to identify workers at risk of DP. Methods This
Roelen, Corne A. M.; van Rhenen, Willem; Groothoff, Johan W.; van der Klink, Jac J. L.; Twisk, Jos W. R.; Heymans, Martijn W.
Objectives Work ability predicts future disability pension (DP). A single-item work ability score (WAS) is emerging as a measure for work ability. This study compared single-item WAS with the multi-item work ability index (WAI) in its ability to identify workers at risk of DP. Methods This
New South Wales Dept. of Education, Sydney (Australia).
Artmann, H.; Grau, H.; Adelmann, M.; Schleiffer, R.
Brain CT studies of 35 patients with anoxia nervosa confirmed the observations of other authors: cerebral dystrophic changes correlate with weight loss and the reversibility of these changes also correlates with the normalization of body weight. Other corroborated facts are: the most numerous and most pronounced enlargements are of the cortical sulci and the interhemispheric fissure, moderate widening affects the ventricles and the rarest and most insignificant changes are those of the cerebellum. The reversibility of the changes showed a parallel to the extent of the changes themselves and to the duration of improvement of the body weight. The reversibility of the enlargement of the cortical sulci and of the distances between the frontal horns of the lateral ventricles was more often significant than that of the abnormal measurements of the cella media. This difference is based on minimal early acquired brain damage which occurs in 60% of our patients. This high incidence of early acquired minimal brain disease in patients with anorexia nervosa is here discussed as a nonspecific predisposing factor. Although there is no exact explanation of the etiology of the reversible enlargement of cerenral spinal fluid (CSF) spaces in anorexia nervosa, the changes resemble those in alcoholics. The mechanisms of brain changes in alcoholism, as shown experimentally, seem to us to throw light on the probable mechanism of reversible dystrophic brain changes in anorexia nervosa. (orig.)
Kim, Su Jin; Lee, Jae Sung; Kim, Yu Kyeong; Lee, Dong Soo
Parametric imaging allows us analysis of the entire brain or body image. Graphical approaches are commonly employed to generate parametric imaging through linear or multilinear regression. However, this linear regression method has limited accuracy due to bias in high level of noise data. Several methods have been proposed to reduce bias for linear regression estimation especially in reversible model. In this study, we focus on generating a net accumulation rate (K i ), which is related to binding parameter in brain receptor study, parametric imaging in an irreversible compartment model using multiple linear analysis. The reliability of a newly developed multiple linear analysis method (MLAIR) was assessed through the Monte Carlo simulation, and we applied it to a [ 11 C]MeNTI PET for opioid receptor
Artmann, H.; Grau, H.; Adelmann, M.; Schleiffer, R.
Brain CT studies of 35 patients with anoxia nervosa confirmed the observations of other authors: cerebral dystrophic changes correlate with weight loss and the reversibility of these changes also correlates with the normalization of body weight. Other corroborated facts are: the most numerous and most pronounced enlargements are of the cortical sulci and the interhemispheric fissure, moderate widening affects the ventricles and the rarest and most insignificant changes are those of the cerebellum. The reversibility of the changes showed a parallel to the extent of the changes themselves and to the duration of improvement of the body weight. The reversibility of the enlargement of the cortical sulci and of the distances between the frontal horns of the lateral ventricles was more often significant than that of the abnormal measurements of the cella media. This difference is based on minimal early acquired brain damage which occurs in 60% of our patients. This high incidence of early acquired minimal brain disease in patients with anorexia nervosa is here discussed as a nonspecific predisposing factor. Although there is no exact explanation of the etiology of the reversible enlargement of cerenral spinal fluid (CSF) spaces in anorexia nervosa, the changes resemble those in alcoholics. The mechanisms of brain changes in alcoholism, as shown experimentally, seem to us to throw light on the probable mechanism of reversible dystrophic brain changes in anorexia nervosa.
McDaniel, Mark A; Cahill, Michael; Bugg, Julie M; Meadow, Nathaniel G
We apply the item-order theory of list composition effects in free recall to the orthographic distinctiveness effect. The item-order account assumes that orthographically distinct items advantage item-specific encoding in both mixed and pure lists, but at the expense of exploiting relational information present in the list. Experiment 1 replicated the typical free recall advantage of orthographically distinct items in mixed lists and the elimination of that advantage in pure lists. Supporting the item-order account, recognition performances indicated that orthographically distinct items received greater item-specific encoding than did orthographically common items in mixed and pure lists (Experiments 1 and 2). Furthermore, order memory (input-output correspondence and sequential contiguity effects) was evident in recall of pure unstructured common lists, but not in recall of unstructured distinct lists (Experiment 1). These combined patterns, although not anticipated by prevailing views, are consistent with an item-order account.
The replacement algorithm is centred on the prediction of the replacement cost and the determination of the most economical replacement policy. For items whose efficiency depreciates over their life spans e.g. machine tools, vehicles et.c; the prediction of costs involves those factors which contribute to increase operating cost, forced idle time, increase scrap, increased repair cost etc. The alternative to increased cost of operating an aging equipment is the cost of replacing the old equipment with a new one. There is some age at which the replacement of the old equipment is more economical than continuation (of the old one) at the increased operating cost (Johnson R D, Siskin B R, 1989). This algorithm uses certain cost relationships that are vital in minimization of total costs and is focused on capital equipment that depreciates with time as opposed to items with a probabilistic life span
Ip, Edward; Molenberghs, Geert; Chen, Shyh-Huei
The problem of fitting unidimensional item response models to potentially multidimensional data has been extensively studied. The focus of this article is on response data that have a strong dimension but also contain minor nuisance dimensions. Fitting a unidimensional model to such multidimensio......The problem of fitting unidimensional item response models to potentially multidimensional data has been extensively studied. The focus of this article is on response data that have a strong dimension but also contain minor nuisance dimensions. Fitting a unidimensional model...... to such multidimensional data is believed to result in ability estimates that represent a combination of the major and minor dimensions. We conjecture that the underlying dimension for the fitted unidimensional model, which we call the functional dimension, represents a nonlinear projection. In this article we investigate...... tool. An example regarding a construct of desire for physical competency is used to illustrate the functional unidimensional approach....
Chan, An-Wen; Tetzlaff, Jennifer M; Altman, Douglas G; Laupacis, Andreas; Gøtzsche, Peter C; Krle A-Jerić, Karmela; Hrobjartsson, Asbjørn; Mann, Howard; Dickersin, Kay; Berlin, Jesse A; Dore, Caroline J; Parulekar, Wendy R; Summerskill, William S M; Groves, Trish; Schulz, Kenneth F; Sox, Harold C; Rockhold, Frank W; Rennie, Drummond; Moher, David
The protocol of a clinical trial serves as the foundation for study planning, conduct, reporting, and appraisal. However, trial protocols and existing protocol guidelines vary greatly in content and quality. This article describes the systematic development and scope of SPIRIT (Standard Protocol Items: Recommendations for Interventional Trials) 2013, a guideline for the minimum content of a clinical trial protocol. The 33-item SPIRIT checklist applies to protocols for all clinical trials and focuses on content rather than format. The checklist recommends a full description of what is planned; it does not prescribe how to design or conduct a trial. By providing guidance for key content, the SPIRIT recommendations aim to facilitate the drafting of high-quality protocols. Adherence to SPIRIT would also enhance the transparency and completeness of trial protocols for the benefit of investigators, trial participants, patients, sponsors, funders, research ethics committees or institutional review boards, peer reviewers, journals, trial registries, policymakers, regulators, and other key stakeholders.
Full Text Available In recent years, recommender systems (RS provide a considerable progress to users. RSs reduce the cost of a user’s time in order to reach to desired results faster. The main issue of RSs is the presence of cold users which are less active and their preferences are more difficult to detect. The aim of this study is to provide a new way to improve recall and precision in recommender systems for cold users. According to the available categories of items, prioritization of the proposed items is improved and then presented to the cold user. The obtained results show that in addition to increased speed of processing, recall and precision have an acceptable improvement.
Gerard van der Laan
Full Text Available Several heterogeneous items are to be sold to a group of potentially budget- constrained bidders. Every bidder has private knowledge of his own valuation of the items and his own budget. Due to budget constraints, bidders may not be able to pay up to their values and typically no Walrasian equilibrium exists. To deal with such markets, we propose the notion of 'equilibrium under allotment' and develop an ascending auction mechanism that always finds such an equilibrium assignment and a corresponding system of prices in finite time. The auction can be viewed as a novel generalization of the ascending auction of Demange et al. (1986 from settings without financial constraints to settings with financial constraints. We examine various strategic and efficiency properties of the auction and its outcome.
Analytical work on material of archaeological interest performed at LARN mainly concerns gold jewellery, with an emphasis to solders on the artefacts and to gold plating or copper depletion gilding. PIXE, RBS but also PIGE and NRA have been applied to a large variety of items. On the basis of elemental analysis, we have identified typical workmanship of ancient goldsmiths in various regions of the world: finely decorated Mesopotamian items, Hellenistic and Byzantine craftsmanship, cloisonne of the Merovingian period, depletion gilding on Pre-Colombian tumbaga. This paper is some shortening of the work performed at LARN during the last ten years. Criteria to properly use PIXE for quantitative analysis of non-homogeneous ancient artefacts presented at the 12th IBA conference in 1995 are also shortly discussed. (orig.)
Demortier, G [Facultes Universitaires Notre-Dame de la Paix, Namur (Belgium). Lab. d` Analyses par Reactions Nucleaires
Analytical work on material of archaeological interest performed at LARN mainly concerns gold jewellery, with an emphasis to solders on the artefacts and to gold plating or copper depletion gilding. PIXE, RBS but also PIGE and NRA have been applied to a large variety of items. On the basis of elemental analysis, we have identified typical workmanship of ancient goldsmiths in various regions of the world: finely decorated Mesopotamian items, Hellenistic and Byzantine craftsmanship, cloisonne of the Merovingian period, depletion gilding on Pre-Colombian tumbaga. This paper is some shortening of the work performed at LARN during the last ten years. Criteria to properly use PIXE for quantitative analysis of non-homogeneous ancient artefacts presented at the 12th IBA conference in 1995 are also shortly discussed. (orig.).
Schmidt, Stephen R; Saari, Bonnie
A color-naming task was followed by incidental free recall to investigate how emotional words affect attention and memory. We compared taboo, nonthreatening negative-affect, and neutral words across three experiments. As compared with neutral words, taboo words led to longer color-naming times and better memory in both within- and between-subjects designs. Color naming of negative-emotion nontaboo words was slower than color naming of neutral words only during block presentation and at relatively short interstimulus intervals (ISIs). The nontaboo emotion words were remembered better than neutral words following blocked and random presentation and at both long and short ISIs, but only in mixed-list designs. Our results support multifactor theories of the effects of emotion on attention and memory. As compared with neutral words, threatening stimuli received increased attention, poststimulus elaboration, and benefit from item distinctiveness, whereas nonthreatening emotional stimuli benefited only from increased item distinctiveness.
Chalmers, R Philip; Pek, Jolynn; Liu, Yang
Confidence intervals (CIs) are fundamental inferential devices which quantify the sampling variability of parameter estimates. In item response theory, CIs have been primarily obtained from large-sample Wald-type approaches based on standard error estimates, derived from the observed or expected information matrix, after parameters have been estimated via maximum likelihood. An alternative approach to constructing CIs is to quantify sampling variability directly from the likelihood function with a technique known as profile-likelihood confidence intervals (PL CIs). In this article, we introduce PL CIs for item response theory models, compare PL CIs to classical large-sample Wald-type CIs, and demonstrate important distinctions among these CIs. CIs are then constructed for parameters directly estimated in the specified model and for transformed parameters which are often obtained post-estimation. Monte Carlo simulation results suggest that PL CIs perform consistently better than Wald-type CIs for both non-transformed and transformed parameters.
Matthew S. Johnson
Full Text Available Item response theory (IRT models are a class of statistical models used by researchers to describe the response behaviors of individuals to a set of categorically scored items. The most common IRT models can be classified as generalized linear fixed- and/or mixed-effect models. Although IRT models appear most often in the psychological testing literature, researchers in other fields have successfully utilized IRT-like models in a wide variety of applications. This paper discusses the three major methods of estimation in IRT and develops R functions utilizing the built-in capabilities of the R environment to find the marginal maximum likelihood estimates of the generalized partial credit model. The currently available R packages ltm is also discussed.
Lindwall, Magnus; Barkoukis, Vassilis; Grano, Caterina; Lucidi, Fabio; Raudsepp, Lennart; Liukkonen, Jarmo; Thøgersen-Ntoumani, Cecilie
Using confirmatory factor analyses, we examined method effects on Rosenberg's Self-Esteem Scale (RSES; Rosenberg, 1965) in a sample of older European adults. Nine hundred forty nine community-dwelling adults 60 years of age or older from 5 European countries completed the RSES as well as measures of depression and life satisfaction. The 2 models that had an acceptable fit with the data included method effects. The method effects were associated with both positively and negatively worded items. Method effects models were invariant across gender and age, but not across countries. Both depression and life satisfaction predicted method effects. Individuals with higher depression scores and lower life satisfaction scores were more likely to endorse negatively phrased items.
Food items locally grown near Perth, Ontario and grocery store produce and locally grown items from the Pickering-Ajax area in the vicinity of the Pickering Nuclear Generating Station (PNGS) have been analyzed for free water tritium (HTO) and organically bound tritium (OBT). The technique of measuring 3 He ingrowth in samples by mass spectrometry has been used because of its sensitivity and freedom from opportunity for contamination during processing and measurement. Concentrations observed at each site were of the order expected on the basis of known levels of tritium in the local atmosphere and precipitation. There was considerable variation between different materials and limited correlation between materials of a single type. (author). 10 refs., 8 tabs., 4 figs
Khedlekar, Uttam Kumar; Shukla, Diwakar; Namdeo, Anubhav
We have designed an inventory model for seasonal products in which deterioration can be controlled by item preservation technology investment. Demand for the product is considered price sensitive and decreases linearly. This study has shown that the profit is a concave function of optimal selling price, replenishment time and preservation cost parameter. We simultaneously determined the optimal selling price of the product, the replenishment cycle and the cost of item preservation technology. Additionally, this study has shown that there exists an optimal selling price and optimal preservation investment to maximize the profit for every business set-up. Finally, the model is illustrated by numerical examples and sensitive analysis of the optimal solution with respect to major parameters.
Seyed Reza Moosavi Tabatabaei
Full Text Available Optimal pricing and marketing planning plays an essential role in production decisions on deteriorating items. This paper presents a mathematical model for a three-level supply chain, which includes one producer, one distributor and one retailer. The proposed study considers the production of a deteriorating item where demand is influenced by price, marketing expenditure, quality of product and after-sales service expenditures. The proposed model is formulated as a geometric programming with 5 degrees of difficulty and the problem is solved using the recent advances in optimization techniques. The study is supported by several numerical examples and sensitivity analysis is performed to analyze the effects of the changes in different parameters on the optimal solution. The preliminary results indicate that with the change in parameters influencing on demand, inventory holding, inventory deteriorating and set-up costs change and also significantly affect total revenue.
Moosavi Tabatabaei, Seyed Reza; Sadjadi, Seyed Jafar; Makui, Ahmad
Optimal pricing and marketing planning plays an essential role in production decisions on deteriorating items. This paper presents a mathematical model for a three-level supply chain, which includes one producer, one distributor and one retailer. The proposed study considers the production of a deteriorating item where demand is influenced by price, marketing expenditure, quality of product and after-sales service expenditures. The proposed model is formulated as a geometric programming with 5 degrees of difficulty and the problem is solved using the recent advances in optimization techniques. The study is supported by several numerical examples and sensitivity analysis is performed to analyze the effects of the changes in different parameters on the optimal solution. The preliminary results indicate that with the change in parameters influencing on demand, inventory holding, inventory deteriorating and set-up costs change and also significantly affect total revenue. PMID:28306750
Benameur, Azzedine; Khoury, Paul El; Seguran, Magali; Sinha, Smriti Kumar
SERENITY Artefacts, like Class, Patterns, Implementations and Executable Components for Security & Dependability (S&D) in addition to Serenity Runtime Framework (SRF) are discussed in previous chapters. How to integrate these artefacts with applications in Serenity approach is discussed here with two scenarios. The e-Business scenario is a standard loan origination process in a bank. The Smart Item scenario is an Ambient intelligence case study where we take advantage of Smart Items to provide an electronic healthcare infrastructure for remote healthcare assistance. In both cases, we detail how the prototype implementations of the scenarios select proper executable components through Serenity Runtime Framework and then demonstrate how these executable components of the S&D Patterns are deployed.
Moosavi Tabatabaei, Seyed Reza; Sadjadi, Seyed Jafar; Makui, Ahmad
Optimal pricing and marketing planning plays an essential role in production decisions on deteriorating items. This paper presents a mathematical model for a three-level supply chain, which includes one producer, one distributor and one retailer. The proposed study considers the production of a deteriorating item where demand is influenced by price, marketing expenditure, quality of product and after-sales service expenditures. The proposed model is formulated as a geometric programming with 5 degrees of difficulty and the problem is solved using the recent advances in optimization techniques. The study is supported by several numerical examples and sensitivity analysis is performed to analyze the effects of the changes in different parameters on the optimal solution. The preliminary results indicate that with the change in parameters influencing on demand, inventory holding, inventory deteriorating and set-up costs change and also significantly affect total revenue.
Automatic item generation (AIG) is a broad class of methods that are being developed to address psychometric issues arising from internet and computer-based testing. In general, issues emphasize efficiency, validity, and diagnostic usefulness of large scale mental testing. Rapid prominence of AIG methods and their implicit perspective on mental testing is bringing painful scrutiny to many sacred psychometric assumptions. This report reviews basic AIG ideas, then presents conceptual foundations, image model development, and operational application to artistic judgment aptitude testing.
Gold, Jeffrey J.; Hopkins, Ramona O.; Squire, Larry R.
We tested recognition memory for items and associations in memory-impaired patients with bilateral lesions thought to be limited to the hippocampal region. In Experiment 1 (Combined memory test), participants studied words and then took a memory test in which studied words, new words, studied word pairs, and recombined word pairs were presented in a mixed order. In Experiment 2 (Separated memory test), participants studied single words and then took a memory test involving studied word and ne...
Hua, Sophia V; Ickovics, Jeannette R
Vending machines are a ubiquitous part of our food environments. Unfortunately, items found in vending machines tend to be processed foods and beverages high in salt, sugar, and/or fat. The purpose of this review is to describe intervention and case studies designed to promote healthier vending purchases by consumers and identify which manipulations are most effective. All studies analyzed were intervention or case studies that manipulated vending machines and analyzed sales or revenue data. This literature review is limited to studies conducted in the United States within the past 2 decades (ie, 1994 to 2015), regardless of study population or setting. Ten articles met these criteria based on a search conducted using PubMed. Study manipulations included price changes, increase in healthier items, changes to the advertisements wrapped around vending machines, and promotional signs such as a stoplight system to indicate healthfulness of items and to remind consumers to make healthy choices. Overall, seven studies had manipulations that resulted in statistically significant positive changes in purchasing behavior. Two studies used manipulations that did not influence consumer behavior, and one study was equivocal. Although there was no intervention pattern that ensured changes in purchasing, price reductions were most effective overall. Revenue from vending sales did not change substantially regardless of intervention, which will be important to foster initiation and sustainability of healthier vending. Future research should identify price changes that would balance healthier choices and revenue as well as better marketing to promote purchase of healthier items. Copyright © 2016 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.
Yong He; Ju He
Disruption management has recently become an active area of research. In this study, an extension is made to consider the fact that some products may deteriorate during storage. A production-inventory model for deteriorating items with production disruptions is developed. Then the optimal production and inventory plans are provided, so that the manufacturer can reduce the loss caused by disruptions. Finally, a numerical example is used to illustrate the model.
Schoeneman, J.L.; Baumann, M.J.; Fox, L.J.; Jenkins, C.D.; Perlinsk, A.W.
Sandia National Laboratories (SNL) is in the final stages of developing a Universal Authenticated Item Monitoring System (AIMS). When completed, AIMS will provide applicable agencies in the US government, and those in the International arena, with a secure and convenient method of monitoring the physical status of selected items. The benefit derived from this development activity will be the commercial availability of an item monitoring system with the capability for ''quick set-up'' monitoring, as well as long-term unattended monitoring. The AIMS includes a variety of sensors, a robust and authenticated radio frequency (RF) communication link, a Receiver Processing Unit (RPU), and an inspector-friendly personal computer (PC) interface for collecting, sorting, viewing and archiving pertinent event histories. The system will provide the capability to monitor selected items in a real-time mode, a remotely interrogated mode, and a stand-alone, unattended data collection mode. The sensor suite under development includes advanced motion sensors, interior volumetric intrusion sensors, Re-usable, In-situ Verifiable Authenticated (RIVA) fiber-optic seal sensors, generic utility sensors (to accommodate contact closure inputs), and radiation and environmental sensors. A new generation authentication algorithm recently has been developed that provides a high degree of system security 121. The AIMS has potential safeguards applications in the areas of arms control and treaty verification military asset control, International Atomic Energy Agency (IAEA) and Euratom safeguards verification activities, as well as domestic nuclear safeguard activities. Commercial applications could include high-value inventory control and security systems. This paper describes the second-generation AIMS along with its recently expanded sensor suite and enhanced data collection capabilities
Palmer, J.; Lock, Peter
Peter Lock described some particular cases which had given rise to difficult acceptance issues at NIREX, ranging from large size items to the impacts of chemicals used during decontamination on the mobility of radionuclides in a disposal facility: The UK strategy for intermediate level and certain low level radioactive waste disposal is based on production of cementitious waste-forms packaged in a standard range of containers as follows: 500 litre Drum - the normal container for most operational ILW (0.8 m diameter x 1.2 m high); 3 m"3 Box - a larger container for solid wastes (1.72 m x 1.72 m plan x 1.2 m high); 3 m"3 Drum - a larger container for in-drum mixing and immobilisation of sludge waste-forms (1.72 m diameter x 1.2 m high); 4 m Box - for large items of waste, especially from decommissioning (4.0 m x 2.4 m plan x 2.2 m high); 2 m LLW Box - for higher-density wastes (2.0 m x 2.4 m plan x 2.2 m high). In addition the majority of LLW is packaged by supercompaction followed by grouting in modified ISO freight containers (6 m x 2.5 m x 2.5 m). Some wastes do not fit easily into this strategy. These wastes include: very large items, (too big for the 4 m box) which, if dealt with whole, pose transport and disposal problems. These items are discussed further in Section 2; waste whose characteristics make packaging difficult. Such wastes are described in more detail in Section 3
Pilkonis, Paul A; Kim, Yookyung; Yu, Lan; Morse, Jennifer Q
The Adult Attachment Ratings (AAR) include 3 scales for anxious, ambivalent attachment (excessive dependency, interpersonal ambivalence, and compulsive care-giving), 3 for avoidant attachment (rigid self-control, defensive separation, and emotional detachment), and 1 for secure attachment. The scales include items (ranging from 6-16 in their original form) scored by raters using a 3-point format (0 = absent, 1 = present, and 2 = strongly present) and summed to produce a total score. Item response theory (IRT) analyses were conducted with data from 414 participants recruited from psychiatric outpatient, medical, and community settings to identify the most informative items from each scale. The IRT results allowed us to shorten the scales to 5-item versions that are more precise and easier to rate because of their brevity. In general, the effective range of measurement for the scales was 0 to +2 SDs for each of the attachment constructs; that is, from average to high levels of attachment problems. Evidence for convergent and discriminant validity of the scales was investigated by comparing them with the Experiences of Close Relationships-Revised (ECR-R) scale and the Kobak Attachment Q-sort. The best consensus among self-reports on the ECR-R, informant ratings on the ECR-R, and expert judgments on the Q-sort and the AAR emerged for anxious, ambivalent attachment. Given the good psychometric characteristics of the scale for secure attachment, however, this measure alone might provide a simple alternative to more elaborate procedures for some measurement purposes. Conversion tables are provided for the 7 scales to facilitate transformation from raw scores to IRT-calibrated (theta) scores.
Composite assessments aim to combine different aspects of a disease in a single score and are utilized in a variety of therapeutic areas. The data arising from these evaluations are inherently discrete with distinct statistical properties. This tutorial presents the framework of the item response theory (IRT) for the analysis of this data type in a pharmacometric context. The article considers both conceptual (terms and assumptions) and practical questions (modeling software, data requirements, and model building). PMID:29493119
Wang Hongjun; Chen Desheng
The constitution of nuclear safeguards data flow for the item facilities is introduced and the main contents are the data flow of nuclear safeguards. If the data flow moves positively, i.e. from source data →supporting documents→accounting records→accounting reports, the systems of records and reports will be constituted. If the data flow moves negatively, the way to trace inspection of nuclear material accounting quality will be constituted
... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true Types of shelf-life items...-Management of Shelf-Life Materials § 101-27.204 Types of shelf-life items. Shelf-life items are classified as nonextendable (Type I) and extendable (Type II). Type I items have a definite storage life after which the item...
Nisa, A.U.; Hina, S.; Ejaz, N.
The present study was conducted to quantify and detoxify the antitoxins in food items. For this purpose, total 30 samples of food were collected. The samples were quantified using thin layer chromatography (TLC) for the presence of aflatoxin level in food items. Out of them aflatoxins were not found in 10 samples. Remaining 20 aflatoxins +ve samples were treated with various chemical solutions i.e. 0.1% HCl, 0.3%HCl, 0.5% HCI, 10% citric acid, 30% citric acid, 50% calcium hydroxide, 0.2 and 0.3% NaOCl, 96% ethanol and 99% acetone for detoxification. The aflatoxins were reduced to 55.1%, 90.9%, 28.08% and 80.0% in Super Sella rice, Super Basmati rice, Brown rice and White rice, respectively. The aflatoxin level was reduced in maize grain, damaged wheat, peanut, figs and dates upto 31.3 %, 64.3 %, 63.6%, 42.7% and 19.8%, respectively. Aflatoxins were detoxified in cereals Dal Chana, Dal Mash, Dal Masoor, turmeric (Haldi) and Nigela seeds (Kalwangi) upto 70.5%, 83.0%, 46.2%, 82.09% and 36.9%, respectively. Reduction of aflatoxins was carried out 39.7 %,7.l % 39.5% 82.0% and 62.0% in red chilli, makhana, corn flakes, desert (Kheer Mix) and pistachio. The significant results (p = 0.042) of detoxification of aflatoxins in food items were obtained from present study. (author)
Some manufacturers and suppliers use inferior materials and processes to make substandard supplies whose properties can vary significantly from established standards and specifications. Other suppliers distribute items that they know do not meet the purchase requirements or provide documentation that misrepresent actual conformance to established specifications and standards. These substandard supplies, or suspect/counterfeit items (S/CIs), pose potential threats to the safety of workers, the public and the environment and may also have a detrimental effect on security and operations at nuclear facilities. Nuclear facilities often procure and use commercial-grade items and the quality assurance policies/procedures and procurement methods are not always properly applied to avoid the entry of S/Cls into those facilities. This publication offers practical guidance on how to apply existing quality assurance programmes to effectively prevent the procurement and use of S/Cls. In particular, it provides a practical method of applying the requirements and guidance contained in the IAEA Safety Series 50-C/SG-Q: Code and Safety Guides on Quality Assurance for Safety in Nuclear Power Plants and other Nuclear Installations (1996), to the S/CIs issue
Nisa, A. U.; Hina, S.; Ejaz, N. [Pakistan Council of Scientific and Industrial Research Laboratories, Lahore (Pakistan). Dept. of Food and Biotechnology
The present study was conducted to quantify and detoxify the antitoxins in food items. For this purpose, total 30 samples of food were collected. The samples were quantified using thin layer chromatography (TLC) for the presence of aflatoxin level in food items. Out of them aflatoxins were not found in 10 samples. Remaining 20 aflatoxins +ve samples were treated with various chemical solutions i.e. 0.1% HCl, 0.3%HCl, 0.5% HCI, 10% citric acid, 30% citric acid, 50% calcium hydroxide, 0.2 and 0.3% NaOCl, 96% ethanol and 99% acetone for detoxification. The aflatoxins were reduced to 55.1%, 90.9%, 28.08% and 80.0% in Super Sella rice, Super Basmati rice, Brown rice and White rice, respectively. The aflatoxin level was reduced in maize grain, damaged wheat, peanut, figs and dates upto 31.3 %, 64.3 %, 63.6%, 42.7% and 19.8%, respectively. Aflatoxins were detoxified in cereals Dal Chana, Dal Mash, Dal Masoor, turmeric (Haldi) and Nigela seeds (Kalwangi) upto 70.5%, 83.0%, 46.2%, 82.09% and 36.9%, respectively. Reduction of aflatoxins was carried out 39.7 %,7.l % 39.5% 82.0% and 62.0% in red chilli, makhana, corn flakes, desert (Kheer Mix) and pistachio. The significant results (p = 0.042) of detoxification of aflatoxins in food items were obtained from present study. (author)
Full Text Available The outset of new technologies, systems and applications in manufacturing sector has no doubt lighten up our workload, yet the chance causes of variation in production system cannot be eliminated completely. Every produced/ordered lot may have some fraction of defectives which may vary from process to process. In addition the situation is more susceptible when the items are deteriorating in nature. However, the defective items can be secluded from the good quality lot through a careful inspection process. Thus, a screening process is obligatory in today’s technology driven industry which has the customer satisfaction as its only motto. Moreover, in order to survive in the current global markets, credit financing has been proven a very influential promotional tool to attract new customers and a good inducement policy for the retailers. Keeping this scenario in mind, the present paper investigates an inventory model for a retailer dealing with imperfect quality deteriorating items under permissible delay in payments. Shortages are allowed and fully backlogged. This model jointly optimizes the order quantity and shortages by maximizing the expected total profit. A mathematical model is developed to depict this scenario. Results have been validated with the help of numerical example. Comprehensive sensitivity analysis has also been presented.
Fox, Jean-Paul; Mulder, Joris; Sinharay, Sandip
Two marginal one-parameter item response theory models are introduced, by integrating out the latent variable or random item parameter. It is shown that both marginal response models are multivariate (probit) models with a compound symmetry covariance structure. Several common hypotheses concerning the underlying covariance structure are evaluated using (fractional) Bayes factor tests. The support for a unidimensional factor (i.e., assumption of local independence) and differential item functioning are evaluated by testing the covariance components. The posterior distribution of common covariance components is obtained in closed form by transforming latent responses with an orthogonal (Helmert) matrix. This posterior distribution is defined as a shifted-inverse-gamma, thereby introducing a default prior and a balanced prior distribution. Based on that, an MCMC algorithm is described to estimate all model parameters and to compute (fractional) Bayes factor tests. Simulation studies are used to show that the (fractional) Bayes factor tests have good properties for testing the underlying covariance structure of binary response data. The method is illustrated with two real data studies.
Ebrahimi, Amrollah; Samouei, Rahele; Mousavii, Sayyed Ghafour; Bornamanesh, Ali Reza
Dysfunctional Attitude Scale is one of the most common instruments used to assess cognitive vulnerability. This study aimed to develop and validate a short form of Dysfunctional Attitude Scale appropriate for an Iranian clinical population. Participants were 160 psychiatric patients from medical centers affiliated with Isfahan Medical University, as well as 160 non-patients. Research instruments were clinical interviews based on the Diagnostic and Statistical Manual-IV-TR, Dysfunctional Attitude Scale and General Heath Questionnaire (GHQ-28). Data was analyzed using multicorrelation calculations and factor analysis. Based on the results of factor analysis and item-total correlation, 14 items were judged candidates for omission. Analysis of the 26-item Dysfunctional Attitude Scale (DAS-26) revealed a Cronbach's alpha of 0.92. Evidence for the concurrent criterion validity was obtained through calculating the correlation between the Dysfunctional Attitude Scale and psychiatric diagnosis (r = 0.55), GHQ -28 (r = 0.56) and somatization, anxiety, social dysfunction, and depression subscales (0.45,0.53,0.48, and 0.57, respectively). Factor analysis deemed a four-factor structure the best. The factors were labeled as success-perfectionism, need for approval, need for satisfying others, and vulnerability-performance evaluation. The results showed that the Iranian version of the Dysfunctional Attitude Scale (DAS-26) bears satisfactory psychometric properties suggesting that this cognitive instrument is appropriate for use in an Iranian cultural context. Copyright © 2012 Wiley Publishing Asia Pty Ltd.
Lai, Hollis; Gierl, Mark J; Byrne, B Ellen; Spielman, Andrew I; Waldschmidt, David M
Test items created for dentistry examinations are often individually written by content experts. This approach to item development is expensive because it requires the time and effort of many content experts but yields relatively few items. The aim of this study was to describe and illustrate how items can be generated using a systematic approach. Automatic item generation (AIG) is an alternative method that allows a small number of content experts to produce large numbers of items by integrating their domain expertise with computer technology. This article describes and illustrates how three modeling approaches to item content-item cloning, cognitive modeling, and image-anchored modeling-can be used to generate large numbers of multiple-choice test items for examinations in dentistry. Test items can be generated by combining the expertise of two content specialists with technology supported by AIG. A total of 5,467 new items were created during this study. From substitution of item content, to modeling appropriate responses based upon a cognitive model of correct responses, to generating items linked to specific graphical findings, AIG has the potential for meeting increasing demands for test items. Further, the methods described in this study can be generalized and applied to many other item types. Future research applications for AIG in dental education are discussed.
Wei B. Mao
Full Text Available Showing an emotional item in a neutral background scene often leads to enhanced memory for the emotional item and impaired associative memory for background details. Meanwhile, both top–down goal relevance and bottom–up perceptual features played important roles in memory binding. We conducted two experiments and aimed to further examine the effects of goal relevance and perceptual features on emotional items and associative memory. By manipulating goal relevance (asking participants to categorize only each item image as living or non-living or to categorize each whole composite picture consisted of item image and background scene as natural scene or manufactured scene and perceptual features (controlling visual contrast and visual familiarity in two experiments, we found that both high goal relevance and salient perceptual features (high salience of items vs. high familiarity of items could promote emotional item memory, but they had different effects on associative memory for emotional items and neutral backgrounds. Specifically, high goal relevance and high perceptual-salience of items could jointly impair the associative memory for emotional items and neutral backgrounds, while the effect of item familiarity on associative memory for emotional items would be modulated by goal relevance. High familiarity of items could increase associative memory for negative items and neutral backgrounds only in the low goal relevance condition. These findings suggest the effect of emotion on associative memory is not only related to attentional capture elicited by emotion, but also can be affected by goal relevance and perceptual features of stimulus.
Mao, Wei B; An, Shu; Yang, Xiao F
Showing an emotional item in a neutral background scene often leads to enhanced memory for the emotional item and impaired associative memory for background details. Meanwhile, both top-down goal relevance and bottom-up perceptual features played important roles in memory binding. We conducted two experiments and aimed to further examine the effects of goal relevance and perceptual features on emotional items and associative memory. By manipulating goal relevance (asking participants to categorize only each item image as living or non-living or to categorize each whole composite picture consisted of item image and background scene as natural scene or manufactured scene) and perceptual features (controlling visual contrast and visual familiarity) in two experiments, we found that both high goal relevance and salient perceptual features (high salience of items vs. high familiarity of items) could promote emotional item memory, but they had different effects on associative memory for emotional items and neutral backgrounds. Specifically, high goal relevance and high perceptual-salience of items could jointly impair the associative memory for emotional items and neutral backgrounds, while the effect of item familiarity on associative memory for emotional items would be modulated by goal relevance. High familiarity of items could increase associative memory for negative items and neutral backgrounds only in the low goal relevance condition. These findings suggest the effect of emotion on associative memory is not only related to attentional capture elicited by emotion, but also can be affected by goal relevance and perceptual features of stimulus.
International Thermonuclear Experimental Reactor (ITER) project, as the most large-scale science project and research cooperation plan in the human history, has brought together major world-wide scientific and technological achievements in current controlled magnetic confinement fusion research. The project is aiming at validating the scientific and technological feasibility of the peaceful use of fusion energy, laying a science and technology foundation for the realization of the fusion energy commercialization. Promoted by the ITER project, the nuclear fusion frontier science researches and experiments in China have made a deep development, and have made remarkable achievements. Based on this situation, the Fusion Information Division of the Southwestern Institute of Physics (SWIP) has undertaken the soft science research task item -Prediction of Nuclear Fusion Energy Research and Development Technology in China,issued by the Ministry of Science and Technology of China. The research team has gone through these processes such as documentation collection and investigation, documentation reading and refining, outline determination, the first draft writing, content analysis and optimization for the draft, and the internal trial within the research team, review and revise from the experts at SWIP and out of SWIP, evaluation from China International Nuclear Fusion Energy Program Execution Center (ITER China DA), as well as evaluation from the famous experts in domestic fusion community by means of letters and mail. Finally, the research team has completed the research report successfully. In this report, the fusion development strategies of the world's leading fusion research countries and organizations participating in ITER project have been described. Moreover, some comparisons and analysis in this report have been made in order to provide scientific and technological research, analysis base, as well as strategic decision references for exploring medium and long term
Xi, Xiaopeng; Chen, Maoyin; Zhang, Hanwen; Zhou, Donghua
It is widely noted in the literature that the degradation should be simplified into a memoryless Markovian process for the purpose of predicting the remaining useful life (RUL). However, there actually exists the long-term dependency in the degradation processes of some industrial systems, including electromechanical equipments, oil tankers, and large blast furnaces. This implies the new degradation state depends not only on the current state, but also on the historical states. Such dynamic systems cannot be accurately described by traditional Markovian models. Here we present an improved non-Markovian degradation model with both the long-term dependency and the item-to-item uncertainty. As a typical non-stationary process with dependent increments, fractional Brownian motion (FBM) is utilized to simulate the fractal diffusion of practical degradations. The uncertainty among multiple items can be represented by a random variable of the drift. Based on this model, the unknown parameters are estimated through the maximum likelihood (ML) algorithm, while a closed-form solution to the RUL distribution is further derived using a weak convergence theorem. The practicability of the proposed model is fully verified by two real-world examples. The results demonstrate that the proposed method can effectively reduce the prediction error.
Harrison, Peter M C; Collins, Tom; Müllensiefen, Daniel
Modern psychometric theory provides many useful tools for ability testing, such as item response theory, computerised adaptive testing, and automatic item generation. However, these techniques have yet to be integrated into mainstream psychological practice. This is unfortunate, because modern psychometric techniques can bring many benefits, including sophisticated reliability measures, improved construct validity, avoidance of exposure effects, and improved efficiency. In the present research we therefore use these techniques to develop a new test of a well-studied psychological capacity: melodic discrimination, the ability to detect differences between melodies. We calibrate and validate this test in a series of studies. Studies 1 and 2 respectively calibrate and validate an initial test version, while Studies 3 and 4 calibrate and validate an updated test version incorporating additional easy items. The results support the new test's viability, with evidence for strong reliability and construct validity. We discuss how these modern psychometric techniques may also be profitably applied to other areas of music psychology and psychological science in general.
Tijmstra, Jesper; Bolsinova, Maria; Jeon, Minjeong
This article proposes a general mixture item response theory (IRT) framework that allows for classes of persons to differ with respect to the type of processes underlying the item responses. Through the use of mixture models, nonnested IRT models with different structures can be estimated for different classes, and class membership can be estimated for each person in the sample. If researchers are able to provide competing measurement models, this mixture IRT framework may help them deal with some violations of measurement invariance. To illustrate this approach, we consider a two-class mixture model, where a person's responses to Likert-scale items containing a neutral middle category are either modeled using a generalized partial credit model, or through an IRTree model. In the first model, the middle category ("neither agree nor disagree") is taken to be qualitatively similar to the other categories, and is taken to provide information about the person's endorsement. In the second model, the middle category is taken to be qualitatively different and to reflect a nonresponse choice, which is modeled using an additional latent variable that captures a person's willingness to respond. The mixture model is studied using simulation studies and is applied to an empirical example.
Thibodeau, Michel A; Leonard, Rachel C; Abramowitz, Jonathan S; Riemann, Bradley C
The Dimensional Obsessive-Compulsive Scale (DOCS) is a promising measure of obsessive-compulsive disorder (OCD) symptoms but has received minimal psychometric attention. We evaluated the utility and reliability of DOCS scores. The study included 832 students and 300 patients with OCD. Confirmatory factor analysis supported the originally proposed four-factor structure. DOCS total and subscale scores exhibited good to excellent internal consistency in both samples (α = .82 to α = .96). Patient DOCS total scores reduced substantially during treatment (t = 16.01, d = 1.02). DOCS total scores discriminated between students and patients (sensitivity = 0.76, 1 - specificity = 0.23). The measure did not exhibit gender-based differential item functioning as tested by Mantel-Haenszel chi-square tests. Expected response options for each item were plotted as a function of item response theory and demonstrated that DOCS scores incrementally discriminate OCD symptoms ranging from low to extremely high severity. Incremental differences in DOCS scores appear to represent unbiased and reliable differences in true OCD symptom severity. © The Author(s) 2014.
Bae, Gi Yeul; Flombaum, Jonathan I
In the ongoing debate about the efficacy of visual working memory for more than three items, a consensus has emerged that memory precision declines as memory load increases from one to three. Many studies have reported that memory precision seems to be worse for two items than for one. We argue that memory for two items appears less precise than that for one only because two items present observers with a correspondence challenge that does not arise when only one item is stored--the need to relate observations to their corresponding memory representations. In three experiments, we prevented correspondence errors in two-item trials by varying sample items along task-irrelevant but integral (as opposed to separable) dimensions. (Initial experiments with a classic sorting paradigm identified integral feature relationships.) In three memory experiments, our manipulation produced equally precise representations of two items and of one item.
Prem Senthil, Mallika; Khadka, Jyoti; De Roach, John; Lamey, Tina; McLaren, Terri; Campbell, Isabella; Fenwick, Eva K; Lamoureux, Ecosse L; Pesudovs, Konrad
Our understanding of the coping strategies used by people with visual impairment to manage stress related to visual loss is limited. This study aims to develop a sophisticated coping instrument in the form of an item bank implemented via Computerised adaptive testing (CAT) for hereditary retinal diseases. Items on coping were extracted from qualitative interviews with patients which were supplemented by items from a literature review. A systematic multi-stage process of item refinement was carried out followed by expert panel discussion and cognitive interviews. The final coping item bank had 30 items. Rasch analysis was used to assess the psychometric properties. A CAT simulation was carried out to estimate an average number of items required to gain precise measurement of hereditary retinal disease-related coping. One hundred eighty-nine participants answered the coping item bank (median age = 58 years). The coping scale demonstrated good precision and targeting. The standardised residual loadings for items revealed six items grouped together. Removal of the six items reduced the precision of the main coping scale and worsened the variance explained by the measure. Therefore, the six items were retained within the main scale. Our CAT simulation indicated that, on average, less than 10 items are required to gain a precise measurement of coping. This is the first study to develop a psychometrically robust coping instrument for hereditary retinal diseases. CAT simulation indicated that on an average, only four and nine items were required to gain measurement at moderate and high precision, respectively.
Full Text Available Based on nonlinear models between the measured latent variable and the item response, item response theory (IRT enables independent estimation of item and person parameters and local estimation of measurement error. These properties of IRT are also the main theoretical advantages of IRT over classical test theory (CTT. Empirical evidence, however, often failed to discover consistent differences between IRT and CTT parameters and between invariance measures of CTT and IRT parameter estimates. In this empirical study a real data set from the Third International Mathematics and Science Study (TIMSS 1995 was used to address the following questions: (1 How comparable are CTT and IRT based item and person parameters? (2 How invariant are CTT and IRT based item parameters across different participant groups? (3 How invariant are CTT and IRT based item and person parameters across different item sets? The findings indicate that the CTT and the IRT item/person parameters are very comparable, that the CTT and the IRT item parameters show similar invariance property when estimated across different groups of participants, that the IRT person parameters are more invariant across different item sets, and that the CTT item parameters are at least as much invariant in different item sets as the IRT item parameters. The results furthermore demonstrate that, with regards to the invariance property, IRT item/person parameters are in general empirically superior to CTT parameters, but only if the appropriate IRT model is used for modelling the data.
Phillips, Steven; Niki, Kazuhisa
Working memory is affected by items stored and the relations between them. However, separating these factors has been difficult, because increased items usually accompany increased associations/relations. Hence, some have argued, relational effects are reducible to item effects. We overcome this problem by manipulating index length: the fewest number of item positions at which there is a unique item, or tuple of items (if length >1), for every instance in the relational (memory) set. Longer indexes imply greater similarity (number of shared items) between instances and higher load on encoding processes. Subjects were given lists of study pairs and asked to make a recognition judgement. The number of unique items and index length in the three list conditions were: (1) AB, CD: four/one; (2) AB, CD, EF: six/one; and (3) AB, AD, CB: four/two, respectively. Japanese letters were used in Experiments 1 (kanji-ideograms) and 2 (hiragana-phonograms); numbers in Experiment 3; and shapes generated from Fourier descriptors in Experiment 4. Across all materials, right dominant temporoparietal and middle frontal gyral activity was found with increased index length, but not items during study. In Experiment 5, a longer delay was used to isolate retention effects in the absence of visual stimuli. Increased left hemispheric activity was observed in the precuneus, middle frontal gyrus, and superior temporal gyrus with increased index length for the delay period. These results show that relational load is not reducible to item load.
Scott, Terry F.; Schumayer, Daniel
In this paper we present a series of item response models of data collected using the Force Concept Inventory. The Force Concept Inventory (FCI) was designed to poll the Newtonian conception of force viewed as a multidimensional concept, that is, as a complex of distinguishable conceptual dimensions. Several previous studies have developed single-trait item response models of FCI data; however, we feel that multidimensional models are also appropriate given the explicitly multidimensional design of the inventory. The models employed in the research reported here vary in both the number of fitting parameters and the number of underlying latent traits assumed. We calculate several model information statistics to ensure adequate model fit and to determine which of the models provides the optimal balance of information and parsimony. Our analysis indicates that all item response models tested, from the single-trait Rasch model through to a model with ten latent traits, satisfy the standard requirements of fit. However, analysis of model information criteria indicates that the five-trait model is optimal. We note that an earlier factor analysis of the same FCI data also led to a five-factor model. Furthermore the factors in our previous study and the traits identified in the current work match each other well. The optimal five-trait model assigns proficiency scores to all respondents for each of the five traits. We construct a correlation matrix between the proficiencies in each of these traits. This correlation matrix shows strong correlations between some proficiencies, and strong anticorrelations between others. We present an interpretation of this correlation matrix.
Erhart, M; Hagquist, C; Auquier, P; Rajmil, L; Power, M; Ravens-Sieberer, U
This study compares item reduction analysis based on classical test theory (maximizing Cronbach's alpha - approach A), with analysis based on the Rasch Partial Credit Model item-fit (approach B), as applied to children and adolescents' health-related quality of life (HRQoL) items. The reliability and structural, cross-cultural and known-group validity of the measures were examined. Within the European KIDSCREEN project, 3019 children and adolescents (8-18 years) from seven European countries answered 19 HRQoL items of the Physical Well-being dimension of a preliminary KIDSCREEN instrument. The Cronbach's alpha and corrected item total correlation (approach A) were compared with infit mean squares and the Q-index item-fit derived according to a partial credit model (approach B). Cross-cultural differential item functioning (DIF ordinal logistic regression approach), structural validity (confirmatory factor analysis and residual correlation) and relative validity (RV) for socio-demographic and health-related factors were calculated for approaches (A) and (B). Approach (A) led to the retention of 13 items, compared with 11 items with approach (B). The item overlap was 69% for (A) and 78% for (B). The correlation coefficient of the summated ratings was 0.93. The Cronbach's alpha was similar for both versions [0.86 (A); 0.85 (B)]. Both approaches selected some items that are not strictly unidimensional and items displaying DIF. RV ratios favoured (A) with regard to socio-demographic aspects. Approach (B) was superior in RV with regard to health-related aspects. Both types of item reduction analysis should be accompanied by additional analyses. Neither of the two approaches was universally superior with regard to cultural, structural and known-group validity. However, the results support the usability of the Rasch method for developing new HRQoL measures for children and adolescents.
Chaudhary, Pankaj; Deshmukh, Aaradhana A.; Mihovska, Albena Dimitrova
Recommendation systems suggest items and users of interest based on preferences of items or users and item or user attributes. In social media-based services of dynamic content (such as news, blog, video, movies, books, etc.), recommender systems face the problem of discovering new items, new users...... the problem of identifying the new items and new users, to alleviate the dimensionality of the item-user rating matrix using biclustering technique. To overcome the information exiguity and rating diversity, it uses the smoothing and fusion technique. As discussed, the system presents content aware multimedia...
Lucien Teunckens; Kurt Pflugrad; Candace Chan-Sands; Ted Lazo
The European Commission (EC), the International Atomic Energy Agency (IAEA), and the Organization for Economic Cooperation and Development/Nuclear Energy Agency (OECD/NEA) have agreed to jointly prepare and publish a standardized list of cost items and related definitions for decommissioning projects. Such a standardized list would facilitate communication, promote uniformity, and avoid inconsistency or contradiction of results or conclusions of cost evaluations for decommissioning projects carried out for specific purposes by different groups. Additionally, a standardized structure would also be a useful tool for more effective cost management. This paper describes actual work and result thus far
Wang Dong; Zhang Quanhu; He Bin; Wang Hua; Yang Daojun
Nuclear material accounting is a key measure for nuclear safeguard. Software for MUF evaluation in item nuclear material accounting was worked out in this paper. It is composed of several models, including input model, data processing model, data inquiring model, data print model, system setting model etc. It could be used to check the variance of the measurement and estimate the confidence interval according to the MUF value. To insure security of the data multi-user management function was applied in the software. (authors)
Varepo, L. G.; Ermakova, I. N.; Nagornova, I. V.; Kondratov, A. P.
The methods of visual and instrumental express diagnostics of safety critical defects and non-uniform thickness of transparent mono- and multilayer polyolefin surface coating of metal items are analyzed in the paper. The instrumental diagnostics method relates to colorimetric measuring based on effects, which appear in the polarized light for extrusion polymer coatings. A color coordinates dependence (in the color system CIE La*b*) on both HDPE / PVC coating thickness fluctuation values (from average ones) and coating interlayer or adhesion layer delaminating is shown. A variation of color characteristics in the polarized light at a liquid penetration into delaminated polymer layers is found. Measuring parameters and critical uncertainties are defined.
Full Text Available This paper summarizes the results of the translation work carried out within an international project aiming to develop the language skills of staff working in hotel and catering services. As the topics touched upon in the English source texts are related to several European cultures, these cultural differences bring about several challenges related to the translation of realia, or culture-specific items (CSIs. In the first part of the paper, a series of translation strategies for rendering source-language CSIs into the target language are enlisted, while the second part presents the main strategies employed in the prepared translations.
Full Text Available A continuous production control inventory model for deteriorating items with shortages is developed. A number of structural properties of the inventory system are studied analytically. The formulae for the optimal average system cost, stock level, backlog level and production cycle time are derived when the deterioration rate is very small. Numerical examples are taken to illustrate the procedure of finding the optimal total inventory cost, stock level, backlog level and production cycle time. Sensitivity analysis is carried out to demonstrate the effects of changing parameter values on the optimal solution of the system.
Hamane, Ryoso; Itoh, Toshiya
When a store sells items to customers, the store wishes to decide the prices of the items to maximize its profit. If the store sells the items with low (resp. high) prices, the customers buy more (resp. less) items, which provides less profit to the store. It would be hard for the store to decide the prices of items. Assume that a store has a set V of n items and there is a set C of m customers who wish to buy those items. The goal of the store is to decide the price of each item to maximize its profit. We refer to this maximization problem as an item pricing problem. We classify the item pricing problems according to how many items the store can sell or how the customers valuate the items. If the store can sell every item i with unlimited (resp. limited) amount, we refer to this as unlimited supply (resp. limited supply). We say that the item pricing problem is single-minded if each customer j∈C wishes to buy a set ej⊆V of items and assigns valuation w(ej)≥0. For the single-minded item pricing problems (in unlimited supply), Balcan and Blum regarded them as weighted k-hypergraphs and gave several approximation algorithms. In this paper, we focus on the (pseudo) degree of k-hypergraphs and the valuation ratio, i. e., the ratio between the smallest and the largest valuations. Then for the single-minded item pricing problems (in unlimited supply), we show improved approximation algorithms (for k-hypergraphs, general graphs, bipartite graphs, etc.) with respect to the maximum (pseudo) degree and the valuation ratio.
Weidmer, Beverly A; Brach, Cindy; Hays, Ron D
The complexity of health information often exceeds patients' skills to understand and use it. To develop survey items assessing how well healthcare providers communicate health information. Domains and items for the Consumer Assessment of Healthcare Providers and Systems (CAHPS) Item Set for Addressing Health Literacy were identified through an environmental scan and input from stakeholders. The draft item set was translated into Spanish and pretested in both English and Spanish. The revised item set was field tested with a randomly selected sample of adult patients from 2 sites using mail and telephonic data collection. Item-scale correlations, confirmatory factor analysis, and internal consistency reliability estimates were estimated to assess how well the survey items performed and identify composite measures. Finally, we regressed the CAHPS global rating of the provider item on the CAHPS core communication composite and the new health literacy composites. A total of 601 completed surveys were obtained (52% response rate). Two composite measures were identified: (1) Communication to Improve Health Literacy (16 items); and (2) How Well Providers Communicate About Medicines (6 items). These 2 composites were significantly uniquely associated with the global rating of the provider (communication to improve health literacy: PLiteracy composite accounted for 90% of the variance of the original 16-item composite. This study provides support for reliability and validity of the CAHPS Item Set for Addressing Health Literacy. These items can serve to assess whether healthcare providers have communicated effectively with their patients and as a tool for quality improvement.
In connection with the Three Mile Island nuclear power accident in March, 1979, in the United States, in order to introduce the lessons from it in the nuclear power safety regulations in Japan, 52 items to be reflected to the nuclear power safety measures were chosen by the Nuclear Safety Commission. Of these, 16 items were examined by the Committee on Examination of Reactor Safety. It was decided that these results would be introduced in the nuclear safety regulations, by the Nuclear Safety Commission. The following 16 items are described. For the examination, four items concerning the automatic operation of safety systems and others; for the design, five items concerning a small rupture accident, the monitoring of the state of primary coolant, control room layout and others; for the operation management, seven items concerning the inspection at the time of repair, the prevention of faulty handlings by operators and others.
In connection with the Three Mile Island nuclear power accident in March, 1979, in the United States, in order to introduce the lessons from it in the nuclear power safety regulations in Japan, 52 items to be reflected to the nuclear power safety measures were chosen by the Nuclear Safety Commission. Of these, 16 items were examined by the Committee on Examination of Reactor Safety. It was decided that these results would be introduced in the nuclear safety regulations, by the Nuclear Safety Commission. The following 16 items are described. For the examination, four items concerning the automatic operation of safety systems and others; for the design, five items concerning a small rupture accident, the monitoring of the state of primary coolant, control room layout and others; for the operation management, seven items concerning the inspection at the time of repair, the prevention of faulty handlings by operators and others. (J.P.N.)
Rolls, Edmund T.; Dempere-Marco, Laura; Deco, Gustavo
Human short term memory has a capacity of several items maintained simultaneously. We show how the number of short term memory representations that an attractor network modeling a cortical local network can simultaneously maintain active is increased by using synaptic facilitation of the type found in the prefrontal cortex. We have been able to maintain 9 short term memories active simultaneously in integrate-and-fire simulations where the proportion of neurons in each population, the sparseness, is 0.1, and have confirmed the stability of such a system with mean field analyses. Without synaptic facilitation the system can maintain many fewer memories active in the same network. The system operates because of the effectively increased synaptic strengths formed by the synaptic facilitation just for those pools to which the cue is applied, and then maintenance of this synaptic facilitation in just those pools when the cue is removed by the continuing neuronal firing in those pools. The findings have implications for understanding how several items can be maintained simultaneously in short term memory, how this may be relevant to the implementation of language in the brain, and suggest new approaches to understanding and treating the decline in short term memory that can occur with normal aging. PMID:23613789
Agam, Gady; Gan, Lin; Moric, Mario; Gluncic, Vicko
Retained surgical items (RSIs) in patients is a major operating room (OR) patient safety concern. An RSI is any surgical tool, sponge, needle or other item inadvertently left in a patients body during the course of surgery. If left undetected, RSIs may lead to serious negative health consequences such as sepsis, internal bleeding, and even death. To help physicians efficiently and effectively detect RSIs, we are developing computer-aided detection (CADe) software for X-ray (XR) image analysis, utilizing large amounts of currently available image data to produce a clinically effective RSI detection system. Physician analysis of XRs for the purpose of RSI detection is a relatively lengthy process that may take up to 45 minutes to complete. It is also error prone due to the relatively low acuity of the human eye for RSIs in XR images. The system we are developing is based on computer vision and machine learning algorithms. We address the problem of low incidence by proposing synthesis algorithms. The CADe software we are developing may be integrated into a picture archiving and communication system (PACS), be implemented as a stand-alone software application, or be integrated into portable XR machine software through application programming interfaces. Preliminary experimental results on actual XR images demonstrate the effectiveness of the proposed approach.
Scarf, Damian; Colombo, Michael
Ordinal knowledge is a fundamental aspect of advanced cognition. It is self-evident that humans represent ordinal knowledge, and over the past 20 years it has become clear that nonhuman primates share this ability. In contrast, evidence that nonprimate species represent ordinal knowledge is missing from the comparative literature. To address this issue, in the present experiment we trained pigeons on three 4-item lists and then tested them with derived lists in which, relative to the training lists, the ordinal position of the items was either maintained or changed. Similar to the findings with human and nonhuman primates, our pigeons performed markedly better on the maintained lists compared to the changed lists, and displayed errors consistent with the view that they used their knowledge of ordinal position to guide responding on the derived lists. These findings demonstrate that the ability to acquire ordinal knowledge is not unique to the primate lineage. (PsycINFO Database Record (c) 2011 APA, all rights reserved).
Anspach, D.A.; Waddoups, I.G.; Fox, E.T.
The Department of Energy (DOE) mission is changing due to the number of nuclear weapon reductions by the United States and the former Soviet Union with long-term storage requirements for DOE sites increasing. New technology to ensure the integrity of special nuclear material (SNM) in storage is available to sites to supplement manual physical inventories. This allows them to decrease operating costs while keeping radiation exposure at minimal levels. We have developed a generic, real time, personnel tracking and material monitoring system named PAMTRAK. Such a system can significantly reduce the number of required, manual physical inventories at DOE sites while increasing assurance that an insider has not diverted or stolen material. Until recently Pamtrak used only material monitoring devices that provided location/containment attributes. However, Westinghouse Electric Corp. and Metrox, Inc. have recently developed hard-wired item/material attribute systems that monitor both temperature and weight. We have incorporated both of these systems into PAMTRAK. If a site employed one of these item/material attribute systems, it could decrease its manual inventory frequency to three years. This paper describes how a site might implement such a system to meet the DOE's requirements
Sheriff, Marnelle L.
This procedure implements portions of the requirements of MSC-MP-599, Quality Assurance Program Description. It establishes the Mission Support Alliance (MSA) practices for minimizing the introduction of and identifying, documenting, dispositioning, reporting, controlling, and disposing of suspect/counterfeit and defective items (S/CIs). employees whose work scope relates to Safety Systems (i.e., Safety Class [SC] or Safety Significant [SS] items), non-safety systems and other applications (i.e., General Service [GS]) where engineering has determined that their use could result in a potential safety hazard. MSA implements an effective Quality Assurance (QA) Program providing a comprehensive network of controls and verification providing defense-in-depth by preventing the introduction of S/CIs through the design, procurement, construction, operation, maintenance, and modification of processes. This procedure focuses on those safety systems, and other systems, including critical load paths of lifting equipment, where the introduction of S/CIs would have the greatest potential for creating unsafe conditions.
Goldfarb, S [CERN-PH, 1211 Geneva 23 (Switzerland); Herr, J; Neal, H A [Assistant Research Scientist, University of Michigan (United States); Research Process Manager, University of Michigan (United States); Professor of Physics, University of Michigan (United States)], E-mail: firstname.lastname@example.org
Shaping Collaboration 2006  was a workshop held in Geneva, on December 11-13, 2006, to examine the status and future of collaborative tool technology and its usage for large global scientific collaborations, such as those of the CERN LHC . The workshop brought together some of the leading experts in the field of collaborative tools (WACE 2006)  with physicists and developers of the LHC collaborations and HENP (High-Energy and Nuclear Physics). We highlight important presentations and key discussions held during the workshop, then focus on a large and aggressive set of goals and specific action items targeted at institutes from all levels of the LHC organization. This list of action items, assembled during a panel discussion at the close of the LHC sessions, includes recommendations for the LHC Users, their Universities, Project Managers, Spokespersons, National Funding Agencies and Host Laboratories. We present this list, along with suggestions for priorities in addressing the immediate and long-term needs of HENP.
Goldfarb, S; Herr, J; Neal, H A
Shaping Collaboration 2006  was a workshop held in Geneva, on December 11-13, 2006, to examine the status and future of collaborative tool technology and its usage for large global scientific collaborations, such as those of the CERN LHC . The workshop brought together some of the leading experts in the field of collaborative tools (WACE 2006)  with physicists and developers of the LHC collaborations and HENP (High-Energy and Nuclear Physics). We highlight important presentations and key discussions held during the workshop, then focus on a large and aggressive set of goals and specific action items targeted at institutes from all levels of the LHC organization. This list of action items, assembled during a panel discussion at the close of the LHC sessions, includes recommendations for the LHC Users, their Universities, Project Managers, Spokespersons, National Funding Agencies and Host Laboratories. We present this list, along with suggestions for priorities in addressing the immediate and long-term needs of HENP
French, Simone A; Wall, Melanie; Mitchell, Nathan R
The present study examined income-related household food purchases among a sample of 90 households from the community. Annotated food purchase receipts were collected for a four-week period by the primary household shopper. Receipt food source and foods items were classified into specific categories, and food quantities in ounces were recorded by research staff. For home sources, a limited number of food/beverage categories were recorded. For eating out sources, all food/beverage items were recorded. Median monthly per person dollars spent and per person ounces purchased were computed. Food sources and food categories were examined by household income tertile. A community-based sample of 90 households. Higher income households spent significantly more dollars per person per month from both home and eating out sources compared with lower income households ($163 versus $100, p income households, higher income households spent significantly more home source dollars on both fruits/vegetables (21.5 versus 10.2, p income households (45% versus 26%, p sources, lower income households spent a significantly greater percent of dollars per person at carry out places (54% versus 37%, p income differences were observed for dollars spent at discount grocery stores, small grocery stores or convenience stores. Higher income households spent more money on both healthy and less healthy foods from a wide range of sources. Lower income households spent a larger proportion of their eating out dollars at carry out places, and a larger proportion of their home beverage purchases were sugar sweetened beverages.
Edmund T Rolls
Full Text Available Human short term memory has a capacity of several items maintained simultaneously. We show how the number of short term memory representations that an attractor network modeling a cortical local network can simultaneously maintain active is increased by using synaptic facilitation of the type found in the prefrontal cortex. We have been able to maintain 9 short term memories active simultaneously in integrate-and-fire simulations where the proportion of neurons in each population, the sparseness, is 0.1, and have confirmed the stability of such a system with mean field analyses. Without synaptic facilitation the system can maintain many fewer memories active in the same network. The system operates because of the effectively increased synaptic strengths formed by the synaptic facilitation just for those pools to which the cue is applied, and then maintenance of this synaptic facilitation in just those pools when the cue is removed by the continuing neuronal firing in those pools. The findings have implications for understanding how several items can be maintained simultaneously in short term memory, how this may be relevant to the implementation of language in the brain, and suggest new approaches to understanding and treating the decline in short term memory that can occur with normal aging.
Rolls, Edmund T; Dempere-Marco, Laura; Deco, Gustavo
Human short term memory has a capacity of several items maintained simultaneously. We show how the number of short term memory representations that an attractor network modeling a cortical local network can simultaneously maintain active is increased by using synaptic facilitation of the type found in the prefrontal cortex. We have been able to maintain 9 short term memories active simultaneously in integrate-and-fire simulations where the proportion of neurons in each population, the sparseness, is 0.1, and have confirmed the stability of such a system with mean field analyses. Without synaptic facilitation the system can maintain many fewer memories active in the same network. The system operates because of the effectively increased synaptic strengths formed by the synaptic facilitation just for those pools to which the cue is applied, and then maintenance of this synaptic facilitation in just those pools when the cue is removed by the continuing neuronal firing in those pools. The findings have implications for understanding how several items can be maintained simultaneously in short term memory, how this may be relevant to the implementation of language in the brain, and suggest new approaches to understanding and treating the decline in short term memory that can occur with normal aging.
Bingenheimer, Jeffrey B; Raudenbush, Stephen W; Leventhal, Tama; Brooks-Gunn, Jeanne
Several hypotheses in family psychology involve comparisons of sociocultural groups. Yet the potential for cross-cultural inequivalence in widely used psychological measurement instruments threatens the validity of inferences about group differences. Methods for dealing with these issues have been developed via the framework of item response theory. These methods deal with an important type of measurement inequivalence, called differential item functioning (DIF). The authors introduce DIF analytic methods, linking them to a well-established framework for conceptualizing cross-cultural measurement equivalence in psychology (C.H. Hui and H.C. Triandis, 1985). They illustrate the use of DIF methods using data from the Project on Human Development in Chicago Neighborhoods (PHDCN). Focusing on the Caregiver Warmth and Environmental Organization scales from the PHDCN's adaptation of the Home Observation for Measurement of the Environment Inventory, the authors obtain results that exemplify the range of outcomes that may result when these methods are applied to psychological measurement instruments. (c) 2005 APA, all rights reserved
LeBouthillier, Daniel M; Thibodeau, Michel A; Alberts, Nicole M; Hadjistavropoulos, Heather D; Asmundson, Gordon J G
Individuals with medical conditions are likely to have elevated health anxiety; however, research has not demonstrated how medical status impacts response patterns on health anxiety measures. Measurement bias can undermine the validity of a questionnaire by overestimating or underestimating scores in groups of individuals. We investigated whether the Short Health Anxiety Inventory (SHAI), a widely-used measure of health anxiety, exhibits medical condition-based bias on item and subscale levels, and whether the SHAI subscales adequately assess the health anxiety continuum. Data were from 963 individuals with diabetes, breast cancer, or multiple sclerosis, and 372 healthy individuals. Mantel-Haenszel tests and item characteristic curves were used to classify the severity of item-level differential item functioning in all three medical groups compared to the healthy group. Test characteristic curves were used to assess scale-level differential item functioning and whether the SHAI subscales adequately assess the health anxiety continuum. Nine out of 14 items exhibited differential item functioning. Two items exhibited differential item functioning in all medical groups compared to the healthy group. In both Thought Intrusion and Fear of Illness subscales, differential item functioning was associated with mildly deflated scores in medical groups with very high levels of the latent traits. Fear of Illness items poorly discriminated between individuals with low and very low levels of the latent trait. While individuals with medical conditions may respond differentially to some items, clinicians and researchers can confidently use the SHAI with a variety of medical populations without concern of significant bias. Copyright © 2015 Elsevier Inc. All rights reserved.
Knol Dirk L
Full Text Available Abstract Background For the Low Vision Quality Of Life questionnaire (LVQOL it is unknown whether the psychometric properties are satisfactory when an item response theory (IRT perspective is considered. This study evaluates some essential psychometric properties of the LVQOL questionnaire in an IRT model, and investigates differential item functioning (DIF. Methods Cross-sectional data were used from an observational study among visually-impaired patients (n = 296. Calibration was performed for every dimension of the LVQOL in the graded response model. Item goodness-of-fit was assessed with the S-X2-test. DIF was assessed on relevant background variables (i.e. age, gender, visual acuity, eye condition, rehabilitation type and administration type with likelihood-ratio tests for DIF. The magnitude of DIF was interpreted by assessing the largest difference in expected scores between subgroups. Measurement precision was assessed by presenting test information curves; reliability with the index of subject separation. Results All items of the LVQOL dimensions fitted the model. There was significant DIF on several items. For two items the maximum difference between expected scores exceeded one point, and DIF was found on multiple relevant background variables. Item 1 'Vision in general' from the "Adjustment" dimension and item 24 'Using tools' from the "Reading and fine work" dimension were removed. Test information was highest for the "Reading and fine work" dimension. Indices for subject separation ranged from 0.83 to 0.94. Conclusions The items of the LVQOL showed satisfactory item fit to the graded response model; however, two items were removed because of DIF. The adapted LVQOL with 21 items is DIF-free and therefore seems highly appropriate for use in heterogeneous populations of visually impaired patients.
Susan C. Gillmor
Full Text Available This study explores a new item-writing framework for improving the validity of math assessment items. The authors transfer insights from Cognitive Load Theory (CLT, traditionally used in instructional design, to educational measurement. Fifteen, multiple-choice math assessment items were modified using research-based strategies for reducing extraneous cognitive load. An experimental design with 222 middle-school students tested the effects of the reduced cognitive load items on student performance and anxiety. Significant findings confirm the main research hypothesis that reducing the cognitive load of math assessment items improves student performance. Three load-reducing item modifications are identified as particularly effective for reducing item difficulty: signalling important information, aesthetic item organization, and removing extraneous content. Load reduction was not shown to impact student anxiety. Implications for classroom assessment and future research are discussed.
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