WorldWideScience

Sample records for series estimating teacher

  1. The Prediction of Teacher Turnover Employing Time Series Analysis.

    Science.gov (United States)

    Costa, Crist H.

    The purpose of this study was to combine knowledge of teacher demographic data with time-series forecasting methods to predict teacher turnover. Moving averages and exponential smoothing were used to forecast discrete time series. The study used data collected from the 22 largest school districts in Iowa, designated as FACT schools. Predictions…

  2. Global Population Density Grid Time Series Estimates

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Population Density Grid Time Series Estimates provide a back-cast time series of population density grids based on the year 2000 population grid from SEDAC's...

  3. "In the Footsteps of Alexander the Great" PBS Series. Teacher's Guide.

    Science.gov (United States)

    Corporation for Public Broadcasting, Washington, DC.

    This teacher's guide correlates with the Public Broadcasting Service (PBS) television series "In the Footsteps of Alexander the Great" hosted by historian Michael Wood. The four episodes of the series are entitled: "Son of God"; "Lord of Asia"; "Across the Hindu Kush"; and "To the Ends of the…

  4. Similarity estimators for irregular and age uncertain time series

    Science.gov (United States)

    Rehfeld, K.; Kurths, J.

    2013-09-01

    Paleoclimate time series are often irregularly sampled and age uncertain, which is an important technical challenge to overcome for successful reconstruction of past climate variability and dynamics. Visual comparison and interpolation-based linear correlation approaches have been used to infer dependencies from such proxy time series. While the first is subjective, not measurable and not suitable for the comparison of many datasets at a time, the latter introduces interpolation bias, and both face difficulties if the underlying dependencies are nonlinear. In this paper we investigate similarity estimators that could be suitable for the quantitative investigation of dependencies in irregular and age uncertain time series. We compare the Gaussian-kernel based cross correlation (gXCF, Rehfeld et al., 2011) and mutual information (gMI, Rehfeld et al., 2013) against their interpolation-based counterparts and the new event synchronization function (ESF). We test the efficiency of the methods in estimating coupling strength and coupling lag numerically, using ensembles of synthetic stalagmites with short, autocorrelated, linear and nonlinearly coupled proxy time series, and in the application to real stalagmite time series. In the linear test case coupling strength increases are identified consistently for all estimators, while in the nonlinear test case the correlation-based approaches fail. The lag at which the time series are coupled is identified correctly as the maximum of the similarity functions in around 60-55% (in the linear case) to 53-42% (for the nonlinear processes) of the cases when the dating of the synthetic stalagmite is perfectly precise. If the age uncertainty increases beyond 5% of the time series length, however, the true coupling lag is not identified more often than the others for which the similarity function was estimated. Age uncertainty contributes up to half of the uncertainty in the similarity estimation process. Time series irregularity

  5. Similarity estimators for irregular and age-uncertain time series

    Science.gov (United States)

    Rehfeld, K.; Kurths, J.

    2014-01-01

    Paleoclimate time series are often irregularly sampled and age uncertain, which is an important technical challenge to overcome for successful reconstruction of past climate variability and dynamics. Visual comparison and interpolation-based linear correlation approaches have been used to infer dependencies from such proxy time series. While the first is subjective, not measurable and not suitable for the comparison of many data sets at a time, the latter introduces interpolation bias, and both face difficulties if the underlying dependencies are nonlinear. In this paper we investigate similarity estimators that could be suitable for the quantitative investigation of dependencies in irregular and age-uncertain time series. We compare the Gaussian-kernel-based cross-correlation (gXCF, Rehfeld et al., 2011) and mutual information (gMI, Rehfeld et al., 2013) against their interpolation-based counterparts and the new event synchronization function (ESF). We test the efficiency of the methods in estimating coupling strength and coupling lag numerically, using ensembles of synthetic stalagmites with short, autocorrelated, linear and nonlinearly coupled proxy time series, and in the application to real stalagmite time series. In the linear test case, coupling strength increases are identified consistently for all estimators, while in the nonlinear test case the correlation-based approaches fail. The lag at which the time series are coupled is identified correctly as the maximum of the similarity functions in around 60-55% (in the linear case) to 53-42% (for the nonlinear processes) of the cases when the dating of the synthetic stalagmite is perfectly precise. If the age uncertainty increases beyond 5% of the time series length, however, the true coupling lag is not identified more often than the others for which the similarity function was estimated. Age uncertainty contributes up to half of the uncertainty in the similarity estimation process. Time series irregularity

  6. Efficient multidimensional regularization for Volterra series estimation

    Science.gov (United States)

    Birpoutsoukis, Georgios; Csurcsia, Péter Zoltán; Schoukens, Johan

    2018-05-01

    This paper presents an efficient nonparametric time domain nonlinear system identification method. It is shown how truncated Volterra series models can be efficiently estimated without the need of long, transient-free measurements. The method is a novel extension of the regularization methods that have been developed for impulse response estimates of linear time invariant systems. To avoid the excessive memory needs in case of long measurements or large number of estimated parameters, a practical gradient-based estimation method is also provided, leading to the same numerical results as the proposed Volterra estimation method. Moreover, the transient effects in the simulated output are removed by a special regularization method based on the novel ideas of transient removal for Linear Time-Varying (LTV) systems. Combining the proposed methodologies, the nonparametric Volterra models of the cascaded water tanks benchmark are presented in this paper. The results for different scenarios varying from a simple Finite Impulse Response (FIR) model to a 3rd degree Volterra series with and without transient removal are compared and studied. It is clear that the obtained models capture the system dynamics when tested on a validation dataset, and their performance is comparable with the white-box (physical) models.

  7. Learning of time series through neuron-to-neuron instruction

    Energy Technology Data Exchange (ETDEWEB)

    Miyazaki, Y [Department of Physics, Kyoto University, Kyoto 606-8502, (Japan); Kinzel, W [Institut fuer Theoretische Physik, Universitaet Wurzburg, 97074 Wurzburg (Germany); Shinomoto, S [Department of Physics, Kyoto University, Kyoto (Japan)

    2003-02-07

    A model neuron with delayline feedback connections can learn a time series generated by another model neuron. It has been known that some student neurons that have completed such learning under the instruction of a teacher's quasi-periodic sequence mimic the teacher's time series over a long interval, even after instruction has ceased. We found that in addition to such faithful students, there are unfaithful students whose time series eventually diverge exponentially from that of the teacher. In order to understand the circumstances that allow for such a variety of students, the orbit dimension was estimated numerically. The quasi-periodic orbits in question were found to be confined in spaces with dimensions significantly smaller than that of the full phase space.

  8. Learning of time series through neuron-to-neuron instruction

    International Nuclear Information System (INIS)

    Miyazaki, Y; Kinzel, W; Shinomoto, S

    2003-01-01

    A model neuron with delayline feedback connections can learn a time series generated by another model neuron. It has been known that some student neurons that have completed such learning under the instruction of a teacher's quasi-periodic sequence mimic the teacher's time series over a long interval, even after instruction has ceased. We found that in addition to such faithful students, there are unfaithful students whose time series eventually diverge exponentially from that of the teacher. In order to understand the circumstances that allow for such a variety of students, the orbit dimension was estimated numerically. The quasi-periodic orbits in question were found to be confined in spaces with dimensions significantly smaller than that of the full phase space

  9. On a family of Bessel type functions: Estimations, series, overconvergence

    Science.gov (United States)

    Paneva-Konovska, Jordanka

    2017-12-01

    A family of the Bessel-Maitland functions are considered in this paper and some useful estimations are obtained for them. Series defined by means of these functions are considered and their behaviour on the boundaries of the convergence domains is discussed. Using the obtained estimations, necessary and sufficient conditions for the series overconvergence, as well as Hadamard type theorem are proposed.

  10. Invasion Ecology. Teacher's Guide [and Student Edition]. Cornell Scientific Inquiry Series.

    Science.gov (United States)

    Krasny, Marianne E.; Trautmann, Nancy; Carlsen, William; Cunningham, Christine

    This book contains the teacher's guide of the Environmental Inquiry curriculum series developed at Cornell University. It is designed to teach learning skills for investigating the behaviors of non-native and native species and demonstrate how to apply scientific knowledge to solve real-life problems. This book focuses on strange intruders…

  11. Estimating the level of dynamical noise in time series by using fractal dimensions

    Energy Technology Data Exchange (ETDEWEB)

    Sase, Takumi, E-mail: sase@sat.t.u-tokyo.ac.jp [Graduate School of Information Science and Technology, The University of Tokyo, Tokyo 153-8505 (Japan); Ramírez, Jonatán Peña [CONACYT Research Fellow, Center for Scientific Research and Higher Education at Ensenada (CICESE), Carretera Ensenada-Tijuana No. 3918, Zona Playitas, C.P. 22860, Ensenada, Baja California (Mexico); Kitajo, Keiichi [BSI-Toyota Collaboration Center, RIKEN Brain Science Institute, Wako, Saitama 351-0198 (Japan); Aihara, Kazuyuki; Hirata, Yoshito [Graduate School of Information Science and Technology, The University of Tokyo, Tokyo 153-8505 (Japan); Institute of Industrial Science, The University of Tokyo, Tokyo 153-8505 (Japan)

    2016-03-11

    We present a method for estimating the dynamical noise level of a ‘short’ time series even if the dynamical system is unknown. The proposed method estimates the level of dynamical noise by calculating the fractal dimensions of the time series. Additionally, the method is applied to EEG data to demonstrate its possible effectiveness as an indicator of temporal changes in the level of dynamical noise. - Highlights: • A dynamical noise level estimator for time series is proposed. • The estimator does not need any information about the dynamics generating the time series. • The estimator is based on a novel definition of time series dimension (TSD). • It is demonstrated that there exists a monotonic relationship between the • TSD and the level of dynamical noise. • We apply the proposed method to human electroencephalographic data.

  12. Estimating the level of dynamical noise in time series by using fractal dimensions

    International Nuclear Information System (INIS)

    Sase, Takumi; Ramírez, Jonatán Peña; Kitajo, Keiichi; Aihara, Kazuyuki; Hirata, Yoshito

    2016-01-01

    We present a method for estimating the dynamical noise level of a ‘short’ time series even if the dynamical system is unknown. The proposed method estimates the level of dynamical noise by calculating the fractal dimensions of the time series. Additionally, the method is applied to EEG data to demonstrate its possible effectiveness as an indicator of temporal changes in the level of dynamical noise. - Highlights: • A dynamical noise level estimator for time series is proposed. • The estimator does not need any information about the dynamics generating the time series. • The estimator is based on a novel definition of time series dimension (TSD). • It is demonstrated that there exists a monotonic relationship between the • TSD and the level of dynamical noise. • We apply the proposed method to human electroencephalographic data.

  13. Estimation of pure autoregressive vector models for revenue series ...

    African Journals Online (AJOL)

    This paper aims at applying multivariate approach to Box and Jenkins univariate time series modeling to three vector series. General Autoregressive Vector Models with time varying coefficients are estimated. The first vector is a response vector, while others are predictor vectors. By matrix expansion each vector, whether ...

  14. Time Series Decomposition into Oscillation Components and Phase Estimation.

    Science.gov (United States)

    Matsuda, Takeru; Komaki, Fumiyasu

    2017-02-01

    Many time series are naturally considered as a superposition of several oscillation components. For example, electroencephalogram (EEG) time series include oscillation components such as alpha, beta, and gamma. We propose a method for decomposing time series into such oscillation components using state-space models. Based on the concept of random frequency modulation, gaussian linear state-space models for oscillation components are developed. In this model, the frequency of an oscillator fluctuates by noise. Time series decomposition is accomplished by this model like the Bayesian seasonal adjustment method. Since the model parameters are estimated from data by the empirical Bayes' method, the amplitudes and the frequencies of oscillation components are determined in a data-driven manner. Also, the appropriate number of oscillation components is determined with the Akaike information criterion (AIC). In this way, the proposed method provides a natural decomposition of the given time series into oscillation components. In neuroscience, the phase of neural time series plays an important role in neural information processing. The proposed method can be used to estimate the phase of each oscillation component and has several advantages over a conventional method based on the Hilbert transform. Thus, the proposed method enables an investigation of the phase dynamics of time series. Numerical results show that the proposed method succeeds in extracting intermittent oscillations like ripples and detecting the phase reset phenomena. We apply the proposed method to real data from various fields such as astronomy, ecology, tidology, and neuroscience.

  15. ACER Tests of Basic Skills: Aspects of Literacy, Aspects of Numercy. Teacher's Manual. Blue Series 6.

    Science.gov (United States)

    Lokan, Jan; And Others

    Developed for the Basic Skills Testing Program (BSTP) in New South Wales, Australia, this teacher's manual describes the ACER (Australian Council for Educational Research) Tests of Basic Skills. The two tests in this series, Aspects of Literacy and Aspects of Numeracy, were administered statewide by government school classroom teachers in August,…

  16. Computational Error Estimate for the Power Series Solution of Odes ...

    African Journals Online (AJOL)

    This paper compares the error estimation of power series solution with recursive Tau method for solving ordinary differential equations. From the computational viewpoint, the power series using zeros of Chebyshevpolunomial is effective, accurate and easy to use. Keywords: Lanczos Tau method, Chebyshev polynomial, ...

  17. ESTIMATING RELIABILITY OF DISTURBANCES IN SATELLITE TIME SERIES DATA BASED ON STATISTICAL ANALYSIS

    Directory of Open Access Journals (Sweden)

    Z.-G. Zhou

    2016-06-01

    Full Text Available Normally, the status of land cover is inherently dynamic and changing continuously on temporal scale. However, disturbances or abnormal changes of land cover — caused by such as forest fire, flood, deforestation, and plant diseases — occur worldwide at unknown times and locations. Timely detection and characterization of these disturbances is of importance for land cover monitoring. Recently, many time-series-analysis methods have been developed for near real-time or online disturbance detection, using satellite image time series. However, the detection results were only labelled with “Change/ No change” by most of the present methods, while few methods focus on estimating reliability (or confidence level of the detected disturbances in image time series. To this end, this paper propose a statistical analysis method for estimating reliability of disturbances in new available remote sensing image time series, through analysis of full temporal information laid in time series data. The method consists of three main steps. (1 Segmenting and modelling of historical time series data based on Breaks for Additive Seasonal and Trend (BFAST. (2 Forecasting and detecting disturbances in new time series data. (3 Estimating reliability of each detected disturbance using statistical analysis based on Confidence Interval (CI and Confidence Levels (CL. The method was validated by estimating reliability of disturbance regions caused by a recent severe flooding occurred around the border of Russia and China. Results demonstrated that the method can estimate reliability of disturbances detected in satellite image with estimation error less than 5% and overall accuracy up to 90%.

  18. ACER Tests of Basic Skills: Aspects of Literacy, Aspects of Numeracy. Teacher's Manual. Green Series 6.

    Science.gov (United States)

    Lokan, Jan; And Others

    Developed for the Basic Skills Testing Program (BSTP) in New South Wales, Australia, this teacher's manual describes the Green Series 6 of the ACER (Australian Council for Educational Research) Tests of Basic Skills. The two tests in this series, Aspects of Literacy and Aspects of Numeracy, were administered statewide by government school…

  19. ACER Tests of Basic Skills: Aspects of Literacy, Aspects of Numeracy. Teacher's Manual. Blue Series 3.

    Science.gov (United States)

    Lokan, Jan; And Others

    Developed for the Basic Skills Testing Program (BSTP) in New South Wales, Australia, this teacher's manual describes the Blue Series 3 of the ACER (Australian Council for Educational Research) Tests of Basic Skills. The two tests in the series, Aspects of Literacy and Aspects of Numeracy, were administered statewide by government school classroom…

  20. ACER Tests of Basic Skills: Aspects of Literacy, Aspects of Numeracy. Teacher's Manual. Green Series 3.

    Science.gov (United States)

    Lokan, Jan; And Others

    Developed for the Basic Skills Testing Program (BSTP) in New South Wales, Australia, this teacher's manual describes the Green Series 3 of the ACER (Australian Council for Educational Research) Tests of Basic Skills. The two tests in this series, Aspects of Literacy and Aspects of Numeracy, were administered statewide by government school…

  1. Employ Simulation Techniques. Second Edition. Module C-5 of Category C--Instructional Execution. Professional Teacher Education Module Series.

    Science.gov (United States)

    Ohio State Univ., Columbus. National Center for Research in Vocational Education.

    One of a series of performance-based teacher education learning packages focusing upon specific professional competencies of vocational teachers, this learning module deals with employing simulation techniques. It consists of an introduction and four learning experiences. Covered in the first learning experience are various types of simulation…

  2. Preparation of Teachers of Students with Emotional/Behavioral Disorders. Retrospective Series on Critical Issues in Emotional/Behavioral Disorders.

    Science.gov (United States)

    Bullock, Lyndal M., Ed.; Gable, Robert A., Ed.; Rutherford, Robert B., Jr., Ed.

    The third in a series, this collection of previously published monographs examines the challenges of preparing teachers to work with students who have emotional and behavioral disorders (EBD). Monographs include: (1) "Issues in Training Teachers for the Seriously Emotionally Disturbed" (Frank H. Wood), which discusses preparing regular and special…

  3. Estimation of dynamic flux profiles from metabolic time series data

    Directory of Open Access Journals (Sweden)

    Chou I-Chun

    2012-07-01

    Full Text Available Abstract Background Advances in modern high-throughput techniques of molecular biology have enabled top-down approaches for the estimation of parameter values in metabolic systems, based on time series data. Special among them is the recent method of dynamic flux estimation (DFE, which uses such data not only for parameter estimation but also for the identification of functional forms of the processes governing a metabolic system. DFE furthermore provides diagnostic tools for the evaluation of model validity and of the quality of a model fit beyond residual errors. Unfortunately, DFE works only when the data are more or less complete and the system contains as many independent fluxes as metabolites. These drawbacks may be ameliorated with other types of estimation and information. However, such supplementations incur their own limitations. In particular, assumptions must be made regarding the functional forms of some processes and detailed kinetic information must be available, in addition to the time series data. Results The authors propose here a systematic approach that supplements DFE and overcomes some of its shortcomings. Like DFE, the approach is model-free and requires only minimal assumptions. If sufficient time series data are available, the approach allows the determination of a subset of fluxes that enables the subsequent applicability of DFE to the rest of the flux system. The authors demonstrate the procedure with three artificial pathway systems exhibiting distinct characteristics and with actual data of the trehalose pathway in Saccharomyces cerevisiae. Conclusions The results demonstrate that the proposed method successfully complements DFE under various situations and without a priori assumptions regarding the model representation. The proposed method also permits an examination of whether at all, to what degree, or within what range the available time series data can be validly represented in a particular functional format of

  4. A Modularized Efficient Framework for Non-Markov Time Series Estimation

    Science.gov (United States)

    Schamberg, Gabriel; Ba, Demba; Coleman, Todd P.

    2018-06-01

    We present a compartmentalized approach to finding the maximum a-posteriori (MAP) estimate of a latent time series that obeys a dynamic stochastic model and is observed through noisy measurements. We specifically consider modern signal processing problems with non-Markov signal dynamics (e.g. group sparsity) and/or non-Gaussian measurement models (e.g. point process observation models used in neuroscience). Through the use of auxiliary variables in the MAP estimation problem, we show that a consensus formulation of the alternating direction method of multipliers (ADMM) enables iteratively computing separate estimates based on the likelihood and prior and subsequently "averaging" them in an appropriate sense using a Kalman smoother. As such, this can be applied to a broad class of problem settings and only requires modular adjustments when interchanging various aspects of the statistical model. Under broad log-concavity assumptions, we show that the separate estimation problems are convex optimization problems and that the iterative algorithm converges to the MAP estimate. As such, this framework can capture non-Markov latent time series models and non-Gaussian measurement models. We provide example applications involving (i) group-sparsity priors, within the context of electrophysiologic specrotemporal estimation, and (ii) non-Gaussian measurement models, within the context of dynamic analyses of learning with neural spiking and behavioral observations.

  5. Assess Student Performance: Skills. Second Edition. Module D-4 of Category D--Instructional Evaluation. Professional Teacher Education Module Series.

    Science.gov (United States)

    Ohio State Univ., Columbus. National Center for Research in Vocational Education.

    This module, one of a series of 127 performance-based teacher education learning packages focusing upon specific professional competencies of vocational education teachers, deals with assessing student performance of psychomotor skills. Included in the module are learning experiences that address the following topics: important considerations…

  6. Evaluating Annual Maximum and Partial Duration Series for Estimating Frequency of Small Magnitude Floods

    Directory of Open Access Journals (Sweden)

    Fazlul Karim

    2017-06-01

    Full Text Available Understanding the nature of frequent floods is important for characterising channel morphology, riparian and aquatic habitat, and informing river restoration efforts. This paper presents results from an analysis on frequency estimates of low magnitude floods using the annual maximum and partial series data compared to actual flood series. Five frequency distribution models were fitted to data from 24 gauging stations in the Great Barrier Reef (GBR lagoon catchments in north-eastern Australia. Based on the goodness of fit test, Generalised Extreme Value, Generalised Pareto and Log Pearson Type 3 models were used to estimate flood frequencies across the study region. Results suggest frequency estimates based on a partial series are better, compared to an annual series, for small to medium floods, while both methods produce similar results for large floods. Although both methods converge at a higher recurrence interval, the convergence recurrence interval varies between catchments. Results also suggest frequency estimates vary slightly between two or more partial series, depending on flood threshold, and the differences are large for the catchments that experience less frequent floods. While a partial series produces better frequency estimates, it can underestimate or overestimate the frequency if the flood threshold differs largely compared to bankfull discharge. These results have significant implications in calculating the dependency of floodplain ecosystems on the frequency of flooding and their subsequent management.

  7. Nonparametric autocovariance estimation from censored time series by Gaussian imputation.

    Science.gov (United States)

    Park, Jung Wook; Genton, Marc G; Ghosh, Sujit K

    2009-02-01

    One of the most frequently used methods to model the autocovariance function of a second-order stationary time series is to use the parametric framework of autoregressive and moving average models developed by Box and Jenkins. However, such parametric models, though very flexible, may not always be adequate to model autocovariance functions with sharp changes. Furthermore, if the data do not follow the parametric model and are censored at a certain value, the estimation results may not be reliable. We develop a Gaussian imputation method to estimate an autocovariance structure via nonparametric estimation of the autocovariance function in order to address both censoring and incorrect model specification. We demonstrate the effectiveness of the technique in terms of bias and efficiency with simulations under various rates of censoring and underlying models. We describe its application to a time series of silicon concentrations in the Arctic.

  8. Water temperature forecasting and estimation using fourier series and communication theory techniques

    International Nuclear Information System (INIS)

    Long, L.L.

    1976-01-01

    Fourier series and statistical communication theory techniques are utilized in the estimation of river water temperature increases caused by external thermal inputs. An example estimate assuming a constant thermal input is demonstrated. A regression fit of the Fourier series approximation of temperature is then used to forecast daily average water temperatures. Also, a 60-day prediction of daily average water temperature is made with the aid of the Fourier regression fit by using significant Fourier components

  9. Tightness of M-estimators for multiple linear regression in time series

    DEFF Research Database (Denmark)

    Johansen, Søren; Nielsen, Bent

    We show tightness of a general M-estimator for multiple linear regression in time series. The positive criterion function for the M-estimator is assumed lower semi-continuous and sufficiently large for large argument: Particular cases are the Huber-skip and quantile regression. Tightness requires...

  10. Spectral Estimation of UV-Vis Absorbance Time Series for Water Quality Monitoring

    Directory of Open Access Journals (Sweden)

    Leonardo Plazas-Nossa

    2017-05-01

    Full Text Available Context: Signals recorded as multivariate time series by UV-Vis absorbance captors installed in urban sewer systems, can be non-stationary, yielding complications in the analysis of water quality monitoring. This work proposes to perform spectral estimation using the Box-Cox transformation and differentiation in order to obtain stationary multivariate time series in a wide sense. Additionally, Principal Component Analysis (PCA is applied to reduce their dimensionality. Method: Three different UV-Vis absorbance time series for different Colombian locations were studied: (i El-Salitre Wastewater Treatment Plant (WWTP in Bogotá; (ii Gibraltar Pumping Station (GPS in Bogotá; and (iii San-Fernando WWTP in Itagüí. Each UV-Vis absorbance time series had equal sample number (5705. The esti-mation of the spectral power density is obtained using the average of modified periodograms with rectangular window and an overlap of 50%, with the 20 most important harmonics from the Discrete Fourier Transform (DFT and Inverse Fast Fourier Transform (IFFT. Results: Absorbance time series dimensionality reduction using PCA, resulted in 6, 8 and 7 principal components for each study site respectively, altogether explaining more than 97% of their variability. Values of differences below 30% for the UV range were obtained for the three study sites, while for the visible range the maximum differences obtained were: (i 35% for El-Salitre WWTP; (ii 61% for GPS; and (iii 75% for San-Fernando WWTP. Conclusions: The Box-Cox transformation and the differentiation process applied to the UV-Vis absorbance time series for the study sites (El-Salitre, GPS and San-Fernando, allowed to reduce variance and to eliminate ten-dency of the time series. A pre-processing of UV-Vis absorbance time series is recommended to detect and remove outliers and then apply the proposed process for spectral estimation. Language: Spanish.

  11. Multifractals embedded in short time series: An unbiased estimation of probability moment

    Science.gov (United States)

    Qiu, Lu; Yang, Tianguang; Yin, Yanhua; Gu, Changgui; Yang, Huijie

    2016-12-01

    An exact estimation of probability moments is the base for several essential concepts, such as the multifractals, the Tsallis entropy, and the transfer entropy. By means of approximation theory we propose a new method called factorial-moment-based estimation of probability moments. Theoretical prediction and computational results show that it can provide us an unbiased estimation of the probability moments of continuous order. Calculations on probability redistribution model verify that it can extract exactly multifractal behaviors from several hundred recordings. Its powerfulness in monitoring evolution of scaling behaviors is exemplified by two empirical cases, i.e., the gait time series for fast, normal, and slow trials of a healthy volunteer, and the closing price series for Shanghai stock market. By using short time series with several hundred lengths, a comparison with the well-established tools displays significant advantages of its performance over the other methods. The factorial-moment-based estimation can evaluate correctly the scaling behaviors in a scale range about three generations wider than the multifractal detrended fluctuation analysis and the basic estimation. The estimation of partition function given by the wavelet transform modulus maxima has unacceptable fluctuations. Besides the scaling invariance focused in the present paper, the proposed factorial moment of continuous order can find its various uses, such as finding nonextensive behaviors of a complex system and reconstructing the causality relationship network between elements of a complex system.

  12. Estimation of time-delayed mutual information and bias for irregularly and sparsely sampled time-series

    International Nuclear Information System (INIS)

    Albers, D.J.; Hripcsak, George

    2012-01-01

    Highlights: ► Time-delayed mutual information for irregularly sampled time-series. ► Estimation bias for the time-delayed mutual information calculation. ► Fast, simple, PDF estimator independent, time-delayed mutual information bias estimate. ► Quantification of data-set-size limits of the time-delayed mutual calculation. - Abstract: A method to estimate the time-dependent correlation via an empirical bias estimate of the time-delayed mutual information for a time-series is proposed. In particular, the bias of the time-delayed mutual information is shown to often be equivalent to the mutual information between two distributions of points from the same system separated by infinite time. Thus intuitively, estimation of the bias is reduced to estimation of the mutual information between distributions of data points separated by large time intervals. The proposed bias estimation techniques are shown to work for Lorenz equations data and glucose time series data of three patients from the Columbia University Medical Center database.

  13. Estimation of system parameters in discrete dynamical systems from time series

    International Nuclear Information System (INIS)

    Palaniyandi, P.; Lakshmanan, M.

    2005-01-01

    We propose a simple method to estimate the parameters involved in discrete dynamical systems from time series. The method is based on the concept of controlling chaos by constant feedback. The major advantages of the method are that it needs a minimal number of time series data (either vector or scalar) and is applicable to dynamical systems of any dimension. The method also works extremely well even in the presence of noise in the time series. The method is specifically illustrated by means of logistic and Henon maps

  14. The Implications of Summer Learning Loss for Value-Added Estimates of Teacher Effectiveness

    Science.gov (United States)

    Gershenson, Seth; Hayes, Michael S.

    2018-01-01

    School districts across the United States increasingly use value-added models (VAMs) to evaluate teachers. In practice, VAMs typically rely on lagged test scores from the previous academic year, which necessarily conflate summer with school-year learning and potentially bias estimates of teacher effectiveness. We investigate the practical…

  15. Effect of parameter calculation in direct estimation of the Lyapunov exponent in short time series

    Directory of Open Access Journals (Sweden)

    A. M. López Jiménez

    2002-01-01

    Full Text Available The literature about non-linear dynamics offers a few recommendations, which sometimes are divergent, about the criteria to be used in order to select the optimal calculus parameters in the estimation of Lyapunov exponents by direct methods. These few recommendations are circumscribed to the analysis of chaotic systems. We have found no recommendation for the estimation of λ starting from the time series of classic systems. The reason for this is the interest in distinguishing variability due to a chaotic behavior of determinist dynamic systems of variability caused by white noise or linear stochastic processes, and less in the identification of non-linear terms from the analysis of time series. In this study we have centered in the dependence of the Lyapunov exponent, obtained by means of direct estimation, of the initial distance and the time evolution. We have used generated series of chaotic systems and generated series of classic systems with varying complexity. To generate the series we have used the logistic map.

  16. Series load induction heating inverter state estimator using Kalman filter

    Directory of Open Access Journals (Sweden)

    Szelitzky T.

    2011-12-01

    Full Text Available LQR and H2 controllers require access to the states of the controlled system. The method based on description function with Fourier series results in a model with immeasurable states. For this reason, we proposed a Kalman filter based state estimator, which not only filters the input signals, but also computes the unobservable states of the system. The algorithm of the filter was implemented in LabVIEW v8.6 and tested on recorded data obtained from a 10-40 kHz series load frequency controlled induction heating inverter.

  17. On sharp estimates of the convergence of double Fourier-Bessel series

    Science.gov (United States)

    Abilov, V. A.; Abilova, F. V.; Kerimov, M. K.

    2017-11-01

    The problem of approximation of a differentiable function of two variables by partial sums of a double Fourier-Bessel series is considered. Sharp estimates of the rate of convergence of the double Fourier-Bessel series on the class of differentiable functions of two variables characterized by a generalized modulus of continuity are obtained. The proofs of four theorems on this issue, which can be directly applied to solving particular problems of mathematical physics, approximation theory, etc., are presented.

  18. Subtraction by Distraction: Publishing Value-Added Estimates of Teachers by Name Hinders Education Reform

    Science.gov (United States)

    Epstein, Diana; Miller, Raegen T.

    2011-01-01

    In August 2010 the "Los Angeles Times" published a special report on their website featuring performance ratings for nearly 6,000 Los Angeles Unified School District teachers. The move was controversial because the ratings were based on so-called value-added estimates of teachers' contributions to student learning. As with most…

  19. Estimation of Airborne Lidar-Derived Tropical Forest Canopy Height Using Landsat Time Series in Cambodia

    Directory of Open Access Journals (Sweden)

    Tetsuji Ota

    2014-11-01

    Full Text Available In this study, we test and demonstrate the utility of disturbance and recovery information derived from annual Landsat time series to predict current forest vertical structure (as compared to the more common approaches, that consider a sample of airborne Lidar and single-date Landsat derived variables. Mean Canopy Height (MCH was estimated separately using single date, time series, and the combination of single date and time series variables in multiple regression and random forest (RF models. The combination of single date and time series variables, which integrate disturbance history over the entire time series, overall provided better MCH prediction than using either of the two sets of variables separately. In general, the RF models resulted in improved performance in all estimates over those using multiple regression. The lowest validation error was obtained using Landsat time series variables in a RF model (R2 = 0.75 and RMSE = 2.81 m. Combining single date and time series data was more effective when the RF model was used (opposed to multiple regression. The RMSE for RF mean canopy height prediction was reduced by 13.5% when combining the two sets of variables as compared to the 3.6% RMSE decline presented by multiple regression. This study demonstrates the value of airborne Lidar and long term Landsat observations to generate estimates of forest canopy height using the random forest algorithm.

  20. A Sandwich-Type Standard Error Estimator of SEM Models with Multivariate Time Series

    Science.gov (United States)

    Zhang, Guangjian; Chow, Sy-Miin; Ong, Anthony D.

    2011-01-01

    Structural equation models are increasingly used as a modeling tool for multivariate time series data in the social and behavioral sciences. Standard error estimators of SEM models, originally developed for independent data, require modifications to accommodate the fact that time series data are inherently dependent. In this article, we extend a…

  1. Sensitivity of Hurst parameter estimation to periodic signals in time series and filtering approaches

    Science.gov (United States)

    Marković, D.; Koch, M.

    2005-09-01

    The influence of the periodic signals in time series on the Hurst parameter estimate is investigated with temporal, spectral and time-scale methods. The Hurst parameter estimates of the simulated periodic time series with a white noise background show a high sensitivity on the signal to noise ratio and for some methods, also on the data length used. The analysis is then carried on to the investigation of extreme monthly river flows of the Elbe River (Dresden) and of the Rhine River (Kaub). Effects of removing the periodic components employing different filtering approaches are discussed and it is shown that such procedures are a prerequisite for an unbiased estimation of H. In summary, our results imply that the first step in a time series long-correlation study should be the separation of the deterministic components from the stochastic ones. Otherwise wrong conclusions concerning possible memory effects may be drawn.

  2. An adaptive state of charge estimation approach for lithium-ion series-connected battery system

    Science.gov (United States)

    Peng, Simin; Zhu, Xuelai; Xing, Yinjiao; Shi, Hongbing; Cai, Xu; Pecht, Michael

    2018-07-01

    Due to the incorrect or unknown noise statistics of a battery system and its cell-to-cell variations, state of charge (SOC) estimation of a lithium-ion series-connected battery system is usually inaccurate or even divergent using model-based methods, such as extended Kalman filter (EKF) and unscented Kalman filter (UKF). To resolve this problem, an adaptive unscented Kalman filter (AUKF) based on a noise statistics estimator and a model parameter regulator is developed to accurately estimate the SOC of a series-connected battery system. An equivalent circuit model is first built based on the model parameter regulator that illustrates the influence of cell-to-cell variation on the battery system. A noise statistics estimator is then used to attain adaptively the estimated noise statistics for the AUKF when its prior noise statistics are not accurate or exactly Gaussian. The accuracy and effectiveness of the SOC estimation method is validated by comparing the developed AUKF and UKF when model and measurement statistics noises are inaccurate, respectively. Compared with the UKF and EKF, the developed method shows the highest SOC estimation accuracy.

  3. EIA completes corrections to drilling estimates series

    International Nuclear Information System (INIS)

    Trapmann, W.; Shambaugh, P.

    1998-01-01

    The Energy Information Administration (EIA) has published monthly and annual estimates of US oil and gas drilling activity since 1978. These data are key information for many industry analysts, serving as a leading indicator of trends in the industry and a barometer of general industry status. They are assessed directly for trends, as well as in combination with other measures to assess the productivity and profitability of upstream industry operations. They are major reference points for federal and state policymakers. EIA does not itself collect drilling activity data. Instead, it relies on an external source for data on oil, bas, and dry well completions. These data are provided to EIA monthly on an as reported basis. During a recent effort to enhance EIA's well completion data system, the detection of unusual patterns in the well completion data as received led to an expanded examination of these data. Substantial discrepancies between the data as received by EIA and correct record counts since 1987 were identified. For total wells by year, the errors ranged up to more than 2,300 wells, 11% of the 1995 total, and the impact of these errors extended backward in time to at least the early 1980s. When the magnitude and extent of the as reported well completion data problem were confirmed, EIA suspended its publication and distribution of updated drilling data. EIA staff proceeded to acquire replacement files with the as reported records and then revise the statistical portion of its drilling data system to reflect the new information. The replacement files unfortunately also included erroneous data based on the improper allocation of wells between exploration and development. EIA has now resolved the two data problems and generated revised time series estimates for well completions and footage drilled. The paper describes the problems in the data, differences between the series, and maintaining future data quality

  4. [Winter wheat area estimation with MODIS-NDVI time series based on parcel].

    Science.gov (United States)

    Li, Le; Zhang, Jin-shui; Zhu, Wen-quan; Hu, Tan-gao; Hou, Dong

    2011-05-01

    Several attributes of MODIS (moderate resolution imaging spectrometer) data, especially the short temporal intervals and the global coverage, provide an extremely efficient way to map cropland and monitor its seasonal change. However, the reliability of their measurement results is challenged because of the limited spatial resolution. The parcel data has clear geo-location and obvious boundary information of cropland. Also, the spectral differences and the complexity of mixed pixels are weak in parcels. All of these make that area estimation based on parcels presents more advantage than on pixels. In the present study, winter wheat area estimation based on MODIS-NDVI time series has been performed with the support of cultivated land parcel in Tongzhou, Beijing. In order to extract the regional winter wheat acreage, multiple regression methods were used to simulate the stable regression relationship between MODIS-NDVI time series data and TM samples in parcels. Through this way, the consistency of the extraction results from MODIS and TM can stably reach up to 96% when the amount of samples accounts for 15% of the whole area. The results shows that the use of parcel data can effectively improve the error in recognition results in MODIS-NDVI based multi-series data caused by the low spatial resolution. Therefore, with combination of moderate and low resolution data, the winter wheat area estimation became available in large-scale region which lacks completed medium resolution images or has images covered with clouds. Meanwhile, it carried out the preliminary experiments for other crop area estimation.

  5. Statistical methods of parameter estimation for deterministically chaotic time series

    Science.gov (United States)

    Pisarenko, V. F.; Sornette, D.

    2004-03-01

    We discuss the possibility of applying some standard statistical methods (the least-square method, the maximum likelihood method, and the method of statistical moments for estimation of parameters) to deterministically chaotic low-dimensional dynamic system (the logistic map) containing an observational noise. A “segmentation fitting” maximum likelihood (ML) method is suggested to estimate the structural parameter of the logistic map along with the initial value x1 considered as an additional unknown parameter. The segmentation fitting method, called “piece-wise” ML, is similar in spirit but simpler and has smaller bias than the “multiple shooting” previously proposed. Comparisons with different previously proposed techniques on simulated numerical examples give favorable results (at least, for the investigated combinations of sample size N and noise level). Besides, unlike some suggested techniques, our method does not require the a priori knowledge of the noise variance. We also clarify the nature of the inherent difficulties in the statistical analysis of deterministically chaotic time series and the status of previously proposed Bayesian approaches. We note the trade off between the need of using a large number of data points in the ML analysis to decrease the bias (to guarantee consistency of the estimation) and the unstable nature of dynamical trajectories with exponentially fast loss of memory of the initial condition. The method of statistical moments for the estimation of the parameter of the logistic map is discussed. This method seems to be the unique method whose consistency for deterministically chaotic time series is proved so far theoretically (not only numerically).

  6. Two-pass imputation algorithm for missing value estimation in gene expression time series.

    Science.gov (United States)

    Tsiporkova, Elena; Boeva, Veselka

    2007-10-01

    Gene expression microarray experiments frequently generate datasets with multiple values missing. However, most of the analysis, mining, and classification methods for gene expression data require a complete matrix of gene array values. Therefore, the accurate estimation of missing values in such datasets has been recognized as an important issue, and several imputation algorithms have already been proposed to the biological community. Most of these approaches, however, are not particularly suitable for time series expression profiles. In view of this, we propose a novel imputation algorithm, which is specially suited for the estimation of missing values in gene expression time series data. The algorithm utilizes Dynamic Time Warping (DTW) distance in order to measure the similarity between time expression profiles, and subsequently selects for each gene expression profile with missing values a dedicated set of candidate profiles for estimation. Three different DTW-based imputation (DTWimpute) algorithms have been considered: position-wise, neighborhood-wise, and two-pass imputation. These have initially been prototyped in Perl, and their accuracy has been evaluated on yeast expression time series data using several different parameter settings. The experiments have shown that the two-pass algorithm consistently outperforms, in particular for datasets with a higher level of missing entries, the neighborhood-wise and the position-wise algorithms. The performance of the two-pass DTWimpute algorithm has further been benchmarked against the weighted K-Nearest Neighbors algorithm, which is widely used in the biological community; the former algorithm has appeared superior to the latter one. Motivated by these findings, indicating clearly the added value of the DTW techniques for missing value estimation in time series data, we have built an optimized C++ implementation of the two-pass DTWimpute algorithm. The software also provides for a choice between three different

  7. Nonparametric trend estimation in the presence of fractal noise: application to fMRI time-series analysis.

    Science.gov (United States)

    Afshinpour, Babak; Hossein-Zadeh, Gholam-Ali; Soltanian-Zadeh, Hamid

    2008-06-30

    Unknown low frequency fluctuations called "trend" are observed in noisy time-series measured for different applications. In some disciplines, they carry primary information while in other fields such as functional magnetic resonance imaging (fMRI) they carry nuisance effects. In all cases, however, it is necessary to estimate them accurately. In this paper, a method for estimating trend in the presence of fractal noise is proposed and applied to fMRI time-series. To this end, a partly linear model (PLM) is fitted to each time-series. The parametric and nonparametric parts of PLM are considered as contributions of hemodynamic response and trend, respectively. Using the whitening property of wavelet transform, the unknown components of the model are estimated in the wavelet domain. The results of the proposed method are compared to those of other parametric trend-removal approaches such as spline and polynomial models. It is shown that the proposed method improves activation detection and decreases variance of the estimated parameters relative to the other methods.

  8. A propagation-separation approach to estimate the autocorrelation in a time-series

    Directory of Open Access Journals (Sweden)

    D. V. Divine

    2008-07-01

    Full Text Available The paper presents an approach to estimate parameters of a local stationary AR(1 time series model by maximization of a local likelihood function. The method is based on a propagation-separation procedure that leads to data dependent weights defining the local model. Using free propagation of weights under homogeneity, the method is capable of separating the time series into intervals of approximate local stationarity. Parameters in different regions will be significantly different. Therefore the method also serves as a test for a stationary AR(1 model. The performance of the method is illustrated by applications to both synthetic data and real time-series of reconstructed NAO and ENSO indices and GRIP stable isotopes.

  9. Estimation of coefficients of multivariable power series approximating magnetic nonlinearity of AC machines*

    Directory of Open Access Journals (Sweden)

    Sobczyk Tadeusz J.

    2015-09-01

    Full Text Available Energy based approach was used in the study to formulate a set of functions approximating the magnetic flux linkages versus independent currents. The simplest power series that approximates field co-energy and linked fluxes for a two winding core of an induction machine are described by a set of common unknown coefficients. The authors tested three algorithms for the coefficient estimation using Weighted Least-Squared Method for two different positions of the coils. The comparison of the approximation accuracy was accomplished in the specified area of the currents. All proposed algorithms of the coefficient estimation have been found to be effective. The algorithm based solely on the magnetic field co-energy values is significantly simpler than the method based on the magnetic flux linkages estimation concept. The algorithm based on the field co-energy and linked fluxes seems to be the most suitable for determining simultaneously the coefficients of power series approximating linked fluxes and field co-energy.

  10. Online Reliable Peak Charge/Discharge Power Estimation of Series-Connected Lithium-Ion Battery Packs

    Directory of Open Access Journals (Sweden)

    Bo Jiang

    2017-03-01

    Full Text Available The accurate peak power estimation of a battery pack is essential to the power-train control of electric vehicles (EVs. It helps to evaluate the maximum charge and discharge capability of the battery system, and thus to optimally control the power-train system to meet the requirement of acceleration, gradient climbing and regenerative braking while achieving a high energy efficiency. A novel online peak power estimation method for series-connected lithium-ion battery packs is proposed, which considers the influence of cell difference on the peak power of the battery packs. A new parameter identification algorithm based on adaptive ratio vectors is designed to online identify the parameters of each individual cell in a series-connected battery pack. The ratio vectors reflecting cell difference are deduced strictly based on the analysis of battery characteristics. Based on the online parameter identification, the peak power estimation considering cell difference is further developed. Some validation experiments in different battery aging conditions and with different current profiles have been implemented to verify the proposed method. The results indicate that the ratio vector-based identification algorithm can achieve the same accuracy as the repetitive RLS (recursive least squares based identification while evidently reducing the computation cost, and the proposed peak power estimation method is more effective and reliable for series-connected battery packs due to the consideration of cell difference.

  11. Assessing the Potential of Using Value-Added Estimates of Teacher Job Performance for Making Tenure Decisions. Working Paper 31

    Science.gov (United States)

    Goldhaber, Dan; Hansen, Michael

    2010-01-01

    Reforming teacher tenure is an idea that appears to be gaining traction with the underlying assumption being that one can infer to a reasonable degree how well a teacher will perform over her career based on estimates of her early-career effectiveness. Here we explore the potential for using value-added models to estimate performance and inform…

  12. Teacher Costs

    OpenAIRE

    DINIS MOTA DA COSTA PATRICIA; DE SOUSA LOBO BORGES DE ARAUJO LUISA

    2015-01-01

    The purpose of this technical brief is to assess current methodologies for the collection and calculation of teacher costs in European Union (EU) Member States in view of improving data series and indicators related to teacher salaries and teacher costs. To this end, CRELL compares the Eurydice collection on teacher salaries with the similar Organisation for Economic Co-operation and Development (OECD) data collection and calculates teacher costs based on the methodology established by Statis...

  13. Bad Teacher! How Blaming Teachers Distorts the Bigger Picture. Teaching for Social Justice Series

    Science.gov (United States)

    Kumashiro, Kevin K.

    2012-01-01

    In his latest book, leading educator and author Kevin Kumashiro takes aim at the current debate on educational reform, paying particular attention to the ways that scapegoating public school teachers, teacher unions, and teacher educators masks the real, systemic problems. He convincingly demonstrates how current trends, like market-based reforms…

  14. Transfer Entropy Estimation and Directional Coupling Change Detection in Biomedical Time Series

    Directory of Open Access Journals (Sweden)

    Lee Joon

    2012-04-01

    Full Text Available Abstract Background The detection of change in magnitude of directional coupling between two non-linear time series is a common subject of interest in the biomedical domain, including studies involving the respiratory chemoreflex system. Although transfer entropy is a useful tool in this avenue, no study to date has investigated how different transfer entropy estimation methods perform in typical biomedical applications featuring small sample size and presence of outliers. Methods With respect to detection of increased coupling strength, we compared three transfer entropy estimation techniques using both simulated time series and respiratory recordings from lambs. The following estimation methods were analyzed: fixed-binning with ranking, kernel density estimation (KDE, and the Darbellay-Vajda (D-V adaptive partitioning algorithm extended to three dimensions. In the simulated experiment, sample size was varied from 50 to 200, while coupling strength was increased. In order to introduce outliers, the heavy-tailed Laplace distribution was utilized. In the lamb experiment, the objective was to detect increased respiratory-related chemosensitivity to O2 and CO2 induced by a drug, domperidone. Specifically, the separate influence of end-tidal PO2 and PCO2 on minute ventilation (V˙E before and after administration of domperidone was analyzed. Results In the simulation, KDE detected increased coupling strength at the lowest SNR among the three methods. In the lamb experiment, D-V partitioning resulted in the statistically strongest increase in transfer entropy post-domperidone for PO2→V˙E. In addition, D-V partitioning was the only method that could detect an increase in transfer entropy for PCO2→V˙E, in agreement with experimental findings. Conclusions Transfer entropy is capable of detecting directional coupling changes in non-linear biomedical time series analysis featuring a small number of observations and presence of outliers. The results

  15. Uncertainty estimation with bias-correction for flow series based on rating curve

    Science.gov (United States)

    Shao, Quanxi; Lerat, Julien; Podger, Geoff; Dutta, Dushmanta

    2014-03-01

    Streamflow discharge constitutes one of the fundamental data required to perform water balance studies and develop hydrological models. A rating curve, designed based on a series of concurrent stage and discharge measurements at a gauging location, provides a way to generate complete discharge time series with a reasonable quality if sufficient measurement points are available. However, the associated uncertainty is frequently not available even though it has a significant impact on hydrological modelling. In this paper, we identify the discrepancy of the hydrographers' rating curves used to derive the historical discharge data series and proposed a modification by bias correction which is also in the form of power function as the traditional rating curve. In order to obtain the uncertainty estimation, we propose a further both-side Box-Cox transformation to stabilize the regression residuals as close to the normal distribution as possible, so that a proper uncertainty can be attached for the whole discharge series in the ensemble generation. We demonstrate the proposed method by applying it to the gauging stations in the Flinders and Gilbert rivers in north-west Queensland, Australia.

  16. Informing Estimates of Program Effects for Studies of Mathematics Professional Development Using Teacher Content Knowledge Outcomes.

    Science.gov (United States)

    Phelps, Geoffrey; Kelcey, Benjamin; Jones, Nathan; Liu, Shuangshuang

    2016-10-03

    Mathematics professional development is widely offered, typically with the goal of improving teachers' content knowledge, the quality of teaching, and ultimately students' achievement. Recently, new assessments focused on mathematical knowledge for teaching (MKT) have been developed to assist in the evaluation and improvement of mathematics professional development. This study presents empirical estimates of average program change in MKT and its variation with the goal of supporting the design of experimental trials that are adequately powered to detect a specified program effect. The study drew on a large database representing five different assessments of MKT and collectively 326 professional development programs and 9,365 teachers. Results from cross-classified hierarchical growth models found that standardized average change estimates across the five assessments ranged from a low of 0.16 standard deviations (SDs) to a high of 0.26 SDs. Power analyses using the estimated pre- and posttest change estimates indicated that hundreds of teachers are needed to detect changes in knowledge at the lower end of the distribution. Even studies powered to detect effects at the higher end of the distribution will require substantial resources to conduct rigorous experimental trials. Empirical benchmarks that describe average program change and its variation provide a useful preliminary resource for interpreting the relative magnitude of effect sizes associated with professional development programs and for designing adequately powered trials. © The Author(s) 2016.

  17. The MetLife Survey of the American Teacher: Listening to Teachers in Rural Schools

    Science.gov (United States)

    MetLife, Inc., 2013

    2013-01-01

    MetLife has sponsored and Harris Interactive has conducted the annual MetLife Survey of the American Teacher series since 1984 to share the voices of teachers with educators, policymakers and the public. The series examines significant changes and trends over time, highlights important current issues, and explores topics relevant to the future of…

  18. Estimation of unemployment rates using small area estimation model by combining time series and cross-sectional data

    Science.gov (United States)

    Muchlisoh, Siti; Kurnia, Anang; Notodiputro, Khairil Anwar; Mangku, I. Wayan

    2016-02-01

    Labor force surveys conducted over time by the rotating panel design have been carried out in many countries, including Indonesia. Labor force survey in Indonesia is regularly conducted by Statistics Indonesia (Badan Pusat Statistik-BPS) and has been known as the National Labor Force Survey (Sakernas). The main purpose of Sakernas is to obtain information about unemployment rates and its changes over time. Sakernas is a quarterly survey. The quarterly survey is designed only for estimating the parameters at the provincial level. The quarterly unemployment rate published by BPS (official statistics) is calculated based on only cross-sectional methods, despite the fact that the data is collected under rotating panel design. The study purpose to estimate a quarterly unemployment rate at the district level used small area estimation (SAE) model by combining time series and cross-sectional data. The study focused on the application and comparison between the Rao-Yu model and dynamic model in context estimating the unemployment rate based on a rotating panel survey. The goodness of fit of both models was almost similar. Both models produced an almost similar estimation and better than direct estimation, but the dynamic model was more capable than the Rao-Yu model to capture a heterogeneity across area, although it was reduced over time.

  19. Most probable dimension value and most flat interval methods for automatic estimation of dimension from time series

    International Nuclear Information System (INIS)

    Corana, A.; Bortolan, G.; Casaleggio, A.

    2004-01-01

    We present and compare two automatic methods for dimension estimation from time series. Both methods, based on conceptually different approaches, work on the derivative of the bi-logarithmic plot of the correlation integral versus the correlation length (log-log plot). The first method searches for the most probable dimension values (MPDV) and associates to each of them a possible scaling region. The second one searches for the most flat intervals (MFI) in the derivative of the log-log plot. The automatic procedures include the evaluation of the candidate scaling regions using two reliability indices. The data set used to test the methods consists of time series from known model attractors with and without the addition of noise, structured time series, and electrocardiographic signals from the MIT-BIH ECG database. Statistical analysis of results was carried out by means of paired t-test, and no statistically significant differences were found in the large majority of the trials. Consistent results are also obtained dealing with 'difficult' time series. In general for a more robust and reliable estimate, the use of both methods may represent a good solution when time series from complex systems are analyzed. Although we present results for the correlation dimension only, the procedures can also be used for the automatic estimation of generalized q-order dimensions and pointwise dimension. We think that the proposed methods, eliminating the need of operator intervention, allow a faster and more objective analysis, thus improving the usefulness of dimension analysis for the characterization of time series obtained from complex dynamical systems

  20. Generalized least squares and empirical Bayes estimation in regional partial duration series index-flood modeling

    DEFF Research Database (Denmark)

    Madsen, Henrik; Rosbjerg, Dan

    1997-01-01

    parameters is inferred from regional data using generalized least squares (GLS) regression. Two different Bayesian T-year event estimators are introduced: a linear estimator that requires only some moments of the prior distributions to be specified and a parametric estimator that is based on specified......A regional estimation procedure that combines the index-flood concept with an empirical Bayes method for inferring regional information is introduced. The model is based on the partial duration series approach with generalized Pareto (GP) distributed exceedances. The prior information of the model...

  1. Autoregressive-model-based missing value estimation for DNA microarray time series data.

    Science.gov (United States)

    Choong, Miew Keen; Charbit, Maurice; Yan, Hong

    2009-01-01

    Missing value estimation is important in DNA microarray data analysis. A number of algorithms have been developed to solve this problem, but they have several limitations. Most existing algorithms are not able to deal with the situation where a particular time point (column) of the data is missing entirely. In this paper, we present an autoregressive-model-based missing value estimation method (ARLSimpute) that takes into account the dynamic property of microarray temporal data and the local similarity structures in the data. ARLSimpute is especially effective for the situation where a particular time point contains many missing values or where the entire time point is missing. Experiment results suggest that our proposed algorithm is an accurate missing value estimator in comparison with other imputation methods on simulated as well as real microarray time series datasets.

  2. HMGCR-associated myositis: a New Zealand case series and estimate of incidence.

    Science.gov (United States)

    Kennedy, N; Keating, P; O'Donnell, J

    2016-05-01

    Statins are one of the most commonly prescribed drugs in New Zealand, with 525 772 or 16.5% of the adult New Zealand population prescribed a statin between June 2013 and July 2014. While generally well-tolerated, statins are known to cause a range of muscle-related side effects, ranging from myalgia to life-threatening rhabdomyolysis. Recently, it has been recognised that in rare instances, statins can induce an immune-mediated necrotising myositis with antibodies against 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR), the enzymatic target of statins. In 2014, anti-HMGCR antibody testing was introduced to Canterbury Health Laboratories (CHL), with this being the only laboratory in New Zealand performing this test during the period of this case series. This article describes an index case and characterises the clinical features of a subsequent 12-month series. From this series, we estimated the yearly incidence of HMGCR-associated myositis at 1.7/million/year or ~1/90 000 New Zealand statin users. © 2016 Royal Australasian College of Physicians.

  3. Preparacion e Iniciacion de la Lectura en Espanol para Maestros de Programas Bilingues. Serie Tierra de Encanto (Preparation and Initiation of Reading in Spanish for Teachers of Bilingual Programs. Land of Enchantment Series).

    Science.gov (United States)

    New Mexico Univ., Albuquerque.

    Part of the "Land of Enchantment" series of instructional materials, this very detailed teaching manual is designed to help teachers in bilingual programs prepare students to read Spanish. It contains suggestions for developing reading readiness skills and ways to teach a basic 30-word reading vocabulary. The reading program follows five steps:…

  4. Trend Estimation and Regression Analysis in Climatological Time Series: An Application of Structural Time Series Models and the Kalman Filter.

    Science.gov (United States)

    Visser, H.; Molenaar, J.

    1995-05-01

    The detection of trends in climatological data has become central to the discussion on climate change due to the enhanced greenhouse effect. To prove detection, a method is needed (i) to make inferences on significant rises or declines in trends, (ii) to take into account natural variability in climate series, and (iii) to compare output from GCMs with the trends in observed climate data. To meet these requirements, flexible mathematical tools are needed. A structural time series model is proposed with which a stochastic trend, a deterministic trend, and regression coefficients can be estimated simultaneously. The stochastic trend component is described using the class of ARIMA models. The regression component is assumed to be linear. However, the regression coefficients corresponding with the explanatory variables may be time dependent to validate this assumption. The mathematical technique used to estimate this trend-regression model is the Kaiman filter. The main features of the filter are discussed.Examples of trend estimation are given using annual mean temperatures at a single station in the Netherlands (1706-1990) and annual mean temperatures at Northern Hemisphere land stations (1851-1990). The inclusion of explanatory variables is shown by regressing the latter temperature series on four variables: Southern Oscillation index (SOI), volcanic dust index (VDI), sunspot numbers (SSN), and a simulated temperature signal, induced by increasing greenhouse gases (GHG). In all analyses, the influence of SSN on global temperatures is found to be negligible. The correlations between temperatures and SOI and VDI appear to be negative. For SOI, this correlation is significant, but for VDI it is not, probably because of a lack of volcanic eruptions during the sample period. The relation between temperatures and GHG is positive, which is in agreement with the hypothesis of a warming climate because of increasing levels of greenhouse gases. The prediction performance of

  5. Estimating the Persistence and the Autocorrelation Function of a Time Series that is Measured with Error

    DEFF Research Database (Denmark)

    Hansen, Peter Reinhard; Lunde, Asger

    An economic time series can often be viewed as a noisy proxy for an underlying economic variable. Measurement errors will influence the dynamic properties of the observed process and may conceal the persistence of the underlying time series. In this paper we develop instrumental variable (IV...... application despite the large sample. Unit root tests based on the IV estimator have better finite sample properties in this context....

  6. Error estimation in multitemporal InSAR deformation time series, with application to Lanzarote, Canary Islands

    Science.gov (United States)

    GonzáLez, Pablo J.; FernáNdez, José

    2011-10-01

    Interferometric Synthetic Aperture Radar (InSAR) is a reliable technique for measuring crustal deformation. However, despite its long application in geophysical problems, its error estimation has been largely overlooked. Currently, the largest problem with InSAR is still the atmospheric propagation errors, which is why multitemporal interferometric techniques have been successfully developed using a series of interferograms. However, none of the standard multitemporal interferometric techniques, namely PS or SB (Persistent Scatterers and Small Baselines, respectively) provide an estimate of their precision. Here, we present a method to compute reliable estimates of the precision of the deformation time series. We implement it for the SB multitemporal interferometric technique (a favorable technique for natural terrains, the most usual target of geophysical applications). We describe the method that uses a properly weighted scheme that allows us to compute estimates for all interferogram pixels, enhanced by a Montecarlo resampling technique that properly propagates the interferogram errors (variance-covariances) into the unknown parameters (estimated errors for the displacements). We apply the multitemporal error estimation method to Lanzarote Island (Canary Islands), where no active magmatic activity has been reported in the last decades. We detect deformation around Timanfaya volcano (lengthening of line-of-sight ˜ subsidence), where the last eruption in 1730-1736 occurred. Deformation closely follows the surface temperature anomalies indicating that magma crystallization (cooling and contraction) of the 300-year shallow magmatic body under Timanfaya volcano is still ongoing.

  7. Quasi-Maximum Likelihood Estimation and Bootstrap Inference in Fractional Time Series Models with Heteroskedasticity of Unknown Form

    DEFF Research Database (Denmark)

    Cavaliere, Giuseppe; Nielsen, Morten Ørregaard; Taylor, Robert

    We consider the problem of conducting estimation and inference on the parameters of univariate heteroskedastic fractionally integrated time series models. We first extend existing results in the literature, developed for conditional sum-of squares estimators in the context of parametric fractional...... time series models driven by conditionally homoskedastic shocks, to allow for conditional and unconditional heteroskedasticity both of a quite general and unknown form. Global consistency and asymptotic normality are shown to still obtain; however, the covariance matrix of the limiting distribution...... of the estimator now depends on nuisance parameters derived both from the weak dependence and heteroskedasticity present in the shocks. We then investigate classical methods of inference based on the Wald, likelihood ratio and Lagrange multiplier tests for linear hypotheses on either or both of the long and short...

  8. Solutions for the diurnally forced advection-diffusion equation to estimate bulk fluid velocity and diffusivity in streambeds from temperature time series

    Science.gov (United States)

    Charles H. Luce; Daniele Tonina; Frank Gariglio; Ralph Applebee

    2013-01-01

    Work over the last decade has documented methods for estimating fluxes between streams and streambeds from time series of temperature at two depths in the streambed. We present substantial extension to the existing theory and practice of using temperature time series to estimate streambed water fluxes and thermal properties, including (1) a new explicit analytical...

  9. Asymptotics for the conditional-sum-of-squares estimator in multivariate fractional time series models

    DEFF Research Database (Denmark)

    Ørregård Nielsen, Morten

    This paper proves consistency and asymptotic normality for the conditional-sum-of-squares estimator, which is equivalent to the conditional maximum likelihood estimator, in multivariate fractional time series models. The model is parametric and quite general, and, in particular, encompasses...... the multivariate non-cointegrated fractional ARIMA model. The novelty of the consistency result, in particular, is that it applies to a multivariate model and to an arbitrarily large set of admissible parameter values, for which the objective function does not converge uniformly in probablity, thus making...

  10. A regressive methodology for estimating missing data in rainfall daily time series

    Science.gov (United States)

    Barca, E.; Passarella, G.

    2009-04-01

    The "presence" of gaps in environmental data time series represents a very common, but extremely critical problem, since it can produce biased results (Rubin, 1976). Missing data plagues almost all surveys. The problem is how to deal with missing data once it has been deemed impossible to recover the actual missing values. Apart from the amount of missing data, another issue which plays an important role in the choice of any recovery approach is the evaluation of "missingness" mechanisms. When data missing is conditioned by some other variable observed in the data set (Schafer, 1997) the mechanism is called MAR (Missing at Random). Otherwise, when the missingness mechanism depends on the actual value of the missing data, it is called NCAR (Not Missing at Random). This last is the most difficult condition to model. In the last decade interest arose in the estimation of missing data by using regression (single imputation). More recently multiple imputation has become also available, which returns a distribution of estimated values (Scheffer, 2002). In this paper an automatic methodology for estimating missing data is presented. In practice, given a gauging station affected by missing data (target station), the methodology checks the randomness of the missing data and classifies the "similarity" between the target station and the other gauging stations spread over the study area. Among different methods useful for defining the similarity degree, whose effectiveness strongly depends on the data distribution, the Spearman correlation coefficient was chosen. Once defined the similarity matrix, a suitable, nonparametric, univariate, and regressive method was applied in order to estimate missing data in the target station: the Theil method (Theil, 1950). Even though the methodology revealed to be rather reliable an improvement of the missing data estimation can be achieved by a generalization. A first possible improvement consists in extending the univariate technique to

  11. Parameter estimation methods for gene circuit modeling from time-series mRNA data: a comparative study

    KAUST Repository

    Fan, M.; Kuwahara, Hiroyuki; Wang, X.; Wang, S.; Gao, Xin

    2015-01-01

    Parameter estimation is a challenging computational problemin the reverse engineering of biological systems. Because advances in biotechnology have facilitated wide availability of time-series gene expression data, systematic parameter esti- mation

  12. Estimating primary production from oxygen time series: A novel approach in the frequency domain

    NARCIS (Netherlands)

    Cox, T.J.S.; Maris, T.; Soetaert, K.; Kromkamp, J.C.; Meire, P.; Meysman, F.J.R.

    2015-01-01

    Based on an analysis in the frequency domain of the governing equation of oxygen dynamics in aquatic systems, we derive a new method for estimating gross primary production (GPP) from oxygen time series. The central result of this article is a relation between time averaged GPP and the amplitude of

  13. Teacher Resource Book for Population Pressure in Indonesia, Problems of Industrialization in Eurasia, Power Blocs in Eurasia. Man on the Earth Series.

    Science.gov (United States)

    Gunn, Angus

    This teacher's resource book is a guide to three intermediate texts about Eurasia entitled Population Pressure in Indonesia, Problems of Industrialization in Eurasia, and Power Blocs in Eurasia. The texts are part of the series, Man on the Earth, which probes broad-based issues confronting mankind. The resource book distinguishes 18 major concepts…

  14. Estimating serial correlation and self-similarity in financial time series-A diversification approach with applications to high frequency data

    Science.gov (United States)

    Gerlich, Nikolas; Rostek, Stefan

    2015-09-01

    We derive a heuristic method to estimate the degree of self-similarity and serial correlation in financial time series. Especially, we propagate the use of a tailor-made selection of different estimation techniques that are used in various fields of time series analysis but until now have not consequently found their way into the finance literature. Following the idea of portfolio diversification, we show that considerable improvements with respect to robustness and unbiasedness can be achieved by using a basket of estimation methods. With this methodological toolbox at hand, we investigate real market data to show that noticeable deviations from the assumptions of constant self-similarity and absence of serial correlation occur during certain periods. On the one hand, this may shed a new light on seemingly ambiguous scientific findings concerning serial correlation of financial time series. On the other hand, a proven time-changing degree of self-similarity may help to explain high-volatility clusters of stock price indices.

  15. Teachers' Views on the Impact of Teacher-Student Relationships on School Dropout: A Bourdieusian Analysis of Misrecognition

    Science.gov (United States)

    Nairz-Wirth, Erna; Feldmann, Klaus

    2017-01-01

    Drawing on Pierre Bourdieu's relational theory this paper shows that many teachers misrecognize the impact of teacher-student relationships on school dropout. The study is based on a series of 60 semi-structured interviews with teachers from Austrian secondary schools. The analysis of the empirical data reveals that many teachers attribute school…

  16. Improved vertical streambed flux estimation using multiple diurnal temperature methods in series

    Science.gov (United States)

    Irvine, Dylan J.; Briggs, Martin A.; Cartwright, Ian; Scruggs, Courtney; Lautz, Laura K.

    2017-01-01

    Analytical solutions that use diurnal temperature signals to estimate vertical fluxes between groundwater and surface water based on either amplitude ratios (Ar) or phase shifts (Δϕ) produce results that rarely agree. Analytical solutions that simultaneously utilize Ar and Δϕ within a single solution have more recently been derived, decreasing uncertainty in flux estimates in some applications. Benefits of combined (ArΔϕ) methods also include that thermal diffusivity and sensor spacing can be calculated. However, poor identification of either Ar or Δϕ from raw temperature signals can lead to erratic parameter estimates from ArΔϕ methods. An add-on program for VFLUX 2 is presented to address this issue. Using thermal diffusivity selected from an ArΔϕ method during a reliable time period, fluxes are recalculated using an Ar method. This approach maximizes the benefits of the Ar and ArΔϕ methods. Additionally, sensor spacing calculations can be used to identify periods with unreliable flux estimates, or to assess streambed scour. Using synthetic and field examples, the use of these solutions in series was particularly useful for gaining conditions where fluxes exceeded 1 m/d.

  17. Estimation of the order of an autoregressive time series: a Bayesian approach

    International Nuclear Information System (INIS)

    Robb, L.J.

    1980-01-01

    Finite-order autoregressive models for time series are often used for prediction and other inferences. Given the order of the model, the parameters of the models can be estimated by least-squares, maximum-likelihood, or Yule-Walker method. The basic problem is estimating the order of the model. The problem of autoregressive order estimation is placed in a Bayesian framework. This approach illustrates how the Bayesian method brings the numerous aspects of the problem together into a coherent structure. A joint prior probability density is proposed for the order, the partial autocorrelation coefficients, and the variance; and the marginal posterior probability distribution for the order, given the data, is obtained. It is noted that the value with maximum posterior probability is the Bayes estimate of the order with respect to a particular loss function. The asymptotic posterior distribution of the order is also given. In conclusion, Wolfer's sunspot data as well as simulated data corresponding to several autoregressive models are analyzed according to Akaike's method and the Bayesian method. Both methods are observed to perform quite well, although the Bayesian method was clearly superior, in most cases

  18. Lag space estimation in time series modelling

    DEFF Research Database (Denmark)

    Goutte, Cyril

    1997-01-01

    The purpose of this article is to investigate some techniques for finding the relevant lag-space, i.e. input information, for time series modelling. This is an important aspect of time series modelling, as it conditions the design of the model through the regressor vector a.k.a. the input layer...

  19. Child-to-Teacher Ratio and Day-Care Teacher Sickness Absenteeism

    DEFF Research Database (Denmark)

    Andersson, Elvira; Gørtz, Mette

    2013-01-01

    -to-teacher ratio, i.e. the number of children per teacher in an institution, affects teacher sickness absenteeism. We control for individual teacher characteristics, workplace characteristics, and family background characteristics of the children in the day-care institutions. Our estimation results indicate...... that the child-to-teacher ratio is positively related to sickness absence for 2005-2006, but not for 2002-2004....

  20. Brakes Specialist. Teacher Edition. Automotive Service Series.

    Science.gov (United States)

    Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    This document contains teacher's materials for a course on becoming an automotive brakes specialist, based on the National Institute of Automotive Service Excellence task lists. The course consists of three instructional units: service brake hydraulic system and wheel bearings, service drum brakes, and service disc brakes. Depending on the…

  1. "Feeling" Series and Parallel Resistances.

    Science.gov (United States)

    Morse, Robert A.

    1993-01-01

    Equipped with drinking straws and stirring straws, a teacher can help students understand how resistances in electric circuits combine in series and in parallel. Follow-up suggestions are provided. (ZWH)

  2. A method for the estimation of the significance of cross-correlations in unevenly sampled red-noise time series

    Science.gov (United States)

    Max-Moerbeck, W.; Richards, J. L.; Hovatta, T.; Pavlidou, V.; Pearson, T. J.; Readhead, A. C. S.

    2014-11-01

    We present a practical implementation of a Monte Carlo method to estimate the significance of cross-correlations in unevenly sampled time series of data, whose statistical properties are modelled with a simple power-law power spectral density. This implementation builds on published methods; we introduce a number of improvements in the normalization of the cross-correlation function estimate and a bootstrap method for estimating the significance of the cross-correlations. A closely related matter is the estimation of a model for the light curves, which is critical for the significance estimates. We present a graphical and quantitative demonstration that uses simulations to show how common it is to get high cross-correlations for unrelated light curves with steep power spectral densities. This demonstration highlights the dangers of interpreting them as signs of a physical connection. We show that by using interpolation and the Hanning sampling window function we are able to reduce the effects of red-noise leakage and to recover steep simple power-law power spectral densities. We also introduce the use of a Neyman construction for the estimation of the errors in the power-law index of the power spectral density. This method provides a consistent way to estimate the significance of cross-correlations in unevenly sampled time series of data.

  3. A Hierarchical Approach to Persistent Scatterer Network Construction and Deformation Time Series Estimation

    Directory of Open Access Journals (Sweden)

    Rui Zhang

    2014-12-01

    Full Text Available This paper presents a hierarchical approach to network construction and time series estimation in persistent scatterer interferometry (PSI for deformation analysis using the time series of high-resolution satellite SAR images. To balance between computational efficiency and solution accuracy, a dividing and conquering algorithm (i.e., two levels of PS networking and solution is proposed for extracting deformation rates of a study area. The algorithm has been tested using 40 high-resolution TerraSAR-X images collected between 2009 and 2010 over Tianjin in China for subsidence analysis, and validated by using the ground-based leveling measurements. The experimental results indicate that the hierarchical approach can remarkably reduce computing time and memory requirements, and the subsidence measurements derived from the hierarchical solution are in good agreement with the leveling data.

  4. Estimating Cause: Teacher Turnover and School Effectiveness in Michigan

    Science.gov (United States)

    Keesler, Venessa; Schneider, Barbara

    2010-01-01

    The purpose of this paper is investigate issues related to within-school teacher supply and school-specific teacher turnover within the state of Michigan using state administrative data on Michigan's teaching force. This paper 1) investigates the key predictors of teacher turnover and mobility, 2) develops a profile of schools that are likely to…

  5. Advanced methods for modeling water-levels and estimating drawdowns with SeriesSEE, an Excel add-in

    Science.gov (United States)

    Halford, Keith; Garcia, C. Amanda; Fenelon, Joe; Mirus, Benjamin B.

    2012-12-21

    Water-level modeling is used for multiple-well aquifer tests to reliably differentiate pumping responses from natural water-level changes in wells, or “environmental fluctuations.” Synthetic water levels are created during water-level modeling and represent the summation of multiple component fluctuations, including those caused by environmental forcing and pumping. Pumping signals are modeled by transforming step-wise pumping records into water-level changes by using superimposed Theis functions. Water-levels can be modeled robustly with this Theis-transform approach because environmental fluctuations and pumping signals are simulated simultaneously. Water-level modeling with Theis transforms has been implemented in the program SeriesSEE, which is a Microsoft® Excel add-in. Moving average, Theis, pneumatic-lag, and gamma functions transform time series of measured values into water-level model components in SeriesSEE. Earth tides and step transforms are additional computed water-level model components. Water-level models are calibrated by minimizing a sum-of-squares objective function where singular value decomposition and Tikhonov regularization stabilize results. Drawdown estimates from a water-level model are the summation of all Theis transforms minus residual differences between synthetic and measured water levels. The accuracy of drawdown estimates is limited primarily by noise in the data sets, not the Theis-transform approach. Drawdowns much smaller than environmental fluctuations have been detected across major fault structures, at distances of more than 1 mile from the pumping well, and with limited pre-pumping and recovery data at sites across the United States. In addition to water-level modeling, utilities exist in SeriesSEE for viewing, cleaning, manipulating, and analyzing time-series data.

  6. A statistical method linking geological and historical eruption time series for volcanic hazard estimations: Applications to active polygenetic volcanoes

    Science.gov (United States)

    Mendoza-Rosas, Ana Teresa; De la Cruz-Reyna, Servando

    2008-09-01

    The probabilistic analysis of volcanic eruption time series is an essential step for the assessment of volcanic hazard and risk. Such series describe complex processes involving different types of eruptions over different time scales. A statistical method linking geological and historical eruption time series is proposed for calculating the probabilities of future eruptions. The first step of the analysis is to characterize the eruptions by their magnitudes. As is the case in most natural phenomena, lower magnitude events are more frequent, and the behavior of the eruption series may be biased by such events. On the other hand, eruptive series are commonly studied using conventional statistics and treated as homogeneous Poisson processes. However, time-dependent series, or sequences including rare or extreme events, represented by very few data of large eruptions require special methods of analysis, such as the extreme-value theory applied to non-homogeneous Poisson processes. Here we propose a general methodology for analyzing such processes attempting to obtain better estimates of the volcanic hazard. This is done in three steps: Firstly, the historical eruptive series is complemented with the available geological eruption data. The linking of these series is done assuming an inverse relationship between the eruption magnitudes and the occurrence rate of each magnitude class. Secondly, we perform a Weibull analysis of the distribution of repose time between successive eruptions. Thirdly, the linked eruption series are analyzed as a non-homogeneous Poisson process with a generalized Pareto distribution as intensity function. As an application, the method is tested on the eruption series of five active polygenetic Mexican volcanoes: Colima, Citlaltépetl, Nevado de Toluca, Popocatépetl and El Chichón, to obtain hazard estimates.

  7. La ciencia en la vida actual. Volumen II. Edicion para el maestro (Science in Everyday Life. Volume II. Teacher Edition). Applied Basic Curriculum Series.

    Science.gov (United States)

    Evaluation, Dissemination and Assessment Center, Dallas.

    This guide, the second in a series of three, provides the Spanish-speaking intermediate science student and teacher an opportunity to review selected science concepts and processes through activities which emphasize the applicability of scientific knowledge in the professional world. This guide is divided into three components. The first component…

  8. La ciencia en la vida actual. Volumen I. Edicion para el maestro (Science in Everyday Life. Volume I. Teacher Edition). Applied Basic Curriculum Series.

    Science.gov (United States)

    Evaluation, Dissemination and Assessment Center, Dallas.

    This guide, the first in a series of three, provides the Spanish-speaking intermediate science student and teacher an opportunity to review selected science concepts and processes through activities which emphasize the applicability of scientific knowledge in the professional world. The three components in this guide deal with (1) ecology (what…

  9. La ciencia en la vida actual. Volumen III. Edicion para el maestro (Science in Everyday Life. Volume III. Teacher Edition). Applied Basic Curriculum Series.

    Science.gov (United States)

    Evaluation, Dissemination and Assessment Center, Dallas.

    This guide, the third in a series of three, provides the Spanish-speaking intermediate science student and teacher an opportunity to review selected science concepts and processes through activities which emphasize the applicability of scientific knowledge in the professional world. The three components in this guide deal with (1) the scientific…

  10. Characterizing and estimating noise in InSAR and InSAR time series with MODIS

    Science.gov (United States)

    Barnhart, William D.; Lohman, Rowena B.

    2013-01-01

    InSAR time series analysis is increasingly used to image subcentimeter displacement rates of the ground surface. The precision of InSAR observations is often affected by several noise sources, including spatially correlated noise from the turbulent atmosphere. Under ideal scenarios, InSAR time series techniques can substantially mitigate these effects; however, in practice the temporal distribution of InSAR acquisitions over much of the world exhibit seasonal biases, long temporal gaps, and insufficient acquisitions to confidently obtain the precisions desired for tectonic research. Here, we introduce a technique for constraining the magnitude of errors expected from atmospheric phase delays on the ground displacement rates inferred from an InSAR time series using independent observations of precipitable water vapor from MODIS. We implement a Monte Carlo error estimation technique based on multiple (100+) MODIS-based time series that sample date ranges close to the acquisitions times of the available SAR imagery. This stochastic approach allows evaluation of the significance of signals present in the final time series product, in particular their correlation with topography and seasonality. We find that topographically correlated noise in individual interferograms is not spatially stationary, even over short-spatial scales (<10 km). Overall, MODIS-inferred displacements and velocities exhibit errors of similar magnitude to the variability within an InSAR time series. We examine the MODIS-based confidence bounds in regions with a range of inferred displacement rates, and find we are capable of resolving velocities as low as 1.5 mm/yr with uncertainties increasing to ∼6 mm/yr in regions with higher topographic relief.

  11. Strategies for Estimating Teacher Supply and Demand Using Student and Teacher Data. REL 2017-197

    Science.gov (United States)

    Lindsay, Jim; Wan, Yinmei; Berg-Jacobson, Alexander; Walston, Jill; Redford, Jeremy

    2016-01-01

    Every year the U.S. Department of Education reports for each state in the country the grade levels, subject areas, and geographic areas that have experienced teacher shortages (U.S. Department of Education, Office of Postsecondary Education, 2015). A teacher shortage occurs when the number of teachers available in a specific grade, subject matter…

  12. Using Technology for Geography Teacher Education: Web-Based Professional Development

    Science.gov (United States)

    Frazier, Cheryl A.; Boehm, Richard G.

    2012-01-01

    This qualitative study explores the perceived value of a video-based online workshop in Geography, "Watershed Management," part of the Geography: Teaching with the Stars series, a 22 program professional development series for teachers of geography, social studies, and environmental science. Results indicated that teachers reported…

  13. Classification of Living Things. A Teacher's Manual for General Level Program Development. Grades 7 and 8. Science and Society Teaching Units. Informal Series/55.

    Science.gov (United States)

    Roberts, Douglas A.; And Others

    This manual is one of a series designed to assist junior high school teachers in developing general level or non-academic science programs which focus on the relationship between science and society. Although designed primarily for grades 7 and 8, the content is also suitable for students in grade 6. The major portion of the manual consists of six…

  14. Teacher Morale, Motivation and Professional Identity: Insight for Educational Policymakers from State Teachers of the Year. Teacher Researcher Policy Paper Series

    Science.gov (United States)

    Bosso, David

    2017-01-01

    Informed by a qualitative study involving 24 individuals, each of whom has been recognized as a State Teacher of the Year, this report presents an exploration of the phenomena of teacher morale, motivation and perceptions of job satisfaction as related to professional identity and professional growth in the context of educational change. The…

  15. Does Teacher Preparation Matter? Evidence about Teacher Certification, Teach for America, and Teacher Effectiveness.

    Directory of Open Access Journals (Sweden)

    Linda Darling-Hammond

    2005-10-01

    Full Text Available Recent debates about the utility of teacher education have raised questions about whether certified teachers are, in general, more effective than those who have not met the testing and training requirements for certification, and whether some candidates with strong liberal arts backgrounds might be at least as effective as teacher education graduates. This study examines these questions with a large student-level data set from Houston, Texas that links student characteristics and achievement with data about their teachers' certification status, experience, and degree levels from 1995-2002. The data set also allows an examination of whether Teach for America (TFA candidates-recruits from selective universities who receive a few weeks of training before they begin teaching-are as effective as similarly experienced certified teachers. In a series of regression analyses looking at 4th and 5th grade student achievement gains on six different reading and mathematics tests over a six-year period, we find that certified teachers consistently produce stronger student achievement gains than do uncertified teachers. These findings hold for TFA recruits as well as others. Controlling for teacher experience, degrees, and student characteristics, uncertified TFA recruits are less effective than certified teachers, and perform about as well as other uncertified teachers. TFA recruits who become certified after 2 or 3 years do about as well as other certified teachers in supporting student achievement gains; however, nearly all of them leave within three years. Teachers' effectiveness appears strongly related to the preparation they have received for teaching.

  16. Supporting French Teachers for a Paradigm Shift in Grammar Education: A Teacher Trainer's Perspective

    Science.gov (United States)

    Thibeault, Joël

    2016-01-01

    This article presents a series of pedagogical workshops that was offered over two years to a cohort of 50 teachers practising in Ontarian French schools. Focusing on grammar teaching, the workshops' objectives were to: (a) contribute to the teachers' development of linguistic knowledge consistent with the grammar under new provincial standards and…

  17. Parameter estimation methods for gene circuit modeling from time-series mRNA data: a comparative study.

    Science.gov (United States)

    Fan, Ming; Kuwahara, Hiroyuki; Wang, Xiaolei; Wang, Suojin; Gao, Xin

    2015-11-01

    Parameter estimation is a challenging computational problem in the reverse engineering of biological systems. Because advances in biotechnology have facilitated wide availability of time-series gene expression data, systematic parameter estimation of gene circuit models from such time-series mRNA data has become an important method for quantitatively dissecting the regulation of gene expression. By focusing on the modeling of gene circuits, we examine here the performance of three types of state-of-the-art parameter estimation methods: population-based methods, online methods and model-decomposition-based methods. Our results show that certain population-based methods are able to generate high-quality parameter solutions. The performance of these methods, however, is heavily dependent on the size of the parameter search space, and their computational requirements substantially increase as the size of the search space increases. In comparison, online methods and model decomposition-based methods are computationally faster alternatives and are less dependent on the size of the search space. Among other things, our results show that a hybrid approach that augments computationally fast methods with local search as a subsequent refinement procedure can substantially increase the quality of their parameter estimates to the level on par with the best solution obtained from the population-based methods while maintaining high computational speed. These suggest that such hybrid methods can be a promising alternative to the more commonly used population-based methods for parameter estimation of gene circuit models when limited prior knowledge about the underlying regulatory mechanisms makes the size of the parameter search space vastly large. © The Author 2015. Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

  18. Motivation of Teachers. ACSA School Management Digest, Series 1, Number 18. ERIC/CEM Research Analysis Series, Number 46.

    Science.gov (United States)

    Thompson, Sydney

    This publication discusses intrinsic teacher motivation by reviewing human resources literature and making use of educational literature and interviews with working educators. First it provides sketches of the work motivation theories of McGregor, Maslow, Herzberg, and Deci. Next, the paper examines the work and problems of teachers. Finally, it…

  19. Environmental Kuznets revisited. Time-series versus panel estimation. The CO2-case

    International Nuclear Information System (INIS)

    Dijkgraaf, E.; Vollebergh, H.R.J.

    1998-01-01

    According to the Environmental Kuznets Curve (EKC) hypothesis economic growth and improving environmental quality are compatible. An inverted U-shaped relationship would exist between economic performance and environmental quality suggesting that after some threshold a growing economy would cause smaller pollution. Usually the EKC hypothesis is tested for pooled panel data of some (sub)set of environmental indicators and GDP. The essential assumption behind pooling the observations of different countries in one panel is that the outcome of the economic process would be the same for all countries with respect to emissions. That is, the curvature of the Income-Emission Relation (IER) is the same for the pooled countries as far as they have the same GDP range. In our study we show this methodology to be misleading for at least the special case of carbon dioxide (CO2) emissions and the GDP level. Using OECD-wide data from 1960 to 1990, we find that the pooled estimation results show positive auto-correlation. Other studies correct for this problem. However, as we show, it seems more likely that the estimated regression model is not correct due to the pooling of the country observations. Testing the model per country reveals that the IER is very different for countries. While some countries show growing carbon dioxide emissions per capita with increasing income, others show a stabilizing pattern or even an EKC. This indicates that estimations based on pooling techniques can bias the conclusion about the true IER leading to unjustified inferences on the existence of the EKC. Extending the basic model may result in the justification of pooling. However, our estimations including country specific variables, like population density, openness of the economy and the availability of own fuel sources (endowment effects), do not make us optimistic. The autocorrelation problem remains. If a more general model can not be found the only remaining conclusion is that testing the EKC

  20. Design of Passive Power Filter for Hybrid Series Active Power Filter using Estimation, Detection and Classification Method

    Science.gov (United States)

    Swain, Sushree Diptimayee; Ray, Pravat Kumar; Mohanty, K. B.

    2016-06-01

    This research paper discover the design of a shunt Passive Power Filter (PPF) in Hybrid Series Active Power Filter (HSAPF) that employs a novel analytic methodology which is superior than FFT analysis. This novel approach consists of the estimation, detection and classification of the signals. The proposed method is applied to estimate, detect and classify the power quality (PQ) disturbance such as harmonics. This proposed work deals with three methods: the harmonic detection through wavelet transform method, the harmonic estimation by Kalman Filter algorithm and harmonic classification by decision tree method. From different type of mother wavelets in wavelet transform method, the db8 is selected as suitable mother wavelet because of its potency on transient response and crouched oscillation at frequency domain. In harmonic compensation process, the detected harmonic is compensated through Hybrid Series Active Power Filter (HSAPF) based on Instantaneous Reactive Power Theory (IRPT). The efficacy of the proposed method is verified in MATLAB/SIMULINK domain and as well as with an experimental set up. The obtained results confirm the superiority of the proposed methodology than FFT analysis. This newly proposed PPF is used to make the conventional HSAPF more robust and stable.

  1. The Mythmaker of Seneca. Report Series 2.13.

    Science.gov (United States)

    Quick, Doris M.

    This portrait of a high school literature classroom is one of a series of several such portraits which depict diverse classroom settings of high school literature, and which result from the second year of a teacher-research project in the greater Albany, New York area. This article portrays teacher Mr. McCabe and his eighth grade class in their…

  2. The linguistically aware teacher and the teacher-aware linguist.

    Science.gov (United States)

    McCartney, Elspeth; Ellis, Sue

    2013-07-01

    This review evaluates issues of teacher linguistic knowledge relating to their work with children with speech, language and communication difficulties (SLCD). Information is from Ellis and McCartney [(2011a). Applied linguistics and primary school teaching. Cambridge: Cambridge University Press], a state-of-the-art text deriving from a British Association of Applied Linguistics/Cambridge University Press expert seminar series that details: linguistic research underpinning primary school curricula and pedagogy; the form of linguistic knowledge useful for teachers supporting children with SLCD in partnership with speech and language therapists; and how and when teachers acquire and learn to apply such knowledge. Critical analysis of the options presented for teacher learning indicate that policy enjoinders now include linguistic application as an expected part of teachers' professional knowledge, for all children including those with SLCD, but there is a large unmet learning need. It is concluded that there is a role for clinical linguists to disseminate useable knowledge to teachers in an accessible format. Ways of achieving this are considered.

  3. Estimation of vegetation cover resilience from satellite time series

    Directory of Open Access Journals (Sweden)

    T. Simoniello

    2008-07-01

    Full Text Available Resilience is a fundamental concept for understanding vegetation as a dynamic component of the climate system. It expresses the ability of ecosystems to tolerate disturbances and to recover their initial state. Recovery times are basic parameters of the vegetation's response to forcing and, therefore, are essential for describing realistic vegetation within dynamical models. Healthy vegetation tends to rapidly recover from shock and to persist in growth and expansion. On the contrary, climatic and anthropic stress can reduce resilience thus favouring persistent decrease in vegetation activity.

    In order to characterize resilience, we analyzed the time series 1982–2003 of 8 km GIMMS AVHRR-NDVI maps of the Italian territory. Persistence probability of negative and positive trends was estimated according to the vegetation cover class, altitude, and climate. Generally, mean recovery times from negative trends were shorter than those estimated for positive trends, as expected for vegetation of healthy status. Some signatures of inefficient resilience were found in high-level mountainous areas and in the Mediterranean sub-tropical ones. This analysis was refined by aggregating pixels according to phenology. This multitemporal clustering synthesized information on vegetation cover, climate, and orography rather well. The consequent persistence estimations confirmed and detailed hints obtained from the previous analyses. Under the same climatic regime, different vegetation resilience levels were found. In particular, within the Mediterranean sub-tropical climate, clustering was able to identify features with different persistence levels in areas that are liable to different levels of anthropic pressure. Moreover, it was capable of enhancing reduced vegetation resilience also in the southern areas under Warm Temperate sub-continental climate. The general consistency of the obtained results showed that, with the help of suited analysis

  4. Teacher Leaders: Transforming Schools from the inside. Occasional Paper Series 23

    Science.gov (United States)

    Schmerler, Gil, Ed.; Mhatre, Nayantara; Stacy, Jill; Patrizio, Kami; Winkler, Jessica Endlich; Groves, Jennifer; Rockwood, Kathleen Dickinson; Lin, Clara E.; Hernandez, Lillian; Solorza, Cristian; Hummel, Robin E.

    2009-01-01

    Teacher leadership is "hard." Many of the reasons are obvious: Teaching is a highly labor-intensive profession to begin with, leaving little downtime for work with other adults. School schedules are notoriously stingy with space for adult collaboration. Teachers are rarely paid to exercise leadership; when they are, they are never paid…

  5. Interior Design: Teacher's Instructional Guide.

    Science.gov (United States)

    Hays, Tricia

    This teacher's instructional guide, which is part of a family and consumer sciences education series focusing on a broad range of employment opportunities, is intended to assist teachers responsible for teaching one- and two-year interior design programs for Texas high school students. The following are among the items included: (1) introductory…

  6. Parameter estimation methods for gene circuit modeling from time-series mRNA data: a comparative study

    KAUST Repository

    Fan, M.

    2015-03-29

    Parameter estimation is a challenging computational problemin the reverse engineering of biological systems. Because advances in biotechnology have facilitated wide availability of time-series gene expression data, systematic parameter esti- mation of gene circuitmodels fromsuch time-series mRNA data has become an importantmethod for quantitatively dissecting the regulation of gene expression. By focusing on themodeling of gene circuits, we examine here the perform- ance of three types of state-of-the-art parameter estimation methods: population-basedmethods, onlinemethods and model-decomposition-basedmethods. Our results show that certain population-basedmethods are able to generate high- quality parameter solutions. The performance of thesemethods, however, is heavily dependent on the size of the param- eter search space, and their computational requirements substantially increase as the size of the search space increases. In comparison, onlinemethods andmodel decomposition-basedmethods are computationally faster alternatives and are less dependent on the size of the search space. Among other things, our results show that a hybrid approach that augments computationally fastmethods with local search as a subsequent refinement procedure can substantially increase the qual- ity of their parameter estimates to the level on par with the best solution obtained fromthe population-basedmethods whilemaintaining high computational speed. These suggest that such hybridmethods can be a promising alternative to themore commonly used population-basedmethods for parameter estimation of gene circuit models when limited prior knowledge about the underlying regulatorymechanismsmakes the size of the parameter search space vastly large. © The Author 2015. Published by Oxford University Press.

  7. Examining teacher self-efficacy about best practices in science during a professional development series

    Science.gov (United States)

    Menez, Jessica L.

    Using extant data that were collected as part of a larger project, the current study examined teacher self-efficacy and the teachers' intentions to implement workshop content throughout the course of a six-week professional development workshop focused on enhancing science motivation for students through the adoption of specific instructional strategies. There were a total of 20 middle and high school teacher participants. Results indicated teacher self-efficacy changed significantly from pre to post. Teachers showed higher teacher self-efficacy after the professional development, in particular for influencing student engagement. In addition, we found a moderate correlation between the level of confidence after the implementation of a strategy and teachers intention of trying the strategy again. Finally, new direction for future research topics made possible by this study are presented.

  8. Estimating sediment and caesium-137 fluxes in the Ribble Estuary through time-series airborne remote sensing

    International Nuclear Information System (INIS)

    Wakefield, R.; Tyler, A.N.; McDonald, P.; Atkin, P.A.; Gleizon, P.; Gilvear, D.

    2011-01-01

    High spatial and temporal resolution airborne imagery were acquired for the Ribble Estuary, North West England in 1997 and 2003, to assess the application of time-series airborne remote sensing to quantify total suspended sediment and radionuclide fluxes during a flood and ebb tide sequence. Concomitant measurements of suspended particulate matter (SPM) and water column turbidity were obtained during the time-series image acquisition for the flood and ebb tide sequence on the 17th July 2003 to verify the assumption of a vertically well mixed estuary and thus justifying the vertical extrapolation of spatially integrated estimate of surface SPM. The 137 Cs activity concentrations were calculated from a relatively stable relationship between SPM and 137 Cs for the Ribble Estuary. Total estuary wide budgets of sediment and 137 Cs were obtained by combining the image-derived estimates of surface SPM and 137 Cs with estimates of water volume from a two-dimensional hydrodynamic model (VERSE) developed for the Ribble Estuary. These indicate that around 10,000 tonnes of sediment and 2.72 GBq of 137 Cs were deposited over the tidal sequence monitored in July 2003. This compared favourably with bed height elevation change estimated from field work. An uncertainty analysis on the total sediment and 137 Cs flux yielded a total budget of the order of 40% on the final estimate. The results represent a novel approach to providing a spatially integrated estimate of the total net sediment and radionuclide flux in an intertidal environment over a flood and ebb tide sequence. - Research highlights: → This paper provides a rare insight into the next flux of sediment and associated radionuclide loading into an estuary over and ebb and flood tide sequence. → The paper uses high temporal resolution airborne imagery coupled with concomitant sampling to convert total suspended sediment flux to 137 Cs loading. → For the estuary and date studied, it is estimate that an 10,000 tonnes of

  9. Integrating field plots, lidar, and landsat time series to provide temporally consistent annual estimates of biomass from 1990 to present

    Science.gov (United States)

    Warren B. Cohen; Hans-Erik Andersen; Sean P. Healey; Gretchen G. Moisen; Todd A. Schroeder; Christopher W. Woodall; Grant M. Domke; Zhiqiang Yang; Robert E. Kennedy; Stephen V. Stehman; Curtis Woodcock; Jim Vogelmann; Zhe Zhu; Chengquan. Huang

    2015-01-01

    We are developing a system that provides temporally consistent biomass estimates for national greenhouse gas inventory reporting to the United Nations Framework Convention on Climate Change. Our model-assisted estimation framework relies on remote sensing to scale from plot measurements to lidar strip samples, to Landsat time series-based maps. As a demonstration, new...

  10. A combined method to estimate parameters of the thalamocortical model from a heavily noise-corrupted time series of action potential

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ruofan; Wang, Jiang; Deng, Bin, E-mail: dengbin@tju.edu.cn; Liu, Chen; Wei, Xile [Department of Electrical and Automation Engineering, Tianjin University, Tianjin (China); Tsang, K. M.; Chan, W. L. [Department of Electrical Engineering, The Hong Kong Polytechnic University, Kowloon (Hong Kong)

    2014-03-15

    A combined method composing of the unscented Kalman filter (UKF) and the synchronization-based method is proposed for estimating electrophysiological variables and parameters of a thalamocortical (TC) neuron model, which is commonly used for studying Parkinson's disease for its relay role of connecting the basal ganglia and the cortex. In this work, we take into account the condition when only the time series of action potential with heavy noise are available. Numerical results demonstrate that not only this method can estimate model parameters from the extracted time series of action potential successfully but also the effect of its estimation is much better than the only use of the UKF or synchronization-based method, with a higher accuracy and a better robustness against noise, especially under the severe noise conditions. Considering the rather important role of TC neuron in the normal and pathological brain functions, the exploration of the method to estimate the critical parameters could have important implications for the study of its nonlinear dynamics and further treatment of Parkinson's disease.

  11. A combined method to estimate parameters of the thalamocortical model from a heavily noise-corrupted time series of action potential

    International Nuclear Information System (INIS)

    Wang, Ruofan; Wang, Jiang; Deng, Bin; Liu, Chen; Wei, Xile; Tsang, K. M.; Chan, W. L.

    2014-01-01

    A combined method composing of the unscented Kalman filter (UKF) and the synchronization-based method is proposed for estimating electrophysiological variables and parameters of a thalamocortical (TC) neuron model, which is commonly used for studying Parkinson's disease for its relay role of connecting the basal ganglia and the cortex. In this work, we take into account the condition when only the time series of action potential with heavy noise are available. Numerical results demonstrate that not only this method can estimate model parameters from the extracted time series of action potential successfully but also the effect of its estimation is much better than the only use of the UKF or synchronization-based method, with a higher accuracy and a better robustness against noise, especially under the severe noise conditions. Considering the rather important role of TC neuron in the normal and pathological brain functions, the exploration of the method to estimate the critical parameters could have important implications for the study of its nonlinear dynamics and further treatment of Parkinson's disease

  12. A combined method to estimate parameters of the thalamocortical model from a heavily noise-corrupted time series of action potential

    Science.gov (United States)

    Wang, Ruofan; Wang, Jiang; Deng, Bin; Liu, Chen; Wei, Xile; Tsang, K. M.; Chan, W. L.

    2014-03-01

    A combined method composing of the unscented Kalman filter (UKF) and the synchronization-based method is proposed for estimating electrophysiological variables and parameters of a thalamocortical (TC) neuron model, which is commonly used for studying Parkinson's disease for its relay role of connecting the basal ganglia and the cortex. In this work, we take into account the condition when only the time series of action potential with heavy noise are available. Numerical results demonstrate that not only this method can estimate model parameters from the extracted time series of action potential successfully but also the effect of its estimation is much better than the only use of the UKF or synchronization-based method, with a higher accuracy and a better robustness against noise, especially under the severe noise conditions. Considering the rather important role of TC neuron in the normal and pathological brain functions, the exploration of the method to estimate the critical parameters could have important implications for the study of its nonlinear dynamics and further treatment of Parkinson's disease.

  13. How Technology Teachers Understand Technological Knowledge

    Science.gov (United States)

    Norström, Per

    2014-01-01

    Swedish technology teachers' views of technological knowledge are examined through a written survey and a series of interviews. The study indicates that technology teachers' understandings of what constitutes technological knowledge and how it is justified vary considerably. The philosophical discussions on the topic are unknown to them. This lack…

  14. Index to the Understanding the Atom Series

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-01-01

    The U. S. Atomic Energy Commission publishes the Understanding the Atom Series of educational booklets for high school science students and their teachers. This series explains many aspects of nuclear science including its history and applications. Because these 51 booklets cover such a variety of scientific fields, this index was prepared to help the reader find quickly those booklets that contain the information he needs.

  15. Planning Together: Positive Classroom Environments. Diversity in the Classroom Series, Number Four.

    Science.gov (United States)

    Hindle, Doug

    This document, the fourth in a series on diversity in the classroom, supports the belief that challenges faced by teachers working with diverse students can only be met through teacher practices that increase levels of positive teacher-student interaction and that create, in each student, effective social and problem solving skills. Section 1,…

  16. Child-to-Teacher Ratio and Day Care Teacher Sickeness Absenteeism

    DEFF Research Database (Denmark)

    Gørtz, Mette; Andersson, Elvira

    2014-01-01

    time periods, 2002–2003 and 2005–2006, by using generalized method of moments with lagged levels of the child-to-teacher ratio as instrument. Our estimation results are somewhat mixed. Generally, the results indicate that the child-to-teacher ratio is positively related to short-term sickness absence...

  17. Estimating and Analyzing Savannah Phenology with a Lagged Time Series Model

    DEFF Research Database (Denmark)

    Boke-Olen, Niklas; Lehsten, Veiko; Ardo, Jonas

    2016-01-01

    cycle due to their areal coverage and can have an effect on the food security in regions that depend on subsistence farming. In this study we investigate how soil moisture, mean annual precipitation, and day length control savannah phenology by developing a lagged time series model. The model uses...... climate data for 15 flux tower sites across four continents, and normalized difference vegetation index from satellite to optimize a statistical phenological model. We show that all three variables can be used to estimate savannah phenology on a global scale. However, it was not possible to create...... a simplified savannah model that works equally well for all sites on the global scale without inclusion of more site specific parameters. The simplified model showed no bias towards tree cover or between continents and resulted in a cross-validated r2 of 0.6 and root mean squared error of 0.1. We therefore...

  18. Bureaucracy and Teachers' Sense of Power

    OpenAIRE

    YuÌ cel, Cemil

    1999-01-01

    The purpose of this study was to explore the utility of Hall's (1961) conceptualization of Max Weber's (1946) theory of bureaucracy as an analytical tool in Turkey. The population was 1946 teachers in 91 public schools that employ five or more teachers. The instruments were distributed to 725 teachers in 68 schools in Karabuk province. Useable returns were 486. A pilot sample (one third of the useable returns) was generated to test the instruments by utilizing a series of item analyses. Remai...

  19. Taylor-series and Monte-Carlo-method uncertainty estimation of the width of a probability distribution based on varying bias and random error

    International Nuclear Information System (INIS)

    Wilson, Brandon M; Smith, Barton L

    2013-01-01

    Uncertainties are typically assumed to be constant or a linear function of the measured value; however, this is generally not true. Particle image velocimetry (PIV) is one example of a measurement technique that has highly nonlinear, time varying local uncertainties. Traditional uncertainty methods are not adequate for the estimation of the uncertainty of measurement statistics (mean and variance) in the presence of nonlinear, time varying errors. Propagation of instantaneous uncertainty estimates into measured statistics is performed allowing accurate uncertainty quantification of time-mean and statistics of measurements such as PIV. It is shown that random errors will always elevate the measured variance, and thus turbulent statistics such as u'u'-bar. Within this paper, nonlinear, time varying errors are propagated from instantaneous measurements into the measured mean and variance using the Taylor-series method. With these results and knowledge of the systematic and random uncertainty of each measurement, the uncertainty of the time-mean, the variance and covariance can be found. Applicability of the Taylor-series uncertainty equations to time varying systematic and random errors and asymmetric error distributions are demonstrated with Monte-Carlo simulations. The Taylor-series uncertainty estimates are always accurate for uncertainties on the mean quantity. The Taylor-series variance uncertainty is similar to the Monte-Carlo results for cases in which asymmetric random errors exist or the magnitude of the instantaneous variations in the random and systematic errors is near the ‘true’ variance. However, the Taylor-series method overpredicts the uncertainty in the variance as the instantaneous variations of systematic errors are large or are on the same order of magnitude as the ‘true’ variance. (paper)

  20. Introduction to Financial Services. Teacher Edition. Financial Services Series.

    Science.gov (United States)

    Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    This document contains teacher's materials for a course designed for 11th- and 12th-grade students who are interested in pursuing a career in financial institutions. The course consists of six instructional units: orientation, personal money management, the wise use of credit, negotiable instruments, communications, and security. Depending on the…

  1. Going to the Market. Teacher Edition. Fashion Buying Series.

    Science.gov (United States)

    Collins, Cindy

    This teacher's guide presents material for a unit on attending the retail fashion market. Content focuses on previewing merchandise for purchase, factors involved in a major market trip, common terms used when ordering merchandise, and pricing strategies. The guide contains 4 objectives, 6 group learning activities keyed to the objectives, 12…

  2. Introduction to Fashion Buying. Teacher Edition. Fashion Buying Series.

    Science.gov (United States)

    Collins, Cindy

    This teacher's guide presents material for a unit on introduction to fashion buying. Content focuses on information sources, retail store types, the responsibilities of a buyer, and the qualifications of a buyer. The guide contains 4 objectives, 4 group learning activities keyed to the objectives, 17 transparency masters with dialogue for each,…

  3. Estimating a Smooth Common Transfer Function with a Panel of Time Series - Inflow of Larvae Cod as an Example

    Directory of Open Access Journals (Sweden)

    Elizabeth Hansen

    2012-07-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman","serif";} The annual response variable in an ecological monitoring study often relates linearly to the weighted cumulative effect of some daily covariate, after adjusting for other annual covariates. Here we consider the problem of non-parametrically estimating the weights involved in computing the aforementioned cumulative effect, with a panel of short and contemporaneously correlated time series whose responses share the common cumulative effect of a daily covariate. The sequence of (unknown daily weights constitutes the so-called transfer function. Specifically, we consider the problem of estimating a smooth common transfer function shared by a panel of short time series that are contemporaneously correlated. We propose an estimation scheme using a likelihood approach that penalizes the roughness of the common transfer function. We illustrate the proposed method with a simulation study and a biological example of indirectly estimating the spawning date distribution of North Sea cod.

  4. A time series deformation estimation in the NW Himalayas using SBAS InSAR technique

    Science.gov (United States)

    Kumar, V.; Venkataraman, G.

    2012-12-01

    A time series land deformation studies in north western Himalayan region has been presented in this study. Synthetic aperture radar (SAR) interferometry (InSAR) is an important tool for measuring the land displacement caused by different geological processes [1]. Frequent spatial and temporal decorrelation in the Himalayan region is a strong impediment in precise deformation estimation using conventional interferometric SAR approach. In such cases, advanced DInSAR approaches PSInSAR as well as Small base line subset (SBAS) can be used to estimate earth surface deformation. The SBAS technique [2] is a DInSAR approach which uses a twelve or more number of repeat SAR acquisitions in different combinations of a properly chosen data (subsets) for generation of DInSAR interferograms using two pass interferometric approach. Finally it leads to the generation of mean deformation velocity maps and displacement time series. Herein, SBAS algorithm has been used for time series deformation estimation in the NW Himalayan region. ENVISAT ASAR IS2 swath data from 2003 to 2008 have been used for quantifying slow deformation. Himalayan region is a very active tectonic belt and active orogeny play a significant role in land deformation process [3]. Geomorphology in the region is unique and reacts to the climate change adversely bringing with land slides and subsidence. Settlements on the hill slopes are prone to land slides, landslips, rockslides and soil creep. These hazardous features have hampered the over all progress of the region as they obstruct the roads and flow of traffic, break communication, block flowing water in stream and create temporary reservoirs and also bring down lot of soil cover and thus add enormous silt and gravel to the streams. It has been observed that average deformation varies from -30.0 mm/year to 10 mm/year in the NW Himalayan region . References [1] Massonnet, D., Feigl, K.L.,Rossi, M. and Adragna, F. (1994) Radar interferometry mapping of

  5. Preparing for the Market. Teacher Edition. Fashion Buying Series.

    Science.gov (United States)

    Collins, Cindy

    This teacher's guide presents material for a unit on preparing for the retail fashion market. Content focuses on merchandise plans, computing open-to-buy, computing turnover, the components of a model stock plan, and criteria used when selecting a supplier. The guide contains 5 objectives, 6 group learning activities keyed to the objectives, 21…

  6. Classroom Management. TESOL Classroom Practice Series

    Science.gov (United States)

    Farrell, Thomas S. C., Ed.

    2008-01-01

    This series captures the dynamics of the contemporary ESOL classroom. It showcases state-of-the-art curricula, materials, tasks, and activities reflecting emerging trends in language education and seeks to build localized language teaching and learning theories based on teachers' and students' unique experiences in and beyond the classroom. Each…

  7. Co-operation Between Science Teachers and Mathematics Teachers. Volumes 1-6.

    Science.gov (United States)

    Rogerson, Alan, Ed.

    This document contains six separate works, titled: (1) Functions and Physics; (2) Links Between Geography and Mathematics; (3) Our Inheritance: Common Ground for the Mathematics and Biology Teacher; (4) Mathematics and Chemistry: The Classroom Interface; (5) Mathematical Modeling; and (6) Mathematical Modeling with Calculus. This series of…

  8. Great to Influential: Teacher Leaders' Roles in Supporting Instruction

    Science.gov (United States)

    Jacques, Catherine; Weber, Gretchen; Bosso, David; Olson, Derek; Bassett, Katherine

    2016-01-01

    This report is the second in a series from a collaboration of nine leading organizations working to advance teaching and elevate the profession. For years, education leaders have sought to pinpoint how teachers become effective in order to better leverage teachers' impact on student learning and improve student outcomes. Teacher leadership is…

  9. Melinda: De Facto Primary School Music Teacher

    Science.gov (United States)

    de Vries, Peter

    2013-01-01

    A series of reviews dating back to the 1960s and a body of research literature points to the inadequate delivery of music education by generalist primary school teachers in Australian schools. Despite recommendations for specialist music teachers to teach music in all Australian primary schools to counter this ongoing trend, such an approach has…

  10. Estimating High-Dimensional Time Series Models

    DEFF Research Database (Denmark)

    Medeiros, Marcelo C.; Mendes, Eduardo F.

    We study the asymptotic properties of the Adaptive LASSO (adaLASSO) in sparse, high-dimensional, linear time-series models. We assume both the number of covariates in the model and candidate variables can increase with the number of observations and the number of candidate variables is, possibly......, larger than the number of observations. We show the adaLASSO consistently chooses the relevant variables as the number of observations increases (model selection consistency), and has the oracle property, even when the errors are non-Gaussian and conditionally heteroskedastic. A simulation study shows...

  11. A new time-series methodology for estimating relationships between elderly frailty, remaining life expectancy, and ambient air quality.

    Science.gov (United States)

    Murray, Christian J; Lipfert, Frederick W

    2012-01-01

    Many publications estimate short-term air pollution-mortality risks, but few estimate the associated changes in life-expectancies. We present a new methodology for analyzing time series of health effects, in which prior frailty is assumed to precede short-term elderly nontraumatic mortality. The model is based on a subpopulation of frail individuals whose entries and exits (deaths) are functions of daily and lagged environmental conditions: ambient temperature/season, airborne particles, and ozone. This frail susceptible population is unknown; its fluctuations cannot be observed but are estimated using maximum-likelihood methods with the Kalman filter. We used an existing 14-y set of daily data to illustrate the model and then tested the assumption of prior frailty with a new generalized model that estimates the portion of the daily death count allocated to nonfrail individuals. In this demonstration dataset, new entries into the high-risk pool are associated with lower ambient temperatures and higher concentrations of particulate matter and ozone. Accounting for these effects on antecedent frailty reduces this at-risk population, yielding frail life expectancies of 5-7 days. Associations between environmental factors and entries to the at-risk pool are about twice as strong as for mortality. Nonfrail elderly deaths are seen to make only small contributions. This new model predicts a small short-lived frail population-at-risk that is stable over a wide range of environmental conditions. The predicted effects of pollution on new entries and deaths are robust and consistent with conventional morbidity/mortality times-series studies. We recommend model verification using other suitable datasets.

  12. Estimating Unbiased Land Cover Change Areas In The Colombian Amazon Using Landsat Time Series And Statistical Inference Methods

    Science.gov (United States)

    Arevalo, P. A.; Olofsson, P.; Woodcock, C. E.

    2017-12-01

    Unbiased estimation of the areas of conversion between land categories ("activity data") and their uncertainty is crucial for providing more robust calculations of carbon emissions to the atmosphere, as well as their removals. This is particularly important for the REDD+ mechanism of UNFCCC where an economic compensation is tied to the magnitude and direction of such fluxes. Dense time series of Landsat data and statistical protocols are becoming an integral part of forest monitoring efforts, but there are relatively few studies in the tropics focused on using these methods to advance operational MRV systems (Monitoring, Reporting and Verification). We present the results of a prototype methodology for continuous monitoring and unbiased estimation of activity data that is compliant with the IPCC Approach 3 for representation of land. We used a break detection algorithm (Continuous Change Detection and Classification, CCDC) to fit pixel-level temporal segments to time series of Landsat data in the Colombian Amazon. The segments were classified using a Random Forest classifier to obtain annual maps of land categories between 2001 and 2016. Using these maps, a biannual stratified sampling approach was implemented and unbiased stratified estimators constructed to calculate area estimates with confidence intervals for each of the stable and change classes. Our results provide evidence of a decrease in primary forest as a result of conversion to pastures, as well as increase in secondary forest as pastures are abandoned and the forest allowed to regenerate. Estimating areas of other land transitions proved challenging because of their very small mapped areas compared to stable classes like forest, which corresponds to almost 90% of the study area. Implications on remote sensing data processing, sample allocation and uncertainty reduction are also discussed.

  13. A Dip into the World of Particles for Swedish Teachers

    CERN Multimedia

    2001-01-01

    For three full days, forty-one Swedish secondary school physics teachers were introduced to the rudiments of the particle physics. This series of courses is celebrating its tenth anniversary. The Swedish teachers followed lectures, visited CERN experiments... ... and analysed the latest DELPHI data. 'I am sure that, as in previous years, many of these teachers will return to CERN with their students. It is an excellent way of encouraging young people to orient themselves towards physics.' Staffan Hörnberg, Vice President of the International Centre for Education and Development, is enthusiastic about the repercussions of the teaching programme for Swedish teachers that he organises with CERN physicist, Richard Jacobsson. For the tenth consecutive year, this series of introductory courses to particle physics was a success. Forty-one teachers came from schools all over Sweden to take part in lectures and visits on the theme of particle physics, its methods of investigation, and its applications. San...

  14. Teacher Professional Development in Laredo, TX

    Science.gov (United States)

    Finkelstein, Keely D.; Macri, L. M.; Hemenway, M.; Wetzel, M.; Preston, S.; Rood, M.

    2014-01-01

    In the fall of 2012, McDonald Observatory, Texas A&M University, and Texas A&M International University conducted a series of workshops on astronomy content for 5th - 8th grade teachers in Laredo, Texas. Three one-day workshops were held at the Lamar Bruni Vergara Planetarium of Texas A&M International University, using a mix of in-person and distance learning technology. Texas A&M professor Lucas Macri gave public talks in English and Spanish, and a lunch-time presentation to the teachers. A series of evaluation tools were used to assess the success of the workshops. A Nominal Group Technique (NGT) discussion was used, through which groups developed consensus answers about their learning, expectations for classroom use, and satisfaction with the workshop. The Astronomy/Space Science Test (MOSART Grades 5-8) was also issued as a pre- and post-test to assess gains in knowledge. Teacher consensus was that the materials and activities of the workshop had been helpful for learning and that they expected to use many of them in their classrooms. However, the evaluation also showed that teachers would have preferred the Observatory educator be physically present for all workshops. Past video-conferencing workshops, where local facilitators first participated in workshops at the Observatory, showed better feedback and results concerning this point. Comparing those results to the present case, we conclude that more clearly defined roles and better training for the science specialists and local facilitators would improve the video conference experience for the teachers. Comparison of pre- and post-test results showed improved teacher knowledge. An additional benefit of this project was the further development of partnerships between McDonald Observatory and Texas A&M International University, which has resulted in further education projects, including a video-conference presentation series to eight-grade students and their families. This secondary project focused on

  15. Fuzzy Inference System Approach for Locating Series, Shunt, and Simultaneous Series-Shunt Faults in Double Circuit Transmission Lines.

    Science.gov (United States)

    Swetapadma, Aleena; Yadav, Anamika

    2015-01-01

    Many schemes are reported for shunt fault location estimation, but fault location estimation of series or open conductor faults has not been dealt with so far. The existing numerical relays only detect the open conductor (series) fault and give the indication of the faulty phase(s), but they are unable to locate the series fault. The repair crew needs to patrol the complete line to find the location of series fault. In this paper fuzzy based fault detection/classification and location schemes in time domain are proposed for both series faults, shunt faults, and simultaneous series and shunt faults. The fault simulation studies and fault location algorithm have been developed using Matlab/Simulink. Synchronized phasors of voltage and current signals of both the ends of the line have been used as input to the proposed fuzzy based fault location scheme. Percentage of error in location of series fault is within 1% and shunt fault is 5% for all the tested fault cases. Validation of percentage of error in location estimation is done using Chi square test with both 1% and 5% level of significance.

  16. Arts in the Classroom: What One Elementary Teacher Can Do.

    Science.gov (United States)

    Ambler, Nancy Morison; Strong, Barbara R.

    This monograph, one in a series, describes ways in which elementary teachers have brought arts to the classroom. Descriptions of what teachers are doing are organized by themes. The first theme is the use of the arts in basic skill development. One teacher in Casper, Wyoming, produces rebus books for her students. These books offer a means of…

  17. Developing first time-series of land surface temperature from AATSR with uncertainty estimates

    Science.gov (United States)

    Ghent, Darren; Remedios, John

    2013-04-01

    Land surface temperature (LST) is the radiative skin temperature of the land, and is one of the key parameters in the physics of land-surface processes on regional and global scales. Earth Observation satellites provide the opportunity to obtain global coverage of LST approximately every 3 days or less. One such source of satellite retrieved LST has been the Advanced Along-Track Scanning Radiometer (AATSR); with LST retrieval being implemented in the AATSR Instrument Processing Facility in March 2004. Here we present first regional and global time-series of LST data from AATSR with estimates of uncertainty. Mean changes in temperature over the last decade will be discussed along with regional patterns. Although time-series across all three ATSR missions have previously been constructed (Kogler et al., 2012), the use of low resolution auxiliary data in the retrieval algorithm and non-optimal cloud masking resulted in time-series artefacts. As such, considerable ESA supported development has been carried out on the AATSR data to address these concerns. This includes the integration of high resolution auxiliary data into the retrieval algorithm and subsequent generation of coefficients and tuning parameters, plus the development of an improved cloud mask based on the simulation of clear sky conditions from radiance transfer modelling (Ghent et al., in prep.). Any inference on this LST record is though of limited value without the accompaniment of an uncertainty estimate; wherein the Joint Committee for Guides in Metrology quote an uncertainty as "a parameter associated with the result of a measurement that characterizes the dispersion of the values that could reasonably be attributed to the measurand that is the value of the particular quantity to be measured". Furthermore, pixel level uncertainty fields are a mandatory requirement in the on-going preparation of the LST product for the upcoming Sea and Land Surface Temperature (SLSTR) instrument on-board Sentinel-3

  18. Teacher Satisfaction in Georgia and the Nation: Status and Trends. Teacher Burnout: Causes and Possible Cures. Issues for Education Series.

    Science.gov (United States)

    Georgia Professional Standards Commission, Atlanta.

    Researchers have attributed teacher turnover at both the state and national levels to the high incidence of teacher stress or burnout, a syndrome resulting from a variety of individual, organizational, and societal factors. Burnout involves physical, emotional, and attitudinal exhaustion generated by excessive demands upon the individual's energy,…

  19. SEL/Project Language. Level II, Kindergarten, Teacher's Handbook.

    Science.gov (United States)

    Valladares, Ann E.; Lynch, Helen C.

    The Teacher's Handbook is part of the publication series of the Southeastern Education Laboratory/Project Language (SEL/PL), an 8-year language-centered program designed to alleviate the language deficiencies of disadvantaged children between the ages of four and eleven. For teachers utilizing SEL/PL, the Handbook provides a research summary and…

  20. Ciencias 2. Manual do Professor (Science Teacher's Manual).

    Science.gov (United States)

    Raposo, Lucilia

    This is the teacher's manual for Ciencias 2, the second in a series of elementary science textbooks for Portuguese-speaking students. The student textbook contains 10 chapters and 57 activities. The teacher's manual presents an explanation of the educational goals and the organization of the content, Topics included are environment, the human,…

  1. Stochastic models in the DORIS position time series: estimates for IDS contribution to ITRF2014

    Science.gov (United States)

    Klos, Anna; Bogusz, Janusz; Moreaux, Guilhem

    2017-11-01

    This paper focuses on the investigation of the deterministic and stochastic parts of the Doppler Orbitography and Radiopositioning Integrated by Satellite (DORIS) weekly time series aligned to the newest release of ITRF2014. A set of 90 stations was divided into three groups depending on when the data were collected at an individual station. To reliably describe the DORIS time series, we employed a mathematical model that included the long-term nonlinear signal, linear trend, seasonal oscillations and a stochastic part, all being estimated with maximum likelihood estimation. We proved that the values of the parameters delivered for DORIS data are strictly correlated with the time span of the observations. The quality of the most recent data has significantly improved. Not only did the seasonal amplitudes decrease over the years, but also, and most importantly, the noise level and its type changed significantly. Among several tested models, the power-law process may be chosen as the preferred one for most of the DORIS data. Moreover, the preferred noise model has changed through the years from an autoregressive process to pure power-law noise with few stations characterised by a positive spectral index. For the latest observations, the medians of the velocity errors were equal to 0.3, 0.3 and 0.4 mm/year, respectively, for the North, East and Up components. In the best cases, a velocity uncertainty of DORIS sites of 0.1 mm/year is achievable when the appropriate coloured noise model is taken into consideration.

  2. Comparison of annual maximum series and partial duration series methods for modeling extreme hydrologic events

    DEFF Research Database (Denmark)

    Madsen, Henrik; Rasmussen, Peter F.; Rosbjerg, Dan

    1997-01-01

    Two different models for analyzing extreme hydrologic events, based on, respectively, partial duration series (PDS) and annual maximum series (AMS), are compared. The PDS model assumes a generalized Pareto distribution for modeling threshold exceedances corresponding to a generalized extreme value......). In the case of ML estimation, the PDS model provides the most efficient T-year event estimator. In the cases of MOM and PWM estimation, the PDS model is generally preferable for negative shape parameters, whereas the AMS model yields the most efficient estimator for positive shape parameters. A comparison...... of the considered methods reveals that in general, one should use the PDS model with MOM estimation for negative shape parameters, the PDS model with exponentially distributed exceedances if the shape parameter is close to zero, the AMS model with MOM estimation for moderately positive shape parameters, and the PDS...

  3. Designs for the Evaluation of Teacher Training Materials. Report No. 2.

    Science.gov (United States)

    Okey, James R.; Ciesla, Jerome L.

    This paper describes methods to assess the impact on students of a teacher using skills learned in a training program. Three designs for assessing the effects of teacher training materials are presented: time series design, equivalent time-samples design, and posttest-only control group design. Data obtained by classroom teachers while using the…

  4. Estimating the parameters of globular cluster M 30 (NGC 7099) from time-series photometry

    DEFF Research Database (Denmark)

    Kains, N.; Bramich, D.M.; Figuera Jaimes, R.

    2013-01-01

    Aims. We present the analysis of 26 nights of V and I time-series observations from 2011 and 2012 of the globular cluster M 30 (NGC 7099). We used our data to search for variable stars in this cluster and refine the periods of known variables; we then used our variable star light curves to derive...... values for the cluster's parameters. Methods. We used difference image analysis to reduce our data to obtain high-precision light curves of variable stars. We then estimated the cluster parameters by performing a Fourier decomposition of the light curves of RR Lyrae stars for which a good period estimate...... stars to derive cluster parameters using empirical relations. We find a cluster metallicity [Fe/H]ZW =-2.01 ± 0.04, or [Fe/H]UVES =-2.11 ± 0.06, and a distance of 8.32 ± 0.20 kpc (using RR0 variables), 8.10 kpc (using one RR1 variable), and 8.35 ± 0.42 kpc (using our SX Phoenicis star detection in M 30...

  5. EGARCH: un modelo asimétrico para estimar la volatilidad de series financieras EGARCH: a model to estimate the asymmetric volatility of financial series

    Directory of Open Access Journals (Sweden)

    Horacio Fernández Castaño

    2010-01-01

    Full Text Available En la modelación de las volatilidades con cambios súbitos, es imperativo usar modelos que permitan describir y analizar el dinamismo de la volatilidad, ya que los inversionistas, entre otras cosas, pueden estar interesados en estimar la tasa de retorno y la volatilidad de un instrumento financiero u otros derivados, sólo durante el período de tenencia. En este artículo, que constituye la primera de dos entregas, se hace una evaluación del modelo asimétrico EGARCH que resulta ser muy útil para estudiar la dinámica del Índice General de la Bolsa de valores de Colombia (IGBC y de su volatilidad, pues inicia haciendo una breve revisión del modelo GARCH, resaltando su importancia en la modelación de series de tiempo financieras, e identificando sus debilidades en cuanto a su propiedad de simetría para las distribuciones de colas gruesas y que pueden generar errores de pronóstico. Luego se muestra la importancia del modelo EGARCH para la modelación de algunos hechos que no se logran capturar con los modelos GARCHIn the modeling of volatility with rapid changes, it is imperative to use models to describe and analyze the dynamics of volatility, as investors, among other things, may be interested in estimating the rate of return and volatility of an instrument financial or other derivatives, only during the holding period. This article contains an evaluation of asymmetric EGARCH model that proves to be very useful to study the dynamics of the General Index of the Stock Exchange of Colombia (IGBC and its volatility, since, as will be shown, the results suggest they could be more useful for capture the stylized facts of the Colombian market behavior. It is really significant to evidence the importance of asymmetric models to estimate the volatility of financial series is intended here as a model for identifying, in the best way to estimate the volatility of daily returns of the IGBC.

  6. Listen-Identify-Brainstorm-Reality-Test-Encourage (LIBRE) Problem-Solving Model: Addressing Special Education Teacher Attrition through a Cognitive-Behavioral Approach to Teacher Induction

    Science.gov (United States)

    Guerra, Norma S.; Hernandez, Art; Hector, Alison M.; Crosby, Shane

    2015-01-01

    Special education teacher attrition rates continue to challenge the profession. A cognitive-behavioral problem-solving approach was used to examine three alternative certification program special education teachers' professional development through a series of 41 interviews conducted over a 2-year period. Beginning when they were novice special…

  7. Computer Assisted Instruction in Teacher Education: A Full Length Course.

    Science.gov (United States)

    Cartwright, G. Phillip

    Pennsylvania State University has developed, evaluated, and implemented a series of modules and an entire three-credit teacher education course which is offered completely by microcomputer. The course is entitled "Educating Special Learners." The modules use the Apple II series and the IBM PC series. Evaluation of the course, based on…

  8. Linking Teacher Quality, Student Attendance, and Student Achievement

    Science.gov (United States)

    Gershenson, Seth

    2016-01-01

    Research on the effectiveness of educational inputs, particularly research on teacher effectiveness, typically overlooks teachers' potential impact on behavioral outcomes, such as student attendance. Using longitudinal data on teachers and students in North Carolina I estimate teacher effects on primary school student absences in a value-added…

  9. Understanding Geometric Ideas: Pre-Service Primary Teachers' Knowledge as a Basis for Teaching

    Science.gov (United States)

    Seah, Rebecca

    2015-01-01

    This paper reports part of an ongoing investigation into aspects of pre-service teachers' geometric knowledge. One hundred and fifty-two Australian pre-service teachers responded to a series of questions that reflect the type of knowledge teachers are expected to know and teach. Analysis of their responses shows that teacher knowledge can be…

  10. Estimating extreme dry-spell risk in the Middle Ebro valley (Northeastern Spain). a comparative analysis of partial duration series with a General Pareto distribution and annual maxima series with a Gumbel distribution

    NARCIS (Netherlands)

    Vicente-Serrano, S.; Beguería, S.

    2003-01-01

    This paper analyses fifty-year time series of daily precipitation in a region of the middle Ebro valley (northern Spain) in order to predict extreme dry-spell risk. A comparison of observed and estimated maximum dry spells (50-year return period) showed that the Generalised Pareto (GP)

  11. Technology Acceptance among Pre-Service Teachers: Does Gender Matter?

    Science.gov (United States)

    Teo, Timothy; Fan, Xitao; Du, Jianxia

    2015-01-01

    This study examined possible gender differences in pre-service teachers' perceived acceptance of technology in their professional work under the framework of the technology acceptance model (TAM). Based on a sample of pre-service teachers, a series of progressively more stringent measurement invariance tests (configural, metric, and scalar…

  12. Capturing Structure Implicitly from Time-Series having Limited Data

    OpenAIRE

    Emaasit, Daniel; Johnson, Matthew

    2018-01-01

    Scientific fields such as insider-threat detection and highway-safety planning often lack sufficient amounts of time-series data to estimate statistical models for the purpose of scientific discovery. Moreover, the available limited data are quite noisy. This presents a major challenge when estimating time-series models that are robust to overfitting and have well-calibrated uncertainty estimates. Most of the current literature in these fields involve visualizing the time-series for noticeabl...

  13. Golden Mountain Reading Series. Teacher's Guide, Level 2.

    Science.gov (United States)

    Sung, Robert

    This reading series was developed as a means to educate Chinese-American elementary school students in Chinese reading, writing, and culture. The following topics are covered: Chinese literature, Chinese and American history, famous people, general knowledge, Chinese ideography, the four seasons, and the major Chinese and American festivals and…

  14. Estimation of daily maximum and minimum air temperatures in urban landscapes using MODIS time series satellite data

    Science.gov (United States)

    Yoo, Cheolhee; Im, Jungho; Park, Seonyoung; Quackenbush, Lindi J.

    2018-03-01

    Urban air temperature is considered a significant variable for a variety of urban issues, and analyzing the spatial patterns of air temperature is important for urban planning and management. However, insufficient weather stations limit accurate spatial representation of temperature within a heterogeneous city. This study used a random forest machine learning approach to estimate daily maximum and minimum air temperatures (Tmax and Tmin) for two megacities with different climate characteristics: Los Angeles, USA, and Seoul, South Korea. This study used eight time-series land surface temperature (LST) data from Moderate Resolution Imaging Spectroradiometer (MODIS), with seven auxiliary variables: elevation, solar radiation, normalized difference vegetation index, latitude, longitude, aspect, and the percentage of impervious area. We found different relationships between the eight time-series LSTs with Tmax/Tmin for the two cities, and designed eight schemes with different input LST variables. The schemes were evaluated using the coefficient of determination (R2) and Root Mean Square Error (RMSE) from 10-fold cross-validation. The best schemes produced R2 of 0.850 and 0.777 and RMSE of 1.7 °C and 1.2 °C for Tmax and Tmin in Los Angeles, and R2 of 0.728 and 0.767 and RMSE of 1.1 °C and 1.2 °C for Tmax and Tmin in Seoul, respectively. LSTs obtained the day before were crucial for estimating daily urban air temperature. Estimated air temperature patterns showed that Tmax was highly dependent on the geographic factors (e.g., sea breeze, mountains) of the two cities, while Tmin showed marginally distinct temperature differences between built-up and vegetated areas in the two cities.

  15. Ciencias 1. Manual do Professor (Science 1. Teacher's Manual).

    Science.gov (United States)

    Raposo, Lucilia

    This is the teacher's guide for Ciencias 1, the first in a series of science books designed for Portuguese-speaking students in elementary schools. The guide contains materials corresponding to the student's book. Included are five sections comprised of 43 lessons. The teacher's guide also contains lesson objectives, suggestions for lesson…

  16. The Elusive Neutrino, Understanding the Atom Series.

    Science.gov (United States)

    Bernstein, Jeremy

    This booklet is one of the booklets in the "Understanding the Atom Series" published by the U. S. Atomic Energy Commission for high school science teachers and their students. The discovery of the neutrino and the research involving this important elementary particle of matter is discussed. The introductory section reviews topics basic…

  17. Estimations of the Global Distribution and Time Series of UV Noontime Irradiance (305, 310, 324, 380 nm, and Erythemal) from TOMS and SeaWiFS Data

    Science.gov (United States)

    Herman, J.

    2004-01-01

    The amount of UV irradiance reaching the Earth's surface is estimated from the measured cloud reflectivity, ozone, aerosol amounts, and surface reflectivity time series from 1980 to 1992 and 1997 to 2000 to estimate changes that have occurred over a 21-year period. Recent analysis of the TOMS data shows that there has been an apparent increase in reflectivity (decrease in W) in the Southern Hemisphere that is related to a calibration error in EP-TOMS. Data from the well-calibrated SeaWiFS satellite instrument have been used to correct the EP-TOMS reflectivity and UV time series. After correction, some of the local trend features seen in the N7 time series (1980 to 1992) have been continued in the combined time series, but the overall zonal average and global trends have changed. In addition to correcting the EP-TOMS radiance calibration, the use of SeaWiFS cloud data permits estimation of UV irradiance at higher spatial resolution (1 to 4 km) than is available from TOMS (100 km) under the assumption that ozone is slowly varying over a scale of 100 km. The key results include a continuing decrease in cloud cover over Europe and North America with a corresponding increase in UV and a decrease in UV irradiance near Antarctica.

  18. Estimating soil hydraulic properties from soil moisture time series by inversion of a dual-permeability model

    Science.gov (United States)

    Dalla Valle, Nicolas; Wutzler, Thomas; Meyer, Stefanie; Potthast, Karin; Michalzik, Beate

    2017-04-01

    Dual-permeability type models are widely used to simulate water fluxes and solute transport in structured soils. These models contain two spatially overlapping flow domains with different parameterizations or even entirely different conceptual descriptions of flow processes. They are usually able to capture preferential flow phenomena, but a large set of parameters is needed, which are very laborious to obtain or cannot be measured at all. Therefore, model inversions are often used to derive the necessary parameters. Although these require sufficient input data themselves, they can use measurements of state variables instead, which are often easier to obtain and can be monitored by automated measurement systems. In this work we show a method to estimate soil hydraulic parameters from high frequency soil moisture time series data gathered at two different measurement depths by inversion of a simple one dimensional dual-permeability model. The model uses an advection equation based on the kinematic wave theory to describe the flow in the fracture domain and a Richards equation for the flow in the matrix domain. The soil moisture time series data were measured in mesocosms during sprinkling experiments. The inversion consists of three consecutive steps: First, the parameters of the water retention function were assessed using vertical soil moisture profiles in hydraulic equilibrium. This was done using two different exponential retention functions and the Campbell function. Second, the soil sorptivity and diffusivity functions were estimated from Boltzmann-transformed soil moisture data, which allowed the calculation of the hydraulic conductivity function. Third, the parameters governing flow in the fracture domain were determined using the whole soil moisture time series. The resulting retention functions were within the range of values predicted by pedotransfer functions apart from very dry conditions, where all retention functions predicted lower matrix potentials

  19. Quirky patterns in time-series of estimates of recruitment could be artefacts

    DEFF Research Database (Denmark)

    Dickey-Collas, M.; Hinzen, N.T.; Nash, R.D.M.

    2015-01-01

    of recruitment time-series in databases is therefore not consistent across or within species and stocks. Caution is therefore required as perhaps the characteristics of the time-series of stock dynamics may be determined by the model used to generate them, rather than underlying ecological phenomena......The accessibility of databases of global or regional stock assessment outputs is leading to an increase in meta-analysis of the dynamics of fish stocks. In most of these analyses, each of the time-series is generally assumed to be directly comparable. However, the approach to stock assessment...... employed, and the associated modelling assumptions, can have an important influence on the characteristics of each time-series. We explore this idea by investigating recruitment time-series with three different recruitment parameterizations: a stock–recruitment model, a random-walk time-series model...

  20. Teacher in Residence: Bringing Science to Students

    CERN Multimedia

    Daisy Yuhas

    CERN welcomes its first Teacher in Residence, Terrence Baine of the University of Oslo. Baine, who originally hails from Canada, will be concurrently completing his PhD in Physics Education during his time at CERN. Like CERN’s High School Teacher Programme (HST), of which Baine is an alumnus, the Teacher in Residence position is designed to help educators spread the science of CERN in a form that is accessible to students and can encourage them to pursue physics throughout their education.   Terrence Baine, first 'teacher in residence' at CERN Baine explains, “It’s very important to have a teacher present who can be that middle person between the young peoplecoming here, whom we are trying to enlighten, and the physicists who work at CERN. The Teacher in Residence can act as an on-site educational consultant.” As Teacher in Residence, Baine’s primary project will be to develop teaching modules, or a series of lesson plans, that can help high schoo...

  1. Review of "Assessing the Compensation of Public-School Teachers"

    Science.gov (United States)

    Keefe, Jeffrey H.

    2012-01-01

    This report compares the pay, pension costs and retiree health benefits of teachers with those of similarly qualified private-sector workers. The study concludes that teachers receive total compensation 52% greater than fair market levels, which translates into a $120 billion annual "overcharge" to taxpayers. Built on a series of faulty analyses,…

  2. What Successful Science Teachers Do: 75 Research-Based Strategies

    Science.gov (United States)

    Glasgow, Neal A.; Cheyne, Michele; Yerrick, Randy K.

    2010-01-01

    The experience and science expertise of these award-winning authors makes this easy-to-use guide a teacher's treasure trove. This latest edition to the popular What Successful Teachers Do series describes 75 research-based strategies and outlines best practices for inquiry-oriented science. Each strategy includes a brief description of the…

  3. Science Teachers' Pedagogical Discontentment: Its Sources and Potential for Change

    Science.gov (United States)

    Southerland, Sherry A.; Sowell, Scott; Enderle, Patrick

    2011-01-01

    This research explored science teachers' pedagogical discontentment and described its role in teachers' consideration of new teaching practices. Pedagogical discontentment is an expression of the degree to which one is discontented because one's teaching practices do not achieve one's teaching goals. Through a series of structured interviews…

  4. Difficulties and challenges for newly qualified ELE (Spanish as a Foreign Language teachers

    Directory of Open Access Journals (Sweden)

    Ligia Ochoa Sierra

    2014-05-01

    Full Text Available The research presented here shows the results obtained from a series of interviews conducted with teachers who work as teachers of Spanish as a foreign language about the most important difficulties and challenges which such teachers face at the beginning of their career

  5. Time series of low-degree geopotential coefficients from SLR data: estimation of Earth's figure axis and LOD variations

    Science.gov (United States)

    Luceri, V.; Sciarretta, C.; Bianco, G.

    2012-12-01

    The redistribution of the mass within the earth system induces changes in the Earth's gravity field. In particular, the second-degree geopotential coefficients reflect the behaviour of the Earth's inertia tensor of order 2, describing the main mass variations of our planet impacting the EOPs. Thanks to the long record of accurate and continuous laser ranging observations to Lageos and other geodetic satellites, SLR is the only current space technique capable to monitor the long time variability of the Earth's gravity field with adequate accuracy. Time series of low-degree geopotential coefficients are estimated with our analysis of SLR data (spanning more than 25 years) from several geodetic satellites in order to detect trends and periodic variations related to tidal effects and atmospheric/oceanic mass variations. This study is focused on the variations of the second-degree Stokes coefficients related to the Earth's principal figure axis and oblateness: C21, S21 and C20. On the other hand, surface mass load variations induce excitations in the EOPs that are proportional to the same second-degree coefficients. The time series of direct estimates of low degree geopotential and those derived from the EOP excitation functions are compared and presented together with their time and frequency analysis.

  6. A probabilistic method for the estimation of ocean surface currents from short time series of HF radar data

    Science.gov (United States)

    Guérin, Charles-Antoine; Grilli, Stéphan T.

    2018-01-01

    We present a new method for inverting ocean surface currents from beam-forming HF radar data. In contrast with the classical method, which inverts radial currents based on shifts of the main Bragg line in the radar Doppler spectrum, the method works in the temporal domain and inverts currents from the amplitude modulation of the I and Q radar time series. Based on this principle, we propose a Maximum Likelihood approach, which can be combined with a Bayesian inference method assuming a prior current distribution, to infer values of the radial surface currents. We assess the method performance by using synthetic radar signal as well as field data, and systematically comparing results with those of the Doppler method. The new method is found advantageous for its robustness to noise at long range, its ability to accommodate shorter time series, and the possibility to use a priori information to improve the estimates. Limitations are related to current sign errors at far-ranges and biased estimates for small current values and very short samples. We apply the new technique to a data set from a typical 13.5 MHz WERA radar, acquired off of Vancouver Island, BC, and show that it can potentially improve standard synoptic current mapping.

  7. MODIS-derived EVI, NDVI and WDRVI time series to estimate phenological metrics in French deciduous forests

    Science.gov (United States)

    Testa, S.; Soudani, K.; Boschetti, L.; Borgogno Mondino, E.

    2018-02-01

    Monitoring forest phenology allows us to study the effects of climate change on vegetated land surfaces. Daily and composite time series (TS) of several vegetation indices (VIs) from MODerate resolution Imaging Spectroradiometer (MODIS) data have been widely used in scientific works for phenological studies since the beginning of the MODIS mission. The objective of this work was to use MODIS data to find the best VI/TS combination to estimate start-of-season (SOS) and end-of-season (EOS) dates across 50 temperate deciduous forests. Our research used as inputs 2001-2012 daily reflectance from MOD09GQ/MOD09GA products and 16-day composite VIs from the MOD13Q1 dataset. The 50 pixels centered on the 50 forest plots were extracted from the above-mentioned MODIS imagery; we then generated 5 different types of TS (1 daily from MOD09 and 4 composite from MOD13Q1) and used all of them to implement 6 VIs, obtaining 30 VI/TS combinations. SOS and EOS estimates were determined for each pixel/year and each VI/TS combination. SOS/EOS estimations were then validated against ground phenological observations. Results showed that, in our test areas, composite TS, if actual acquisition date is considered, performed mostly better than daily TS. EVI, WDRVI0.20 and NDVI were more suitable to SOS estimation, while WDRVI0.05 and EVI were more convenient in estimating early and advanced EOS, respectively.

  8. Covariance matrix estimation for stationary time series

    OpenAIRE

    Xiao, Han; Wu, Wei Biao

    2011-01-01

    We obtain a sharp convergence rate for banded covariance matrix estimates of stationary processes. A precise order of magnitude is derived for spectral radius of sample covariance matrices. We also consider a thresholded covariance matrix estimator that can better characterize sparsity if the true covariance matrix is sparse. As our main tool, we implement Toeplitz [Math. Ann. 70 (1911) 351–376] idea and relate eigenvalues of covariance matrices to the spectral densities or Fourier transforms...

  9. A Study of the Generalizability of Teacher Change Quasi-Experiments

    Science.gov (United States)

    Stringfield, Samuel; Schaffer, Eugene; Devlin-Scherer, Roberta

    2017-01-01

    Quasi-experimental teacher effectiveness studies have indicated that properly designed staff development programs can lead to changes in teacher and student behavior and to gains in student achievement. Those studies involved workshop series led by nationally known scholars. Using instructors from varied backgrounds, the current study examined the…

  10. Teachers Performing Professionalism

    Directory of Open Access Journals (Sweden)

    Terri Bourke

    2013-10-01

    Full Text Available Faced with the perceived need to redefine education for more economic utilitarian purposes, as well as to encourage compliance with government policies, Australia, like many other Anglophone nations, has engaged in numerous policy shifts resulting in performativity practices becoming commonplace in the educational landscape. A series of interviews with teachers from Queensland, Australia, in which they revealed their experiences of professionalism are examined archaeologically to reveal how they enact their roles in response to this performative agenda. Findings suggest that while there is some acceptance among teachers of the performative discourse, there is increasing resistance, which permits the construction of alternative or counter-discourses to the currently internationally pervasive performative climate.

  11. A simulation study to quantify the impacts of exposure measurement error on air pollution health risk estimates in copollutant time-series models.

    Science.gov (United States)

    BackgroundExposure measurement error in copollutant epidemiologic models has the potential to introduce bias in relative risk (RR) estimates. A simulation study was conducted using empirical data to quantify the impact of correlated measurement errors in time-series analyses of a...

  12. The inverse Numerical Computer Program FLUX-BOT for estimating Vertical Water Fluxes from Temperature Time-Series.

    Science.gov (United States)

    Trauth, N.; Schmidt, C.; Munz, M.

    2016-12-01

    Heat as a natural tracer to quantify water fluxes between groundwater and surface water has evolved to a standard hydrological method. Typically, time series of temperatures in the surface water and in the sediment are observed and are subsequently evaluated by a vertical 1D representation of heat transport by advection and dispersion. Several analytical solutions as well as their implementation into user-friendly software exist in order to estimate water fluxes from the observed temperatures. Analytical solutions can be easily implemented but assumptions on the boundary conditions have to be made a priori, e.g. sinusoidal upper temperature boundary. Numerical models offer more flexibility and can handle temperature data which is characterized by irregular variations such as storm-event induced temperature changes and thus cannot readily be incorporated in analytical solutions. This also reduced the effort of data preprocessing such as the extraction of the diurnal temperature variation. We developed a software to estimate water FLUXes Based On Temperatures- FLUX-BOT. FLUX-BOT is a numerical code written in MATLAB which is intended to calculate vertical water fluxes in saturated sediments, based on the inversion of measured temperature time series observed at multiple depths. It applies a cell-centered Crank-Nicolson implicit finite difference scheme to solve the one-dimensional heat advection-conduction equation. Besides its core inverse numerical routines, FLUX-BOT includes functions visualizing the results and functions for performing uncertainty analysis. We provide applications of FLUX-BOT to generic as well as to measured temperature data to demonstrate its performance.

  13. Reconstructing the science teaching in initial series through continuing education

    Directory of Open Access Journals (Sweden)

    Suzana Margarete Kurzmann Fagundes

    2015-11-01

    Full Text Available This paper presents the report of an investigation whose aim was to know the focus on Science teaching in initial series of elementary school and to understand the contributions of teacher’s participation in study groups for transformation of teaching practice in Sciences classes. It’s believed that the role of teachers is to give to their students opportunities for construction/reconstruction of knowledge. Thus, there is essential that teachers keep themselves in constant training The study was conducted with teachers of initial series (to 1st from 4th from a school from the Rio Grande do Sul (RS state in the 2006 / 2007 period. A qualitative analysis methodology was employed in this study, and data was obtained in the natural environment, namely,the school. Through Discoursive Textual Analysis (MORAES and GALIAZZI, 2007 about the data that was collected, it was concluded that the study groups can contribute to transformation and to development of pedagogical teacher’s practice, particularly in regard to Sciences classes, as well on student learning, ie the construction of their knowledge. It has been observed a growth of the group in the course of the meetings, not only by the concern of the teachers in changing their classes, but also to taking the necessary decisions to make it possible.

  14. Remediation of Math Anxiety in Preservice Elementary School Teachers

    Science.gov (United States)

    Dunkle, Susan M.

    2010-01-01

    The purpose of this study was to measure the level of math anxiety in preservice elementary teachers, and then to determine if remediation methods would lower the measured level of anxiety in these same preservice teachers. The 10-day study provided an intense remediation using a time-series design to measure change on the Revised Math Anxiety…

  15. Teacher's Guide to SERAPHIM Software V. Chemistry: The Central Science.

    Science.gov (United States)

    Bogner, Donna J.

    Designed to assist chemistry teachers in selecting appropriate software programs, this publication is the fifth in a series of six teacher's guides from Project SERAPHIM, a program sponsored by the National Science Foundation. This guide is keyed to the chapters of the text "Chemistry: The Central Science." Program suggestions are…

  16. The Black Man on Film: Racial Stereotyping. Hayden Film Attitudes and Issues Series.

    Science.gov (United States)

    Maynard, Richard A.

    Motion pictures have long been recognized as a mirror of society's values and attitudes, and for motivational and impression-making impact they are unsurpassed. The Hayden Film Attitudes and Issues Series is based on the teacher's source book, the Celluloid Curriculum: How to Use Movies in the Classroom. This series presents written sources…

  17. Stephen Hawking's Universe. Teacher's Guide.

    Science.gov (United States)

    Thompson, Malcolm H.; Rameau, Jonathan D.

    This program guide is meant to help teachers assist their students in viewing the six-part public television series, "Stephen Hawking's Universe." The guide features program summaries that give background information and brief synopses of the programs; previewing activities that familiarize students with the subject; vocabulary that…

  18. Improving artificial forest biomass estimates using afforestation age information from time series Landsat stacks.

    Science.gov (United States)

    Liu, Liangyun; Peng, Dailiang; Wang, Zhihui; Hu, Yong

    2014-11-01

    China maintains the largest artificial forest area in the world. Studying the dynamic variation of forest biomass and carbon stock is important to the sustainable use of forest resources and understanding of the artificial forest carbon budget in China. In this study, we investigated the potential of Landsat time series stacks for aboveground biomass (AGB) estimation in Yulin District, a key region of the Three-North Shelter region of China. Firstly, the afforestation age was successfully retrieved from the Landsat time series stacks in the last 40 years (from 1974 to 2013) and shown to be consistent with the surveyed tree ages, with a root-mean-square error (RMSE) value of 4.32 years and a determination coefficient (R (2)) of 0.824. Then, the AGB regression models were successfully developed by integrating vegetation indices and tree age. The simple ratio vegetation index (SR) is the best candidate of the commonly used vegetation indices for estimating forest AGB, and the forest AGB model was significantly improved using the combination of SR and tree age, with R (2) values from 0.50 to 0.727. Finally, the forest AGB images were mapped at eight epochs from 1985 to 2013 using SR and afforestation age. The total forest AGB in seven counties of Yulin District increased by 20.8 G kg, from 5.8 G kg in 1986 to 26.6 G kg in 2013, a total increase of 360 %. For the persistent forest area since 1974, the forest AGB density increased from 15.72 t/ha in 1986 to 44.53 t/ha in 2013, with an annual rate of about 0.98 t/ha. For the artificial forest planted after 1974, the AGB density increased about 1.03 t/ha a year from 1974 to 2013. The results present a noticeable carbon increment for the planted artificial forest in Yulin District over the last four decades.

  19. Time Series with Long Memory

    OpenAIRE

    西埜, 晴久

    2004-01-01

    The paper investigates an application of long-memory processes to economic time series. We show properties of long-memory processes, which are motivated to model a long-memory phenomenon in economic time series. An FARIMA model is described as an example of long-memory model in statistical terms. The paper explains basic limit theorems and estimation methods for long-memory processes in order to apply long-memory models to economic time series.

  20. Entropy estimates of small data sets

    Energy Technology Data Exchange (ETDEWEB)

    Bonachela, Juan A; Munoz, Miguel A [Departamento de Electromagnetismo y Fisica de la Materia and Instituto de Fisica Teorica y Computacional Carlos I, Facultad de Ciencias, Universidad de Granada, 18071 Granada (Spain); Hinrichsen, Haye [Fakultaet fuer Physik und Astronomie, Universitaet Wuerzburg, Am Hubland, 97074 Wuerzburg (Germany)

    2008-05-23

    Estimating entropies from limited data series is known to be a non-trivial task. Naive estimations are plagued with both systematic (bias) and statistical errors. Here, we present a new 'balanced estimator' for entropy functionals (Shannon, Renyi and Tsallis) specially devised to provide a compromise between low bias and small statistical errors, for short data series. This new estimator outperforms other currently available ones when the data sets are small and the probabilities of the possible outputs of the random variable are not close to zero. Otherwise, other well-known estimators remain a better choice. The potential range of applicability of this estimator is quite broad specially for biological and digital data series. (fast track communication)

  1. Entropy estimates of small data sets

    International Nuclear Information System (INIS)

    Bonachela, Juan A; Munoz, Miguel A; Hinrichsen, Haye

    2008-01-01

    Estimating entropies from limited data series is known to be a non-trivial task. Naive estimations are plagued with both systematic (bias) and statistical errors. Here, we present a new 'balanced estimator' for entropy functionals (Shannon, Renyi and Tsallis) specially devised to provide a compromise between low bias and small statistical errors, for short data series. This new estimator outperforms other currently available ones when the data sets are small and the probabilities of the possible outputs of the random variable are not close to zero. Otherwise, other well-known estimators remain a better choice. The potential range of applicability of this estimator is quite broad specially for biological and digital data series. (fast track communication)

  2. Into Adolescence: Fitness, Health and Hygiene. A Curriculum for Grades 5-8. Contemporary Health Series.

    Science.gov (United States)

    Garzino, Mary S.

    The Contemporary Health Series is intended to help teachers address critical health issues in their classrooms. It is designed to provide educators with the curricular tools necessary to challenge students to take personal responsibility for their health. This learning module, directed at middle school teachers, focuses on several health and…

  3. Water Pollution, Teachers' Edition.

    Science.gov (United States)

    Lavaroni, Charles W.; And Others

    One of three in a series about pollution, this teacher's guide for a unit on water pollution is designed for use in junior high school grades. It offers suggestions for extending the information and activities contained in the textual material for students. Chapter 1 discusses the problem of water pollution and involves students in processes of…

  4. Noise Pollution, Teachers' Edition.

    Science.gov (United States)

    O'Donnell, Patrick A.; Lavaroni, Charles W.

    One of three in a series about pollution, this teacher's guide for a unit on noise pollution is designed for use in junior high school grades. It offers suggestions for extending the information and activities contained in the textual material for students. Chapter 1 discusses the problem of noise pollution and involves students in processes of…

  5. Assessing teachers' positive psychological functioning at work: Development and validation of the Teacher Subjective Wellbeing Questionnaire.

    Science.gov (United States)

    Renshaw, Tyler L; Long, Anna C J; Cook, Clayton R

    2015-06-01

    This study reports on the initial development and validation of the Teacher Subjective Wellbeing Questionnaire (TSWQ) with 2 samples of educators-a general sample of 185 elementary and middle school teachers, and a target sample of 21 elementary school teachers experiencing classroom management challenges. The TSWQ is an 8-item self-report instrument for assessing teachers' subjective wellbeing, which is operationalized via subscales measuring school connectedness and teaching efficacy. The conceptualization and development processes underlying the TSWQ are described, and results from a series of preliminary psychometric and exploratory analyses are reported to establish initial construct validity. Findings indicated that the TSWQ was characterized by 2 conceptually sound latent factors, that both subscales and the composite scale demonstrated strong internal consistency, and that all scales demonstrated convergent validity with self-reported school supports and divergent validity with self-reported stress and emotional burnout. Furthermore, results indicated that TSWQ scores did not differ according to teachers' school level (i.e., elementary vs. middle), but that they did differ according to unique school environment (e.g., 1 middle school vs. another middle school) and teacher stressors (i.e., general teachers vs. teachers experiencing classroom management challenges). Results also indicated that, for teachers experiencing classroom challenges, the TSWQ had strong short-term predictive validity for psychological distress, accounting for approximately half of the variance in teacher stress and emotional burnout. Implications for theory, research, and the practice of school psychology are discussed. (c) 2015 APA, all rights reserved).

  6. Small Victories: Reflections on Teaching "Harry Potter" to Resistant Prospective Teachers.

    Science.gov (United States)

    Bercaw, Lynne A.

    2003-01-01

    Describes the author's interactions with prospective teachers' resistances to books in the "Harry Potter" series and how she dealt with these situations. Recognizes that her role as a teacher educator includes honoring her students' beliefs, upholding the integrity of the academic discipline of children's literature, and adhering to the…

  7. [The readiness of the young teacher for the job].

    Science.gov (United States)

    Ruskova, R

    1992-01-01

    The study aims at studying the professional readiness of the young teachers concerning their psychic state. It includes subjective-individual determinants--attitude to the profession, professional choice and steadiness, professional skills and satisfaction. The investigation is part of a broad complex study. The method used is directed first of all to self-estimation of the teacher concerning the structural system of the pedagogic activity which embraces supplementary questionnaire, revealing the motivation side of the scales for self-estimation. The subject of the examination are teachers from primary schools with length of service one to five years--time for completing their adaptation to the profession. The investigation includes 40 teachers from the cities of Sofia and Burgas. A general conclusion could be made, that there is professional readiness of the young teacher to be up to the requirements. His/her self-estimation corresponds to the adaptive behaviour and the choice of profession has a considerable effect on the professional steadiness. The general low satisfaction is not a sign for dysadaptation, but this low level presupposes lack of stimuli for personal development and perfection.

  8. Examining Teachers' Hurdles to `Science for All'

    Science.gov (United States)

    Southerland, Sherry; Gallard, Alejandro; Callihan, Laurie

    2011-11-01

    The goal of this research is to identify science teachers' beliefs and conceptions that play an important role in shaping their understandings of and attempts to enact inclusive science teaching practices. We examined the work products, both informal (online discussions, email exchanges) and formal (papers, unit plans, peer reviews), of 14 teachers enrolled in a master's degree course focused on diversity in science teaching and learning. These emerging understandings were member-checked via a series of interviews with a subset of these teachers. Our analysis was conducted in two stages: (1) describing the difficulties the teachers identified for themselves in their attempts to teach science to a wide range of students in their classes and (2) analyzing these self-identified barriers for underlying beliefs and conceptions that serve to prohibit or allow for the teachers' understanding and enactment of equitable science instruction. The teachers' self-identified barriers were grouped into three categories: students, broader social infrastructure, and self. The more fundamental barriers identified included teacher beliefs about the ethnocentrism of the mainstream, essentialism/individualism, and beliefs about the meritocracy of schooling. The implications of these hurdles for science teacher education are discussed.

  9. Enhancing Science Teacher Training Using Water Resources and GLOBE

    Science.gov (United States)

    Falco, James W.

    2002-01-01

    Heritage College, located on the Yakama Indian Reservation in south central Washington state, serves a multicultural, underserved, rural population and trains teachers to staff the disadvantaged school districts on and surrounding the reservation. In-service teachers and pre-service teachers in the area show strength in biology but have weak backgrounds in chemistry and mathematics. We are addressing this problem by providing a 2-year core of courses for 3 groups of 25 students (15 pre-service and 10 in-service teachers) using GLOBE to teach integrated physical science and mathematics. At the conclusion of the program, the students will qualify for science certification by Washington State. Water resources are the focal point of the curriculum because it is central to life in our desert area. The lack or excess of water, its uses, quality and distribution is being studied by using GIS, remote sensing and historical records. Students are learning the methodology to incorporate scientific protocols and data into all aspects of their future teaching curriculum. In addition, in each of the three years of the project, pre-service teachers attended a seminar series during the fall semester with presentations by collaborators from industry, agriculture, education and government agencies. Students used NASA educational materials in the presentations that they gave at the conclusion of the seminar series. All pre- and in-service teachers continue to have support via a local web site for Heritage College GLOBE participants.

  10. Reflective and Reflexive Beliefs of Two Pre-Service Secondary Mathematics Teachers

    Science.gov (United States)

    Belbase, Shashidhar

    2016-01-01

    The objective of this paper is to present two preservice secondary mathematics teachers' beliefs about teaching Geometric Transformations (GTs) using Geometer?s Sketchpad (GSP). The study comprised of series of five task-based interviews with each of two participants, who were senior undergraduate preservice teachers, at a medium-sized public…

  11. Teacher Challenges to Implement Engineering Design in Secondary Technology Education

    Science.gov (United States)

    Kelley, Todd R.; Wicklein, Robert C.

    2009-01-01

    This descriptive study examined the current status of technology education teacher practices with respect to engineering design. This article is the third article in a three-part series presenting the results of this study. The first article in the series titled "Examination of Engineering Design Curriculum Content" highlighted the research…

  12. Analysing Stable Time Series

    National Research Council Canada - National Science Library

    Adler, Robert

    1997-01-01

    We describe how to take a stable, ARMA, time series through the various stages of model identification, parameter estimation, and diagnostic checking, and accompany the discussion with a goodly number...

  13. Effective teaching in the contexts of Internet science projects: American and Russian teachers' perspectives of best practices

    Science.gov (United States)

    Mumma, Brian

    Statement of the problem. Science education literature had agreed that an important goal in students' learning is the development of scientific and technological literacy. One effort that teachers have integrated into their practices for addressing this goal has been teaching within the contexts of Internet Science Projects. Greater awareness of teachers' perspectives of their best practices and their beliefs and reasons for these practices in the contexts of Internet Science Projects can improve the quality of science education programs. Methods. A series of pilot interviews was conducted during the 2000--2001 school year to develop the guiding questions for inquiring into teachers' perspectives of their best practices within the contexts of Internet Science Projects. This series of interviews resulted in the understanding of the need to select teachers with experiences with Internet Science Projects and to conduct in-depth phenomenological interviews for learning from their voices. Two teachers were purposefully selected as the participant-informants for this study, one an American elementary teacher from Walker County, Georgia, and one a Russian teacher from St. Petersburg, Russia. The study was conducted from October through December 2001. The data collected for this qualitative study consisted of a series of in-depth phenomenological interviews, classroom observations, and the collection and analysis of various artifacts including teacher journals, student products, and e-mail/bulletin board transcripts. The interview structure was based upon a modification of expanding Seidman's (1998) three interview series into multiple interviews concluded upon the determination of saturation of the topic. The series of interviews were composed of (1) life history focus; (2) the details of the experience of teaching within the contexts of Internet Science Projects; and (3) reflection on the meanings. The data analysis consisted of applying Strauss & Corbin's (1990) open

  14. Identified Phases in the Building and Maintaining of Positive Teacher-Student Relationships

    Science.gov (United States)

    Newberry, Melissa

    2010-01-01

    Teacher-student relationships are accepted as influential but the dynamics of those relationships are not well understood, especially with difficult students. A series of interviews were combined with classroom observations and written reflections to understand in what ways a teacher negotiated her relationship with a behaviorally challenging…

  15. Multivariate Time Series Decomposition into Oscillation Components.

    Science.gov (United States)

    Matsuda, Takeru; Komaki, Fumiyasu

    2017-08-01

    Many time series are considered to be a superposition of several oscillation components. We have proposed a method for decomposing univariate time series into oscillation components and estimating their phases (Matsuda & Komaki, 2017 ). In this study, we extend that method to multivariate time series. We assume that several oscillators underlie the given multivariate time series and that each variable corresponds to a superposition of the projections of the oscillators. Thus, the oscillators superpose on each variable with amplitude and phase modulation. Based on this idea, we develop gaussian linear state-space models and use them to decompose the given multivariate time series. The model parameters are estimated from data using the empirical Bayes method, and the number of oscillators is determined using the Akaike information criterion. Therefore, the proposed method extracts underlying oscillators in a data-driven manner and enables investigation of phase dynamics in a given multivariate time series. Numerical results show the effectiveness of the proposed method. From monthly mean north-south sunspot number data, the proposed method reveals an interesting phase relationship.

  16. Brakes Specialist. Teacher Edition. Automotive Service Series. Second Edition.

    Science.gov (United States)

    Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    This curriculum guide for automatic brakes service is one in a series of automotive service speciality publications that is based on the National Institute of Automotive Service Excellence task lists. The curriculum is composed of four units. Each unit of instruction may contain some or all of the following components: objective sheet, suggested…

  17. Lasers. Technology Learning Activity. Teacher Edition. Technology Education Series.

    Science.gov (United States)

    Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    This document contains the materials required for presenting an 8-day competency-based technology learning activity (TLA) designed to introduce students in grades 6-10 to advances and career opportunities in the field of laser technology. The guide uses a series of hands-on exploratory experiences into which activities to help students develop…

  18. Student and Teacher Success: The Impact of Computers in Primary Grades.

    Science.gov (United States)

    Drexler, Nancy Gadzuk; And Others

    This paper discusses the impact of computers on student learning as reported by teachers participating in a study of a computer-based language arts instructional program for the early elementary grades--the Apple Learning Series: Early Language (ALS-EL). Although they found the program difficult to evaluate, some teachers stated that the ALS-EL…

  19. The Use of Piecewise Growth Models to Estimate Learning Trajectories and RtI Instructional Effects in a Comparative Interrupted Time-Series Design

    Science.gov (United States)

    Zvoch, Keith

    2016-01-01

    Piecewise growth models (PGMs) were used to estimate and model changes in the preliteracy skill development of kindergartners in a moderately sized school district in the Pacific Northwest. PGMs were applied to interrupted time-series (ITS) data that arose within the context of a response-to-intervention (RtI) instructional framework. During the…

  20. Teacher community in elementary charter schools.

    Directory of Open Access Journals (Sweden)

    Marisa Cannata

    2007-05-01

    Full Text Available The organizational context of charter schools may facilitate the formation of a strong teacher community. In particular, a focused school mission and increased control over teacher hiring may lead to stronger teacher professional communities. This paper uses the 1999-2000 Schools and Staffing Survey to compare the level of teacher community in charter public and traditional public schools. It also estimates the effect of various charter policy variables and domains of school autonomy on teacher community. Charter school teachers report higher levels of teacher community than traditional public school teachers do, although this effect is less than one-tenth of a standard deviation and is dwarfed by the effect of a supportive principal, teacher decision-making influence, and school size. Charter public schools authorized by universities showed lower levels of teacher community than those authorized by local school districts. Teachers in charter schools that have flexibility over tenure requirements and the school budget report higher levels of teacher community. This study reveals that charter schools do facilitate the formation of strong teacher communities, although the effect is small. The analysis also suggests that the institutional origin of the charter school and specific areas of policy flexibility may influence teacher community.

  1. How Teacher Turnover Harms Student Achievement

    Science.gov (United States)

    Ronfeldt, Matthew; Loeb, Susanna; Wyckoff, James

    2013-01-01

    Researchers and policymakers often assume that teacher turnover harms student achievement, though recent studies suggest this may not be the case. Using a unique identification strategy that employs school-by-grade level turnover and two classes of fixed-effects models, this study estimates the effects of teacher turnover on over 850,000 New York…

  2. Human futures amongst robot teachers?

    DEFF Research Database (Denmark)

    Nørgård, Rikke Toft; Bhroin, Niamh Ni; Ess, Charles Melvin

    2017-01-01

    In 2009 the world’s first robot teacher, Saya, was introduced into a classroom. Saya could express six basic emotions and shout orders like 'be quiet'. Since 2009, instructional robot technologies have emerged around the world and it is estimated that robot teachers may become a regular...... technological feature in the classroom and even 'take over' from human teachers within the next ten to fifteen years.   The paper set out to examine some of the possible ethical implications for human futures in relation to the immanent rise of robot teachers. This is done through combining perspectives...... on technology coming from design, science and technology, education, and philosophy (McCarthy & Wright, 2004; Jasanoff, 2016; Selwyn 2016; Verbeek, 2011). The framework calls attention to how particular robot teachers institute certain educational, experiential and existential terrains within which human...

  3. Phase correction and error estimation in InSAR time series analysis

    Science.gov (United States)

    Zhang, Y.; Fattahi, H.; Amelung, F.

    2017-12-01

    During the last decade several InSAR time series approaches have been developed in response to the non-idea acquisition strategy of SAR satellites, such as large spatial and temporal baseline with non-regular acquisitions. The small baseline tubes and regular acquisitions of new SAR satellites such as Sentinel-1 allows us to form fully connected networks of interferograms and simplifies the time series analysis into a weighted least square inversion of an over-determined system. Such robust inversion allows us to focus more on the understanding of different components in InSAR time-series and its uncertainties. We present an open-source python-based package for InSAR time series analysis, called PySAR (https://yunjunz.github.io/PySAR/), with unique functionalities for obtaining unbiased ground displacement time-series, geometrical and atmospheric correction of InSAR data and quantifying the InSAR uncertainty. Our implemented strategy contains several features including: 1) improved spatial coverage using coherence-based network of interferograms, 2) unwrapping error correction using phase closure or bridging, 3) tropospheric delay correction using weather models and empirical approaches, 4) DEM error correction, 5) optimal selection of reference date and automatic outlier detection, 6) InSAR uncertainty due to the residual tropospheric delay, decorrelation and residual DEM error, and 7) variance-covariance matrix of final products for geodetic inversion. We demonstrate the performance using SAR datasets acquired by Cosmo-Skymed and TerraSAR-X, Sentinel-1 and ALOS/ALOS-2, with application on the highly non-linear volcanic deformation in Japan and Ecuador (figure 1). Our result shows precursory deformation before the 2015 eruptions of Cotopaxi volcano, with a maximum uplift of 3.4 cm on the western flank (fig. 1b), with a standard deviation of 0.9 cm (fig. 1a), supporting the finding by Morales-Rivera et al. (2017, GRL); and a post-eruptive subsidence on the same

  4. Critical points of multidimensional random Fourier series: variance estimates

    OpenAIRE

    Nicolaescu, Liviu I.

    2013-01-01

    To any positive number $\\varepsilon$ and any nonnegative even Schwartz function $w:\\mathbb{R}\\to\\mathbb{R}$ we associate the random function $u^\\varepsilon$ on the $m$-torus $T^m_\\varepsilon:=\\mathbb{R}^m/(\\varepsilon^{-1}\\mathbb{Z})^m$ defined as the real part of the random Fourier series $$ \\sum_{\

  5. Teacher roles in Learning Games

    DEFF Research Database (Denmark)

    Magnussen, Rikke

    2007-01-01

    the roles as forensic experts who solve a series of murder cases. When teachers use this type of games, they have to adapt to new teaching situations and roles. This includes the fictional role in a game, but also the role as a supervisor for a group of students that play the role as professional experts. I...

  6. Automatic trend estimation

    CERN Document Server

    Vamos¸, C˘alin

    2013-01-01

    Our book introduces a method to evaluate the accuracy of trend estimation algorithms under conditions similar to those encountered in real time series processing. This method is based on Monte Carlo experiments with artificial time series numerically generated by an original algorithm. The second part of the book contains several automatic algorithms for trend estimation and time series partitioning. The source codes of the computer programs implementing these original automatic algorithms are given in the appendix and will be freely available on the web. The book contains clear statement of the conditions and the approximations under which the algorithms work, as well as the proper interpretation of their results. We illustrate the functioning of the analyzed algorithms by processing time series from astrophysics, finance, biophysics, and paleoclimatology. The numerical experiment method extensively used in our book is already in common use in computational and statistical physics.

  7. Reflective Practice as Professional Development: Experiences of Teachers of English in Japan

    Science.gov (United States)

    Watanabe, Atsuko

    2016-01-01

    This book presents a researcher's work on reflective practice with a group of high school teachers of English in Japan. Beginning with a series of uncomfortable teacher training sessions delivered to unwilling participants, the book charts the author's development of new methods of engaging her participants and making use of their own experiences…

  8. Robust Forecasting of Non-Stationary Time Series

    NARCIS (Netherlands)

    Croux, C.; Fried, R.; Gijbels, I.; Mahieu, K.

    2010-01-01

    This paper proposes a robust forecasting method for non-stationary time series. The time series is modelled using non-parametric heteroscedastic regression, and fitted by a localized MM-estimator, combining high robustness and large efficiency. The proposed method is shown to produce reliable

  9. An evaluation of a professional learning network for computer science teachers

    Science.gov (United States)

    Cutts, Quintin; Robertson, Judy; Donaldson, Peter; O'Donnell, Laurie

    2017-01-01

    This paper describes and evaluates aspects of a professional development programme for existing CS teachers in secondary schools (PLAN C) which was designed to support teachers at a time of substantial curricular change. The paper's particular focus is on the formation of a teacher professional development network across several hundred teachers and a wide geographical area. Evidence from a series of observations and teacher surveys over a two-year period is analysed with respect to the project's programme theory in order to illustrate not only whether it worked as intended, by why. Results indicate that the PLAN C design has been successful in increasing teachers' professional confidence and appears to have catalysed powerful change in attitudes to learning. Presentation of challenging pedagogical content knowledge and conceptual frameworks, high-quality teacher-led professional dialogue, along with the space for reflection and classroom trials, triggered examination of the teachers' own current practices.

  10. Minimum Distance Estimation on Time Series Analysis With Little Data

    National Research Council Canada - National Science Library

    Tekin, Hakan

    2001-01-01

    .... Minimum distance estimation has been demonstrated better standard approaches, including maximum likelihood estimators and least squares, in estimating statistical distribution parameters with very small data sets...

  11. Democracy in schools: are educators ready for teacher leadership?

    OpenAIRE

    Elsabé de Villiers; SG (Fanie) Pretorius

    2011-01-01

    The aim of this research was to determine educators' perceptions of and readiness for teacher leadership. A total of 283 educators in the Eden and Central Karoo Education District in the Western Cape participated in the study. The participants included district officials, principals, and members of school management teams, as well as veteran, middle, and novice educators. A series of instruments was used to determine educators' perspectives, perceptions and readiness for teacher leadership, i...

  12. Evaluating clinical teachers with the Maastricht clinical teaching questionnaire: how much 'teacher' is in student ratings?

    Science.gov (United States)

    Boerboom, Tobias B B; Mainhard, Tim; Dolmans, Diana H J M; Scherpbier, Albert J J A; Van Beukelen, Peter; Jaarsma, A D C

    2012-01-01

    Students are a popular source of data to evaluate the performance of clinical teachers. Instruments to obtain student evaluations must have proven validity. One aspect of validity that often remains underexposed is the possibility of effects of between-student differences and teacher and student characteristics not directly related to teaching performance. The authors examined the occurrence of such effects, using multilevel analysis to analyse data from the Maastricht clinical teaching questionnaire (MCTQ), a validated evaluation instrument, in a veterinary curriculum. The 15-item MCTQ covers five domains. The authors used multilevel analysis to divide the variance in the domain scores in components related to, respectively, teachers and students. They estimated subsequent models to explore how the MCTQ scores are dependent on teacher and student characteristics. Significant amounts of variance in student ratings were due to between-teacher differences, particularly for learning climate, modelling and coaching. The effects of teacher and student characteristics were mostly non-significant or small. Large portions of variance in MCTQ scores were due to differences between teachers, while the contribution of student and teacher characteristics was negligible. The results support the validity of student ratings obtained with the MCTQ for evaluating teacher performance.

  13. Fundamentals of Welding. Teacher Edition [and] Student Edition [and] Student Workbook. Second Edition.

    Science.gov (United States)

    Fortney, Clarence; Gregory, Mike; New, Larry

    Teacher and student editions and a student workbook for fundamentals of welding comprise the first of six in a series of competency-based instructional materials for welding programs. Introductory pages in the teacher edition are training and competency profile, instructional/task analysis, basic skills icons and classifications, basic skills…

  14. Identification as Incentive to Care: Pre-Service Teachers' Orientation towards Inclusion in Nature

    Science.gov (United States)

    Gedžune, Inga

    2015-01-01

    This study proposes identification with nature as a pedagogical technique in teacher education for sustainability to facilitate commitment to care about nonhuman nature, such care being an important underpinning of an inclusive and hence sustainable human-nature relationship. 29 pre-service teachers participated in a series of learning activities…

  15. Travelling educational workshops for clinical teachers: are they worthwhile?

    Science.gov (United States)

    Gallagher, Peter; Pullon, Sue

    2011-03-01

    The support of doctors who teach medical students in clinical settings is considered very important. In order to function as effectively as possible in their role as clinical teachers, these clinicians require educational support from faculty members. The most usual form that support takes is university staff offering face-to-face teaching on educational topics. It is estimated that in the course of 1 year, and across the Faculty of Medicine at the University of Otago, there could be up to 600 clinicians actively involved in the direct support of medical students. Many of these clinicians work in locations some considerable distance from the university campus. In 2009 the Medical Education Unit based at the Wellington Campus introduced a series of peripatetic face-to-face workshops for clinical teachers in several different geographical locations. Educational support of this nature is challenging to organise and potentially expensive, which begs the question: are travelling workshops worthwhile? Whereas the subject matter of the workshops was of interest to those who attended, of equal importance was the opportunity the workshops created to interact with colleagues in a relaxed atmosphere. In addition, the workshops were the catalyst for some clinicians to formally pursue their particular educational interests. © Blackwell Publishing Ltd 2011.

  16. A Humanistic Approach to Performance-Based Teacher Education. PBTE Series No. 10.

    Science.gov (United States)

    Nash, Paul

    Questions are reaised in making performance-based teacher education (PBTE) a more humanistic enterprise. A definition of the term "humanistic" could include such qualities as freedom, uniqueness, creativity, productivity, wholeness, responsibility, and social humanization. As to freedom, a humanistic approach to PBTE would encourage people to act…

  17. Iranian Junior High school English Book Series (Right Path to English Weighted against Material Evaluation Checklists

    Directory of Open Access Journals (Sweden)

    Farhad Golpour

    2012-11-01

    Full Text Available Choosing a course textbook is an overwhelming task for both teachers and administrators. The aim of this study was to evaluate Iranian junior high school textbook series base on validated criteria. For this purpose a careful analyzing textbook evaluation checklists suggested by Sheldon (1984 skierso (1991 and Tucker (1992 was picked out. Among proposed criteria, eighteen critical features were selected to analyze Iranian junior high school series written by Birjandi in (1991. The Criteria were applied to the series analytically by researcher to examine the materials. The criteria in a form of questionnaire given to 15 experienced teachers who were teaching mentioned series for more than ten years. The gathered data revealed that it lacks appropriate layout and physical characteristics, materials have not be recycled, not all skills have been considered equally, emphasis is on grammatical points which practiced through speaking and listening. Moreover; recordings are artificial, no attention is paid to students needs and topics are out of date and boring .Also audio-visual materials, teachers’ guide and communicative tasks seems to be forgotten by writer. Therefore; all eighteen features except vocabulary lists, availability of glossary and lots of grammatical points have not been considered a lot. That is, students' interests have been ignored totally and little communicative issues have been regarded in these series. In fact, at end of this determined time students would be proficient at structural points with no efficiency at communication. These findings can be helpful for curriculum designers, textbook writers to design some valuable textbooks that are useful for teachers to teach language communicatively.

  18. Teachers' Perceptions of Bullying among Youth

    Science.gov (United States)

    Bell, Karen J. S.; Willis, W. Grant

    2016-01-01

    A series of 48 vignettes of bullying was constructed by crossing (a) four kinds of social contact (physical aggression, verbal aggression, relational aggression, and non-aggression) with (b) male and female bullies, (c) male and female and victims, and (d) reaction of the victim (aggressive, passive, and no reaction). Teachers rated vignettes for…

  19. Workplace Literacy Teacher Training: The Context.

    Science.gov (United States)

    Harrington, Lois G.; And Others

    These three learning guides comprise one of four packages in the Workplace Literacy Teacher Training series that provides information and skills necessary for the user to become a successful instructor in an effective workplace literacy program. The guides in this package look at the unique environment and culture involved in providing education…

  20. Evaluation of fission-product gases in program GAPCON series and FREG-3 to estimate the gap heat transfer coefficient

    International Nuclear Information System (INIS)

    Ohki, Naohisa; Harayama, Yasuo; Takeda, Tsuneo; Izumi, Fumio.

    1977-12-01

    In safety evaluation of a fuel rod, estimation of the stored energy in the fuel rod is indispensable. For this estimation, the temperature distribution in the fuel rod is calculated. Most important in determination of the temperature distribution is the gap heat transfer coefficient (gap conductance) between pellet surface and cladding inner surface. Under fuel rod operating condition, the mixed gas in the gap is composed of He, Xe and Kr. He is initial seald gas. Xe and Kr are fission-product gases, of which the quantities depend on the fuel burn-up. In program GAPCON series (GAPCON and GAPCON-THERMAL-1 and -2) and FREG-3, these quantities are given as a function of the irradiation time, power rating and neutron flux in estimation of the thermal conductivity of the mixed gas. The methods of calculating the quantities of Xe and Kr in the programs have been examined. Input of the neutron flux which influences F.P. gas production rates is better than the determination from the fuel-rod power rating. (auth.)

  1. Mother and preschool teacher as assessors of the child's language competence

    Directory of Open Access Journals (Sweden)

    Urška Fekonja Peklaj

    2008-04-01

    Full Text Available Many researchers include child's parents as assessors of his/her language development as the results of many studies suggest their assessments to be valid and reliable measures of child's language competence. In the longitudinal study, presented in this paper, we examined whether child's mother and his/her preschool teacher can provide a valid estimation of child's language development. The sample included 80 Slovenian children from different preschool institutions, aged 3;1 years at first and 4;1 years at second assessment. Children's language competence was assessed individually, directly by the testators using Language Development Scale and Storytelling Test and indirectly by mothers and preschool teachers using the Child's Language Competence Questionnaire for Parents and Preschool Teachers. The achieved results showed that the estimates given by mothers and preschool teachers represent valid measures of child's language competence but not stable in time. The estimations given by mothers and preschool teachers explain a small share in variability of children's achievements on the Language Development Scale and Storytelling Test.

  2. Teacher Perspectives on Technology Integration Professional Development: Formal, Informal, and Independent Learning Activities

    Science.gov (United States)

    Jones, Monty; Dexter, Sara

    2018-01-01

    This mixed-methods study examined the technology integration learning activities of four teachers throughout one year using weekly quantitative surveys and a series of three qualitative individual interviews. Through the teachers' own voices an illustration of their learning processes is presented, and the gap between what is supported by their…

  3. Pathways into Teaching: Q&A with Dr. Pam Grossman. REL Mid-Atlantic Teacher Effectiveness Webinar Series

    Science.gov (United States)

    Regional Educational Laboratory Mid-Atlantic, 2013

    2013-01-01

    This webinar explored several elements of teacher preparation pathways, including the history, popularity, and quality of various routes to certification, as well as the impact of these various pathways on teacher quality and retention and student achievement. This Q&A addressed the questions participants had for Dr. Grossman following the…

  4. Predicting chaotic time series

    International Nuclear Information System (INIS)

    Farmer, J.D.; Sidorowich, J.J.

    1987-01-01

    We present a forecasting technique for chaotic data. After embedding a time series in a state space using delay coordinates, we ''learn'' the induced nonlinear mapping using local approximation. This allows us to make short-term predictions of the future behavior of a time series, using information based only on past values. We present an error estimate for this technique, and demonstrate its effectiveness by applying it to several examples, including data from the Mackey-Glass delay differential equation, Rayleigh-Benard convection, and Taylor-Couette flow

  5. Stochastic Models in the DORIS Position Time Series: Estimates from the IDS Contribution to the ITRF2014

    Science.gov (United States)

    Klos, A.; Bogusz, J.; Moreaux, G.

    2017-12-01

    This research focuses on the investigation of the deterministic and stochastic parts of the DORIS (Doppler Orbitography and Radiopositioning Integrated by Satellite) weekly coordinate time series from the IDS contribution to the ITRF2014A set of 90 stations was divided into three groups depending on when the data was collected at an individual station. To reliably describe the DORIS time series, we employed a mathematical model that included the long-term nonlinear signal, linear trend, seasonal oscillations (these three sum up to produce the Polynomial Trend Model) and a stochastic part, all being resolved with Maximum Likelihood Estimation (MLE). We proved that the values of the parameters delivered for DORIS data are strictly correlated with the time span of the observations, meaning that the most recent data are the most reliable ones. Not only did the seasonal amplitudes decrease over the years, but also, and most importantly, the noise level and its type changed significantly. We examined five different noise models to be applied to the stochastic part of the DORIS time series: a pure white noise (WN), a pure power-law noise (PL), a combination of white and power-law noise (WNPL), an autoregressive process of first order (AR(1)) and a Generalized Gauss Markov model (GGM). From our study it arises that the PL process may be chosen as the preferred one for most of the DORIS data. Moreover, the preferred noise model has changed through the years from AR(1) to pure PL with few stations characterized by a positive spectral index.

  6. Integer-valued time series

    NARCIS (Netherlands)

    van den Akker, R.

    2007-01-01

    This thesis adresses statistical problems in econometrics. The first part contributes statistical methodology for nonnegative integer-valued time series. The second part of this thesis discusses semiparametric estimation in copula models and develops semiparametric lower bounds for a large class of

  7. The MetLife Survey of the American Teacher: Challenges for School Leadership

    Science.gov (United States)

    MetLife, Inc., 2013

    2013-01-01

    "The MetLife Survey of the American Teacher: Challenges for School Leadership" (2012) was conducted by Harris Interactive and is the twenty-ninth in a series sponsored annually by MetLife since 1984 to give voice to those closest to the classroom. This report examines the views of teachers and principals on the responsibilities and challenges…

  8. Activation of a critical attitude in prospective teachers: From research investigations to guidelines for teacher education

    Science.gov (United States)

    Viennot, Laurence; Décamp, Nicolas

    2018-06-01

    This paper is inspired by the widely accepted need to develop critical thinking in physics students and teachers. More specifically, it is focused on the development of a critical attitude in prospective physics teachers. The question of a possible interplay between the development of conceptual comprehension and that of a critical attitude prompted us to conduct a series of investigations with teachers at the end of their preparation. The goal of this paper is to provide a synthesis of five previously published papers on this topic in order to inform discussion about teacher preparation. Each investigation is centered on a particular aspect of physics, and all are based on in-depth interviews with different participants. We focus on prospective teachers' "intellectual dynamics," that is, the way their comprehension of nonobvious topics and their critical attitudes evolve during these interviews, taking into account metacognitive and affective aspects such as intellectual satisfaction and self-esteem. We characterize several types of intellectual dynamics: "early critique," "delayed critique," "unstable critique," and "expert anesthesia" and provide information on their frequency. An overall conclusion is that in this type of context, that is, a guided intellectual pathway of about an hour, the development of conceptual comprehension and critical attitude are most often deeply entangled. We discuss the implications of these results for future research and we advocate new objectives and strategies for physics teachers' preparation.

  9. MITRA Virtual laboratory for operative application of satellite time series for land degradation risk estimation

    Science.gov (United States)

    Nole, Gabriele; Scorza, Francesco; Lanorte, Antonio; Manzi, Teresa; Lasaponara, Rosa

    2015-04-01

    This paper aims to present the development of a tool to integrate time series from active and passive satellite sensors (such as of MODIS, Vegetation, Landsat, ASTER, COSMO, Sentinel) into a virtual laboratory to support studies on landscape and archaeological landscape, investigation on environmental changes, estimation and monitoring of natural and anthropogenic risks. The virtual laboratory is composed by both data and open source tools specifically developed for the above mentioned applications. Results obtained for investigations carried out using the implemented tools for monitoring land degradation issues and subtle changes ongoing on forestry and natural areas are herein presented. In detail MODIS, SPOT Vegetation and Landsat time series were analyzed comparing results of different statistical analyses and the results integrated with ancillary data and evaluated with field survey. The comparison of the outputs we obtained for the Basilicata Region from satellite data analyses and independent data sets clearly pointed out the reliability for the diverse change analyses we performed, at the pixel level, using MODIS, SPOT Vegetation and Landsat TM data. Next steps are going to be implemented to further advance the current Virtual Laboratory tools, by extending current facilities adding new computational algorithms and applying to other geographic regions. Acknowledgement This research was performed within the framework of the project PO FESR Basilicata 2007/2013 - Progetto di cooperazione internazionale MITRA "Remote Sensing tecnologies for Natural and Cultural heritage Degradation Monitoring for Preservation and valorization" funded by Basilicata Region Reference 1. A. Lanorte, R Lasaponara, M Lovallo, L Telesca 2014 Fisher-Shannon information plane analysis of SPOT/VEGETATION Normalized Difference Vegetation Index (NDVI) time series to characterize vegetation recovery after fire disturbance International Journal of Applied Earth Observation and

  10. Culinary Arts Teachers Manual. Project HIRE.

    Science.gov (United States)

    Gardner, David C.; And Others

    Designed as supplemental material to on-going instruction in the vocational program, this teacher's manual to the Culinary Arts series is intended to accompany three dictionary booklets (available as CE 024 415-417) for use by handicapped students to help them master the core vocabulary taught in the trade. Information presented in the manual…

  11. Estimating inter-annual variability in winter wheat sowing dates from satellite time series in Camargue, France

    Science.gov (United States)

    Manfron, Giacinto; Delmotte, Sylvestre; Busetto, Lorenzo; Hossard, Laure; Ranghetti, Luigi; Brivio, Pietro Alessandro; Boschetti, Mirco

    2017-05-01

    Crop simulation models are commonly used to forecast the performance of cropping systems under different hypotheses of change. Their use on a regional scale is generally constrained, however, by a lack of information on the spatial and temporal variability of environment-related input variables (e.g., soil) and agricultural practices (e.g., sowing dates) that influence crop yields. Satellite remote sensing data can shed light on such variability by providing timely information on crop dynamics and conditions over large areas. This paper proposes a method for analyzing time series of MODIS satellite data in order to estimate the inter-annual variability of winter wheat sowing dates. A rule-based method was developed to automatically identify a reliable sample of winter wheat field time series, and to infer the corresponding sowing dates. The method was designed for a case study in the Camargue region (France), where winter wheat is characterized by vernalization, as in other temperate regions. The detection criteria were chosen on the grounds of agronomic expertise and by analyzing high-confidence time-series vegetation index profiles for winter wheat. This automatic method identified the target crop on more than 56% (four-year average) of the cultivated areas, with low commission errors (11%). It also captured the seasonal variability in sowing dates with errors of ±8 and ±16 days in 46% and 66% of cases, respectively. Extending the analysis to the years 2002-2012 showed that sowing in the Camargue was usually done on or around November 1st (±4 days). Comparing inter-annual sowing date variability with the main local agro-climatic drivers showed that the type of preceding crop and the weather conditions during the summer season before the wheat sowing had a prominent role in influencing winter wheat sowing dates.

  12. The Mystery of Matter, World of the Atom Series.

    Science.gov (United States)

    Pollard, William G.

    This booklet is one in the "World of the Atome Series" for junior high school students and their teachers. It describes the fascinating story of the search for the key to the structure of matter. These topics are reviewed: the chemical atom of the 19th century, the planetary atom, the wave atom, inside the elementary particles, and the mystery of…

  13. Intercultural Education Series. An Introduction to Selected Latin American Cultures.

    Science.gov (United States)

    Hubert, Frank W. R.; And Others

    This is the first publication in a series developed by the Programa de Educacion Interamericana designed to enrich and strengthen the knowledge and understanding of Texas teachers and students in the field of intercultural education, with particular reference to Mexico and the republics of Central and South America. The project hopes to produce a…

  14. Teacher Research Experience Programs = Increase in Student Achievement

    Science.gov (United States)

    Dubner, J.

    2010-12-01

    Columbia University's Summer Research Program for Science Teachers (SRP), founded in 1990, is one of the largest, best known university-based professional development programs for science teachers in the U.S. The program’s basic premise is simple: teachers cannot effectively teach science if they have not experienced it firsthand. For eight weeks in each of two consecutive summers, teachers participate as a member of a research team, led by a member of Columbia University’s research faculty. In addition to the laboratory experience, all teachers meet as a group one day each week during the summer for a series of pedagogical activities. A unique quality of the Summer Research Program is its focus on objective assessment of its impact on attitudes and instructional practices of participating teachers, on the performance of these teachers in their mentors’ laboratories, and most importantly, on the impact of their participation in the program on student interest and performance in science. SRP uses pass rate on the New York State Regents standardized science examinations as an objective measure of student achievement. SRP's data is the first scientific evidence of a connection between a research experience for teachers program and gains in student achievement. As a result of the research, findings were published in Science Magazine. The author will present an overview of Columbia's teacher research program and the results of the published program evaluation.

  15. Analysis of Heavy-Tailed Time Series

    DEFF Research Database (Denmark)

    Xie, Xiaolei

    This thesis is about analysis of heavy-tailed time series. We discuss tail properties of real-world equity return series and investigate the possibility that a single tail index is shared by all return series of actively traded equities in a market. Conditions for this hypothesis to be true...... are identified. We study the eigenvalues and eigenvectors of sample covariance and sample auto-covariance matrices of multivariate heavy-tailed time series, and particularly for time series with very high dimensions. Asymptotic approximations of the eigenvalues and eigenvectors of such matrices are found...... and expressed in terms of the parameters of the dependence structure, among others. Furthermore, we study an importance sampling method for estimating rare-event probabilities of multivariate heavy-tailed time series generated by matrix recursion. We show that the proposed algorithm is efficient in the sense...

  16. Estimating the basic reproduction rate of HFMD using the time series SIR model in Guangdong, China.

    Directory of Open Access Journals (Sweden)

    Zhicheng Du

    Full Text Available Hand, foot, and mouth disease (HFMD has caused a substantial burden of disease in China, especially in Guangdong Province. Based on notifiable cases, we use the time series Susceptible-Infected-Recovered model to estimate the basic reproduction rate (R0 and the herd immunity threshold, understanding the transmission and persistence of HFMD more completely for efficient intervention in this province. The standardized difference between the reported and fitted time series of HFMD was 0.009 (<0.2. The median basic reproduction rate of total, enterovirus 71, and coxsackievirus 16 cases in Guangdong were 4.621 (IQR: 3.907-5.823, 3.023 (IQR: 2.289-4.292 and 7.767 (IQR: 6.903-10.353, respectively. The heatmap of R0 showed semiannual peaks of activity, including a major peak in spring and early summer (about the 12th week followed by a smaller peak in autumn (about the 36th week. The county-level model showed that Longchuan (R0 = 33, Gaozhou (R0 = 24, Huazhou (R0 = 23 and Qingxin (R0 = 19 counties have higher basic reproduction rate than other counties in the province. The epidemic of HFMD in Guangdong Province is still grim, and strategies like the World Health Organization's expanded program on immunization need to be implemented. An elimination of HFMD in Guangdong might need a Herd Immunity Threshold of 78%.

  17. Teacher Research Programs = Increased Student Achievement

    Science.gov (United States)

    Dubner, J.

    2011-12-01

    Columbia University's Summer Research Program for Science Teachers (SRP), founded in 1990, is one of the largest, best known university professional development programs for science teachers in the U.S. For eight weeks in each of two consecutive summers, teachers participate as a member of a research team, led by a member of Columbia University's research faculty. In addition to the laboratory experience, all teachers meet weekly during the summer for a series of pedagogical activities to assist them in transferring the experience to their classrooms. The primary goal of the program is to provide K-12 science teachers with opportunities to work at the cutting edge of science and engineering, and thus to revitalize their teaching and help them to appreciate the use of inquiry-based methods in their classroom instruction. The secondary goals of the program are to give the pre-college teacher the ability to guide their students toward careers in science and engineering, to develop new teaching strategies, and to foster long-term scholarly collaborations. The last is especially important as it leads to a model of the teacher as active in science yet committed to the pre-college classroom. Since its inception, SRP has focused on an objective assessment of the program's impact on attitudes and instructional practices of participating teachers, on the performance of these teachers in their mentors' laboratories, and most importantly, on the impact of their participation in the program has on student interest and performance in science. Our research resulted in a paper published in the journal Science. SRP also facilitates a multi-site survey-based evaluation of other teacher research programs around the country. The author will present the findings of both studies.

  18. Evaluation of the Program Effectiveness of Research Competence Development in Prospective Elementary School Teachers

    Science.gov (United States)

    Khan, Natalya N.; Kolumbayeva, Sholpan Zh.; Karsybayeva, Raissa K.; Nabuova, Roza A.; Kurmanbekova, Manshuk B.; Syzdykbayeva, Aigul Dzh.

    2016-01-01

    To develop research competence in prospective teachers, a system of methods for diagnostics and formation of this competence in prospective elementary school teachers in the training process is designed. To diagnose the research competence, a series of techniques were used that allow subtle evaluation of each competence research component:…

  19. Towards an "International Forum for Teacher Educator Development": An Agenda for Research and Action

    Science.gov (United States)

    Kelchtermans, Geert; Smith, Kari; Vanderlinde, Ruben

    2018-01-01

    The outcomes of an international collaborative project are presented, involving experienced teacher educators and researchers from eight different countries, who engaged in a series of structured discussions on the professional development of teacher educators. We start with an overview of the needs in practice and policy, as well as the research…

  20. State Energy Data Report, 1991: Consumption estimates

    International Nuclear Information System (INIS)

    1993-05-01

    The State Energy Data Report (SEDR) provides annual time series estimates of State-level energy consumption by major economic sector. The estimates are developed in the State Energy Data System (SEDS), which is maintained and operated by the Energy Information Administration (EIA). The goal in maintaining SEDS is to create historical time series of energy consumption by State that are defined as consistently as possible over time and across sectors. SEDS exists for two principal reasons: (1) to provide State energy consumption estimates to the Government, policy makers, and the public; and (2) to provide the historical series necessary for EIA's energy models

  1. Modeling of Volatility with Non-linear Time Series Model

    OpenAIRE

    Kim Song Yon; Kim Mun Chol

    2013-01-01

    In this paper, non-linear time series models are used to describe volatility in financial time series data. To describe volatility, two of the non-linear time series are combined into form TAR (Threshold Auto-Regressive Model) with AARCH (Asymmetric Auto-Regressive Conditional Heteroskedasticity) error term and its parameter estimation is studied.

  2. Cross-correlation of long-range correlated series

    International Nuclear Information System (INIS)

    Arianos, Sergio; Carbone, Anna

    2009-01-01

    A method for estimating the cross-correlation C xy (τ) of long-range correlated series x(t) and y(t), at varying lags τ and scales n, is proposed. For fractional Brownian motions with Hurst exponents H 1 and H 2 , the asymptotic expression for C xy (τ) depends only on the lag τ (wide-sense stationarity) and scales as a power of n with exponent H 1 +H 2 for τ→0. The method is illustrated on: (i) financial series, to show the leverage effect; (ii) genomic sequences, to estimate the correlations between structural parameters along the chromosomes

  3. Breaking Ground: Analysis of the Assessment System and Impact of Mexico's Teacher Incentive Program "Carrera Magisterial." Technical Report. Summary

    Science.gov (United States)

    Santibariz, Lucrecia; Martinez, Jose Felipe; Datar, Ashlesha; McEwan, Patrick J.; Setodji, Claude Messan; Basurto-Davilao, Ricardo

    2007-01-01

    Mexico's Carrera Magisterial was instituted in 1992 and designed jointly by the federal education authorities, state authorities, and the teachers' union as a horizontal promotion system that rewards teachers with salary bonuses on the basis of their performance. Teacher performance is evaluated through a series of assessments, including teacher…

  4. Becoming a Reflective Mathematics Teacher: A Guide for Observations and Self-Assessment. Studies in Mathematical Thinking and Learning Series.

    Science.gov (United States)

    Artzt, Alice F.; Armour-Thomas, Eleanor

    This activity-oriented book for preservice mathematics teachers who are taking methods courses or who have been student teaching offers a framework for teacher reflection and self- assessment. It supplies detailed observation instruments for observing other teachers, reflective activities, and guidelines and instruments for supervisors. There are…

  5. Visibility graph approach to exchange rate series

    Science.gov (United States)

    Yang, Yue; Wang, Jianbo; Yang, Huijie; Mang, Jingshi

    2009-10-01

    By means of a visibility graph, we investigate six important exchange rate series. It is found that the series convert into scale-free and hierarchically structured networks. The relationship between the scaling exponents of the degree distributions and the Hurst exponents obeys the analytical prediction for fractal Brownian motions. The visibility graph can be used to obtain reliable values of Hurst exponents of the series. The characteristics are explained by using the multifractal structures of the series. The exchange rate of EURO to Japanese Yen is widely used to evaluate risk and to estimate trends in speculative investments. Interestingly, the hierarchies of the visibility graphs for the exchange rate series of these two currencies are significantly weak compared with that of the other series.

  6. Effective Professional Development for Physical Education Teachers: The Role of Informal, Collaborative Learning

    Science.gov (United States)

    Armour, Kathleen M.; Yelling, Martin

    2007-01-01

    This paper reports data from the third phase of a 2-year investigation into continuing professional development (CPD) for physical education teachers in England. The purpose of this phase was to examine the ways in which 10 case study teachers engaged in professional learning over the course of 1 academic year. Data were collected from a series of…

  7. Estimation of a noise level using coarse-grained entropy of experimental time series of internal pressure in a combustion engine

    International Nuclear Information System (INIS)

    Litak, Grzegorz; Taccani, Rodolfo; Radu, Robert; Urbanowicz, Krzysztof; HoIyst, Janusz A.; Wendeker, MirosIaw; Giadrossi, Alessandro

    2005-01-01

    We report our results on non-periodic experimental time series of pressure in a single cylinder spark ignition engine. The experiments were performed for different levels of loading. We estimate the noise level in internal pressure calculating the coarse-grained entropy from variations of maximal pressures in successive cycles. The results show that the dynamics of the combustion is a non-linear multidimensional process mediated by noise. Our results show that so defined level of noise in internal pressure is not monotonous function of loading

  8. Democracy in schools: are educators ready for teacher leadership?

    Directory of Open Access Journals (Sweden)

    Elsabé de Villiers

    2011-01-01

    Full Text Available The aim of this research was to determine educators' perceptions of and readiness for teacher leadership. A total of 283 educators in the Eden and Central Karoo Education District in the Western Cape participated in the study. The participants included district officials, principals, and members of school management teams, as well as veteran, middle, and novice educators. A series of instruments was used to determine educators' perspectives, perceptions and readiness for teacher leadership, including the Teacher Leadership Readiness Instrument (TLRI. The results indicated that educators held positive assumptions about teacher leadership. Educators' preliminary leadership perceptions, assumptions about and readiness for teacher leadership proved that the majority of educators are ready for a more distributed, deep democratic leadership practice in schools. Educators acknowledged the need for continuous professional development in the area of teacher leadership. It was also found that as preliminary leadership perceptions of educators improve or strengthen, readiness for teacher leadership is also likely to improve or strengthen. These findings have significant implications for leadership practices, collaboration, capacity-building and improvement in schools, educators' self-esteem, motivation and productivity, as well as student outcomes.

  9. Stochastic models for time series

    CERN Document Server

    Doukhan, Paul

    2018-01-01

    This book presents essential tools for modelling non-linear time series. The first part of the book describes the main standard tools of probability and statistics that directly apply to the time series context to obtain a wide range of modelling possibilities. Functional estimation and bootstrap are discussed, and stationarity is reviewed. The second part describes a number of tools from Gaussian chaos and proposes a tour of linear time series models. It goes on to address nonlinearity from polynomial or chaotic models for which explicit expansions are available, then turns to Markov and non-Markov linear models and discusses Bernoulli shifts time series models. Finally, the volume focuses on the limit theory, starting with the ergodic theorem, which is seen as the first step for statistics of time series. It defines the distributional range to obtain generic tools for limit theory under long or short-range dependences (LRD/SRD) and explains examples of LRD behaviours. More general techniques (central limit ...

  10. Pearson-Praxis Assessments Review Teacher Certification Assessment Technology Education: A Report for the Council on Technology and Engineering Teacher Education

    Science.gov (United States)

    Mahoney, Mark P.

    2015-01-01

    The Praxis Series, developed by Educational Testing Services (ETS), has been the long standing assessment for teacher licensure. It is comprised of three separate skills examinations: (1) Praxis Core Academic Skills for Educators (Core) (attempts to measure academic skills in reading, writing, and mathematics; content knowledge of candidates…

  11. Introduction to Hospitality and Tourism. Teacher Edition.

    Science.gov (United States)

    Walker, Susan S.

    This teacher's guide is the core publication of a series of instructional materials developed for the hospitality and tourism industry. It includes the entry-level competencies students will need to enter any of the occupational areas identified in the four cluster areas of the hospitality and tourism industry: lodging, food service, travel and…

  12. Sherlock Holmes' Smarter Great-Granddaughter. Teacher's Guide.

    Science.gov (United States)

    Kraft, D. Chetley; And Others

    This teacher's manual is designed to accompany the sixth grade level of the kindergarten through grade six sequenced literature curriculum developed through the Instructional Television Services Section of the Nebraska Department of Education. The purpose of the series at this level is to introduce the student to the wide variety in types of…

  13. Who chooses to become a teacher and why?

    DEFF Research Database (Denmark)

    Reimer, David; Dorf, Hans

    -secondary pupils. The nature of the data collected enables us to characterize teacher education students in contrast to a baseline reference group eligible to apply for teacher education and to compare these differences across countries (difference-in-differences estimation). This analytical strategy allows us......We analyze in this article to what extent beginning teacher education students at the primary school level differ with respect to previous educational pathways, socio-demographic characteristics, academic self-concepts and occupational motivations. In order to overcome methodological problems...... of most previous empirical studies on teacher recruitment we draw on data from a recent comparative study on teacher recruitment based on two different samples: In both Denmark and Finland we surveyed a representative group of first year teacher education students as well as last year upper...

  14. Foods: A Teacher's Guide to an Employment Orientation Course for Special Needs Students.

    Science.gov (United States)

    Grubb, Francine

    This teacher's guide on foods is one of a series of six designed for the employment orientation program for special needs students at the Gloucester County Vocational-Technical School in Sewell, New Jersey. The series includes laundry, hospitality, sewing, basic business, foods, and beauty culture. Each guide contains lesson plans consisting of…

  15. Elementary and Middle School Teacher Perceptions of Attention-Deficit/Hyperactivity Disorder Prevalence

    Science.gov (United States)

    Fabiano, Gregory A.; Pelham, William E., Jr.; Majumdar, Antara; Evans, Steven W.; Manos, Michael J.; Caserta, Donald; Girio-Herrera, Erin L.; Pisecco, Stewart; Hannah, Jane N.; Carter, Randy L.

    2013-01-01

    Background: Estimates of ADHD diagnosis and stimulant medication use vary across studies. Few studies ascertain the teacher perspective on these rates. Objective: To ascertain teachers' perceptions of ADHD prevalence and medication treatment within their classrooms. Method: The present school survey collected teacher report of identified children…

  16. State energy data report 1993: Consumption estimates

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-07-01

    The State Energy Data Report (SEDR) provides annual time series estimates of State-level energy consumption by major economic sector. The estimates are developed in the State Energy Data System (SEDS), which is maintained and operated by the Energy Information Administration (EIA). The goal in maintaining SEDS is to create historical time series of energy consumption by State that are defined as consistently as possible over time and across sectors. SEDS exists for two principal reasons: (1) to provide State energy consumption estimates to Members of Congress, Federal and State agencies, and the general public; and (2) to provide the historical series necessary for EIA`s energy models.

  17. Can a student learn optimally from two different teachers?

    International Nuclear Information System (INIS)

    Neirotti, J P

    2010-01-01

    We explore the effects of over-specificity in learning algorithms by investigating the behavior of a student, suited to learn optimally from a teacher B, learning from a teacher B' ≠ B. We only considered the supervised, on-line learning scenario with teachers selected from a particular family. We found that, in the general case, the application of the optimal algorithm to the wrong teacher produces a residual generalization error, even if the right teacher is harder. By imposing mild conditions to the learning algorithm form, we obtained an approximation for the residual generalization error. Simulations carried out in finite networks validate the estimate found.

  18. Bias correction of risk estimates in vaccine safety studies with rare adverse events using a self-controlled case series design.

    Science.gov (United States)

    Zeng, Chan; Newcomer, Sophia R; Glanz, Jason M; Shoup, Jo Ann; Daley, Matthew F; Hambidge, Simon J; Xu, Stanley

    2013-12-15

    The self-controlled case series (SCCS) method is often used to examine the temporal association between vaccination and adverse events using only data from patients who experienced such events. Conditional Poisson regression models are used to estimate incidence rate ratios, and these models perform well with large or medium-sized case samples. However, in some vaccine safety studies, the adverse events studied are rare and the maximum likelihood estimates may be biased. Several bias correction methods have been examined in case-control studies using conditional logistic regression, but none of these methods have been evaluated in studies using the SCCS design. In this study, we used simulations to evaluate 2 bias correction approaches-the Firth penalized maximum likelihood method and Cordeiro and McCullagh's bias reduction after maximum likelihood estimation-with small sample sizes in studies using the SCCS design. The simulations showed that the bias under the SCCS design with a small number of cases can be large and is also sensitive to a short risk period. The Firth correction method provides finite and less biased estimates than the maximum likelihood method and Cordeiro and McCullagh's method. However, limitations still exist when the risk period in the SCCS design is short relative to the entire observation period.

  19. Workplace Literacy Teacher Training: Strategies for Instruction.

    Science.gov (United States)

    Harrington, Lois G.; And Others

    These four learning guides comprise one of four packages in the Workplace Literacy Teacher Training series that provides information and skills necessary for the user to become a successful instructor in an effective workplace literacy program. The guides in this package focus on the skills at the heart of such programs--communication, reading,…

  20. Powerful Learning Experiences and Suzuki Music Teachers

    Science.gov (United States)

    Reuning-Hummel, Carrie; Meyer, Allison; Rowland, Gordon

    2016-01-01

    Powerful Learning Experiences (PLEs) of Suzuki music teachers were examined in this fifth study in a series. The definition of a PLE is: "Experiences that stand out in memory because of their high quality, their impact on one's thoughts and actions over time, and their transfer to a wide range of contexts and circumstances." Ten…

  1. Contradictions of Control, Part 1: Administrators and Teachers.

    Science.gov (United States)

    McNeil, Linda M.

    1988-01-01

    Bureaucratic controls are at war with educational goals in our school system. This disharmony drastically affects the teacher/student relationship. The first in a three-part series, this article summarizes complex ethnographic data from the report "Contradictions of Control: School Structure and School Knowledge." Includes 6 references. (MD)

  2. Masonry. Teacher's Guide. Building Maintenance Units of Instruction.

    Science.gov (United States)

    Barnes, Bill

    This teaching guide on masonry building maintenance, one in a series of six publications designed for building maintenance instructors in Texas, is designed to give students an understanding of masonry construction. Introductory material provides teachers with information on use of the units of instruction and personalization and localization of…

  3. Japanese EFL Teachers' Perceptions of Communicative, Audiolingual and Yakudoku Activities

    Directory of Open Access Journals (Sweden)

    Greta Gorsuch

    2001-03-01

    Full Text Available In recent years, the learning of English as a Foreign Language in Japanese high schools has become the focus of new educational policies applied at the national level. One of these is The Course of Study issue by the Ministry of Education, in which teachers are, for the first time in a long series of curriculum guidelines, adjured to develop students' "positive attitudes towards communicating in English." Another is the JET program, which has put thousands of native English speaking assistant language teachers (ALTs into Japanese secondary classrooms for the purpose of team teaching with Japanese teachers. Data resulting from a survey project of 876 Japanese high school English teachers was used to provide empirical evidence of teachers' levels of approval of communicative, audiolingual and traditional (yakudoku activities. Teachers were also asked to rate the strengths of a variety of influences on their instruction, including university entrance exams, and pre- and in-service teacher education programs. Teachers' perceptions of both activities and instructional influences were examined in light of teachers' length of career, type of school (private versus public, academic versus vocational, and level of contact with an ALT. The data revealed the complexities of imposing broad, national educational policies on a diverse group of teachers, and in an educational culture which likely precludes teachers' use of communicative activities.

  4. Initial and final estimates of the Bilinear seasonal time series model ...

    African Journals Online (AJOL)

    In getting the estimates of the parameters of this model special attention was paid to the problem of having good initial estimates as it is proposed that with good initial values of the parameters the estimates obtaining by the Newton-Raphson iterative technique usually not only converge but also are good estimates.

  5. Mathematics Teachers at Work: Connecting Curriculum Materials and Classroom Instruction. Studies in Mathematical Thinking and Learning Series

    Science.gov (United States)

    Remillard, Janine T., Ed.; Herbel-Eisenmann, Beth A., Ed.; Lloyd, Gwendolyn M., Ed.

    2011-01-01

    This book compiles and synthesizes existing research on teachers' use of mathematics curriculum materials and the impact of curriculum materials on teaching and teachers, with a particular emphasis on--but not restricted to--those materials developed in the 1990s in response to the NCTM's Principles and Standards for School Mathematics. Despite…

  6. State energy data report 1994: Consumption estimates

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-10-01

    This document provides annual time series estimates of State-level energy consumption by major economic sector. The estimates are developed in the State Energy Data System (SEDS), operated by EIA. SEDS provides State energy consumption estimates to members of Congress, Federal and State agencies, and the general public, and provides the historical series needed for EIA`s energy models. Division is made for each energy type and end use sector. Nuclear electric power is included.

  7. State energy data report 1994: Consumption estimates

    International Nuclear Information System (INIS)

    1996-10-01

    This document provides annual time series estimates of State-level energy consumption by major economic sector. The estimates are developed in the State Energy Data System (SEDS), operated by EIA. SEDS provides State energy consumption estimates to members of Congress, Federal and State agencies, and the general public, and provides the historical series needed for EIA's energy models. Division is made for each energy type and end use sector. Nuclear electric power is included

  8. Forecasting Long Memory Series Subject to Structural Change

    DEFF Research Database (Denmark)

    Dias, Gustavo Fruet; Papailias, Fotis

    A two-stage forecasting approach for long memory time series is introduced. In the first step we estimate the fractional exponent and, applying the fractional differencing operator, we obtain the underlying weakly dependent series. In the second step, we perform the multi-step ahead forecasts...... for the weakly dependent series and obtain their long memory counterparts by applying the fractional cumulation operator. The methodology applies to stationary and nonstationary cases. Simulations and an application to seven time series provide evidence that the new methodology is more robust to structural...... change and yields good forecasting results....

  9. 'Hidden poverty' of teachers: Status, consequences and overcoming strategies

    Directory of Open Access Journals (Sweden)

    Bogunović Blanka

    2008-01-01

    Full Text Available The consequences of reduced financial and other possibilities in the period of social transition are reflected on the quality of life and work of teachers, and thereby indirectly on education of pupils as well. Aims: (1 to determine teachers' estimation of their own financial status and subjective perception of teachers' poverty; (2 to examine in which way the personal perception of poverty of teachers is linked with the quality of their engagement in curricular and extracurricular activities; (3 to examine which economic and psychological strategies teachers use in overcoming stress because of the lower financial status; (4 to examine whether there are differences between teachers with regard to socio-demographic variables and the previously established goals. Sample consists of 141 teachers of music and general education schools in Belgrade and the interior of the country. Method: research is explorative and uses qualitative and psychometric methods of analysis. Results point out to the structure of 'hidden poverty' of teachers: average and poor financial status, financial and logistic support of the extended family, additional job, unfulfilled financial expectations regarding the educational status and ungratified higher needs. Teachers estimate that real poverty of educational system and 'hidden poverty' of teachers are reflected on the quality of certain aspects of educational process as a whole and in certain elements: teacher's personal life and work motivation, authority in school, quality of teacher's engagement in tuition and the possibility of professional specialization. Teachers use financial and psychological strategies for overcoming stress that can be determined as: moralist compensatory, evasive, inappropriate, emotional, relying on family and friendly supportive systems and activist. Conclusion: primarily subjective and spiritual impoverishment of the stratum of highly educated people, who are, in addition to this, the bearers

  10. Affirmative Action. Module Number 16. Work Experience Program Modules. Coordination Techniques Series.

    Science.gov (United States)

    Shawhan, Carl; Morley, Ray

    This self-instructional module, the last in a series of 16 on techniques for coordinating work experience programs, deals with affirmative action. Addressed in the module are the following topics: the nature of affirmative action legislation and regulations, the role of the teacher-coordinator as a resource person for affirmative action…

  11. The Hierarchical Spectral Merger Algorithm: A New Time Series Clustering Procedure

    KAUST Repository

    Euán, Carolina

    2018-04-12

    We present a new method for time series clustering which we call the Hierarchical Spectral Merger (HSM) method. This procedure is based on the spectral theory of time series and identifies series that share similar oscillations or waveforms. The extent of similarity between a pair of time series is measured using the total variation distance between their estimated spectral densities. At each step of the algorithm, every time two clusters merge, a new spectral density is estimated using the whole information present in both clusters, which is representative of all the series in the new cluster. The method is implemented in an R package HSMClust. We present two applications of the HSM method, one to data coming from wave-height measurements in oceanography and the other to electroencefalogram (EEG) data.

  12. Estimating return periods of extreme values from relatively short time series of winds

    Science.gov (United States)

    Jonasson, Kristjan; Agustsson, Halfdan; Rognvaldsson, Olafur; Arfeuille, Gilles

    2013-04-01

    An important factor for determining the prospect of individual wind farm sites is the frequency of extreme winds at hub height. Here, extreme winds are defined as the value of the highest 10 minutes averaged wind speed with a 50 year return period, i.e. annual exceeding probability of 2% (Rodrigo, 2010). A frequently applied method to estimate winds in the lowest few hundred meters above ground is to extrapolate observed 10-meter winds logarithmically to higher altitudes. Recent study by Drechsel et al. (2012) showed however that this methodology is not as accurate as interpolating simulated results from the global ECMWF numerical weather prediction (NWP) model to the desired height. Observations of persistent low level jets near Colima in SW-Mexico also show that the logarithmic approach can give highly inaccurate results for some regions (Arfeuille et al., 2012). To address these shortcomings of limited, and/or poorly representative, observations and extrapolations of winds one can use NWP models to dynamically scale down relatively coarse resolution atmospheric analysis. In the case of limited computing resources one has typically to make a compromise between spatial resolution and the duration of the simulated period, both of which can limit the quality of the wind farm siting. A common method to estimate maximum winds is to fit an extreme value distribution (e.g. Gumbel, gev or Pareto) to the maximum values of each year of available data, or the tail of these values. If data are only available for a short period, e.g. 10 or 15 years, then this will give a rather inaccurate estimate. It is possible to deal with this problem by utilizing monthly or weekly maxima, but this introduces new problems: seasonal variation, autocorrelation of neighboring values, and increased discrepancy between data and fitted distribution. We introduce a new method to estimate return periods of extreme values of winds at hub height from relatively short time series of winds, simulated

  13. Supporting Lesotho Teachers to Develop Resilience in the Face of the HIV and AIDS Pandemic

    Science.gov (United States)

    Wood, Lesley; Ntaote, Grace Makeletso; Theron, Linda

    2012-01-01

    HIV and AIDS threaten to erode the wellbeing of teachers who are faced with an increasing number of children rendered vulnerable by the pandemic. This article explores the usefulness of a supportive group intervention, Resilient Educators (REds), in supporting Lesotho teachers to respond to the HIV and AIDS-related challenges. A time-series pre-…

  14. FALSE DETERMINATIONS OF CHAOS IN SHORT NOISY TIME SERIES. (R828745)

    Science.gov (United States)

    A method (NEMG) proposed in 1992 for diagnosing chaos in noisy time series with 50 or fewer observations entails fitting the time series with an empirical function which predicts an observation in the series from previous observations, and then estimating the rate of divergenc...

  15. Automated Land Cover Change Detection and Mapping from Hidden Parameter Estimates of Normalized Difference Vegetation Index (NDVI) Time-Series

    Science.gov (United States)

    Chakraborty, S.; Banerjee, A.; Gupta, S. K. S.; Christensen, P. R.; Papandreou-Suppappola, A.

    2017-12-01

    Multitemporal observations acquired frequently by satellites with short revisit periods such as the Moderate Resolution Imaging Spectroradiometer (MODIS), is an important source for modeling land cover. Due to the inherent seasonality of the land cover, harmonic modeling reveals hidden state parameters characteristic to it, which is used in classifying different land cover types and in detecting changes due to natural or anthropogenic factors. In this work, we use an eight day MODIS composite to create a Normalized Difference Vegetation Index (NDVI) time-series of ten years. Improved hidden parameter estimates of the nonlinear harmonic NDVI model are obtained using the Particle Filter (PF), a sequential Monte Carlo estimator. The nonlinear estimation based on PF is shown to improve parameter estimation for different land cover types compared to existing techniques that use the Extended Kalman Filter (EKF), due to linearization of the harmonic model. As these parameters are representative of a given land cover, its applicability in near real-time detection of land cover change is also studied by formulating a metric that captures parameter deviation due to change. The detection methodology is evaluated by considering change as a rare class problem. This approach is shown to detect change with minimum delay. Additionally, the degree of change within the change perimeter is non-uniform. By clustering the deviation in parameters due to change, this spatial variation in change severity is effectively mapped and validated with high spatial resolution change maps of the given regions.

  16. Analysis of complex time series using refined composite multiscale entropy

    International Nuclear Information System (INIS)

    Wu, Shuen-De; Wu, Chiu-Wen; Lin, Shiou-Gwo; Lee, Kung-Yen; Peng, Chung-Kang

    2014-01-01

    Multiscale entropy (MSE) is an effective algorithm for measuring the complexity of a time series that has been applied in many fields successfully. However, MSE may yield an inaccurate estimation of entropy or induce undefined entropy because the coarse-graining procedure reduces the length of a time series considerably at large scales. Composite multiscale entropy (CMSE) was recently proposed to improve the accuracy of MSE, but it does not resolve undefined entropy. Here we propose a refined composite multiscale entropy (RCMSE) to improve CMSE. For short time series analyses, we demonstrate that RCMSE increases the accuracy of entropy estimation and reduces the probability of inducing undefined entropy.

  17. Electrical. Teacher's Guide. Building Maintenance Units of Instruction.

    Science.gov (United States)

    East Texas State Univ., Commerce. Occupational Curriculum Lab.

    This teaching guide on electrical building maintenance, one in a series of six publications designed for building maintenance instructors in Texas, is designed to give students an understanding of electricity in order to know how to make basic repairs to the electrical systems in a building. Introductory material provides teachers with information…

  18. Betting on Teachers: The 43rd Annual Phi Delta Kappa/Gallup Poll of the Public's Attitudes toward the Public Schools

    Science.gov (United States)

    Bushaw, William J.; Lopez, Shane J.

    2011-01-01

    This is the latest in a series of polls sponsored by Phi Delta Kappa International with the Gallup organization. Some important findings of this year's poll include: About half of us believe teacher unions are hurting public education, but we're more likely to support teacher union leaders than governors in disputes over teacher collective…

  19. Using Student Surveys to Monitor Teacher Effectiveness: Q&A with Dr. Ronald Ferguson. REL Mid-Atlantic Teacher Effectiveness Webinar Series

    Science.gov (United States)

    Regional Educational Laboratory Mid-Atlantic, 2013

    2013-01-01

    In this webinar, Dr. Ronald Ferguson, creator of the Tripod Project and Senior Lecturer at Harvard University Graduate School of Education, discussed the use of student surveys as an approach to measuring teacher effectiveness. This Q&A addressed the questions participants had for Dr. Ferguson following the webinar. The webinar recording and…

  20. A simulation study to quantify the impacts of exposure measurement error on air pollution health risk estimates in copollutant time-series models.

    Science.gov (United States)

    Dionisio, Kathie L; Chang, Howard H; Baxter, Lisa K

    2016-11-25

    Exposure measurement error in copollutant epidemiologic models has the potential to introduce bias in relative risk (RR) estimates. A simulation study was conducted using empirical data to quantify the impact of correlated measurement errors in time-series analyses of air pollution and health. ZIP-code level estimates of exposure for six pollutants (CO, NO x , EC, PM 2.5 , SO 4 , O 3 ) from 1999 to 2002 in the Atlanta metropolitan area were used to calculate spatial, population (i.e. ambient versus personal), and total exposure measurement error. Empirically determined covariance of pollutant concentration pairs and the associated measurement errors were used to simulate true exposure (exposure without error) from observed exposure. Daily emergency department visits for respiratory diseases were simulated using a Poisson time-series model with a main pollutant RR = 1.05 per interquartile range, and a null association for the copollutant (RR = 1). Monte Carlo experiments were used to evaluate the impacts of correlated exposure errors of different copollutant pairs. Substantial attenuation of RRs due to exposure error was evident in nearly all copollutant pairs studied, ranging from 10 to 40% attenuation for spatial error, 3-85% for population error, and 31-85% for total error. When CO, NO x or EC is the main pollutant, we demonstrated the possibility of false positives, specifically identifying significant, positive associations for copollutants based on the estimated type I error rate. The impact of exposure error must be considered when interpreting results of copollutant epidemiologic models, due to the possibility of attenuation of main pollutant RRs and the increased probability of false positives when measurement error is present.

  1. Screen Twice, Cut Once: Assessing the Predictive Validity of Teacher Selection Tools

    Science.gov (United States)

    Goldhaber, Dan; Grout, Cyrus; Huntington-Klein, Nick

    2015-01-01

    It is well documented that teachers can have profound effects on student outcomes. Empirical estimates find that a one standard deviation increase in teacher quality raises student test achievement by 10 to 25 percent of a standard deviation. More recent evidence shows that the effectiveness of teachers can affect long-term student outcomes, such…

  2. The Photoplethismographic Signal Processed with Nonlinear Time Series Analysis Tools

    International Nuclear Information System (INIS)

    Hernandez Caceres, Jose Luis; Hong, Rolando; Garcia Lanz, Abel; Garcia Dominguez, Luis; Cabannas, Karelia

    2001-01-01

    Finger photoplethismography (PPG) signals were submitted to nonlinear time series analysis. The applied analytical techniques were: (i) High degree polynomial fitting for baseline estimation; (ii) FFT analysis for estimating power spectra; (iii) fractal dimension estimation via the Higuchi's time-domain method, and (iv) kernel nonparametric estimation for reconstructing noise free-attractors and also for estimating signal's stochastic components

  3. Language in Education: Preservice teachers' ideas about grammar and knowledge about language

    DEFF Research Database (Denmark)

    Christensen, Mette Vedsgaard; Bock, Kathrin

    2012-01-01

    Even though the national curriculum for mother tongue instruction in Denmark emphasizes a functional view of language (Danish Ministry of Education, 2009), we - as teacher educators - have experienced that most of our teacher students’ notions about language and grammar are deeply rooted...... in a formal and structural view of language. Hence we designed and carried out an action research project with the aim of pushing first year teacher students’ notions about language in a more functional direction. Throughout their first year in teacher training the students were involved in a series...... of radical changes to the curriculum, such as introducing SFL-based linguistics (Halliday 1994) and genre theory (Martin & Rose 2008) as the overall theoretical framework for language description. These changes were made in order to equip future teachers with a more functional view on language...

  4. A Thousand Lights [and] A Thousand Lights: Teacher and Parent Guide. Brothers Series.

    Science.gov (United States)

    Benton, Hope

    This book for children (ages 8 to 14) and the accompanying teacher/parent guide present the story of two brothers, one of whom has a severe hearing impairment, who climb up Mt. Fuji in Japan. Information on the disability is presented subtly and incidentally to encourage the reader to relate more personally and foster a deeper level of acceptance…

  5. Clustering of financial time series

    Science.gov (United States)

    D'Urso, Pierpaolo; Cappelli, Carmela; Di Lallo, Dario; Massari, Riccardo

    2013-05-01

    This paper addresses the topic of classifying financial time series in a fuzzy framework proposing two fuzzy clustering models both based on GARCH models. In general clustering of financial time series, due to their peculiar features, needs the definition of suitable distance measures. At this aim, the first fuzzy clustering model exploits the autoregressive representation of GARCH models and employs, in the framework of a partitioning around medoids algorithm, the classical autoregressive metric. The second fuzzy clustering model, also based on partitioning around medoids algorithm, uses the Caiado distance, a Mahalanobis-like distance, based on estimated GARCH parameters and covariances that takes into account the information about the volatility structure of time series. In order to illustrate the merits of the proposed fuzzy approaches an application to the problem of classifying 29 time series of Euro exchange rates against international currencies is presented and discussed, also comparing the fuzzy models with their crisp version.

  6. Classroom interaction studies as a source for teacher competencies: towards research based competencies for teaching in multicultural schools

    NARCIS (Netherlands)

    Brok, den P.J.; Hajer, M.; Eerde, van H.A.A.

    2010-01-01

    Dealing with ethnic and linguistic diversity is one of the major challenges in today's education. Therefore, the formulation of competencies for teachers and teacher training should take into account the specific requirements of teaching in multicultural schools. In 2002, a series of small-scale

  7. A framework for consistent estimation of leaf area index, fraction of absorbed photosynthetically active radiation, and surface albedo from MODIS time-series data

    DEFF Research Database (Denmark)

    Xiao, Zhiqiang; Liang, Shunlin; Wang, Jindi

    2015-01-01

    -series MODerate Resolution Imaging Spectroradiometer (MODIS) surface reflectance data. If the reflectance data showed snow-free areas, an ensemble Kalman filter (EnKF) technique was used to estimate leaf area index (LAI) for a two-layer canopy reflectance model (ACRM) by combining predictions from a phenology...... model and the MODIS surface reflectance data. The estimated LAI values were then input into the ACRM to calculate the surface albedo and the fraction of absorbed photosynthetically active radiation (FAPAR). For snow-covered areas, the surface albedo was calculated as the underlying vegetation canopy...... albedo plus the weighted distance between the underlying vegetation canopy albedo and the albedo over deep snow. The LAI/FAPAR and surface albedo values estimated using this framework were compared with MODIS collection 5 eight-day 1-km LAI/FAPAR products (MOD15A2) and 500-m surface albedo product (MCD43...

  8. Effective School Leaders. Q&A with Eric A. Hanushek, Ph.D. REL Mid-Atlantic Teacher Effectiveness Webinar Series

    Science.gov (United States)

    Regional Educational Laboratory Mid-Atlantic, 2014

    2014-01-01

    This webinar on effective school leaders discussed the important relationship between a school's socio-economic status, school leadership, and teacher turnover rate. Participants explored the major role of school leaders in fostering teacher effectiveness and discussed strategies they can use at the local level to increase school leader…

  9. Evaluating the impact of a Biology I professional development series

    Science.gov (United States)

    Sampsell, Jacquelyn Scipper

    2005-11-01

    Effective professional development offers opportunities for teachers to reflect on their practices, modify and implement changes in the classroom, and eventually impact students' learning. However, professional development must be evaluated to determine whether the desired results are actually occurring in the classroom. The Program for Research and Evaluation for Public Schools, Inc. (PREPS) created a Biology I Workshop series to assist school districts in Mississippi in aligning curriculum, instruction, and assessment that will ultimately improve student achievement in the classroom and performance on the current high-stakes test. This study evaluated the PREPS Biology I Subject Area workshops by using Thomas Guskey's evaluation model as a guide for the process. This study used a mixed-method design and collected data from three primary sources: the PREPS Final Evaluation Form completed at the conclusion of workshops, a questionnaire created by the researcher, and interviews with six-case study teacher participants selected from the results of the questionnaire. According to the ratings and comments written on the two instruments and supporting evidence from the case-study teachers, the participants of the Biology I workshop found the workshops to be effective for all five levels of Guskey's evaluation model. The content was rated effective because the workshop materials were aligned to the curriculum frameworks and were focused on using student learning to improve student achievement. Working through the activities rather than simply being told about them and having a successful classroom biology teacher as a presenter were the factors that contributed to the increase in the participants' knowledge and skills. Organizational results indicate that the workshop was effective in that the goals of the workshop series aligned with the schools' mission and goals for student learning. Several issues, such as financial support, time for collaboration with peers, and

  10. Buscando Hallaras. Que Bonito Es Leer, II. Libro II. Guia Para el Maestro (Looking You Will Find. How Nice Reading Is, II. Book II. Teacher's Guide).

    Science.gov (United States)

    Dissemination and Assessment Center for Bilingual Education, Austin, TX.

    The teacher's manual, written in Spanish, is a detailed guide for using the reader and workbook of the same title. Taken together, the three books comprise the second level of a series of supplementary materials to teach reading in Spanish to second grade students. The teacher's guide contains an introduction explaining the series in its entirety,…

  11. Restructuring Teachers' Work

    Directory of Open Access Journals (Sweden)

    Lisa Kirtman

    2002-05-01

    the classroom organized to support and sustain classroom changes. Two of the three schools introduced changes in staff organization (teacher teams and leadership (governance committees, but under-estimated the professional development and other supports that would in turn support changes in classroom practice. Altogether, it appears unlikely that the observed changes in professional roles were sufficiently well established and connected to affect core educational practice in the long run.

  12. Resources to Meet the Educational Needs of Language Minorities: Teachers in Public Schools.

    Science.gov (United States)

    Waggoner, Dorothy

    Findings are presented from the Teachers Language Skills Survey, the first national survey undertaken to estimate how many teachers currently employed in public schools have the backgrounds, experience, education, and skills needed to teach students with limited-English proficiency. Information was gathered on teachers teaching in the 1976-77…

  13. A Time Series Forecasting Method

    Directory of Open Access Journals (Sweden)

    Wang Zhao-Yu

    2017-01-01

    Full Text Available This paper proposes a novel time series forecasting method based on a weighted self-constructing clustering technique. The weighted self-constructing clustering processes all the data patterns incrementally. If a data pattern is not similar enough to an existing cluster, it forms a new cluster of its own. However, if a data pattern is similar enough to an existing cluster, it is removed from the cluster it currently belongs to and added to the most similar cluster. During the clustering process, weights are learned for each cluster. Given a series of time-stamped data up to time t, we divide it into a set of training patterns. By using the weighted self-constructing clustering, the training patterns are grouped into a set of clusters. To estimate the value at time t + 1, we find the k nearest neighbors of the input pattern and use these k neighbors to decide the estimation. Experimental results are shown to demonstrate the effectiveness of the proposed approach.

  14. State energy data report 1995 - consumption estimates

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-01

    The State Energy Data Report (SEDR) provides annual time series estimates of State-level energy consumption by major economic sectors. The estimates are developed in the State Energy Data System (SEDS), which is maintained and operated by the Energy Information Administration (EIA). The goal in maintaining SEDS exists for two principal reasons: (1) to provide State energy consumption estimates to Members of Congress, Federal and State agencies, and the general public, and (2) to provide the historical series necessary for EIA`s energy models.

  15. Estimating urban vegetation fraction across 25 cities in pan-Pacific using Landsat time series data

    Science.gov (United States)

    Lu, Yuhao; Coops, Nicholas C.; Hermosilla, Txomin

    2017-04-01

    Urbanization globally is consistently reshaping the natural landscape to accommodate the growing human population. Urban vegetation plays a key role in moderating environmental impacts caused by urbanization and is critically important for local economic, social and cultural development. The differing patterns of human population growth, varying urban structures and development stages, results in highly varied spatial and temporal vegetation patterns particularly in the pan-Pacific region which has some of the fastest urbanization rates globally. Yet spatially-explicit temporal information on the amount and change of urban vegetation is rarely documented particularly in less developed nations. Remote sensing offers an exceptional data source and a unique perspective to map urban vegetation and change due to its consistency and ubiquitous nature. In this research, we assess the vegetation fractions of 25 cities across 12 pan-Pacific countries using annual gap-free Landsat surface reflectance products acquired from 1984 to 2012, using sub-pixel, spectral unmixing approaches. Vegetation change trends were then analyzed using Mann-Kendall statistics and Theil-Sen slope estimators. Unmixing results successfully mapped urban vegetation for pixels located in urban parks, forested mountainous regions, as well as agricultural land (correlation coefficient ranging from 0.66 to 0.77). The greatest vegetation loss from 1984 to 2012 was found in Shanghai, Tianjin, and Dalian in China. In contrast, cities including Vancouver (Canada) and Seattle (USA) showed stable vegetation trends through time. Using temporal trend analysis, our results suggest that it is possible to reduce noise and outliers caused by phenological changes particularly in cropland using dense new Landsat time series approaches. We conclude that simple yet effective approaches of unmixing Landsat time series data for assessing spatial and temporal changes of urban vegetation at regional scales can provide

  16. Understanding the importance of teachers in facilitating student success: Contemporary science, practice, and policy.

    Science.gov (United States)

    Jimerson, Shane R; Haddock, Aaron D

    2015-12-01

    Teacher quality has a vital influence on student success or failure. Thus, further research regarding teacher effectiveness, teacher evaluation, teacher well-being, and teacher contributions is essential to inform school psychologists and allied educational professionals who collaborate and consult with teachers to facilitate student success. In this special topic section of School Psychology Quarterly, a series of 6 articles further elucidate teachers' powerful contributions to student outcomes along with concrete, research-based ways for school psychologists to support and collaborate with teachers. The studies included in the special section describe how teacher support facilitates students' positive academic and social-emotional outcomes and how students' attitudes toward learning moderate the association between the classroom environment and students' academic achievement. Studies also report on the development and validation of self-report measures focused on both teacher subjective well-being and teachers' use of evidence-based practices. Finally, the articles included in the special topic section offer insights and ideas for refining teacher evaluation practices, understanding the factors contributing to program implementation fidelity, and improving prevention, early identification, and intervention efforts aimed at fostering school completion and positive youth development. (c) 2015 APA, all rights reserved).

  17. Evaluation of scaling invariance embedded in short time series.

    Directory of Open Access Journals (Sweden)

    Xue Pan

    Full Text Available Scaling invariance of time series has been making great contributions in diverse research fields. But how to evaluate scaling exponent from a real-world series is still an open problem. Finite length of time series may induce unacceptable fluctuation and bias to statistical quantities and consequent invalidation of currently used standard methods. In this paper a new concept called correlation-dependent balanced estimation of diffusion entropy is developed to evaluate scale-invariance in very short time series with length ~10(2. Calculations with specified Hurst exponent values of 0.2,0.3,...,0.9 show that by using the standard central moving average de-trending procedure this method can evaluate the scaling exponents for short time series with ignorable bias (≤0.03 and sharp confidential interval (standard deviation ≤0.05. Considering the stride series from ten volunteers along an approximate oval path of a specified length, we observe that though the averages and deviations of scaling exponents are close, their evolutionary behaviors display rich patterns. It has potential use in analyzing physiological signals, detecting early warning signals, and so on. As an emphasis, the our core contribution is that by means of the proposed method one can estimate precisely shannon entropy from limited records.

  18. Evaluation of scaling invariance embedded in short time series.

    Science.gov (United States)

    Pan, Xue; Hou, Lei; Stephen, Mutua; Yang, Huijie; Zhu, Chenping

    2014-01-01

    Scaling invariance of time series has been making great contributions in diverse research fields. But how to evaluate scaling exponent from a real-world series is still an open problem. Finite length of time series may induce unacceptable fluctuation and bias to statistical quantities and consequent invalidation of currently used standard methods. In this paper a new concept called correlation-dependent balanced estimation of diffusion entropy is developed to evaluate scale-invariance in very short time series with length ~10(2). Calculations with specified Hurst exponent values of 0.2,0.3,...,0.9 show that by using the standard central moving average de-trending procedure this method can evaluate the scaling exponents for short time series with ignorable bias (≤0.03) and sharp confidential interval (standard deviation ≤0.05). Considering the stride series from ten volunteers along an approximate oval path of a specified length, we observe that though the averages and deviations of scaling exponents are close, their evolutionary behaviors display rich patterns. It has potential use in analyzing physiological signals, detecting early warning signals, and so on. As an emphasis, the our core contribution is that by means of the proposed method one can estimate precisely shannon entropy from limited records.

  19. Sampling and estimating recreational use.

    Science.gov (United States)

    Timothy G. Gregoire; Gregory J. Buhyoff

    1999-01-01

    Probability sampling methods applicable to estimate recreational use are presented. Both single- and multiple-access recreation sites are considered. One- and two-stage sampling methods are presented. Estimation of recreational use is presented in a series of examples.

  20. FOURIER SERIES MODELS THROUGH TRANSFORMATION

    African Journals Online (AJOL)

    DEPT

    monthly temperature data (1996 – 2005) collected from the National Root ... KEY WORDS: Fourier series, square transformation, multiplicative model, ... fluctuations or movements are often periodic(Ekpeyong,2005). .... significant trend or not, if the trend is not significant, the grand mean may be used as an estimate of trend.

  1. Elements and Principles of Design Posters. Teacher's Guide.

    Science.gov (United States)

    1996

    This book accompanies a poster series and allows the teacher to pre-plan a lesson or activity for students with the objectives shown for each element or principle of design to be presented. Along with a black-and-white reproduction of each poster, major concepts are discussed. Suggested student activities relating to a particular element or…

  2. Development and application of a modified dynamic time warping algorithm (DTW-S) to analyses of primate brain expression time series.

    Science.gov (United States)

    Yuan, Yuan; Chen, Yi-Ping Phoebe; Ni, Shengyu; Xu, Augix Guohua; Tang, Lin; Vingron, Martin; Somel, Mehmet; Khaitovich, Philipp

    2011-08-18

    Comparing biological time series data across different conditions, or different specimens, is a common but still challenging task. Algorithms aligning two time series represent a valuable tool for such comparisons. While many powerful computation tools for time series alignment have been developed, they do not provide significance estimates for time shift measurements. Here, we present an extended version of the original DTW algorithm that allows us to determine the significance of time shift estimates in time series alignments, the DTW-Significance (DTW-S) algorithm. The DTW-S combines important properties of the original algorithm and other published time series alignment tools: DTW-S calculates the optimal alignment for each time point of each gene, it uses interpolated time points for time shift estimation, and it does not require alignment of the time-series end points. As a new feature, we implement a simulation procedure based on parameters estimated from real time series data, on a series-by-series basis, allowing us to determine the false positive rate (FPR) and the significance of the estimated time shift values. We assess the performance of our method using simulation data and real expression time series from two published primate brain expression datasets. Our results show that this method can provide accurate and robust time shift estimates for each time point on a gene-by-gene basis. Using these estimates, we are able to uncover novel features of the biological processes underlying human brain development and maturation. The DTW-S provides a convenient tool for calculating accurate and robust time shift estimates at each time point for each gene, based on time series data. The estimates can be used to uncover novel biological features of the system being studied. The DTW-S is freely available as an R package TimeShift at http://www.picb.ac.cn/Comparative/data.html.

  3. Common Core State Standards and Teacher Effectiveness. Q&A with Ross Wiener, Ph.D. REL Mid-Atlantic Teacher Effectiveness Webinar Series

    Science.gov (United States)

    Regional Educational Laboratory Mid-Atlantic, 2013

    2013-01-01

    In this REL Mid-Atlantic webinar, Dr. Ross Wiener, Vice President and Executive Director of the Education and Society Program, Aspen Institute, discussed strategies for integrating the Common Core State Standards (CCSS) into teacher effectiveness systems, including ways in which the CCSS can support professional growth and inform teacher…

  4. Asymptotic behaviour of a rescattering series for nonlinear reggeons

    International Nuclear Information System (INIS)

    Akkelin, S.V.; Martynov, E.S.

    1990-01-01

    A series of elastic re-scattering (both quasi-eikonal and U-matrix ones) for reggeons with nonlinear trajectories are estimated asymptotically. The calculations are performed for models of supercritical and dipole pomerons. A weak dependence of the series of re-scattering on reggeon trajectory nonlinearity is revealed. 13 refs.; 3 figs

  5. Where Have All the Skeptics Gone? Patterns of New Age Beliefs and Anti-scientific Attitudes in Preservice Primary Teachers.

    Science.gov (United States)

    Yates, Gregory C. R.; Chandler, Margaret

    2001-01-01

    Questions whether belief in the paranormal is alive and well in preservice teachers. Studies undergraduate preservice teachers' (n=232) reactions to a series of eight statements reflecting paranormal New Age beliefs rated earlier by a faculty panel as "totally unbelievable." (Contains 29 references.) (Author/YDS)

  6. Unawareness to Production, Dropout to Innovator--Primary Teachers' Understanding and Use of a Science, Technology and Society Approach to Science Teaching

    Science.gov (United States)

    Rollnick, Marissa; Dlamini, Betty T.; Bradley, John

    2015-01-01

    This paper investigates the process of teacher change in a group of 8 primary school teachers during their exposure to a science, technology and society (STS) approach to teaching Science in Swaziland. The research aimed to establish the effect of support given to teachers in using the approach through a series of workshops, followed by a 5-week…

  7. How pupils percieve the teacher's motivational techniques?

    Directory of Open Access Journals (Sweden)

    Bodroža Bojana

    2015-01-01

    Full Text Available Current research in the field of education indicates that the behaviour of the teacher affects significantly the quality and level of the pupil's motivation. The aim of our research was to determine the structure of the motivational style of teachers seen from the pupils' perspective, and to find out whether the pupils' perceptions of the teacher's motivational style depend upon cultural-educational influences of the family, and some characteristics of the students (academic achievements, gender. The sample included 856 pupils from 40 elementary schools in Serbia. We used the questionnaire with Likert's scale to obtain the evaluation of the teachers' behaviours. By the factor analysis we extracted three components of the teacher' behaviour: stimulating pupils' interest and competences, de-motivational teachers' behaviours and stimulating freedom of thinking and expression. The results show that the pupils whose parents have lower levels of education think that the behaviour of the teachers is directed to stimulating interest and competencies, as well as freedom of thinking and speech than the pupils of the parents of higher educational status. The control of the influence of the education of parents showed that the pupils of lower academic achievement perceive the teacher's behaviour as de-motivational. Compared to girls boys estimate more highly that teachers stimulate their interests and competencies. A suggestion is offered how a teacher should develop a behavioural style which would positively influence the quality of the pupils' motivation.

  8. Exercise: Benefits for Body and Mind. Teacher's Guide. Health Promotion for Adult Literacy Students: An Empowering Approach.

    Science.gov (United States)

    Hudson River Center for Program Development, Glenmont, NY.

    This teaching guide is part of a series of materials developed, with input from adult learners, to aid adult literacy teachers in incorporating health education into the curriculum. This guide aims to help teachers to provide adult students with information about good fitness habits and positive health behaviors that will substantially reduce the…

  9. Spectral Unmixing Analysis of Time Series Landsat 8 Images

    Science.gov (United States)

    Zhuo, R.; Xu, L.; Peng, J.; Chen, Y.

    2018-05-01

    Temporal analysis of Landsat 8 images opens up new opportunities in the unmixing procedure. Although spectral analysis of time series Landsat imagery has its own advantage, it has rarely been studied. Nevertheless, using the temporal information can provide improved unmixing performance when compared to independent image analyses. Moreover, different land cover types may demonstrate different temporal patterns, which can aid the discrimination of different natures. Therefore, this letter presents time series K-P-Means, a new solution to the problem of unmixing time series Landsat imagery. The proposed approach is to obtain the "purified" pixels in order to achieve optimal unmixing performance. The vertex component analysis (VCA) is used to extract endmembers for endmember initialization. First, nonnegative least square (NNLS) is used to estimate abundance maps by using the endmember. Then, the estimated endmember is the mean value of "purified" pixels, which is the residual of the mixed pixel after excluding the contribution of all nondominant endmembers. Assembling two main steps (abundance estimation and endmember update) into the iterative optimization framework generates the complete algorithm. Experiments using both simulated and real Landsat 8 images show that the proposed "joint unmixing" approach provides more accurate endmember and abundance estimation results compared with "separate unmixing" approach.

  10. Robust Forecasting of Non-Stationary Time Series

    OpenAIRE

    Croux, C.; Fried, R.; Gijbels, I.; Mahieu, K.

    2010-01-01

    This paper proposes a robust forecasting method for non-stationary time series. The time series is modelled using non-parametric heteroscedastic regression, and fitted by a localized MM-estimator, combining high robustness and large efficiency. The proposed method is shown to produce reliable forecasts in the presence of outliers, non-linearity, and heteroscedasticity. In the absence of outliers, the forecasts are only slightly less precise than those based on a localized Least Squares estima...

  11. Trend Change Detection in NDVI Time Series: Effects of Inter-Annual Variability and Methodology

    Science.gov (United States)

    Forkel, Matthias; Carvalhais, Nuno; Verbesselt, Jan; Mahecha, Miguel D.; Neigh, Christopher S.R.; Reichstein, Markus

    2013-01-01

    Changing trends in ecosystem productivity can be quantified using satellite observations of Normalized Difference Vegetation Index (NDVI). However, the estimation of trends from NDVI time series differs substantially depending on analyzed satellite dataset, the corresponding spatiotemporal resolution, and the applied statistical method. Here we compare the performance of a wide range of trend estimation methods and demonstrate that performance decreases with increasing inter-annual variability in the NDVI time series. Trend slope estimates based on annual aggregated time series or based on a seasonal-trend model show better performances than methods that remove the seasonal cycle of the time series. A breakpoint detection analysis reveals that an overestimation of breakpoints in NDVI trends can result in wrong or even opposite trend estimates. Based on our results, we give practical recommendations for the application of trend methods on long-term NDVI time series. Particularly, we apply and compare different methods on NDVI time series in Alaska, where both greening and browning trends have been previously observed. Here, the multi-method uncertainty of NDVI trends is quantified through the application of the different trend estimation methods. Our results indicate that greening NDVI trends in Alaska are more spatially and temporally prevalent than browning trends. We also show that detected breakpoints in NDVI trends tend to coincide with large fires. Overall, our analyses demonstrate that seasonal trend methods need to be improved against inter-annual variability to quantify changing trends in ecosystem productivity with higher accuracy.

  12. Is the Grass Greener? Current and Former Music Teachers' Perceptions a Year after Moving to a Different School or Leaving the Classroom

    Science.gov (United States)

    Hancock, Carl B.

    2016-01-01

    This study is the fourth in a series investigating the retention and turnover of music teachers using nationally representative data from the National Center for Educational Statistics. I identified records for music teachers in the Teacher Follow-Up Survey and determined how they viewed their careers one year after moving to a different school or…

  13. Are preservice teachers prepared to teach struggling readers?

    Science.gov (United States)

    Washburn, Erin K; Joshi, R Malatesha; Binks Cantrell, Emily

    2011-06-01

    Reading disabilities such as dyslexia, a specific learning disability that affects an individual's ability to process written language, are estimated to affect 15-20% of the general population. Consequently, elementary school teachers encounter students who struggle with inaccurate or slow reading, poor spelling, poor writing, and other language processing difficulties. However, recent evidence may suggest that teacher preparation programs are not providing preservice teachers with information about basic language constructs and other components related to scientifically based reading instruction. As a consequence preservice teachers have not exhibited explicit knowledge of such concepts in previous studies. Few studies have sought to assess preservice teachers' knowledge about dyslexia in conjunction with knowledge of basic language concepts. The purpose of the present study was to examine elementary school preservice teachers' knowledge of basic language constructs and their perceptions and knowledge about dyslexia. Findings from the present study suggest that preservice teachers, on average, are able to display implicit skills related to certain basic language constructs (i.e., syllable counting), but fail to demonstrate explicit knowledge of others (i.e., phonics principles). Also, preservice teachers seem to hold the common misconception that dyslexia is a visual perception deficit rather than a problem with phonological processing. Implications for future research as well as teacher preparation are discussed.

  14. The Best of Works4Me: Winning Tips from Classroom Teachers. NEA Checklist Series.

    Science.gov (United States)

    National Education Association, Washington, DC.

    This book presents a collection of tips focused around six themes. In "Teaching Techniques," teachers share ways in which they have increased their effectiveness and enhanced their interaction with students. "Content" provides methods of delivering art, science, reading, and other subjects in ways that will inspire and motivate…

  15. Hierarchical Hidden Markov Models for Multivariate Integer-Valued Time-Series

    DEFF Research Database (Denmark)

    Catania, Leopoldo; Di Mari, Roberto

    2018-01-01

    We propose a new flexible dynamic model for multivariate nonnegative integer-valued time-series. Observations are assumed to depend on the realization of two additional unobserved integer-valued stochastic variables which control for the time-and cross-dependence of the data. An Expectation......-Maximization algorithm for maximum likelihood estimation of the model's parameters is derived. We provide conditional and unconditional (cross)-moments implied by the model, as well as the limiting distribution of the series. A Monte Carlo experiment investigates the finite sample properties of our estimation...

  16. Quantifying Selection with Pool-Seq Time Series Data.

    Science.gov (United States)

    Taus, Thomas; Futschik, Andreas; Schlötterer, Christian

    2017-11-01

    Allele frequency time series data constitute a powerful resource for unraveling mechanisms of adaptation, because the temporal dimension captures important information about evolutionary forces. In particular, Evolve and Resequence (E&R), the whole-genome sequencing of replicated experimentally evolving populations, is becoming increasingly popular. Based on computer simulations several studies proposed experimental parameters to optimize the identification of the selection targets. No such recommendations are available for the underlying parameters selection strength and dominance. Here, we introduce a highly accurate method to estimate selection parameters from replicated time series data, which is fast enough to be applied on a genome scale. Using this new method, we evaluate how experimental parameters can be optimized to obtain the most reliable estimates for selection parameters. We show that the effective population size (Ne) and the number of replicates have the largest impact. Because the number of time points and sequencing coverage had only a minor effect, we suggest that time series analysis is feasible without major increase in sequencing costs. We anticipate that time series analysis will become routine in E&R studies. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  17. Towards a High Quality High School Workforce: A Longitudinal, Demographic Analysis of U.S. Public School Physics Teachers

    Science.gov (United States)

    Rushton, Gregory T.; Rosengrant, David; Dewar, Andrew; Shah, Lisa; Ray, Herman E.; Sheppard, Keith; Watanabe, Lynn

    2017-01-01

    Efforts to improve the number and quality of the high school physics teaching workforce have taken several forms, including those sponsored by professional organizations. Using a series of large-scale teacher demographic data sets from the National Center for Education Statistics (NCES), this study sought to investigate trends in teacher quality…

  18. Cross-Country Evidence on Teacher Performance Pay. Program on Education Policy and Governance Working Papers Series. PEPG 10-11

    Science.gov (United States)

    Woessmann, Ludger

    2010-01-01

    The general-equilibrium effects of performance-related teacher pay include long-term incentive and teacher-sorting mechanisms that usually elude experimental studies but are captured in cross-country comparisons. Combining country-level performance-pay measures with rich PISA-2003 international achievement microdata, this paper estimates…

  19. Building Chaotic Model From Incomplete Time Series

    Science.gov (United States)

    Siek, Michael; Solomatine, Dimitri

    2010-05-01

    This paper presents a number of novel techniques for building a predictive chaotic model from incomplete time series. A predictive chaotic model is built by reconstructing the time-delayed phase space from observed time series and the prediction is made by a global model or adaptive local models based on the dynamical neighbors found in the reconstructed phase space. In general, the building of any data-driven models depends on the completeness and quality of the data itself. However, the completeness of the data availability can not always be guaranteed since the measurement or data transmission is intermittently not working properly due to some reasons. We propose two main solutions dealing with incomplete time series: using imputing and non-imputing methods. For imputing methods, we utilized the interpolation methods (weighted sum of linear interpolations, Bayesian principle component analysis and cubic spline interpolation) and predictive models (neural network, kernel machine, chaotic model) for estimating the missing values. After imputing the missing values, the phase space reconstruction and chaotic model prediction are executed as a standard procedure. For non-imputing methods, we reconstructed the time-delayed phase space from observed time series with missing values. This reconstruction results in non-continuous trajectories. However, the local model prediction can still be made from the other dynamical neighbors reconstructed from non-missing values. We implemented and tested these methods to construct a chaotic model for predicting storm surges at Hoek van Holland as the entrance of Rotterdam Port. The hourly surge time series is available for duration of 1990-1996. For measuring the performance of the proposed methods, a synthetic time series with missing values generated by a particular random variable to the original (complete) time series is utilized. There exist two main performance measures used in this work: (1) error measures between the actual

  20. An Exploration of Prospective Teachers' Learning of Clinical Interview Techniques

    Science.gov (United States)

    Groth, Randall E.; Bergner, Jennifer A.; Burgess, Claudia R.

    2016-01-01

    The present study followed four prospective teachers through the process of learning to interview during an undergraduate research project experience. Participants conducted and video recorded a series of interviews with children. They also carried out guided analyses of the videos and written artefacts from the interviews to formulate conjectures…

  1. Finite mixture model: A maximum likelihood estimation approach on time series data

    Science.gov (United States)

    Yen, Phoong Seuk; Ismail, Mohd Tahir; Hamzah, Firdaus Mohamad

    2014-09-01

    Recently, statistician emphasized on the fitting of finite mixture model by using maximum likelihood estimation as it provides asymptotic properties. In addition, it shows consistency properties as the sample sizes increases to infinity. This illustrated that maximum likelihood estimation is an unbiased estimator. Moreover, the estimate parameters obtained from the application of maximum likelihood estimation have smallest variance as compared to others statistical method as the sample sizes increases. Thus, maximum likelihood estimation is adopted in this paper to fit the two-component mixture model in order to explore the relationship between rubber price and exchange rate for Malaysia, Thailand, Philippines and Indonesia. Results described that there is a negative effect among rubber price and exchange rate for all selected countries.

  2. Permutation entropy of finite-length white-noise time series.

    Science.gov (United States)

    Little, Douglas J; Kane, Deb M

    2016-08-01

    Permutation entropy (PE) is commonly used to discriminate complex structure from white noise in a time series. While the PE of white noise is well understood in the long time-series limit, analysis in the general case is currently lacking. Here the expectation value and variance of white-noise PE are derived as functions of the number of ordinal pattern trials, N, and the embedding dimension, D. It is demonstrated that the probability distribution of the white-noise PE converges to a χ^{2} distribution with D!-1 degrees of freedom as N becomes large. It is further demonstrated that the PE variance for an arbitrary time series can be estimated as the variance of a related metric, the Kullback-Leibler entropy (KLE), allowing the qualitative N≫D! condition to be recast as a quantitative estimate of the N required to achieve a desired PE calculation precision. Application of this theory to statistical inference is demonstrated in the case of an experimentally obtained noise series, where the probability of obtaining the observed PE value was calculated assuming a white-noise time series. Standard statistical inference can be used to draw conclusions whether the white-noise null hypothesis can be accepted or rejected. This methodology can be applied to other null hypotheses, such as discriminating whether two time series are generated from different complex system states.

  3. Outlier detection algorithms for least squares time series regression

    DEFF Research Database (Denmark)

    Johansen, Søren; Nielsen, Bent

    We review recent asymptotic results on some robust methods for multiple regression. The regressors include stationary and non-stationary time series as well as polynomial terms. The methods include the Huber-skip M-estimator, 1-step Huber-skip M-estimators, in particular the Impulse Indicator Sat...

  4. Finnish Cooperating Physics Teachers' Conceptions of Physics Teachers' Teacher Knowledge

    Science.gov (United States)

    Asikainen, Mervi A.; Hirvonen, Pekka E.

    2010-01-01

    This article examines Finnish cooperating physics teachers' conceptions of teacher knowledge in physics. Six experienced teachers were interviewed. The data was analyzed to form categories concerning the basis of teacher knowledge, and the tradition of German Didaktik and Shulman's theory of teacher knowledge were used in order to understand the…

  5. Assessing Coupling Dynamics from an Ensemble of Time Series

    Directory of Open Access Journals (Sweden)

    Germán Gómez-Herrero

    2015-04-01

    Full Text Available Finding interdependency relations between time series provides valuable knowledge about the processes that generated the signals. Information theory sets a natural framework for important classes of statistical dependencies. However, a reliable estimation from information-theoretic functionals is hampered when the dependency to be assessed is brief or evolves in time. Here, we show that these limitations can be partly alleviated when we have access to an ensemble of independent repetitions of the time series. In particular, we gear a data-efficient estimator of probability densities to make use of the full structure of trial-based measures. By doing so, we can obtain time-resolved estimates for a family of entropy combinations (including mutual information, transfer entropy and their conditional counterparts, which are more accurate than the simple average of individual estimates over trials. We show with simulated and real data generated by coupled electronic circuits that the proposed approach allows one to recover the time-resolved dynamics of the coupling between different subsystems.

  6. Numbers and Measuring, Learning With TOR: MINNEMAST Coordinated Mathematics - Science Series, Unit 16.

    Science.gov (United States)

    Vogt, Elaine E., Ed.

    This volume is the sixteenth in a series of 29 coordinated MINNEMAST units in mathematics and science for kindergarten and the primary grades. Intended for use by second-grade teachers, this unit guide provides a summary and overview of the unit, a list of materials needed, and descriptions of five groups of lessons. The purposes and procedures…

  7. Development and application of a modified dynamic time warping algorithm (DTW-S to analyses of primate brain expression time series

    Directory of Open Access Journals (Sweden)

    Vingron Martin

    2011-08-01

    Full Text Available Abstract Background Comparing biological time series data across different conditions, or different specimens, is a common but still challenging task. Algorithms aligning two time series represent a valuable tool for such comparisons. While many powerful computation tools for time series alignment have been developed, they do not provide significance estimates for time shift measurements. Results Here, we present an extended version of the original DTW algorithm that allows us to determine the significance of time shift estimates in time series alignments, the DTW-Significance (DTW-S algorithm. The DTW-S combines important properties of the original algorithm and other published time series alignment tools: DTW-S calculates the optimal alignment for each time point of each gene, it uses interpolated time points for time shift estimation, and it does not require alignment of the time-series end points. As a new feature, we implement a simulation procedure based on parameters estimated from real time series data, on a series-by-series basis, allowing us to determine the false positive rate (FPR and the significance of the estimated time shift values. We assess the performance of our method using simulation data and real expression time series from two published primate brain expression datasets. Our results show that this method can provide accurate and robust time shift estimates for each time point on a gene-by-gene basis. Using these estimates, we are able to uncover novel features of the biological processes underlying human brain development and maturation. Conclusions The DTW-S provides a convenient tool for calculating accurate and robust time shift estimates at each time point for each gene, based on time series data. The estimates can be used to uncover novel biological features of the system being studied. The DTW-S is freely available as an R package TimeShift at http://www.picb.ac.cn/Comparative/data.html.

  8. Multilevel Confirmatory Factor Analysis of the Teacher My Class Inventory-Short Form

    Science.gov (United States)

    Villares, Elizabeth; Mariani, Melissa; Sink, Christopher A.; Colvin, Kimberly

    2016-01-01

    Researchers analyzed data from elementary teachers (N = 233) to further establish the psychometric soundness of the Teacher My Class Inventory-Short Form. Supporting previous psychometric research, confirmatory factor analyses findings supported the factorial validity of the hypothesized five-factor solution. Internal reliability estimates were…

  9. Personal file: saved roles of a teacher telling stories

    Directory of Open Access Journals (Sweden)

    Antonia Simone Gomes

    2016-04-01

    Full Text Available Working with personal archives of teachers has expanded the ways to realize professional careers and allows visibility of pedagogical practices developed in the daily school. The aim of this paper is to understand the school relationships that go beyond the classroom and open up possibilities for the pedagogical practices in public schools in Minas Gerais in the century XX. It was used documents, personal writings, photographs and a series of records about professional career of Djanira Vaz Pereira, a teacher-former director of the Melo Viana School. The storage of documents suggests more than a systematic concern for the preservation of the academic past, appears to make sense of this constitutive material itself, which has in the dialogue between building self-image and scenes of daily professional work. The study takes us design our eye on the place and the importance of working with personal archives of teachers that make their own records, a legacy to understand education. Keywords: Personal Archive; Autobiographical Writing; Teachers Archive.

  10. A Tripartite Model of EFL Teacher Attributions, Burnout, and Self-Regulation: Toward the Prospects of Effective Teaching

    Science.gov (United States)

    Ghanizadeh, Afsaneh; Ghonsooly, Behzad

    2014-01-01

    The present study aims at delving into English as foreign language teachers' attributions by investigating the role of teacher attributions in teacher burnout and teacher self-regulation. This is accomplished by building a causal structural model through which the associations among these constructs are estimated. The results demonstrate that…

  11. How Teacher Turnover Harms Student Achievement. NBER Working Paper No. 17176

    Science.gov (United States)

    Ronfeldt, Matthew; Lankford, Hamilton; Loeb, Susanna; Wyckoff, James

    2011-01-01

    Researchers and policymakers often assume that teacher turnover harms student achievement, but recent evidence calls into question this assumption. Using a unique identification strategy that employs grade-level turnover and two classes of fixed-effects models, this study estimates the effects of teacher turnover on over 600,000 New York City 4th…

  12. Teacher-to-Teacher Mentoring. For Tech Teachers

    Science.gov (United States)

    Gora, Kathleen; Hinson, Janice

    2004-01-01

    Many principals want to provide effective professional development to assist teachers with technology integration, but they don't know where to begin. Sometimes teachers participate in professional development opportunities offered by local school districts, but these one-size-fits-all experiences seldom address teachers' specific needs or skill…

  13. Inferring interdependencies from short time series

    Indian Academy of Sciences (India)

    Abstract. Complex networks provide an invaluable framework for the study of interlinked dynamical systems. In many cases, such networks are constructed from observed time series by first estimating the ...... does not quantify causal relations (unlike IOTA, or .... Africa_map_regions.svg, which is under public domain.

  14. Local normalization: Uncovering correlations in non-stationary financial time series

    Science.gov (United States)

    Schäfer, Rudi; Guhr, Thomas

    2010-09-01

    The measurement of correlations between financial time series is of vital importance for risk management. In this paper we address an estimation error that stems from the non-stationarity of the time series. We put forward a method to rid the time series of local trends and variable volatility, while preserving cross-correlations. We test this method in a Monte Carlo simulation, and apply it to empirical data for the S&P 500 stocks.

  15. Extreme quantile estimation for dependent data with applications to finance

    OpenAIRE

    Drees, Holger

    2002-01-01

    The asymptotic normality of a class of estimators for extreme quantiles is established under mild structural conditions on the observed stationary \\beta-mixing time series. Consistent estimators of the asymptotic variance are introduced, which render possible the construction of asymptotic confidence intervals for the extreme quantiles. Moreover, it is shown that many well-known time series models satisfy our conditions. Then the theory is applied to a time series of returns of a stock in...

  16. Time-Series Adaptive Estimation of Vaccination Uptake Using Web Search Queries

    DEFF Research Database (Denmark)

    Dalum Hansen, Niels; Mølbak, Kåre; Cox, Ingemar J.

    2017-01-01

    Estimating vaccination uptake is an integral part of ensuring public health. It was recently shown that vaccination uptake can be estimated automatically from web data, instead of slowly collected clinical records or population surveys [2]. All prior work in this area assumes that features of vac...

  17. ICT AND TEACHERS' PERFORMANCE IN TERMS OF LESSON ...

    African Journals Online (AJOL)

    PROF. BARTH EKWEME

    Delivery Questionnaire (ICTTPLIDO) Developed by the researcher. The reliability estimate of ... teachers' performance in lesson preparation and delivery through the use of Information and ... information to accomplish the task, and evaluating ...

  18. The relationship between physical activity and work ability - A cross-sectional study of teachers.

    Science.gov (United States)

    Grabara, Małgorzata; Nawrocka, Agnieszka; Powerska-Didkowska, Aneta

    2018-01-01

    To assess relationship between physical activity (PA) and perceived work ability amongst teachers from the Upper Silesia, Poland. The study involved 171 teachers (129 women, 42 men) of primary and secondary schools of the Upper Silesia, Poland. Physical education teachers were excluded from the study. The level of PA was estimated using the International Physical Activity Questionnaire short version, and perceived work ability was estimated using Work Ability Index (WAI). Male teachers had significantly higher levels of vigorous-intensity PA, moderateintensity PA, and total weekly PA than female teachers. The recommendations of the World Health Organization (WHO) met 46% of studied women and 74% of men. Work ability did not differ between male and female teachers. Work ability was related to age, body mass index (BMI), and PA (vigorous-intensity PA, moderate-intensity PA, total weekly PA). The female teachers with excellent or good WAI had significantly higher levels of vigorous-intensity PA, moderate-intensity PA and total weekly PA than female teachers with moderate or poor WAI. The teachers involving in high or moderate intensity PA could improve their work ability. Further studies should focus on relation between physical activity and work ability among teachers of various age and seniority, from both, urban and rural schools. Int J Occup Med Environ Health 2018;31(1):1-9. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

  19. Exploring Mechanisms of Effective Teacher Coaching: A Tale of Two Cohorts From a Randomized Experiment

    Science.gov (United States)

    Blazar, David; Kraft, Matthew A.

    2015-01-01

    Although previous research has shown that teacher coaching can improve teaching practices and student achievement, little is known about specific features of effective coaching programs. We estimate the impact of MATCH Teacher Coaching (MTC) on a range of teacher practices using a blocked randomized trial and explore how changes in the coaching…

  20. A Model for Teacher Effects from Longitudinal Data without Assuming Vertical Scaling

    Science.gov (United States)

    Mariano, Louis T.; McCaffrey, Daniel F.; Lockwood, J. R.

    2010-01-01

    There is an increasing interest in using longitudinal measures of student achievement to estimate individual teacher effects. Current multivariate models assume each teacher has a single effect on student outcomes that persists undiminished to all future test administrations (complete persistence [CP]) or can diminish with time but remains…

  1. Integrating Mobile Phones into Teaching and Learning: A Case Study of Teacher Training through Professional Development Workshops

    Science.gov (United States)

    Ekanayake, Sakunthala Y.; Wishart, Jocelyn

    2015-01-01

    This paper presents the development and implementation of a professional development workshop series on integrating mobile phones into science teaching for a group of teachers in Sri Lanka. The series comprised a 3-day Planning Workshop followed by implementation of the planned lessons in real classrooms and a subsequent 1-day Reviewing Workshop.…

  2. Interdisciplinary Student/Teacher Materials in Energy, the Environment, and the Economy: Mathematics in Energy, Grades 8-9.

    Science.gov (United States)

    Brown, Evelyn; And Others

    This publication is part of a series of instructional units produced by NSTA's Project for an Energy-Enriched Curriculum. The teacher's manual and the student guide for a mathematics unit in this series are presented here. This unit attempts to teach students some necessary mathematical skills needed to understand quantitative facts about energy.…

  3. Small Sample Properties of Bayesian Multivariate Autoregressive Time Series Models

    Science.gov (United States)

    Price, Larry R.

    2012-01-01

    The aim of this study was to compare the small sample (N = 1, 3, 5, 10, 15) performance of a Bayesian multivariate vector autoregressive (BVAR-SEM) time series model relative to frequentist power and parameter estimation bias. A multivariate autoregressive model was developed based on correlated autoregressive time series vectors of varying…

  4. Science initial teacher education and superdiversity: educating science teachers for a multi-religious and globalised science classroom

    Science.gov (United States)

    De Carvalho, Roussel

    2016-06-01

    Steven Vertovec (2006, 2007) has recently offered a re-interpretation of population diversity in large urban centres due to a considerable increase in immigration patterns in the UK. This complex scenario called superdiversity has been conceptualised to help illuminate significant interactions of variables such as religion, language, gender, age, nationality, labour market and population distribution on a larger scale. The interrelationships of these themes have fundamental implications in a variety of community environments, but especially within our schools. Today, London schools have over 300 languages being spoken by students, all of whom have diverse backgrounds, bringing with them a wealth of experience and, most critically, their own set of religious beliefs. At the same time, Science is a compulsory subject in England's national curriculum, where it requires teachers to deal with important scientific frameworks about the world; teaching about the origins of the universe, life on Earth, human evolution and other topics, which are often in conflict with students' religious views. In order to cope with this dynamic and thought-provoking environment, science initial teacher education (SITE)—especially those catering large urban centres—must evolve to equip science teachers with a meaningful understanding of how to handle a superdiverse science classroom, taking the discourse of inclusion beyond its formal boundaries. Thus, this original position paper addresses how the role of SITE may be re-conceptualised and re-framed in light of the immense challenges of superdiversity as well as how science teachers, as enactors of the science curriculum, must adapt to cater to these changes. This is also the first in a series of papers emerging from an empirical research project trying to capture science teacher educators' own views on religio-scientific issues and their positions on the place of these issues within science teacher education and the science classroom.

  5. Estimation of Hurst Exponent for the Financial Time Series

    Science.gov (United States)

    Kumar, J.; Manchanda, P.

    2009-07-01

    Till recently statistical methods and Fourier analysis were employed to study fluctuations in stock markets in general and Indian stock market in particular. However current trend is to apply the concepts of wavelet methodology and Hurst exponent, see for example the work of Manchanda, J. Kumar and Siddiqi, Journal of the Frankline Institute 144 (2007), 613-636 and paper of Cajueiro and B. M. Tabak. Cajueiro and Tabak, Physica A, 2003, have checked the efficiency of emerging markets by computing Hurst component over a time window of 4 years of data. Our goal in the present paper is to understand the dynamics of the Indian stock market. We look for the persistency in the stock market through Hurst exponent and fractal dimension of time series data of BSE 100 and NIFTY 50.

  6. Time series prediction by feedforward neural networks - is it difficult?

    International Nuclear Information System (INIS)

    Rosen-Zvi, Michal; Kanter, Ido; Kinzel, Wolfgang

    2003-01-01

    The difficulties that a neural network faces when trying to learn from a quasi-periodic time series are studied analytically using a teacher-student scenario where the random input is divided into two macroscopic regions with different variances, 1 and 1/γ 2 (γ >> 1). The generalization error is found to decrease as ε g ∝ exp(-α/γ 2 ), where α is the number of examples per input dimension. In contradiction to this very slow vanishing generalization error, the next output prediction is found to be almost free of mistakes. This picture is consistent with learning quasi-periodic time series produced by feedforward neural networks, which is dominated by enhanced components of the Fourier spectrum of the input. Simulation results are in good agreement with the analytical results

  7. An estimation model of population in China using time series DMSP night-time satellite imagery from 2002-2010

    Science.gov (United States)

    Zhang, Xiaoyong; Zhang, Zhijie; Chang, Yuguang; Chen, Zhengchao

    2015-12-01

    Accurate data on the spatial distribution and potential growth estimation of human population are playing pivotal role in addressing and mitigating heavy lose caused by earthquake. Traditional demographic data is limited in its spatial resolution and is extremely hard to update. With the accessibility of massive DMSP/OLS night time imagery, it is possible to model population distribution at the county level across China. In order to compare and improve the continuity and consistency of time-series DMSP night-time satellite imagery obtained by different satellites in same year or different years by the same satellite from 2002-2010, normalized method was deployed for the inter-correction among imageries. And we referred to the reference F162007 Jixi city, whose social-economic has been relatively stable. Through binomial model, with average R2 0.90, then derived the correction factor of each year. The normalization obviously improved consistency comparing to previous data, which enhanced the correspondent accuracy of model. Then conducted the model of population density between average night-time light intensity in eight-economic districts. According to the two parameters variation law of consecutive years, established the prediction model of next following years with R2of slope and constant typically 0.85 to 0.95 in different regions. To validate the model, taking the year of 2005 as example, retrieved quantitatively population distribution in per square kilometer based on the model, then compared the results to the statistical data based on census, the difference of the result is acceptable. In summary, the estimation model facilitates the quick estimation and prediction in relieving the damage to people, which is significant in decision-making.

  8. Collective pedagogical teacher culture, teacher-student ethno-racial mismatch, and teacher job satisfaction.

    Science.gov (United States)

    Stearns, Elizabeth; Banerjee, Neena; Mickelson, Roslyn; Moller, Stephanie

    2014-05-01

    Teacher job satisfaction is critical to schools' successful functioning. Using a representative sample of kindergarten teachers from the Early Childhood Longitudinal Study, we investigate the association among professional learning community and teacher collaboration, teacher ethno-racial group, teacher-student ethno-racial mismatch, and teacher job satisfaction. We find that White teachers are significantly less satisfied than African-American and Latino teachers, especially when they teach in majority non-White classrooms. However, the existence of a professional community moderates the negative influence of teacher-student ethno-racial mismatch on White teachers' job satisfaction. In effect, strong professional communities serve as a cushion to bolster teacher job satisfaction. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. A comparative analysis of spectral exponent estimation techniques for 1/f(β) processes with applications to the analysis of stride interval time series.

    Science.gov (United States)

    Schaefer, Alexander; Brach, Jennifer S; Perera, Subashan; Sejdić, Ervin

    2014-01-30

    The time evolution and complex interactions of many nonlinear systems, such as in the human body, result in fractal types of parameter outcomes that exhibit self similarity over long time scales by a power law in the frequency spectrum S(f)=1/f(β). The scaling exponent β is thus often interpreted as a "biomarker" of relative health and decline. This paper presents a thorough comparative numerical analysis of fractal characterization techniques with specific consideration given to experimentally measured gait stride interval time series. The ideal fractal signals generated in the numerical analysis are constrained under varying lengths and biases indicative of a range of physiologically conceivable fractal signals. This analysis is to complement previous investigations of fractal characteristics in healthy and pathological gait stride interval time series, with which this study is compared. The results of our analysis showed that the averaged wavelet coefficient method consistently yielded the most accurate results. Class dependent methods proved to be unsuitable for physiological time series. Detrended fluctuation analysis as most prevailing method in the literature exhibited large estimation variances. The comparative numerical analysis and experimental applications provide a thorough basis for determining an appropriate and robust method for measuring and comparing a physiologically meaningful biomarker, the spectral index β. In consideration of the constraints of application, we note the significant drawbacks of detrended fluctuation analysis and conclude that the averaged wavelet coefficient method can provide reasonable consistency and accuracy for characterizing these fractal time series. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. A comparative analysis of spectral exponent estimation techniques for 1/fβ processes with applications to the analysis of stride interval time series

    Science.gov (United States)

    Schaefer, Alexander; Brach, Jennifer S.; Perera, Subashan; Sejdić, Ervin

    2013-01-01

    Background The time evolution and complex interactions of many nonlinear systems, such as in the human body, result in fractal types of parameter outcomes that exhibit self similarity over long time scales by a power law in the frequency spectrum S(f) = 1/fβ. The scaling exponent β is thus often interpreted as a “biomarker” of relative health and decline. New Method This paper presents a thorough comparative numerical analysis of fractal characterization techniques with specific consideration given to experimentally measured gait stride interval time series. The ideal fractal signals generated in the numerical analysis are constrained under varying lengths and biases indicative of a range of physiologically conceivable fractal signals. This analysis is to complement previous investigations of fractal characteristics in healthy and pathological gait stride interval time series, with which this study is compared. Results The results of our analysis showed that the averaged wavelet coefficient method consistently yielded the most accurate results. Comparison with Existing Methods: Class dependent methods proved to be unsuitable for physiological time series. Detrended fluctuation analysis as most prevailing method in the literature exhibited large estimation variances. Conclusions The comparative numerical analysis and experimental applications provide a thorough basis for determining an appropriate and robust method for measuring and comparing a physiologically meaningful biomarker, the spectral index β. In consideration of the constraints of application, we note the significant drawbacks of detrended fluctuation analysis and conclude that the averaged wavelet coefficient method can provide reasonable consistency and accuracy for characterizing these fractal time series. PMID:24200509

  11. Multimodal Analysis of Estimated and Observed Social Competence in Preschoolers With/Without Behavior Problems

    Directory of Open Access Journals (Sweden)

    Talita Pereira Dias

    2013-05-01

    Full Text Available Social skills compete with behavior problems, and the combination of these aspects may cause differences in social competence. This study was aimed at assessing the differences and similarities in the social competence of 26 preschoolers resulting from: (1 groups which they belonged to, being one with social skills and three with behavior problems (internalizing, externalizing and mixed; (2 types of assessment, considering the estimates of mothers and teachers, as well as direct observation in a structured situation; (3 structured situations as demands for five categories of social skills. Children’s performance in each situation was assessed by judges and estimated by mothers and teachers. There was a similarity in the social competence estimated by mothers, teachers and in the performance observed. Only the teachers distinguished the groups (higher social competence in the group with social skills and lower in the internalizing and mixed groups. Assertiveness demands differentiated the groups. The methodological aspects were discussed, as well as the clinical and educational potential of the structured situations to promote social skills.

  12. SU-E-T-366: Estimation of Whole Body Dose From Cranial Irradiation From C and Perfexion Series Gamma Knife Units

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, S [Indiana University Health Methodist Hospital, Indianapolis, IN (United States); Indiana University School of Medicine, Indianapolis, IN, University Hospitals Case Medical Center, Cleaveland, OH (United States); Andersen, A; Lulu, B; Das, I [Indiana University School of Medicine, Indianapolis, IN, University Hospitals Case Medical Center, Cleaveland, OH (United States); Cheng, C

    2015-06-15

    Purpose: The Leksell Gamma Knife (GK) B & C series contains 201 Cobalt-60 sources with a helmet. The new model, Perfexion uses 192 Cobalt-60 sources without a helmet; using IRIS system for collimation and stereotactic guidance to deliver SRS to brain tumors. Relative dose to extracranial organs at risk (OARs) is measured in phantom in this study for Perfexion and C-series GK. Materials & Methods: Measurements were performed in a Rando anthropomorphic phantom on both systems using a large ion chamber (Keithley-175) for each collimator. The Keithley-175 cc ion chamber was sandwiched between phantom slices at various locations in the phantom to correspond to different extracranial OARs (thyroid, heart, kidney, ovary and testis, etc.) The dose measurement was repeated with OSL detectors for each position and collimator. Results: A large variation is observed in the normalized dose between these two systems. The dose beyond the housing falls off exponentially for Perfexion. Dose beyond the C-series GK housing falls off exponentially from 0–20cm then remains relatively constant from 20–40cm and again falls off with distance but less rapidly. The variation of extracranial dose with distance for each collimator is found to be parallel to each other for both systems. Conclusion: Whole body dose is found to vary significantly between these systems. It is important to measure the extracranial dose, especially for young patients. It is estimated that dose falls off exponentially from the GK housing and is about 1% for large collimators at 75 cm. The dose is two-orders of magnitude smaller for the 4mm collimator. However, this small dose for patient may be significant radiologically.

  13. Indirect inference with time series observed with error

    DEFF Research Database (Denmark)

    Rossi, Eduardo; Santucci de Magistris, Paolo

    estimation. We propose to solve this inconsistency by jointly estimating the nuisance and the structural parameters. Under standard assumptions, this estimator is consistent and asymptotically normal. A condition for the identification of ARMA plus noise is obtained. The proposed methodology is used......We analyze the properties of the indirect inference estimator when the observed series are contaminated by measurement error. We show that the indirect inference estimates are asymptotically biased when the nuisance parameters of the measurement error distribution are neglected in the indirect...... to estimate the parameters of continuous-time stochastic volatility models with auxiliary specifications based on realized volatility measures. Monte Carlo simulations shows the bias reduction of the indirect estimates obtained when the microstructure noise is explicitly modeled. Finally, an empirical...

  14. A Filtering of Incomplete GNSS Position Time Series with Probabilistic Principal Component Analysis

    Science.gov (United States)

    Gruszczynski, Maciej; Klos, Anna; Bogusz, Janusz

    2018-04-01

    For the first time, we introduced the probabilistic principal component analysis (pPCA) regarding the spatio-temporal filtering of Global Navigation Satellite System (GNSS) position time series to estimate and remove Common Mode Error (CME) without the interpolation of missing values. We used data from the International GNSS Service (IGS) stations which contributed to the latest International Terrestrial Reference Frame (ITRF2014). The efficiency of the proposed algorithm was tested on the simulated incomplete time series, then CME was estimated for a set of 25 stations located in Central Europe. The newly applied pPCA was compared with previously used algorithms, which showed that this method is capable of resolving the problem of proper spatio-temporal filtering of GNSS time series characterized by different observation time span. We showed, that filtering can be carried out with pPCA method when there exist two time series in the dataset having less than 100 common epoch of observations. The 1st Principal Component (PC) explained more than 36% of the total variance represented by time series residuals' (series with deterministic model removed), what compared to the other PCs variances (less than 8%) means that common signals are significant in GNSS residuals. A clear improvement in the spectral indices of the power-law noise was noticed for the Up component, which is reflected by an average shift towards white noise from - 0.98 to - 0.67 (30%). We observed a significant average reduction in the accuracy of stations' velocity estimated for filtered residuals by 35, 28 and 69% for the North, East, and Up components, respectively. CME series were also subjected to analysis in the context of environmental mass loading influences of the filtering results. Subtraction of the environmental loading models from GNSS residuals provides to reduction of the estimated CME variance by 20 and 65% for horizontal and vertical components, respectively.

  15. The Representation of Multiple Intelligences Types in the Top-Notch Series: A Textbook Evaluation

    Science.gov (United States)

    Razmjoo, Seyyed Ayatollah; Jozaghi, Zahra

    2010-01-01

    This study aims at evaluating Top-Notch series through a checklist devised by the researchers based on the elements of the Multiple Intelligences (MI) theory proposed by Gardner (1998). With the shift from teacher-centered classrooms to learner-centered one, more and more research is needed to be done in the realm of students' need analysis. One…

  16. time series modeling of daily abandoned calls in a call centre

    African Journals Online (AJOL)

    DJFLEX

    Models for evaluating and predicting the short periodic time series in daily ... Ugwuowo (2006) proposed asymmetric angular- linear multivariate regression models, ..... Using the parameter estimates in Table 3, the fitted Fourier series model is ..... For the SARIMA model with the stochastic component also being white noise, ...

  17. State energy data report 1996: Consumption estimates

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-02-01

    The State Energy Data Report (SEDR) provides annual time series estimates of State-level energy consumption by major economic sectors. The estimates are developed in the Combined State Energy Data System (CSEDS), which is maintained and operated by the Energy Information Administration (EIA). The goal in maintaining CSEDS is to create historical time series of energy consumption by State that are defined as consistently as possible over time and across sectors. CSEDS exists for two principal reasons: (1) to provide State energy consumption estimates to Members of Congress, Federal and State agencies, and the general public and (2) to provide the historical series necessary for EIA`s energy models. To the degree possible, energy consumption has been assigned to five sectors: residential, commercial, industrial, transportation, and electric utility sectors. Fuels covered are coal, natural gas, petroleum, nuclear electric power, hydroelectric power, biomass, and other, defined as electric power generated from geothermal, wind, photovoltaic, and solar thermal energy. 322 tabs.

  18. State energy data report 1996: Consumption estimates

    International Nuclear Information System (INIS)

    1999-02-01

    The State Energy Data Report (SEDR) provides annual time series estimates of State-level energy consumption by major economic sectors. The estimates are developed in the Combined State Energy Data System (CSEDS), which is maintained and operated by the Energy Information Administration (EIA). The goal in maintaining CSEDS is to create historical time series of energy consumption by State that are defined as consistently as possible over time and across sectors. CSEDS exists for two principal reasons: (1) to provide State energy consumption estimates to Members of Congress, Federal and State agencies, and the general public and (2) to provide the historical series necessary for EIA's energy models. To the degree possible, energy consumption has been assigned to five sectors: residential, commercial, industrial, transportation, and electric utility sectors. Fuels covered are coal, natural gas, petroleum, nuclear electric power, hydroelectric power, biomass, and other, defined as electric power generated from geothermal, wind, photovoltaic, and solar thermal energy. 322 tabs

  19. Decreasing pH trend estimated from 25-yr time series of carbonate parameters in the western North Pacific

    Energy Technology Data Exchange (ETDEWEB)

    Midorikawa, Takashi; Ishii, Masao; Sasano, Daisuke; Kosugi, Naohiro (Geochemical Research Dept., Meteorological Research Institute Tsukuba (Japan)), e-mail: midorika@mri-jma.go.jp; Saito, Shu (Geochemical Research Dept., Meteorological Research Institute, Tsukuba (Japan); Institute of Observational Research for Global Change (IORGC), Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Yokosuka (Japan)); Motoi, Tatsuo (Oceanographic Research Dept., Meteorological Research Institute, Tsukuba (Japan)); Kamiya, Hitomi; Nakadate, Akira; Nemoto, Kazuhiro (Global Environment and Marine Dept., Japan Meteorological Agency, Tokyo (Japan)); Inoue, Hisayuki Y. (Graduate School of Environmental Earth Science, Hokkaido Univ., Sapporo (Japan))

    2010-11-15

    We estimated long-term trends of ocean acidification in surface waters in latitudinal zones from 3 deg N to 33 deg N along the repeat hydrographic line at 137 deg E in the western North Pacific Ocean. Estimates were based on the observational records of oceanic CO{sub 2} partial pressure and related surface properties over the last two decades. The computed pH time series both for 25 yr in winter (late January to early February) and for 21 yr in summer (June-July) exhibited significant decreasing trends in the extensive subtropical to equatorial zones, with interannual variations that were larger in summer. The calculated rates of pH decrease ranged from 0.0015 to 0.0021 yr-1 (average, 0.0018 +- 0.0002 yr-1) in winter and from 0.0008 to 0.0019 yr-1 (average, 0.0013 +- 0.0005 yr-1 ) in summer. The thermodynamic effects of rising sea surface temperature (SST) accounted for up to 44% (average, 15%) of the trend of pH decrease in the subtropical region in winter, whereas a trend of decreasing SST slowed the pH decrease in the northern subtropical region (around 25 deg N) in summer. We used the results from recent trends to evaluate future possible thermodynamic changes in the upper ocean carbonate system

  20. Estimation of time averages from irregularly spaced observations - With application to coastal zone color scanner estimates of chlorophyll concentration

    Science.gov (United States)

    Chelton, Dudley B.; Schlax, Michael G.

    1991-01-01

    The sampling error of an arbitrary linear estimate of a time-averaged quantity constructed from a time series of irregularly spaced observations at a fixed located is quantified through a formalism. The method is applied to satellite observations of chlorophyll from the coastal zone color scanner. The two specific linear estimates under consideration are the composite average formed from the simple average of all observations within the averaging period and the optimal estimate formed by minimizing the mean squared error of the temporal average based on all the observations in the time series. The resulting suboptimal estimates are shown to be more accurate than composite averages. Suboptimal estimates are also found to be nearly as accurate as optimal estimates using the correct signal and measurement error variances and correlation functions for realistic ranges of these parameters, which makes it a viable practical alternative to the composite average method generally employed at present.

  1. Teacher quality moderates the genetic effects on early reading.

    Science.gov (United States)

    Taylor, J; Roehrig, A D; Soden Hensler, B; Connor, C M; Schatschneider, C

    2010-04-23

    Children's reading achievement is influenced by genetics as well as by family and school environments. The importance of teacher quality as a specific school environmental influence on reading achievement is unknown. We studied first- and second-grade students in Florida from schools representing diverse environments. Comparison of monozygotic and dizygotic twins, differentiating genetic similarities of 100% and 50%, provided an estimate of genetic variance in reading achievement. Teacher quality was measured by how much reading gain the non-twin classmates achieved. The magnitude of genetic variance associated with twins' oral reading fluency increased as the quality of their teacher increased. In circumstances where the teachers are all excellent, the variability in student reading achievement may appear to be largely due to genetics. However, poor teaching impedes the ability of children to reach their potential.

  2. English Language Teacher Education: Rewriting S-1 National Curriculum

    Directory of Open Access Journals (Sweden)

    M. Soenardi Djiwandono

    1999-01-01

    Full Text Available As part of an overall attempt to improve secondary school teacher education, a program has been launched to review and develop the national curriculum (KURNAS of English language teacher education in Indonesia as a means to improve the quality of teachers of English. The new curriculum is at the same time intended to be a revision of the 1995 national curriculum supposedly in use now. For the purpose a team of three members was appointed by the Secondary School Teacher Development Project (nationally known as Proyek PGSM, comprising English teaching professionalls from Universitas Negeri Malang, GAJAHMADA UNIVERSITY, and a senior high school teacher of English. Following a study of the existing documents related to ELT in Indonesia, an initial draft was written and gradually developed following a series of discussions and exchanges of ideas with teachers and profesionalls in the field of ELT. By the 3 rd year of the appointment of the team, the draft for the new KURNAS comprising Books I, II, and III, has been completed and ready for a try-out. The try-out was intended to put into practise the Intensive Course (IC Program as one of the most important components of the new KURNAS for the development of fluency in English as an essential basis for the preparation of competent high school teachers of English. This article describes the background and the underlying principles of the curriculum revision, along with the classification and identification of courses, descriptions of courses their and syllabus outlines.

  3. Students' and teachers' cognitions about good teachers.

    Science.gov (United States)

    Beishuizen, J J; Hof, E; van Putten, C M; Bouwmeester, S; Asscher, J J

    2001-06-01

    Good teachers have been studied ever since Plato described how Socrates taught by asking questions of his audience. Recent findings shed light on two characteristics of good teachers: their personality and their ability. However, more attention has been paid to teachers' practices and opinions than to students' views. The study reported here attempted to deepen our understanding of what students think about good teachers. Students of four age groups (7, 10, 13, and 16 years of age) and teachers from primary and secondary schools were asked to write an essay on the good teacher. The correspondence between conceptual items in the essays was investigated by determining the extent to which they were used in the same essays to describe good teachers. Correspondence analysis revealed two dimensions. The first dimension reflected the preference of students and teachers for describing the good teacher in terms of either personality or ability characteristics. The second dimension was interpreted as an orientation in the essays towards either attachment to, detachment from or commitment to school and teachers. Students and teachers were compared to establish the amount of (dis)agreement about what makes a good teacher. Primary school students described good teachers primarily as competent instructors, focusing on transfer of knowledge and skills, whereas secondary school students emphasised relational aspects of good teachers. Teachers, however, considered good teachers in the first place a matter of establishing personal relationships with their students. Consequently, primary school students and teachers disagreed about the characteristics of good teachers. In secondary education, disagreements between teachers and students were relatively small. The research method of collecting free essays and utilising correspondence analysis to represent conceptual items and groups of participants seems promising as long as a theoretical framework is available to interpret the

  4. Teacher Pay and Teacher Aptitude

    Science.gov (United States)

    Leigh, Andrew

    2012-01-01

    Can changes in teacher pay encourage more able individuals to enter the teaching profession? So far, studies of the impact of pay on the aptitude distribution of teachers have provided mixed evidence on the extent to which altering teacher salaries represents a feasible solution to the teacher quality problem. One possible reason is that these…

  5. ACER Mathematics Profile Series: Number Test. (Test Booklet, Answer and Record Sheet, Score Key, and Teachers Handbook).

    Science.gov (United States)

    Cornish, Greg; Wines, Robin

    The Number Test of the ACER Mathematics Profile Series, contains 30 items, for each of three suggested grade levels: 7-8, 8-9, and 9-10. Raw scores on all tests in the ACER Mathematics Profile Series (Number, Operations, Space and Measurement) are converted to a common scale called MAPS, a major feature of the Series. Based on the Rasch Model,…

  6. 75 FR 15321 - Airworthiness Directives; Rolls-Royce plc RB211-Trent 800 Series Turbofan Engines

    Science.gov (United States)

    2010-03-29

    ... Directives; Rolls-Royce plc RB211-Trent 800 Series Turbofan Engines AGENCY: Federal Aviation Administration... Based on the service information, we estimate that this AD will affect about 138 RB211 Trent 800 series... will cost about $2,000 per engine. Based on these figures, we estimate the cost of the AD on U.S...

  7. Conditional mode regression: Application to functional time series prediction

    OpenAIRE

    Dabo-Niang, Sophie; Laksaci, Ali

    2008-01-01

    We consider $\\alpha$-mixing observations and deal with the estimation of the conditional mode of a scalar response variable $Y$ given a random variable $X$ taking values in a semi-metric space. We provide a convergence rate in $L^p$ norm of the estimator. A useful and typical application to functional times series prediction is given.

  8. Understanding Aggregation and Estimating Seasonal Abundance of Chrysaora quinquecirrha Medusae from a Fixed-station Time Series in the Choptank River, Chesapeake Bay

    Science.gov (United States)

    Tay, J.; Hood, R. R.

    2016-02-01

    Although jellyfish exert strong control over marine plankton dynamics (Richardson et al. 2009, Robison et al. 2014) and negatively impact human commercial and recreational activities (Purcell et al. 2007, Purcell 2012), jellyfish biomass is not well quantified due primarily to sampling difficulties with plankton nets or fisheries trawls (Haddock 2004). As a result, some of the longest records of jellyfish are visual shore-based surveys, such as the fixed-station time series of Chrysaora quinquecirrha that began in 1960 in the Patuxent River in Chesapeake Bay, USA (Cargo and King 1990). Time series counts from fixed-station surveys capture two signals: 1) demographic change at timescales on the order of reproductive processes and 2) spatial patchiness at shorter timescales as different parcels of water move in and out of the survey area by tidal and estuarine advection and turbulent mixing (Lee and McAlice 1979). In this study, our goal was to separate these two signals using a 4-year time series of C. quinquecirrha medusa counts from a fixed-station in the Choptank River, Chesapeake Bay. Idealized modeling of tidal and estuarine advection was used to conceptualize the sampling scheme. Change point and time series analysis was used to detect demographic changes. Indices of aggregation (Negative Binomial coefficient, Taylor's Power Law coefficient, and Morisita's Index) were calculated to describe the spatial patchiness of the medusae. Abundance estimates revealed a bloom cycle that differed in duration and magnitude for each of the study years. Indices of aggregation indicated that medusae were aggregated and that patches grew in the number of individuals, and likely in size, as abundance increased. Further inference from the conceptual modeling suggested that medusae patch structure was generally homogenous over the tidal extent. This study highlights the benefits of using fixed-station shore-based surveys for understanding the biology and ecology of jellyfish.

  9. How Do Value-Added Indicators Compare to Other Measures of Teacher Effectiveness? What We Know Series: Value-Added Methods and Applications. Knowledge Brief 5

    Science.gov (United States)

    Harris, Douglas N.

    2012-01-01

    In the recent drive to revamp teacher evaluation and accountability, measures of a teacher's value added have played the starring role. But the star of the show is not always the best actor, nor can the star succeed without a strong supporting cast. In assessing teacher performance, observations of classroom practice, portfolios of teachers' work,…

  10. Detection of increased series losses in PV arrays using Fuzzy Inference Systems

    DEFF Research Database (Denmark)

    Spataru, Sergiu; Sera, Dezso; Kerekes, Tamas

    2012-01-01

    There are well-defined methods to measure the (increased) series resistance of PV panels in controlled laboratory conditions. However, the presence of various irradiance levels and partial shadows, in case of an outdoor installation, may affect the series resistance estimation. This paper focuses...

  11. A new multidimensional measure of African adolescents' perceptions of teachers' behaviors.

    Science.gov (United States)

    Mboya, M M

    1994-04-01

    The Perceived Teacher Behavior Inventory was designed to measure three dimensions of students' perceptions of the behaviors of their teachers. This research was conducted to assess the statistical validity and reliability of the instrument administered to 770 students attending two coeducational high schools in Cape Town, South Africa. Factor analysis clearly identified three subscales indicating that the instrument distinguished the students' perceptions of their teachers' behaviors in three areas. Estimates of internal consistency of the subscales were assessed using the squared multiple correlation as the index of reliability.

  12. Estimating monotonic rates from biological data using local linear regression.

    Science.gov (United States)

    Olito, Colin; White, Craig R; Marshall, Dustin J; Barneche, Diego R

    2017-03-01

    Accessing many fundamental questions in biology begins with empirical estimation of simple monotonic rates of underlying biological processes. Across a variety of disciplines, ranging from physiology to biogeochemistry, these rates are routinely estimated from non-linear and noisy time series data using linear regression and ad hoc manual truncation of non-linearities. Here, we introduce the R package LoLinR, a flexible toolkit to implement local linear regression techniques to objectively and reproducibly estimate monotonic biological rates from non-linear time series data, and demonstrate possible applications using metabolic rate data. LoLinR provides methods to easily and reliably estimate monotonic rates from time series data in a way that is statistically robust, facilitates reproducible research and is applicable to a wide variety of research disciplines in the biological sciences. © 2017. Published by The Company of Biologists Ltd.

  13. What does it mean to be an exemplary science teacher?

    Science.gov (United States)

    Tobin, Kenneth; Fraser, Barry J.

    In order to provide a refreshing alternative to the majority of research reports, which malign science education and highlight its major problems and shortcomings, a series of case studies of exemplary practice was initiated to provide a focus on the successful and positive facets of schooling. The major data-collection approach was qualitative and involved 13 researchers in hundreds of hours of intensive classroom observation involving 20 exemplary teachers and a comparison group of nonexemplary teachers. A distinctive feature of the methodology was that the qualitative information was complemented by quantitative information obtained from the administration of questionnaires assessing student perceptions of classroom psychosocial environment. The major trends were that exemplary science teachers (1) used management strategies that facilitated sustained student engagement, (2) used strategies designed to increase student understanding of science, (3) utilized strategies that encouraged students to participate in learning activities, and (4) maintained a favorable classroom learning environment.

  14. Improving cluster-based missing value estimation of DNA microarray data.

    Science.gov (United States)

    Brás, Lígia P; Menezes, José C

    2007-06-01

    We present a modification of the weighted K-nearest neighbours imputation method (KNNimpute) for missing values (MVs) estimation in microarray data based on the reuse of estimated data. The method was called iterative KNN imputation (IKNNimpute) as the estimation is performed iteratively using the recently estimated values. The estimation efficiency of IKNNimpute was assessed under different conditions (data type, fraction and structure of missing data) by the normalized root mean squared error (NRMSE) and the correlation coefficients between estimated and true values, and compared with that of other cluster-based estimation methods (KNNimpute and sequential KNN). We further investigated the influence of imputation on the detection of differentially expressed genes using SAM by examining the differentially expressed genes that are lost after MV estimation. The performance measures give consistent results, indicating that the iterative procedure of IKNNimpute can enhance the prediction ability of cluster-based methods in the presence of high missing rates, in non-time series experiments and in data sets comprising both time series and non-time series data, because the information of the genes having MVs is used more efficiently and the iterative procedure allows refining the MV estimates. More importantly, IKNN has a smaller detrimental effect on the detection of differentially expressed genes.

  15. A professional experience learning community for secondary mathematics: developing pre-service teachers' reflective practice

    Science.gov (United States)

    Cavanagh, Michael; McMaster, Heather

    2015-12-01

    This paper reports on the reflective practice of a group of nine secondary mathematics pre-service teachers. The pre-service teachers participated in a year-long, school-based professional experience program which focussed on observing, co-teaching and reflecting on a series of problem-solving lessons in two junior secondary school mathematics classrooms. The study used a mixed methods approach to consider the impact of shared pedagogical conversations on pre-service teachers' written reflections. It also examined whether there were differences in the focus of reflections depending on whether the lesson was taught by an experienced mathematics teacher, or taught by a pair of their peers, or co-taught by themselves with a peer. Results suggest that after participants have observed lessons taught by an experienced teacher and reflected collaboratively on those lessons, they continue to reflect on lessons taught by their peers and on their own lessons when co-teaching, rather than just describe or evaluate them. However, their written reflections across all contexts continued to focus primarily on teacher actions and classroom management rather than on student learning.

  16. Teachers Learning to Teach Science by Doing Science at the University of Arizona

    Science.gov (United States)

    Mangin, K. L.; Thompson, R. M.; Wilch, M.

    2006-12-01

    Many departments across the College of Science at the University of Arizona provide the opportunity for teachers to do original scientific research. These programs either provide skills and curriculum that can be translated into the classroom or include direct participation by K-12 students with their teachers. This paper introduces three of the many unique programs that UA offers for teacher professional development. The College of Science offers a teacher professional development course to accompany a public lecture series that runs each semester on a different topic of current social and scientific interest. During the Spring 2006 semester, the series subject was evolution, with attendance at each lecture running in excess of 600. This fall, the topic is climate change. In addition to attending lectures and participating in group discussions with the speakers, the teachers conduct research into regional climate change using the Western Regional Climate Center's publicly available, web-hosted climate data. The teachers brainstorm about possible influences on the data other than anthropogenic alteration of atmospheric composition, and control for these influences in their experimental design as best they can. Such influences might include urbanization, instrumental change, and natural variability. The College of Science is developing collaborations with community partners, including a local high school science magnet and a high school in the Galapagos Islands. Among several programs created in partnership with Tucson High School, Science and Nature in Tandem for Youth (SANITY) brings science teachers and students to the Southwest Research Station to conduct ecological research of their own design including the investigation of the effects of drought and other physical factors on the biosphere. The Southwest Research Station is located in the Chiricahua Mountains, one of the so-called "sky islands" and a crucial cradle of biodiversity vulnerable to the effects of

  17. [Impact of medical TV series on surgical hospital patient's perception of reality].

    Science.gov (United States)

    Witzel, Kai; Weitzendorfer, Michael; Schredl, Philip; Koch, Horst J; Kaminski, Cornelia

    2018-03-02

    Medical TV series are very popular. Media research emphasizes that watching TV has an influence on patient's expectations and estimations concerning upcoming surgery. We analyzed these associations in our own patients. We suspected that reality as presented in the media and the actual reality of hospitals are not always conceived as two different worlds. Over a 15-month period a standardized questionnaire was used to interview 162 in-house patients who had been admitted for an elective standard operation. They were interviewed 1-2 days prior to surgery and shortly before discharge from hospital. The questions aimed at their social situation and their TV viewing habits with special consideration of medical TV series. The knowledge of medical TV series is highly associated with a realistic assessment of these programs (p TV series have a significant influence on surgical in-house patients. Patients with knowledge of many medical TV series believe that the medical setting in these shows is realistic. This can result in false estimations concerning real surgery.

  18. Elinor M. Brent-Dyer's Chalet School Series: Literature as an Historical Source

    Science.gov (United States)

    Lidbury, Clare

    2013-01-01

    This article examines whether Elinor M. Brent-Dyer's Chalet School books--a series of girls' school stories spanning the late 1920s to the early 1970s--can be regarded as historical sources for the study of physical education and dance in girls' boarding schools during this period. An overview of her experience as teacher and…

  19. Parameter estimation in stochastic rainfall-runoff models

    DEFF Research Database (Denmark)

    Jonsdottir, Harpa; Madsen, Henrik; Palsson, Olafur Petur

    2006-01-01

    A parameter estimation method for stochastic rainfall-runoff models is presented. The model considered in the paper is a conceptual stochastic model, formulated in continuous-discrete state space form. The model is small and a fully automatic optimization is, therefore, possible for estimating all...... the parameter values are optimal for simulation or prediction. The data originates from Iceland and the model is designed for Icelandic conditions, including a snow routine for mountainous areas. The model demands only two input data series, precipitation and temperature and one output data series...

  20. Use of a C-SITS Approach to Estimating the Impact of the Receipt of a Teacher Recruitment Incentive Grant on an IHE's Production of Certified STEM Teachers--Problems and Solutions

    Science.gov (United States)

    Bobronnikov, Ellen; Price, Cris

    2013-01-01

    Improving the quality of teacher preparation is an important national issue, because the quality of teaching plays such a large role in students' learning. One key indicator of students' academic success is the competence and capability of their teachers. However, the availability of well-prepared and effective teachers varies widely across the…

  1. Principal-Teacher Interactions and Teacher Leadership Development: Beginning Teachers' Perspectives

    Science.gov (United States)

    Szeto, Elson; Cheng, Annie Yan-Ni

    2018-01-01

    Teacher leadership lies at the heart of school improvement. Leadership development among beginning teachers, however, is often neglected. This paper examines the role of principal-teacher interactions in the leadership development of a group of beginning teachers. Using a case study design, interviews were conducted and documentary evidence was…

  2. Corporeality and playfulness in initial series of elementary school: beliefs, doubts and possibilities

    Directory of Open Access Journals (Sweden)

    Lucia Helena Pena Pereira

    2015-11-01

    Full Text Available This study aimed to understand the difficulties found in that corporeality and playfulness may be more experienced in the classroom from the initial series of elementary school. The field research was a qualitative had the collaboration of four teachers from public schools of Minas Gerais. It was found that corporeality and playfulness are important aspects of the reality of the educator in this step and is necessary a new understanding of these aspects. The play activities are presented as a valuable opportunity to work the corporeality, the creativity and the expressiveness both the student as the educator. Also appear as a contribution to the strengthening of teacher-student bonding and development dimensions of affective, cognitive and motor skills of the child.

  3. Ideas, Creencias, Actitudes. Primer Modulo de una Serie para Maestros de Escuela Elemental (Ideas, Beliefs, Attitudes. First Module of a Series for Elementary Teachers).

    Science.gov (United States)

    Molina, Carmen Eneida, Ed.; And Others

    This guide for teachers, in English and Spanish, examines the role of stereotypes within the context of contemporary beliefs, ideas, and attitudes. A pre-test and post-test are included to measure the user's awareness of stereotypes. Object lessons cover the following topics: (1) definition of stereotypes; (2) racial and ethnic stereotypes; (3)…

  4. TEACHER PERCEPTIONS OF SUPERVISOR-TEACHER INTERACTION.

    Science.gov (United States)

    AMIDON, EDMUND; BLUMBERG, ARTHUR

    TEACHER PERCEPTIONS OF SUPERVISOR-TEACHER INTERACTION WERE ANALYZED TO SUPPORT THE HYPOTHESIS THAT FOUR GROUPS, REPRESENTING DIFFERENT PERCEPTIONS OF SUPERVISORY BEHAVIOR, WOULD DIFFER WITH RESPECT TO TEACHER EVALUATIONS OF CONFERENCE PRODUCTIVITY, CONFERENCE LEARNING, AND THE COMMUNICATIVE ATMOSPHERE. THE 166 GRADUATE INSERVICE TEACHERS AT TEMPLE…

  5. The partial duration series method in regional index-flood modeling

    DEFF Research Database (Denmark)

    Madsen, Henrik; Rosbjerg, Dan

    1997-01-01

    A regional index-flood method based on the partial duration series model is introduced. The model comprises the assumptions of a Poisson-distributed number of threshold exceedances and generalized Pareto (GP) distributed peak magnitudes. The regional T-year event estimator is based on a regional...... estimator is superior to the at-site estimator even in extremely heterogenous regions, the performance of the regional estimator being relatively better in regions with a negative shape parameter. When the record length increases, the relative performance of the regional estimator decreases, but it is still...

  6. Long Memory Models to Generate Synthetic Hydrological Series

    Directory of Open Access Journals (Sweden)

    Guilherme Armando de Almeida Pereira

    2014-01-01

    Full Text Available In Brazil, much of the energy production comes from hydroelectric plants whose planning is not trivial due to the strong dependence on rainfall regimes. This planning is accomplished through optimization models that use inputs such as synthetic hydrologic series generated from the statistical model PAR(p (periodic autoregressive. Recently, Brazil began the search for alternative models able to capture the effects that the traditional model PAR(p does not incorporate, such as long memory effects. Long memory in a time series can be defined as a significant dependence between lags separated by a long period of time. Thus, this research develops a study of the effects of long dependence in the series of streamflow natural energy in the South subsystem, in order to estimate a long memory model capable of generating synthetic hydrologic series.

  7. Contextualization processes and the initial education of physics teachers

    Directory of Open Access Journals (Sweden)

    Cristina Cândida de Macedo

    2014-03-01

    Full Text Available Contextualization of school contents has been seen as a possibility of facilitating students’ learning, since it makes the educative process more significant to them. However, there is no agreement as to the meaning and the forms of applying such processes. Particularly in the area of Science teaching, the creation of thematic projects has been seen as a way of contextualizing school contents. It is noteworthy that the experience with the education of Physics teachers shows that the creation and execution of such projects brings many difficulties to teachers, the main obstacle being the understanding of what contextualized educative processes are. Having this in mind, a project has been elaborated with the objective of analyzing the comprehension Physics teachers that are going through teacher education courses have of the processes of contextualization. The data for this investigation has been obtained from students who attended a course of the Physics Teacher Education module at the Federal University of Itajubá. It is significant to mention that in this course students are asked to create three versions of a thematic project. In order to analyze the data, the procedure of Thematic Content and Category Analysis was adopted. This research shows that Physics teachers to be incorporate the discourses of the educative ideas throughout the course. However, there is a series of obstacles they face as they attempt to understand and carry out contextualized educative processes. Those difficulties are connected to their experience with this kind of educative process throughout the years they spend at school and in the teacher education course. We conclude thus that it is essential that contextualized educative activities be part of the reality of teacher education programs.

  8. Creating Teachers' Perceptual, Behavioral, and Attitudinal Change Using Professional Development Workshops

    Science.gov (United States)

    Shriner, Michael; Schlee, Bethanne; Hamil, Melissa; Libler, Rebecca

    2009-01-01

    As part of an on-going project designed to impact teacher quality at the pre-service, induction, and professional development levels, this paper summarizes the parametric results of a series of four different workshops conducted in the summer of 2007. In an effort to glean a better understanding of their knowledge, attitudinal, perceptual, and…

  9. Comparison of voice-use profiles between elementary classroom and music teachers.

    Science.gov (United States)

    Morrow, Sharon L; Connor, Nadine P

    2011-05-01

    Among teachers, music teachers are roughly four times more likely than classroom teachers to develop voice-related problems. Although it has been established that music teachers use their voices at high intensities and durations in the course of their workday, voice-use profiles concerning the amount and intensity of vocal use and vocal load have neither been quantified nor has vocal load for music teachers been compared with classroom teachers using these same voice-use parameters. In this study, total phonation time, fundamental frequency (F₀), and vocal intensity (dB SPL [sound pressure level]) were measured or estimated directly using a KayPENTAX Ambulatory Phonation Monitor (KayPENTAX, Lincoln Park, NJ). Vocal load was calculated as cycle and distance dose, as defined by Švec et al (2003), which integrates total phonation time, F₀, and vocal intensity. Twelve participants (n = 7 elementary music teachers and n = 5 elementary classroom teachers) were monitored during five full teaching days of one workweek to determine average vocal load for these two groups of teachers. Statistically significant differences in all measures were found between the two groups (P vocal loads for music teachers are substantially higher than those experienced by classroom teachers (P vocal load may have immediate clinical and educational benefits in vocal health in music teachers. Copyright © 2011 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

  10. Estimating the Persistence and the Autocorrelation Function of a Time Series that is Measured with Error

    DEFF Research Database (Denmark)

    Hansen, Peter Reinhard; Lunde, Asger

    2014-01-01

    An economic time series can often be viewed as a noisy proxy for an underlying economic variable. Measurement errors will influence the dynamic properties of the observed process and may conceal the persistence of the underlying time series. In this paper we develop instrumental variable (IV...

  11. The Impact of the Hotel Room Tax: An Interrupted Time Series Approach

    OpenAIRE

    Bonham, Carl; Fujii, Edwin; Im, Eric; Mak, James

    1992-01-01

    Employs interrupted time series analysis to estimate ex post the impact of a hotel room tax on real net hotel revenues by analyzing that time series before and after the imposition of the tax. Finds that the tax had a negligible effect on real hotel revenues.

  12. Who's the Goat. A UNIPAC for the Teacher, School Year 1968-1969.

    Science.gov (United States)

    Evanston School District 65, IL.

    Developed during a 1968 summer institute for assisting educators of Evanston, Illinois School District 65 to develop some common understandings about crucial integration issues, this set of instructional materials on "Who's the Goat" forms one of a series of teacher "Unipacs." The specific purpose of this Unipac is to help…

  13. On-line analysis of reactor noise using time-series analysis

    International Nuclear Information System (INIS)

    McGevna, V.G.

    1981-10-01

    A method to allow use of time series analysis for on-line noise analysis has been developed. On-line analysis of noise in nuclear power reactors has been limited primarily to spectral analysis and related frequency domain techniques. Time series analysis has many distinct advantages over spectral analysis in the automated processing of reactor noise. However, fitting an autoregressive-moving average (ARMA) model to time series data involves non-linear least squares estimation. Unless a high speed, general purpose computer is available, the calculations become too time consuming for on-line applications. To eliminate this problem, a special purpose algorithm was developed for fitting ARMA models. While it is based on a combination of steepest descent and Taylor series linearization, properties of the ARMA model are used so that the auto- and cross-correlation functions can be used to eliminate the need for estimating derivatives. The number of calculations, per iteration varies lineegardless of the mee 0.2% yield strength displayed anisotropy, with axial and circumferential values being greater than radial. For CF8-CPF8 and CF8M-CPF8M castings to meet current ASME Code S acid fuel cells

  14. Job stressors and job stress among teachers engaged in nursing activity.

    Science.gov (United States)

    Muto, Shigeki; Muto, Takashi; Seo, Akihiko; Yoshida, Tsutomu; Taoda, Kazushi; Watanabe, Misuzu

    2007-01-01

    Teachers and staff members engaged in nursing activity experience more stress than other workers. However, it is unknown whether teachers engaged in nursing activity in schools for handicapped children experience even greater stress. This study evaluated job stressors and job stress among such teachers using a cross-sectional study design. The subjects were all 1,461 teachers from all 19 prefectural schools for handicapped children in Shizuoka Prefecture, Japan. We used a brief job stress questionnaire for the survey and 831 teachers completed the questionnaire. Job stressors among teachers engaged in nursing activity were compared with those among teachers not engaged in nursing activity. Job stress among such teachers was estimated by the score for total health risk, and was compared with the score in the Japanese general population. Male and female teachers engaged in nursing activity had a significantly higher level of job stressors for physical work load and job control compared with those not engaged in nursing activity. The scores for total health risk among male and female teachers engaged in nursing activity were 102 points and 98 points, respectively. These scores were not markedly above 100 points which is the mean score in the Japanese general population.

  15. High school teacher enhancement in the sciences

    Energy Technology Data Exchange (ETDEWEB)

    Mohamed, A. [Jackson State Univ., MS (United States). School of Science and Technology; Shepard, R.L. [Science and Engineering Alliance, Inc., Washington, DC (United States)

    1997-03-01

    As part of an effort to improve the teaching of science in a four-State region (Alabama, Mississippi, Louisiana, and Texas), the Science and Engineering Alliance (SEA) initiated a series of teacher enhancement workshops in science. The workshops focus on teaching problem solving through experience gained in laboratory, field work, classroom discussions and interactions/debates, critical analysis of the literature, obtaining a greater appreciation of the application of mathematics in science, and interactions with experts in various fields of science.

  16. Visiting digital fluency for pre-service teachers in Turkey

    OpenAIRE

    Kadir Demir; Betül Aydın; Nazife Şen Ersoy; Aydın Kelek; İsmail Tatar; Abdullah Kuzu; Hatice Ferhan Odabaşı

    2015-01-01

    Digital literacy is to know how to use digital tools, however digital fluency is a new concept. Beyond the digital literacy, digital fluency requires skills to know when to use the technology and even why to use the technology. The technology advances rapidly; as a result, education and instruction are getting digitalized. So it could be estimated that; pre-service teachers who are future teachers, should have digital skills. This is the main point of this study which aims to visit pre-ser...

  17. Problems of discipline in primary and secondary school: Teachers' opinions

    Directory of Open Access Journals (Sweden)

    Savović Branka B.

    2002-01-01

    Full Text Available Investigations carried out in late 2001 in primary and secondary schools of Belgrade, Novi Sad and Niš comprised students, teachers and associates. The aim of investigations was to get insight into the state-of-the-arts problems and needs of our primary and secondary schools. The paper is a part of investigations, related to the results obtained for students' opinions of their interrelations with teachers as well as opinions of teachers themselves. The sample comprised 727 students of 4th grade of secondary vocational and high schools, 562 students of 8th grade of primary schools 168 secondary school and 107 primary school teachers. We investigated their interrelationships and within this framework the level of potential or current aggressive behavior. The majority of teachers (51% estimated student-teacher relationships mediocre - neither good nor bad. The most frequent problem in students' behavior is, according to the teachers instruction disturbance. One-quarter of teachers find that students offend them, ridicule them, or mock at them in front of others, and 5 per cent complain of physical injury intimidation on the part of students. When a problem comes up, 18 per cent of teachers talk with a student, and nearly 10 per cent of teachers give lower grades in their subject, so as to punish a student for undisciplined behaviors. In teachers' opinion, society, school the least, is to be blamed for the situation.

  18. Robust Control Charts for Time Series Data

    NARCIS (Netherlands)

    Croux, C.; Gelper, S.; Mahieu, K.

    2010-01-01

    This article presents a control chart for time series data, based on the one-step- ahead forecast errors of the Holt-Winters forecasting method. We use robust techniques to prevent that outliers affect the estimation of the control limits of the chart. Moreover, robustness is important to maintain

  19. I-LLINI Partnerships for 21st Century Teachers

    Science.gov (United States)

    Read, K.; Wong, K.; Charlevoix, D. J.; Tomkin, J.; Hug, B.; Williams, M.; Pianfetti, E.

    2008-12-01

    I-LLINI Partnerships is two-year State funded program to initiate enhance communication between the faculty at University of Illinois and K-12 teachers in the surrounding communities. The program focuses on math and science with a particular emphasis on the use of technology to teaching math and science to middle-school aged children. The Partnership provides participating teachers with a suite of technology including a computer, digital camera, and software, as well as a small stipend. University partners include representatives from the Departments of Mathematics as well as the Department of Atmospheric Sciences and the Department of Geology. The Atmospheric Sciences and Geology faculty have partnered to provide content using an Earth Systems Science approach to presenting content to the teachers. Additionally, teachers provide feedback to university faculty with relation to how they might better prepare future science teachers. Teacher participants are required to attend a series of workshops during the academic year as well as a summer workshop. The first workshop was held June 2008 on the University of Illinois campus. Our poster will highlight the first workshop providing a discussion and photographs of the activities, an analysis of the benefits and challenges - both to the university representatives as well as the teachers ­ and a summary of future changes planned for the 2009 summer workshop. During the second morning of the workshop, the science teachers participated in an EcoBlitz via a field trip to a collect data from a stream near campus. During the EcoBlitz, math teachers attended tutorial sessions on campus on statistical analysis software. The EcoBliz teachers were provided with instruments and equipment necessary to collect data on the weather conditions and water quality of the stream. Instruments included a temperature probe, turbidity sensor, dissolved oxygen sensor and a hand held weather instrument. Data was recorded with Vernier Lab

  20. Tracking variable sedimentation rates in orbitally forced paleoclimate proxy series

    Science.gov (United States)

    Li, M.; Kump, L. R.; Hinnov, L.

    2017-12-01

    This study addresses two fundamental issues in cyclostratigraphy: quantitative testing of orbital forcing in cyclic sedimentary sequences and tracking variable sedimentation rates. The methodology proposed here addresses these issues as an inverse problem, and estimates the product-moment correlation coefficient between the frequency spectra of orbital solutions and paleoclimate proxy series over a range of "test" sedimentation rates. It is inspired by the ASM method (1). The number of orbital parameters involved in the estimation is also considered. The method relies on the hypothesis that orbital forcing had a significant impact on the paleoclimate proxy variations, and thus is also tested. The null hypothesis of no astronomical forcing is evaluated using the Beta distribution, for which the shape parameters are estimated using a Monte Carlo simulation approach. We introduce a metric to estimate the most likely sedimentation rate using the product-moment correlation coefficient, H0 significance level, and the number of contributing orbital parameters, i.e., the CHO value. The CHO metric is applied with a sliding window to track variable sedimentation rates along the paleoclimate proxy series. Two forward models with uniform and variable sedimentation rates are evaluated to demonstrate the robustness of the method. The CHO method is applied to the classical Late Triassic Newark depth rank series; the estimated sedimentation rates match closely with previously published sedimentation rates and provide a more highly time-resolved estimate (2,3). References: (1) Meyers, S.R., Sageman, B.B., Amer. J. Sci., 307, 773-792, 2007; (2) Kent, D.V., Olsen, P.E., Muttoni, G., Earth-Sci. Rev.166, 153-180, 2017; (3) Li, M., Zhang, Y., Huang, C., Ogg, J., Hinnov, L., Wang, Y., Zou, Z., Li, L., 2017. Earth Plant. Sc. Lett. doi:10.1016/j.epsl.2017.07.015

  1. Teachers' perceptions of students' mathematics proficiency may exacerbate early gender gaps in achievement.

    Science.gov (United States)

    Robinson-Cimpian, Joseph P; Lubienski, Sarah Theule; Ganley, Colleen M; Copur-Gencturk, Yasemin

    2014-04-01

    A recent wave of research suggests that teachers overrate the performance of girls relative to boys and hold more positive attitudes toward girls' mathematics abilities. However, these prior estimates of teachers' supposed female bias are potentially misleading because these estimates (and teachers themselves) confound achievement with teachers' perceptions of behavior and effort. Using data from the Early Childhood Longitudinal Study, Kindergarten Class of 1998-1999 (ECLS-K), Study 1 demonstrates that teachers actually rate boys' mathematics proficiency higher than that of girls when conditioning on both teachers' ratings of behavior and approaches to learning as well as past and current test scores. In other words, on average girls are only perceived to be as mathematically competent as similarly achieving boys when the girls are also seen as working harder, behaving better, and being more eager to learn. Study 2 uses mediation analysis with an instrumental-variables approach, as well as a matching strategy, to explore the extent to which this conditional underrating of girls may explain the widening gender gap in mathematics in early elementary school. We find robust evidence suggesting that underrating girls' mathematics proficiency accounts for a substantial portion of the development of the mathematics achievement gap between similarly performing and behaving boys and girls in the early grades. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  2. Preservice elementary teachers' actual and designated identities as teachers of science and teachers of students

    Science.gov (United States)

    Canipe, Martha Murray

    Preservice elementary teachers often have concerns about teaching science that may stem from a lack of confidence as teachers or their own negative experiences as learners of science. These concerns may lead preservice teachers to avoid teaching science or to teach it in a way that focuses on facts and vocabulary rather than engaging students in the doing of science. Research on teacher identity has suggested that being able to envision oneself as a teacher of science is an important part of becoming a teacher of science. Elementary teachers are generalists and as such rather than identifying themselves as teachers of particular content areas, they may identify more generally as teachers of students. This study examines three preservice teachers' identities as teachers of science and teachers of students and how these identities are enacted in their student teaching classrooms. Using a narrated identity framework, I explore stories told by preservice teachers, mentor teachers, student teaching supervisors, and science methods course instructors about who preservice teachers are as teachers of science and teachers of students. Identities are the stories that are told about who someone is or will become in relation to a particular context. Identities that are enacted are performances of the stories that are an identity. Stories were collected through interviews with each storyteller and in an unmoderated focus group with the three preservice teachers. In addition to sorting stories as being about teachers of science or students, the stories were categorized as being about preservice teachers in the present (actual identities) or in the future (designated identities). The preservice teachers were also observed teaching science lessons in their student teaching placements. These enactments of identities were analyzed in order to identify which aspects of the identity stories were reflected in the way preservice teachers taught their science lessons. I also analyzed the

  3. Options in Education: Program No. 88. Sex and Sexism in Education, Part II. Transcripts of a Weekly Series Broadcast by Member Stations of National Public Radio.

    Science.gov (United States)

    National Public Radio, Washington, DC.

    This booklet is a transcription of a program from the radio series, "Options in Education." It is part 2 of a two-part series dealing with sexism in education. It deals with sex discrimination in various aspects of public education, including textbooks, teacher promotion, sports programs and children's literature. There is also a…

  4. The Politics and Statistics of Value-Added Modeling for Accountability of Teacher Preparation Programs

    Science.gov (United States)

    Lincove, Jane Arnold; Osborne, Cynthia; Dillon, Amanda; Mills, Nicholas

    2014-01-01

    Despite questions about validity and reliability, the use of value-added estimation methods has moved beyond academic research into state accountability systems for teachers, schools, and teacher preparation programs (TPPs). Prior studies of value-added measurement for TPPs test the validity of researcher-designed models and find that measuring…

  5. Gender Inequality in Female-Dominated Occupation: The Earnings of Male and Female Teachers.

    Science.gov (United States)

    Verdugo, Richard R.; Schneider, Jeffrey M.

    1994-01-01

    Examines earnings differentials between male and female teachers, using data from the 1987 Schools and Staffing Survey by the U.S. Department of Education. The estimated cost of being a female teacher is 5% in annual contract salary. In the female-dominated teaching profession, despite regulated pay scales and other structures to ensure pay…

  6. Forecasting long memory series subject to structural change: A two-stage approach

    DEFF Research Database (Denmark)

    Papailias, Fotis; Dias, Gustavo Fruet

    2015-01-01

    A two-stage forecasting approach for long memory time series is introduced. In the first step, we estimate the fractional exponent and, by applying the fractional differencing operator, obtain the underlying weakly dependent series. In the second step, we produce multi-step-ahead forecasts...... for the weakly dependent series and obtain their long memory counterparts by applying the fractional cumulation operator. The methodology applies to both stationary and nonstationary cases. Simulations and an application to seven time series provide evidence that the new methodology is more robust to structural...

  7. Perceptions and Expectation of Palestinian Teachers towards Inclusive Education in Bethlehem District

    Science.gov (United States)

    Abu-Heran, N.; Abukhayran, A.; Domingo, J.; Perez-Garcia, M. P.

    2014-01-01

    Introduction: The study investigates about the reality of inclusive education in Palestine according to the opinion of their teachers. It is presented in the legislative and social framework of education in Palestine and compares it with current knowledge in inclusive education, from which a series of essential elements for inclusive education can…

  8. Estimating continuous monthly baseflow time series and their possible applications in the context of the ecological reserve

    CSIR Research Space (South Africa)

    Smakhtin, VU

    2001-04-01

    Full Text Available (river and groundwater) are, therefore, dependent. In this example, the assumption is that IFRs (river reserve flows) determine the extent to which groundwater resources may be impacted in the absence of any surface water resource development (the impacts... (IFRs) are used instead of reference natural streamflow time series. The corresponding groundwater storage time series will then represent the groundwater reserve. These storages may provisionally be called ?IFR driven?. Two component reserve time series...

  9. Radiation Resistance and Life Time Estimates at Cryogenic Temperatures of Series Produced By-Pass Diodes for the LHC Magnet Protection

    Science.gov (United States)

    Denz, R.; Gharib, A.; Hagedorn, D.

    2004-06-01

    For the protection of the LHC superconducting magnets about 2100 specially developed by-pass diodes have been manufactured in industry and more than one thousand of these diodes have been mounted into stacks and tested in liquid helium. By-pass diode samples, taken from the series production, have been submitted to irradiation tests at cryogenic temperatures together with some prototype diodes up to an accumulated dose of about 2 kGy and neutron fluences up to about 3.0 1013 n cm-2 with and without intermediate warm up to 300 K. The device characteristics of the diodes under forward bias and reverse bias have been measured at 77 K and ambient versus dose and the results are presented. Using a thermo-electrical model and new estimates for the expected dose in the LHC, the expected lifetime of the by-pass diodes has been estimated for various positions in the LHC arcs. It turns out that for all of the by-pass diodes across the arc elements the radiation resistance is largely sufficient. In the dispersion suppresser regions of the LHC, on a few diodes annual annealing during the shut down of the LHC must be applied or those diodes may need to be replaced after some time.

  10. Estimation of viscoelastic parameters in Prony series from shear wave propagation

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Jae-Wook; Hong, Jung-Wuk, E-mail: j.hong@kaist.ac.kr, E-mail: jwhong@alum.mit.edu [Department of Civil and Environmental Engineering, KAIST, 291 Deahak-ro, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); Lee, Hyoung-Ki; Choi, Kiwan [Health and Medical Equipment, Samsung Electronics, 1003 Daechi-dong, Gangnam-gu, Seoul 135-280 (Korea, Republic of)

    2016-06-21

    When acquiring accurate ultrasonic images, we must precisely estimate the mechanical properties of the soft tissue. This study investigates and estimates the viscoelastic properties of the tissue by analyzing shear waves generated through an acoustic radiation force. The shear waves are sourced from a localized pushing force acting for a certain duration, and the generated waves travel horizontally. The wave velocities depend on the mechanical properties of the tissue such as the shear modulus and viscoelastic properties; therefore, we can inversely calculate the properties of the tissue through parametric studies.

  11. Preparing culturally and linguistically diverse preservice Early Childhood teachers for field experience

    Directory of Open Access Journals (Sweden)

    Melinda Miller

    2016-07-01

    Full Text Available This article reports on an action research project focussed on preparing culturally and linguistically diverse (CALD preservice early childhood teachers for field experience. A series of targeted workshops delivered over one semester was designed to support the students to develop intercultural competence in relation to knowledge, attitude, skills and behaviours that contribute to success on field placement. Findings indicate that short-term initiatives targeted specifically to students’ identified needs and strengths can help to build intercultural competence for both students and teacher educators. For the participants, access to communication strategies, opportunities for rehearsal of teaching practice, and peer and academic support contributed to shifts in attitude, and the development of skills and new knowledge. New learnings for the teacher educators included challenging assumptions about CALD students’ sense of community and belonging in the university context.

  12. Activities for Studying Ponds (Limnology), Grade Level 5-6. Environmental Education Series, Bulletin No. 247-D.

    Science.gov (United States)

    Montgomery County Public Schools, Rockville, MD.

    This bulletin is one in a series of environmental education activity guides for grades K-12, developed and field-tested by teachers in the Montgomery County (Maryland) Public Schools. Primarily for use in the middle grades four through six, the guides are not intended to constitute complete units in themselves. They are, rather, a compilation of…

  13. Recurrent Neural Network Applications for Astronomical Time Series

    Science.gov (United States)

    Protopapas, Pavlos

    2017-06-01

    The benefits of good predictive models in astronomy lie in early event prediction systems and effective resource allocation. Current time series methods applicable to regular time series have not evolved to generalize for irregular time series. In this talk, I will describe two Recurrent Neural Network methods, Long Short-Term Memory (LSTM) and Echo State Networks (ESNs) for predicting irregular time series. Feature engineering along with a non-linear modeling proved to be an effective predictor. For noisy time series, the prediction is improved by training the network on error realizations using the error estimates from astronomical light curves. In addition to this, we propose a new neural network architecture to remove correlation from the residuals in order to improve prediction and compensate for the noisy data. Finally, I show how to set hyperparameters for a stable and performant solution correctly. In this work, we circumvent this obstacle by optimizing ESN hyperparameters using Bayesian optimization with Gaussian Process priors. This automates the tuning procedure, enabling users to employ the power of RNN without needing an in-depth understanding of the tuning procedure.

  14. Examination of the Financial Costs of Teacher Turnover in Mid-Sized Urban School Districts

    Science.gov (United States)

    Synar, Edwyna Anne

    2010-01-01

    It is estimated that 50% of beginning teachers leave the profession within the first five years on the job (Murnane, Singer, Willett, Kemple, & Olsen, 1991; Colbert & Wolff, 1992; Ingersoll, 2003b; Schlechty & Vance, 1981). When teachers depart, they take with them their knowledge of instructional techniques, students' learning styles, and…

  15. Reform of teacher education and teacher educator competences

    DEFF Research Database (Denmark)

    Rasmussen, Jens

    Despite it is well known known and recognized that teacher educators’ competences play a decisive role for the education of new teachers and also for the quality of the profession as such very little research is conducted on the competences of teacher educators and their training. It is also...... an established fact that the implementation of teacher education reforms to a large extent stands and falls with the competences of the teacher educators. Not least it is of importance that teacher educators possess the kind of competences that are needed to meet the intentions of a reform. Failing teacher...... educator competences might just as well be an explanation for frequent reforms in teacher education as it can be failure of the reforms themselves. Danish teacher education was in 2012 reformed for the third time in only fifteen years, but teacher educator competences were not mapped at all during...

  16. Off-line tracking of series parameters in distribution systems using AMI data

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Tess L.; Sun, Yannan; Schneider, Kevin

    2016-05-01

    Electric distribution systems have historically lacked measurement points, and equipment is often operated to its failure point, resulting in customer outages. The widespread deployment of sensors at the distribution level is enabling observability. This paper presents an off-line parameter value tracking procedure that takes advantage of the increasing number of measurement devices being deployed at the distribution level to estimate changes in series impedance parameter values over time. The tracking of parameter values enables non-diurnal and non-seasonal change to be flagged for investigation. The presented method uses an unbalanced Distribution System State Estimation (DSSE) and a measurement residual-based parameter estimation procedure. Measurement residuals from multiple measurement snapshots are combined in order to increase the effective local redundancy and improve the robustness of the calculations in the presence of measurement noise. Data from devices on the primary distribution system and from customer meters, via an AMI system, form the input data set. Results of simulations on the IEEE 13-Node Test Feeder are presented to illustrate the proposed approach applied to changes in series impedance parameters. A 5% change in series resistance elements can be detected in the presence of 2% measurement error when combining less than 1 day of measurement snapshots into a single estimate.

  17. Academic gender stereotypes of pre-service teachers

    Directory of Open Access Journals (Sweden)

    Ćirović Ivana

    2013-01-01

    Full Text Available This research was aimed at studying the content of academic gender stereotypes of pre-service teachers who are being prepared for working in different cycles of education. The sample included 408 students of teaching programmes of the Teacher Training College, Faculty of Mathematics and Faculty of Philology in Belgrade. It has been established that future class and subject teachers have gender stereotypes about the interests and achievements of students in different school subjects. pre-service teachers from both groups are of the opinion that girls get interested more easily than boys in the majority of school subjects, as well as that girls are more talented for the subjects in the field of humanities and languages, while boys are more talented for the subjects in the field of sciences. Pre-service teachers estimate that boys typically have a low achievement in languages, arts and music, while girls have a low achievement in physics, computer science, technical sciences and physical education. Since teachers’ gender stereotypes can affect students’ achievement, educational and career choices, it is important to raise awareness about the content and consequences of such beliefs in teachers and focus on certain actions towards their altering. [Projekat Ministarstva nauke Republike Srbije, br. 179034: Od podsticanja inicijative, saradnje, stvaralaštva u obrazovanju do novih uloga i identiteta u društvu i br. 47008: Unapređivanje kvaliteta i dostupnosti obrazovanja u procesima modernizacije Srbije

  18. Enlist micros: Training science teachers to use microcomputers

    Science.gov (United States)

    Baird, William E.; Ellis, James D.; Kuerbis, Paul J.

    A National Science Foundation grant to the Biological Sciences Curriculum Study (BSCS) at The Colorado College supported the design and production of training materials to encourage literacy of science teachers in the use of microcomputers. ENLIST Micros is based on results of a national needs assessment that identified 22 compentencies needed by K-12 science teachers to use microcomputers for instruction. A writing team developed the 16-hour training program in the summer of 1985, and field-test coordinators tested it with 18 preservice or in-service groups during the 1985-86 academic year at 15 sites within the United States. The training materials consist of video programs, interactive computer disks for the Apple II series microcomputer, a training manual for participants, and a guide for the group leader. The experimental materials address major areas of educational computing: awareness, applications, implementation, evaluation, and resources. Each chapter contains activities developed for this program, such as viewing video segments of science teachers who are using computers effectively and running commercial science and training courseware. Role playing and small-group interaction help the teachers overcome their reluctance to use computers and plan for effective implementation of microcomputers in the school. This study examines the implementation of educational computing among 47 science teachers who completed the ENLIST Micros training at a southern university. We present results of formative evaluation for that site. Results indicate that both elementary and secondary teachers benefit from the training program and demonstrate gains in attitudes toward computer use. Participating teachers said that the program met its stated objectives and helped them obtain needed skills. Only 33 percent of these teachers, however, reported using computers one year after the training. In June 1986, the BSCS initiated a follow up to the ENLIST Micros curriculum to

  19. An Illustration of Generalised Arma (garma) Time Series Modeling of Forest Area in Malaysia

    Science.gov (United States)

    Pillai, Thulasyammal Ramiah; Shitan, Mahendran

    Forestry is the art and science of managing forests, tree plantations, and related natural resources. The main goal of forestry is to create and implement systems that allow forests to continue a sustainable provision of environmental supplies and services. Forest area is land under natural or planted stands of trees, whether productive or not. Forest area of Malaysia has been observed over the years and it can be modeled using time series models. A new class of GARMA models have been introduced in the time series literature to reveal some hidden features in time series data. For these models to be used widely in practice, we illustrate the fitting of GARMA (1, 1; 1, δ) model to the Annual Forest Area data of Malaysia which has been observed from 1987 to 2008. The estimation of the model was done using Hannan-Rissanen Algorithm, Whittle's Estimation and Maximum Likelihood Estimation.

  20. Estimating Dynamical Systems: Derivative Estimation Hints from Sir Ronald A. Fisher

    Science.gov (United States)

    Deboeck, Pascal R.

    2010-01-01

    The fitting of dynamical systems to psychological data offers the promise of addressing new and innovative questions about how people change over time. One method of fitting dynamical systems is to estimate the derivatives of a time series and then examine the relationships between derivatives using a differential equation model. One common…

  1. Que bonito es leer! III. Guia para el maestro, segunda parte (How Nice It Is to Read! III. Teacher's Guide, Part 2).

    Science.gov (United States)

    Dissemination and Assessment Center for Bilingual Education, Austin, TX.

    This is the teacher's guide to the third and last unit in a series designed to provide the Spanish-speaking child with a complete language arts and reading program for grades 1-3. The unit focuses on the development of decoding, encoding, comprehension, and interpretation skills. The teacher's guide for the third grade workbook contains a series…

  2. Que bonito es leer! III. Guia para el maestro, primera parte (How Nice It Is to Read! III. Teacher's Guide, Part 1).

    Science.gov (United States)

    Dissemination and Assessment Center for Bilingual Education, Austin, TX.

    This is the teacher's guide to the third and last unit in a series designed to provide the Spanish-speaking child with a complete language arts and reading program for grades 1-3. The unit focuses on the development of decoding, encoding, comprehension, and interpretation skills. This teacher's guide for the third grade workbook contains a series…

  3. Photovoltaic module diagnostics by series resistance monitoring and temperature and rated power estimation

    DEFF Research Database (Denmark)

    Sera, Dezso; Teodorescu, Remus; Rodriguez, Pedro

    2008-01-01

    One of the most important parameters, which characterize a photovoltaic panel health state, is its series resistance. An increase of this normally indicates bad contacts between cells or panels. Another important property, which characterizes the aging of the panel is the reduction of its MPP power...

  4. Estimating the Entropy of Binary Time Series: Methodology, Some Theory and a Simulation Study

    Directory of Open Access Journals (Sweden)

    Elie Bienenstock

    2008-06-01

    Full Text Available Partly motivated by entropy-estimation problems in neuroscience, we present a detailed and extensive comparison between some of the most popular and effective entropy estimation methods used in practice: The plug-in method, four different estimators based on the Lempel-Ziv (LZ family of data compression algorithms, an estimator based on the Context-Tree Weighting (CTW method, and the renewal entropy estimator. METHODOLOGY: Three new entropy estimators are introduced; two new LZ-based estimators, and the “renewal entropy estimator,” which is tailored to data generated by a binary renewal process. For two of the four LZ-based estimators, a bootstrap procedure is described for evaluating their standard error, and a practical rule of thumb is heuristically derived for selecting the values of their parameters in practice. THEORY: We prove that, unlike their earlier versions, the two new LZ-based estimators are universally consistent, that is, they converge to the entropy rate for every finite-valued, stationary and ergodic process. An effective method is derived for the accurate approximation of the entropy rate of a finite-state hidden Markov model (HMM with known distribution. Heuristic calculations are presented and approximate formulas are derived for evaluating the bias and the standard error of each estimator. SIMULATION: All estimators are applied to a wide range of data generated by numerous different processes with varying degrees of dependence and memory. The main conclusions drawn from these experiments include: (i For all estimators considered, the main source of error is the bias. (ii The CTW method is repeatedly and consistently seen to provide the most accurate results. (iii The performance of the LZ-based estimators is often comparable to that of the plug-in method. (iv The main drawback of the plug-in method is its computational inefficiency; with small word-lengths it fails to detect longer-range structure in

  5. Training Elementary Teachers to Prepare Students for High School Authentic Scientific Research

    Science.gov (United States)

    Danch, J. M.

    2017-12-01

    The Woodbridge Township New Jersey School District has a 4-year high school Science Research program that depends on the enrollment of students with the prerequisite skills to conduct authentic scientific research at the high school level. A multifaceted approach to training elementary teachers in the methods of scientific investigation, data collection and analysis and communication of results was undertaken in 2017. Teachers of predominately grades 4 and 5 participated in hands on workshops at a Summer Tech Academy, an EdCamp, a District Inservice Day and a series of in-class workshops for teachers and students together. Aspects of the instruction for each of these activities was facilitated by high school students currently enrolled in the High School Science Research Program. Much of the training activities centered around a "Learning With Students" model where teachers and their students simultaneously learn to perform inquiry activities and conduct scientific research fostering inquiry as it is meant to be: where participants produce original data are not merely working to obtain previously determined results.

  6. Glacier Volume Change Estimation Using Time Series of Improved Aster Dems

    Science.gov (United States)

    Girod, Luc; Nuth, Christopher; Kääb, Andreas

    2016-06-01

    Volume change data is critical to the understanding of glacier response to climate change. The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) system embarked on the Terra (EOS AM-1) satellite has been a unique source of systematic stereoscopic images covering the whole globe at 15m resolution and at a consistent quality for over 15 years. While satellite stereo sensors with significantly improved radiometric and spatial resolution are available to date, the potential of ASTER data lies in its long consistent time series that is unrivaled, though not fully exploited for change analysis due to lack of data accuracy and precision. Here, we developed an improved method for ASTER DEM generation and implemented it in the open source photogrammetric library and software suite MicMac. The method relies on the computation of a rational polynomial coefficients (RPC) model and the detection and correction of cross-track sensor jitter in order to compute DEMs. ASTER data are strongly affected by attitude jitter, mainly of approximately 4 km and 30 km wavelength, and improving the generation of ASTER DEMs requires removal of this effect. Our sensor modeling does not require ground control points and allows thus potentially for the automatic processing of large data volumes. As a proof of concept, we chose a set of glaciers with reference DEMs available to assess the quality of our measurements. We use time series of ASTER scenes from which we extracted DEMs with a ground sampling distance of 15m. Our method directly measures and accounts for the cross-track component of jitter so that the resulting DEMs are not contaminated by this process. Since the along-track component of jitter has the same direction as the stereo parallaxes, the two cannot be separated and the elevations extracted are thus contaminated by along-track jitter. Initial tests reveal no clear relation between the cross-track and along-track components so that the latter seems not to be

  7. Bias Correction with Jackknife, Bootstrap, and Taylor Series

    OpenAIRE

    Jiao, Jiantao; Han, Yanjun; Weissman, Tsachy

    2017-01-01

    We analyze the bias correction methods using jackknife, bootstrap, and Taylor series. We focus on the binomial model, and consider the problem of bias correction for estimating $f(p)$, where $f \\in C[0,1]$ is arbitrary. We characterize the supremum norm of the bias of general jackknife and bootstrap estimators for any continuous functions, and demonstrate the in delete-$d$ jackknife, different values of $d$ may lead to drastically different behavior in jackknife. We show that in the binomial ...

  8. Anxiety as Related to Thinking and Forgetting. What Research Says to the Teacher Series, Number 30.

    Science.gov (United States)

    Lighthall, Frederick F.

    The purpose of this pamphlet is to increase teachers' comprehension of anxiety and its relation to children's thinking and forgetting, to their problem solving ability and their sense of competence. The pamphlet describes four parts of the anxiety experience: 1) the anxiety cue, the particular thought, memory, or sensation which precipitates the…

  9. Bayesian Nonparametric Mixture Estimation for Time-Indexed Functional Data in R

    Directory of Open Access Journals (Sweden)

    Terrance D. Savitsky

    2016-08-01

    Full Text Available We present growfunctions for R that offers Bayesian nonparametric estimation models for analysis of dependent, noisy time series data indexed by a collection of domains. This data structure arises from combining periodically published government survey statistics, such as are reported in the Current Population Study (CPS. The CPS publishes monthly, by-state estimates of employment levels, where each state expresses a noisy time series. Published state-level estimates from the CPS are composed from household survey responses in a model-free manner and express high levels of volatility due to insufficient sample sizes. Existing software solutions borrow information over a modeled time-based dependence to extract a de-noised time series for each domain. These solutions, however, ignore the dependence among the domains that may be additionally leveraged to improve estimation efficiency. The growfunctions package offers two fully nonparametric mixture models that simultaneously estimate both a time and domain-indexed dependence structure for a collection of time series: (1 A Gaussian process (GP construction, which is parameterized through the covariance matrix, estimates a latent function for each domain. The covariance parameters of the latent functions are indexed by domain under a Dirichlet process prior that permits estimation of the dependence among functions across the domains: (2 An intrinsic Gaussian Markov random field prior construction provides an alternative to the GP that expresses different computation and estimation properties. In addition to performing denoised estimation of latent functions from published domain estimates, growfunctions allows estimation of collections of functions for observation units (e.g., households, rather than aggregated domains, by accounting for an informative sampling design under which the probabilities for inclusion of observation units are related to the response variable. growfunctions includes plot

  10. Teacher training: the quick fix that stuck.

    Science.gov (United States)

    Coldevin, G

    1988-01-01

    Of all the strategies for coping with teacher shortages that have been attempted, the effort that has gained the most ground in the past 20 years involves recruiting untrained or unqualified teachers pressing them into service, and then bringing them up to pedagogical or academic certification through distance education. The benefits of this approach include: for teachers, home-based study means attaining professional certification or academic upgrading without interrupting earnings; in-service training obviates the problem of finding substitute teachers who may have poorer qualifications than the teachers they are replacing; in-situ training reduces the possibility of urban migration that may result when college-based trainees do not want to return to their rural posts; and larger numbers of teachers can be served at 1 time and at lower costs than with campus-based instruction. According to the available studies, training costs for distance education students are typically 1/4 to 1/2 as expensive as conventional instruction. At least 50 3rd world countries are estimated to be involved in some form of distance teacher training. Mostly, countries combine correspondence with broadcasting and other support media, correspondence with occasional face-to-face sessions, and the 3-way combination of print/broadcasting/occasional residential teaching approaches. The broadcast medium typically is radio, but some programs, particularly programs offered by distance education universities, use television also. Tutorial counseling and local resource center support vary considerably and represent the most pressing challenges to the bulk of operations. 4 systems initiated during the 1980s in Pakistan, Burma, Zimbabwe, and Kenya are presented to illustrate the need for distance education training and the diversity of distance education methods.

  11. The role of teacher in motivating pupils to learn french in Slovenia

    Directory of Open Access Journals (Sweden)

    Darja Premrl

    2011-12-01

    Full Text Available French language teachers in Slovene elementary and high schools think that the teachers must motivate pupils with different approaches to work in the classroom. They also estimate that if the student isn't motivated to work in the classroom, teacher's effort could improve the motivation. Teachers, therefore, believe in their work, in their knowledge and competences to present French language to the pupils in the way they enjoy studying it, and that their way of work improves interest for the knowledge/learning of French language. Nevertheless, 78 % of teachers involved in this research think that a workshop about motivation with the examples from the good practice could be of great use to them. The analysis shows that teachers like to use student's book in their work and that they most often motivate pupils with their own excitement about the topic. The fact is that the motivation is a dynamic process which changes in time and in place. Teacher is a part of that process, but he/she is not the only one responsible for its outcome.

  12. Healthcare Coinsurance Elasticity Coefficient Estimation Using Monthly Cross-sectional, Time-series Claims Data.

    Science.gov (United States)

    Scoggins, John F; Weinberg, Daniel A

    2017-06-01

    Published estimates of the healthcare coinsurance elasticity coefficient have typically relied on annual observations of individual healthcare expenditures even though health plan membership and expenditures are traditionally reported in monthly units and several studies have stressed the need for demand models to recognize the episodic nature of healthcare. Summing individual healthcare expenditures into annual observations complicates two common challenges of statistical inference, heteroscedasticity, and regressor endogeneity. This paper estimates the elasticity coefficient using a monthly panel data model that addresses the heteroscedasticity and endogeneity problems with relative ease. Healthcare claims data from employees of King County, Washington, during 2005 to 2011 were used to estimate the mean point elasticity coefficient: -0.314 (0.015 standard error) to -0.145 (0.015 standard error) depending on model specification. These estimates bracket the -0.2 point estimate (range: -0.22 to -0.17) derived from the famous Rand Health Insurance Experiment. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  13. Overcoming equifinality: Leveraging long time series for stream metabolism estimation

    Science.gov (United States)

    Appling, Alison; Hall, Robert O.; Yackulic, Charles B.; Arroita, Maite

    2018-01-01

    The foundational ecosystem processes of gross primary production (GPP) and ecosystem respiration (ER) cannot be measured directly but can be modeled in aquatic ecosystems from subdaily patterns of oxygen (O2) concentrations. Because rivers and streams constantly exchange O2 with the atmosphere, models must either use empirical estimates of the gas exchange rate coefficient (K600) or solve for all three parameters (GPP, ER, and K600) simultaneously. Empirical measurements of K600 require substantial field work and can still be inaccurate. Three-parameter models have suffered from equifinality, where good fits to O2 data are achieved by many different parameter values, some unrealistic. We developed a new three-parameter, multiday model that ensures similar values for K600 among days with similar physical conditions (e.g., discharge). Our new model overcomes the equifinality problem by (1) flexibly relating K600 to discharge while permitting moderate daily deviations and (2) avoiding the oft-violated assumption that residuals in O2 predictions are uncorrelated. We implemented this hierarchical state-space model and several competitor models in an open-source R package, streamMetabolizer. We then tested the models against both simulated and field data. Our new model reduces error by as much as 70% in daily estimates of K600, GPP, and ER. Further, accuracy benefits of multiday data sets require as few as 3 days of data. This approach facilitates more accurate metabolism estimates for more streams and days, enabling researchers to better quantify carbon fluxes, compare streams by their metabolic regimes, and investigate controls on aquatic activity.

  14. Argumentation in Science Teacher Education: The simulated jury as a resource for teaching and learning

    Science.gov (United States)

    Drumond Vieira, Rodrigo; da Rocha Bernardo, José Roberto; Evagorou, Maria; Florentino de Melo, Viviane

    2015-05-01

    In this article, we focus on the contributions that a simulated jury-based activity might have for pre-service teachers, especially for their active participation and learning in teacher education. We observed a teacher educator using a series of simulated juries as teaching resources to help pre-service teachers develop their pedagogical knowledge and their argumentation abilities in a physics teacher methods course. For the purposes of this article, we have selected one simulated jury-based activity, comprising two opposed groups of pre-service teachers that presented aspects that hinder the teachers' development of professional knowledge (against group) and aspects that allow this development (favor group). After the groups' presentations, a group of judges was formed to evaluate the discussion. We applied a multi-level method for discourse analysis and the results showed that (1) the simulated jury afforded the pre-service teachers to position themselves as active knowledge producers; (2) the teacher acted as 'animator' of the pre-service teachers' actions, showing responsiveness to the emergence of circumstantial teaching and learning opportunities and (3) the simulated jury culminated in the judges' identification of the pattern 'concrete/obstacles-ideological/possibilities' in the groups' responses, which was elaborated by the teacher for the whole class. Implications from this study include using simulated juries for teaching and learning and for the development of the pre-service teachers' argumentative abilities. The potential of simulated juries to improve teaching and learning needs to be further explored in order to inform the uses and reflections of this resource in science education.

  15. multivariate time series modeling of selected childhood diseases

    African Journals Online (AJOL)

    2016-06-17

    Jun 17, 2016 ... KEYWORDS: Multivariate Approach, Pre-whitening, Vector Time Series, .... Alternatively, the process may be written in mean adjusted form as .... The AIC criterion asymptotically over estimates the order with positive probability, whereas the BIC and HQC criteria ... has the same asymptotic distribution as Ǫ.

  16. Observed Characteristics and Teacher Quality: Impacts of Sample Selection on a Value Added Model

    Science.gov (United States)

    Winters, Marcus A.; Dixon, Bruce L.; Greene, Jay P.

    2012-01-01

    We measure the impact of observed teacher characteristics on student math and reading proficiency using a rich dataset from Florida. We expand upon prior work by accounting directly for nonrandom attrition of teachers from the classroom in a sample selection framework. We find evidence that sample selection is present in the estimation of the…

  17. Teachers' Views on Risk Factors for Problematic School Absenteeism in Swedish Primary School Students

    Science.gov (United States)

    Gren-Landell, Malin; Ekerfelt Allvin, Cornelia; Bradley, Maria; Andersson, Maria; Andersson, Gerhard

    2015-01-01

    In the present online survey, 158 teachers in regular and special education teaching in grades six to nine were asked to rate the importance of probable reasons for problematic school absenteeism. On average, the teachers estimated that among their students, 19 students had presented with problematic school absenteeism over the last five years.…

  18. Generation and Validation of Spatial Distribution of Hourly Wind Speed Time-Series using Machine Learning

    International Nuclear Information System (INIS)

    Veronesi, F; Grassi, S

    2016-01-01

    Wind resource assessment is a key aspect of wind farm planning since it allows to estimate the long term electricity production. Moreover, wind speed time-series at high resolution are helpful to estimate the temporal changes of the electricity generation and indispensable to design stand-alone systems, which are affected by the mismatch of supply and demand. In this work, we present a new generalized statistical methodology to generate the spatial distribution of wind speed time-series, using Switzerland as a case study. This research is based upon a machine learning model and demonstrates that statistical wind resource assessment can successfully be used for estimating wind speed time-series. In fact, this method is able to obtain reliable wind speed estimates and propagate all the sources of uncertainty (from the measurements to the mapping process) in an efficient way, i.e. minimizing computational time and load. This allows not only an accurate estimation, but the creation of precise confidence intervals to map the stochasticity of the wind resource for a particular site. The validation shows that machine learning can minimize the bias of the wind speed hourly estimates. Moreover, for each mapped location this method delivers not only the mean wind speed, but also its confidence interval, which are crucial data for planners. (paper)

  19. Generation and Validation of Spatial Distribution of Hourly Wind Speed Time-Series using Machine Learning

    Science.gov (United States)

    Veronesi, F.; Grassi, S.

    2016-09-01

    Wind resource assessment is a key aspect of wind farm planning since it allows to estimate the long term electricity production. Moreover, wind speed time-series at high resolution are helpful to estimate the temporal changes of the electricity generation and indispensable to design stand-alone systems, which are affected by the mismatch of supply and demand. In this work, we present a new generalized statistical methodology to generate the spatial distribution of wind speed time-series, using Switzerland as a case study. This research is based upon a machine learning model and demonstrates that statistical wind resource assessment can successfully be used for estimating wind speed time-series. In fact, this method is able to obtain reliable wind speed estimates and propagate all the sources of uncertainty (from the measurements to the mapping process) in an efficient way, i.e. minimizing computational time and load. This allows not only an accurate estimation, but the creation of precise confidence intervals to map the stochasticity of the wind resource for a particular site. The validation shows that machine learning can minimize the bias of the wind speed hourly estimates. Moreover, for each mapped location this method delivers not only the mean wind speed, but also its confidence interval, which are crucial data for planners.

  20. Taylor Series-Based Long-Term Creep-Life Prediction of Alloy 617

    International Nuclear Information System (INIS)

    Yin, Song Nan; Kim, Woo Gon; Kim, Yong Wan; Park, Jae Young; Kim, Soen Jin

    2010-01-01

    In this study, a Taylor series (T-S) model based on the Arrhenius, McVetty, and Monkman-Grant equations was developed using a mathematical analysis. In order to reduce fitting errors, the McVetty equation was transformed by considering the first three terms of the Taylor series equation. The model parameters were accurately determined by a statistical technique of maximum likelihood estimation, and this model was applied to the creep data of alloy 617. The T-S model results showed better agreement with the experimental data than other models such as the Eno, exponential, and L-M models. In particular, the T-S model was converted into an isothermal Taylor series (IT-S) model that can predict the creep strength at a given temperature. It was identified that the estimations obtained using the converted ITS model was better than that obtained using the T-S model for predicting the long-term creep life of alloy 617

  1. The Effect of Teacher Training on the Knowledge of Positive Behavior Support and the Quality of Behavior Intervention Plans: A Preliminary Study in Taiwan

    Science.gov (United States)

    Wu, Pei-Fang

    2017-01-01

    The purpose of this study was to investigate whether through a series of teacher training. The participants could acquire better knowledge on Positive Behavior Support (PBS), and develop high quality behavior intervention plans. Thirty-six teachers from three public schools participated in the study. The competency-based training consisted of 12…

  2. Teaching with Gender. European Women’s Studiesin International and Interdisciplinary Classrooms.A book series by ATHENA : Teaching Gender in Social Work

    OpenAIRE

    2009-01-01

    How can educators (teachers, professors, trainers) address issues of gender, women, gender roles, feminism and gender equality? The ATHENA thematic network brings together specialists in women’s and gender studies, feminist research, women’s rights, gender equality and diversity. In the book series ‘ Teaching with Gender’ the partners in this network have collected articles on a wide range of teaching practices in the field of gender. The books in this series address challenges and possibilit...

  3. The Figured Worlds of High School Science Teachers: Uncovering Three-Dimensional Assessment Decisions

    Science.gov (United States)

    Ewald, Megan

    As a result of recent mandates of the Next Generation Science Standards, assessments are a "system of meaning" amidst a paradigm shift toward three-dimensional assessments. This study is motivated by two research questions: 1) how do high school science teachers describe their processes of decision-making in the development and use of three-dimensional assessments and 2) how do high school science teachers negotiate their identities as assessors in designing three-dimensional assessments. An important factor in teachers' assessment decision making is how they identify themselves as assessors. Therefore, this study investigated the teachers' roles as assessors through the Sociocultural Identity Theory. The most important contribution from this study is the emergent teacher assessment sub-identities: the modifier-recycler , the feeler-finder, and the creator. Using a qualitative phenomenological research design, focus groups, three-series interviews, think-alouds, and document analysis were utilized in this study. These qualitative methods were chosen to elicit rich conversations among teachers, make meaning of the teachers' experiences through in-depth interviews, amplify the thought processes of individual teachers while making assessment decisions, and analyze assessment documents in relation to teachers' perspectives. The findings from this study suggest that--of the 19 participants--only two teachers could consistently be identified as creators and aligned their assessment practices with NGSS. However, assessment sub-identities are not static and teachers may negotiate their identities from one moment to the next within socially constructed realms of interpretation known as figured worlds. Because teachers are positioned in less powerful figured worlds within the dominant discourse of standardization, this study raises awareness as to how the external pressures from more powerful figured worlds socially construct teachers' identities as assessors. For teachers

  4. Fostering Creativity from an Emotional Perspective: Do Teachers Recognise and Handle Students' Emotions?

    Science.gov (United States)

    Siu, Kin Wai; Wong, Yi Lin

    2016-01-01

    Emotions have a significant effect on the processes of designing and creative thinking. In an educational context, some emotions may even be detrimental to creativity. To further explore the link between creativity and emotion, a series of interviews were conducted with design and technology (D&T) teachers in Singapore, Hong Kong and Beijing…

  5. Iranian Language Teachers' and Students' Perspectives on Top Notch Series (2nd Edition) at Intermediate Level

    Science.gov (United States)

    Azadsarv, Mehdi; Tahriri, Abdorreza

    2014-01-01

    As the means of transferring knowledge between teachers and students, coursebooks play a significant role in educational practices all over the world. Evaluation of coursebooks is also of great significance as it manages to a better understanding of the nature of a specific teaching/learning situation. The present study is an attempt to evaluate…

  6. The prevalence and correlates of severe depression in a cohort of Mexican teachers.

    Science.gov (United States)

    Soria-Saucedo, Rene; Lopez-Ridaura, Ruy; Lajous, Martin; Wirtz, Veronika J

    2018-07-01

    Depression is among the 10 major causes of disability in Mexico. Yet, local contextual factors associated to the disorder remain poorly understood. We measured the impact of several factors on severe depression such as demographics, pharmacotherapy, multimorbidity, and unhealthy behaviors in Mexican teachers. A total of 43,845 Mexican female teachers from 12 Mexican states answered the Patient Health Questionnaire (PHQ9). Data were part the Mexican Teacher's Cohort prospective study, the largest ongoing cohort study in Latin America. Unadjusted and adjusted estimates assessed the impact of several contextual factors between severe versus mild-no depression cases. In total 7026 teachers (16%) had a PHQ9 score compatible with severe depression. From them, only 17% received psychotropics, compared to 60% for those with a formal diagnosis. Less than 5% of teachers with PHQ9 scores compatible with severe depression had a formal diagnosis. Adjusted analysis reported higher odds of pharmacotherapy, having ≥ 3 comorbidities, higher levels of couple, family and work stress, fewer hours of vigorous physical activity, higher alcohol consumption, and smoking as risk factors for severe depression. Also, rural residents of northern and center states appeared more severely depressed compared to their urban counterparts. On average, the PHQ9 scores differed by ~ 10 points between severe and mild-no depressed teachers. A cross-sectional design. Also, the study focused on female teachers between ages 25 and 74 years old, reducing the generalizability of the estimates. Under-diagnosis of clinical depression in Mexican teachers is concerning. Unhealthy behavior is associated with severe depression. The information collected in this study represents an opportunity to build prevention mechanisms of depression in high-risk subgroups of female educators and warrants improving access to mental care in Mexico. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. Modelling of extreme rainfall events in Peninsular Malaysia based on annual maximum and partial duration series

    Science.gov (United States)

    Zin, Wan Zawiah Wan; Shinyie, Wendy Ling; Jemain, Abdul Aziz

    2015-02-01

    In this study, two series of data for extreme rainfall events are generated based on Annual Maximum and Partial Duration Methods, derived from 102 rain-gauge stations in Peninsular from 1982-2012. To determine the optimal threshold for each station, several requirements must be satisfied and Adapted Hill estimator is employed for this purpose. A semi-parametric bootstrap is then used to estimate the mean square error (MSE) of the estimator at each threshold and the optimal threshold is selected based on the smallest MSE. The mean annual frequency is also checked to ensure that it lies in the range of one to five and the resulting data is also de-clustered to ensure independence. The two data series are then fitted to Generalized Extreme Value and Generalized Pareto distributions for annual maximum and partial duration series, respectively. The parameter estimation methods used are the Maximum Likelihood and the L-moment methods. Two goodness of fit tests are then used to evaluate the best-fitted distribution. The results showed that the Partial Duration series with Generalized Pareto distribution and Maximum Likelihood parameter estimation provides the best representation for extreme rainfall events in Peninsular Malaysia for majority of the stations studied. Based on these findings, several return values are also derived and spatial mapping are constructed to identify the distribution characteristic of extreme rainfall in Peninsular Malaysia.

  8. Local Amenities, Unobserved Quality, and Market Clearing: Adjusting Teacher Compensation to Provide Equal Education Opportunities

    Science.gov (United States)

    Tuck, Bradford; Berman, Matthew; Hill, Alexandra

    2009-01-01

    Local school districts differ in their ability to pay for teacher quality, and in the amenities they offer as places to live and work. Market clearing with heterogeneous quality yields geographically varying teacher salary levels that confound scarcity with unobserved differences in quality. The paper discusses identification and estimation of a…

  9. Teacher Leadership: Teacher Self-Assessment Tool

    Science.gov (United States)

    American Institutes for Research, 2017

    2017-01-01

    As interest in teacher leadership has grown, many leading organizations have developed tools and guidance to support schools, districts, and teacher leaders themselves. In collaboration and consultation with the Regional Educational Laboratory (REL) Midwest Educator Effectiveness Research Alliance, REL Midwest and the Center on Great Teachers and…

  10. Analysis of the Command and Control Segment (CCS) attitude estimation algorithm

    Science.gov (United States)

    Stockwell, Catherine

    1993-01-01

    This paper categorizes the qualitative behavior of the Command and Control Segment (CCS) differential correction algorithm as applied to attitude estimation using simultaneous spin axis sun angle and Earth cord length measurements. The categories of interest are the domains of convergence, divergence, and their boundaries. Three series of plots are discussed that show the dependence of the estimation algorithm on the vehicle radius, the sun/Earth angle, and the spacecraft attitude. Common qualitative dynamics to all three series are tabulated and discussed. Out-of-limits conditions for the estimation algorithm are identified and discussed.

  11. Teacher expertise

    DEFF Research Database (Denmark)

    Rasmussen, Jens

    Teacher Expertise: How to improve the relationship between Theory and Practice in Teacher Education Jens Rasmussen, Department of Education, Aarhus University In several studies and reports it has been nailed over and over that teachers’ matter. So this is not the question in this study. The ques......Teacher Expertise: How to improve the relationship between Theory and Practice in Teacher Education Jens Rasmussen, Department of Education, Aarhus University In several studies and reports it has been nailed over and over that teachers’ matter. So this is not the question in this study....... The question is how teacher preparation leads to effective teachers. The study Expert in Teaching paid special attention to the intention of connecting coursework more directly to practice in pre-service teacher education. The overall objective of the study was to strengthen the relationship between theory...... that the three parties (college teachers, practice teachers and teacher students) found it difficult to perform and maintain their different roles....

  12. Fourier series

    CERN Document Server

    Tolstov, Georgi P

    1962-01-01

    Richard A. Silverman's series of translations of outstanding Russian textbooks and monographs is well-known to people in the fields of mathematics, physics, and engineering. The present book is another excellent text from this series, a valuable addition to the English-language literature on Fourier series.This edition is organized into nine well-defined chapters: Trigonometric Fourier Series, Orthogonal Systems, Convergence of Trigonometric Fourier Series, Trigonometric Series with Decreasing Coefficients, Operations on Fourier Series, Summation of Trigonometric Fourier Series, Double Fourie

  13. The ESO Educational Office Reaches Out towards Europe's Teachers

    Science.gov (United States)

    2001-12-01

    ESA/ESO Astronomy Exercises Provide a Taste of Real Astronomy [1] Summary The European Southern Observatory (ESO) has been involved in many Europe-wide educational projects during the past years, in particular within European Science Weeks sponsored by the European Commission (EC). In order to further enhance the significant educational potential inherent in the numerous scientific endeavours now carried out by Europe's astronomers with ESO front-line telescope facilities, it has been decided to set up an Educational Office within the ESO EPR Department. It will from now on work closely with astronomy-oriented teachers, in particular at the high-school level , providing support, inspiration and new materials. Much of this interaction will happen via the European Association for Astronomy Education (EAAE) In this context, and in collaboration with the European Space Agency (ESA) , the first instalments of the "ESA/ESO Astronomy Exercise Series" have just been published, on the web ( http://www.astroex.org ) and in print (6 booklets totalling 100 pages; provided free-of-charge to teachers on request). They allow 16-19 year old students to gain exciting hands-on experience in astronomy, making realistic calculations with data obtained from observations by some of the world's best telescopes, the NASA/ESA Hubble Space Telescope (HST) and ESO's Very Large Telescope (VLT) . PR Photo 36/01 : The "ESA/ESO Astronomy Exercise Series" . Educational projects at ESO The European Southern Observatory (ESO) , through its Education and Public Relations Department (EPR) , has long been involved in educational activities, in particular by means of Europe-wide projects during successive European Science Weeks , with support from the European Commission (EC) . A most visible outcome has been the creation of the trailblazing European Association for Astronomy Education (EAAE) - this was first discussed at an international meeting at the ESO Headquarters in November 1994 with the

  14. Prediction in Partial Duration Series With Generalized Pareto-Distributed Exceedances

    DEFF Research Database (Denmark)

    Rosbjerg, Dan; Madsen, Henrik; Rasmussen, Peter Funder

    1992-01-01

    As a generalization of the common assumption of exponential distribution of the exceedances in Partial duration series the generalized Pareto distribution has been adopted. Estimators for the parameters are presented using estimation by both method of moments and probability-weighted moments...... distributions (with physically justified upper limit) the correct exceedance distribution should be applied despite a possible acceptance of the exponential assumption by a test of significance....

  15. Particle Markov Chain Monte Carlo Techniques of Unobserved Component Time Series Models Using Ox

    DEFF Research Database (Denmark)

    Nonejad, Nima

    This paper details Particle Markov chain Monte Carlo techniques for analysis of unobserved component time series models using several economic data sets. PMCMC combines the particle filter with the Metropolis-Hastings algorithm. Overall PMCMC provides a very compelling, computationally fast...... and efficient framework for estimation. These advantages are used to for instance estimate stochastic volatility models with leverage effect or with Student-t distributed errors. We also model changing time series characteristics of the US inflation rate by considering a heteroskedastic ARFIMA model where...

  16. Data Series Subtraction with Unknown and Unmodeled Background Noise

    Science.gov (United States)

    Vitale, Stefano; Congedo, Giuseppe; Dolesi, Rita; Ferroni, Valerio; Hueller, Mauro; Vetrugno, Daniele; Weber, William Joseph; Audley, Heather; Danzmann, Karsten; Diepholz, Ingo; hide

    2014-01-01

    LISA Pathfinder (LPF), the precursor mission to a gravitational wave observatory of the European Space Agency, will measure the degree to which two test masses can be put into free fall, aiming to demonstrate a suppression of disturbance forces corresponding to a residual relative acceleration with a power spectral density (PSD) below (30 fm/sq s/Hz)(sup 2) around 1 mHz. In LPF data analysis, the disturbance forces are obtained as the difference between the acceleration data and a linear combination of other measured data series. In many circumstances, the coefficients for this linear combination are obtained by fitting these data series to the acceleration, and the disturbance forces appear then as the data series of the residuals of the fit. Thus the background noise or, more precisely, its PSD, whose knowledge is needed to build up the likelihood function in ordinary maximum likelihood fitting, is here unknown, and its estimate constitutes instead one of the goals of the fit. In this paper we present a fitting method that does not require the knowledge of the PSD of the background noise. The method is based on the analytical marginalization of the posterior parameter probability density with respect to the background noise PSD, and returns an estimate both for the fitting parameters and for the PSD. We show that both these estimates are unbiased, and that, when using averaged Welchs periodograms for the residuals, the estimate of the PSD is consistent, as its error tends to zero with the inverse square root of the number of averaged periodograms. Additionally, we find that the method is equivalent to some implementations of iteratively reweighted least-squares fitting. We have tested the method both on simulated data of known PSD and on data from several experiments performed with the LISA Pathfinder end-to-end mission simulator.

  17. State Teacher Evaluation and Teacher Education

    Science.gov (United States)

    Marchant, Gregory J.; David, Kristine A.; Rodgers, Deborah; German, Rachel L.

    2015-01-01

    Current accountability trends suggest an increasing role in state mandates regarding teacher evaluation. With various evaluation models and components serving as the basis for quality teaching, teacher education programs need to recognize the role teacher evaluation plays and incorporate aspects where appropriate. This article makes that case and…

  18. Towards a high quality high school workforce: A longitudinal, demographic analysis of U.S. public school physics teachers

    OpenAIRE

    Gregory T. Rushton; David Rosengrant; Andrew Dewar; Lisa Shah; Herman E. Ray; Keith Sheppard; Lynn Watanabe

    2017-01-01

    Efforts to improve the number and quality of the high school physics teaching workforce have taken several forms, including those sponsored by professional organizations. Using a series of large-scale teacher demographic data sets from the National Center for Education Statistics (NCES), this study sought to investigate trends in teacher quality at the national level in the two and a half decades between 1987 and 2012. Specifically, we investigated (i) details about the degree backgrounds, ma...

  19. Learning in DEPTH: Developing a Graphical Tool for Professional Thinking for Technology Teachers

    Science.gov (United States)

    Banks, Frank

    2008-01-01

    In this issue of the International Journal of Technology and Design, we report on a series of case studies from the second phase of an international project--Developing Professional Thinking for Technology Teachers (DEPTH2). The first phase of the project was a study conducted with both primary and secondary technology pre-service teacher…

  20. Strategies Applied by Teachers as Classroom Managers to Strengthen Learning

    Directory of Open Access Journals (Sweden)

    Franco Javier Jáuregui Contreras

    2017-05-01

    Full Text Available The present research was executed within the quantitative paradigm, under the feasible project modality, with the objective of designing strategies aimed at teachers to strengthen learning in the students of the Arnoldo Gabaldon educational unit, located in Delicias, Rafael Urdaneta municipality State Táchira. The methodology used responds to the characteristics of field descriptive research, not experimental. The study population consisted of 72 teachers. To obtain the information, a 20-item contentive instrument was applied, which measured the factors that influence the application of managerial strategies to strengthen student learning. This instrument was validated and a reliability index of 0.81 was obtained. In the analysis of results, the single and absolute frequencies of each reagent were determined. This resulted in a series of constantly occurring situations that led to the following conclusions: managerial strategies are employed by teachers on average, as well as in organization and planning, there is no commitment in relation to it, although there It was possible to detect that teachers comply with the planned activities on a regular basis. In addition, in the case of management and control, it is denoted how forcefully both processes are fulfilled, even in the majority, and both are assumed as managerial strategies. Therefore, the implementation of strategies is recommended.

  1. Semi-parametric estimation for ARCH models

    Directory of Open Access Journals (Sweden)

    Raed Alzghool

    2018-03-01

    Full Text Available In this paper, we conduct semi-parametric estimation for autoregressive conditional heteroscedasticity (ARCH model with Quasi likelihood (QL and Asymptotic Quasi-likelihood (AQL estimation methods. The QL approach relaxes the distributional assumptions of ARCH processes. The AQL technique is obtained from the QL method when the process conditional variance is unknown. We present an application of the methods to a daily exchange rate series. Keywords: ARCH model, Quasi likelihood (QL, Asymptotic Quasi-likelihood (AQL, Martingale difference, Kernel estimator

  2. An empirical method for approximating stream baseflow time series using groundwater table fluctuations

    Science.gov (United States)

    Meshgi, Ali; Schmitter, Petra; Babovic, Vladan; Chui, Ting Fong May

    2014-11-01

    Developing reliable methods to estimate stream baseflow has been a subject of interest due to its importance in catchment response and sustainable watershed management. However, to date, in the absence of complex numerical models, baseflow is most commonly estimated using statistically derived empirical approaches that do not directly incorporate physically-meaningful information. On the other hand, Artificial Intelligence (AI) tools such as Genetic Programming (GP) offer unique capabilities to reduce the complexities of hydrological systems without losing relevant physical information. This study presents a simple-to-use empirical equation to estimate baseflow time series using GP so that minimal data is required and physical information is preserved. A groundwater numerical model was first adopted to simulate baseflow for a small semi-urban catchment (0.043 km2) located in Singapore. GP was then used to derive an empirical equation relating baseflow time series to time series of groundwater table fluctuations, which are relatively easily measured and are physically related to baseflow generation. The equation was then generalized for approximating baseflow in other catchments and validated for a larger vegetation-dominated basin located in the US (24 km2). Overall, this study used GP to propose a simple-to-use equation to predict baseflow time series based on only three parameters: minimum daily baseflow of the entire period, area of the catchment and groundwater table fluctuations. It serves as an alternative approach for baseflow estimation in un-gauged systems when only groundwater table and soil information is available, and is thus complementary to other methods that require discharge measurements.

  3. Teacher-Child Relationships: Contribution of Teacher and Child Characteristics

    Science.gov (United States)

    Choi, Ji Young; Dobbs-Oates, Jennifer

    2016-01-01

    This study investigates potential predictors of teacher-child relationships (i.e., closeness and conflict) focusing on child gender, teacher-child ethnicity match, and teacher education. Additionally, the study explores the possible moderation effect of teacher education on the associations between teacher-child relationships and child gender or…

  4. Web-Enhanced Instruction and Learning: Findings of a Short- and Long-Term Impact Study and Teacher Use of NASA Web Resources

    Science.gov (United States)

    McCarthy, Marianne C.; Grabowski, Barbara L.; Koszalka, Tiffany

    2003-01-01

    Over a three-year period, researchers and educators from the Pennsylvania State University (PSU), University Park, Pennsylvania, and the NASA Dryden Flight Research Center (DFRC), Edwards, California, worked together to analyze, develop, implement and evaluate materials and tools that enable teachers to use NASA Web resources effectively for teaching science, mathematics, technology and geography. Two conference publications and one technical paper have already been published as part of this educational research series on Web-based instruction and learning. This technical paper, Web-Enhanced Instruction and Learning: Findings of a Short- and Long-Term Impact Study, is the culminating report in this educational research series and is based on the final report submitted to NASA. This report describes the broad spectrum of data gathered from teachers about their experiences using NASA Web resources in the classroom. It also describes participating teachers responses and feedback about the use of the NASA Web-Enhanced Learning Environment Strategies reflection tool on their teaching practices. The reflection tool was designed to help teachers merge the vast array of NASA resources with the best teaching methods, taking into consideration grade levels, subject areas and teaching preferences. The teachers described their attitudes toward technology and innovation in the classroom and their experiences and perceptions as they attempted to integrate Web resources into science, mathematics, technology and geography instruction.

  5. Stories we live, identities we build: how are elementary teachers' science identities shaped by their lived experiences?

    Science.gov (United States)

    Avraamidou, Lucy

    2018-02-01

    The aim of this multiple case study was to uncover a series of critical events and experiences related to the formation of the science identities of four beginning elementary female teachers, through a life-history approach and a conceptualization of teacher identity as lived experience. Grounded within the theoretical framework of Figured Worlds, the study used qualitative, interpretive methods for data collection (interviews, biographies, teaching philosophies) and analysis. The analysis shed light on the ways in which various experiences situated within different Figured Worlds (science, family and childhood, schooling, out-of-school, university, professional) impacted the participants' identity trajectories. The findings provided three main insights that contribute to science identity research and have implications for elementary teacher preparation: (a) science teacher identity is multidimensional and extends beyond cognitive domains of becoming to include affective dimensions; (b) science teacher identity is relational, linked and shaped by various other constructs or sub-identities; (c) place and time, defined as a space with meaning created by experiences, and science teacher identity are inextricably bound to one another.

  6. GLACIER VOLUME CHANGE ESTIMATION USING TIME SERIES OF IMPROVED ASTER DEMS

    Directory of Open Access Journals (Sweden)

    L. Girod

    2016-06-01

    Full Text Available Volume change data is critical to the understanding of glacier response to climate change. The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER system embarked on the Terra (EOS AM-1 satellite has been a unique source of systematic stereoscopic images covering the whole globe at 15m resolution and at a consistent quality for over 15 years. While satellite stereo sensors with significantly improved radiometric and spatial resolution are available to date, the potential of ASTER data lies in its long consistent time series that is unrivaled, though not fully exploited for change analysis due to lack of data accuracy and precision. Here, we developed an improved method for ASTER DEM generation and implemented it in the open source photogrammetric library and software suite MicMac. The method relies on the computation of a rational polynomial coefficients (RPC model and the detection and correction of cross-track sensor jitter in order to compute DEMs. ASTER data are strongly affected by attitude jitter, mainly of approximately 4 km and 30 km wavelength, and improving the generation of ASTER DEMs requires removal of this effect. Our sensor modeling does not require ground control points and allows thus potentially for the automatic processing of large data volumes. As a proof of concept, we chose a set of glaciers with reference DEMs available to assess the quality of our measurements. We use time series of ASTER scenes from which we extracted DEMs with a ground sampling distance of 15m. Our method directly measures and accounts for the cross-track component of jitter so that the resulting DEMs are not contaminated by this process. Since the along-track component of jitter has the same direction as the stereo parallaxes, the two cannot be separated and the elevations extracted are thus contaminated by along-track jitter. Initial tests reveal no clear relation between the cross-track and along-track components so that the latter

  7. Adaptive Anchoring Model: How Static and Dynamic Presentations of Time Series Influence Judgments and Predictions.

    Science.gov (United States)

    Kusev, Petko; van Schaik, Paul; Tsaneva-Atanasova, Krasimira; Juliusson, Asgeir; Chater, Nick

    2018-01-01

    When attempting to predict future events, people commonly rely on historical data. One psychological characteristic of judgmental forecasting of time series, established by research, is that when people make forecasts from series, they tend to underestimate future values for upward trends and overestimate them for downward ones, so-called trend-damping (modeled by anchoring on, and insufficient adjustment from, the average of recent time series values). Events in a time series can be experienced sequentially (dynamic mode), or they can also be retrospectively viewed simultaneously (static mode), not experienced individually in real time. In one experiment, we studied the influence of presentation mode (dynamic and static) on two sorts of judgment: (a) predictions of the next event (forecast) and (b) estimation of the average value of all the events in the presented series (average estimation). Participants' responses in dynamic mode were anchored on more recent events than in static mode for all types of judgment but with different consequences; hence, dynamic presentation improved prediction accuracy, but not estimation. These results are not anticipated by existing theoretical accounts; we develop and present an agent-based model-the adaptive anchoring model (ADAM)-to account for the difference between processing sequences of dynamically and statically presented stimuli (visually presented data). ADAM captures how variation in presentation mode produces variation in responses (and the accuracy of these responses) in both forecasting and judgment tasks. ADAM's model predictions for the forecasting and judgment tasks fit better with the response data than a linear-regression time series model. Moreover, ADAM outperformed autoregressive-integrated-moving-average (ARIMA) and exponential-smoothing models, while neither of these models accounts for people's responses on the average estimation task. Copyright © 2017 The Authors. Cognitive Science published by Wiley

  8. Viva La Diferencia! Segundo Modulo de una Serie para Maestros de Escuela Elemental (Long Live the Difference! Second Module of a Series for Elementary School Teachers).

    Science.gov (United States)

    Molina, Carmen Eneida, Ed.; And Others

    This guide, in English and Spanish, is designed to provide teachers with a scientific basis for identifying myths and distortions about men and women. A pre-test and post-test are included to measure the user's awareness of stereotypes. Object lessons address the following areas: (1) common sexual stereotypes; (2) sexual functions; (3) the…

  9. Examining the Effect of External Factors and Context-Dependent Beliefs of Teachers in the Use of ICT in Teaching: Using an Elaborated Theory of Planned Behavior

    Science.gov (United States)

    Salleh, Sallimah; Laxman, Kumar

    2015-01-01

    Research into teachers' attitudes, beliefs, competence, and inhibitions in relation to their use of technology may provide answers to a series of questions from administrators that relate to teachers' classroom implementation of Information and Communication Technology. The theory of planned behavior is a useful model for providing a framework for…

  10. Classical pooling of cross-section and time series data

    International Nuclear Information System (INIS)

    Nuamah, N.N.N.N.

    2000-04-01

    This paper discusses the classical pooling of cross-section and time series data. The re-expressions of the normal equations of this model are given to indicate the source of the paradox that arises in the estimation of the regression coefficient. (author)

  11. Weighted statistical parameters for irregularly sampled time series

    Science.gov (United States)

    Rimoldini, Lorenzo

    2014-01-01

    Unevenly spaced time series are common in astronomy because of the day-night cycle, weather conditions, dependence on the source position in the sky, allocated telescope time and corrupt measurements, for example, or inherent to the scanning law of satellites like Hipparcos and the forthcoming Gaia. Irregular sampling often causes clumps of measurements and gaps with no data which can severely disrupt the values of estimators. This paper aims at improving the accuracy of common statistical parameters when linear interpolation (in time or phase) can be considered an acceptable approximation of a deterministic signal. A pragmatic solution is formulated in terms of a simple weighting scheme, adapting to the sampling density and noise level, applicable to large data volumes at minimal computational cost. Tests on time series from the Hipparcos periodic catalogue led to significant improvements in the overall accuracy and precision of the estimators with respect to the unweighted counterparts and those weighted by inverse-squared uncertainties. Automated classification procedures employing statistical parameters weighted by the suggested scheme confirmed the benefits of the improved input attributes. The classification of eclipsing binaries, Mira, RR Lyrae, Delta Cephei and Alpha2 Canum Venaticorum stars employing exclusively weighted descriptive statistics achieved an overall accuracy of 92 per cent, about 6 per cent higher than with unweighted estimators.

  12. CLIL Teacher Professional Development for Content Teachers in Thailand

    Directory of Open Access Journals (Sweden)

    Punwalai Kewara

    2018-01-01

    Full Text Available In Thailand, the new educational policy is mandated to encourage content teachers to integrate English in content classrooms. The policy has created tensions and misconceptions among content teachers, who must change the medium of instruction from Thai to English. This paper presents an attempt to foster teacher knowledge about the Content and Language Integrated Learning (CLIL approach in a teacher professional development program. Classroom language in English and CLIL classroom structure were provided for 15 teachers at a secondary school. Four volunteer teachers were observed to determine the extent to which teachers implemented CLIL. The findings revealed the teachers partly implemented classroom language in English and the provided CLIL structure was not evident. The contribution of this paper is to the literature of CLIL teacher professional development effectiveness and the implementation fidelity of a professional development program.

  13. Tecnologia educativa: Lengua nacional 4. Guiones didacticos para el profesor (Educational Technology: National Language 4. Teacher's Guide).

    Science.gov (United States)

    Peniche Leger, Maria Elena

    This is the fourth in a series of six teacher's guides designed to accompany the Senda textbooks (FL 004 047 through 004 052). It contains instructions for presenting the lessons and for handling the individual needs of the pupils. (Author/SK)

  14. Tecnologia educativa: Lengua nacional 1. Guiones didacticos para el profesor (Educational Technology: National Language 1. Teacher's Guide).

    Science.gov (United States)

    Peniche Leger, Maria Elena

    This is the first in a series of six teacher's guides designed to accompany the Senda textbooks (FL 004 047 through 004 052). It contains instructions for presenting the lessons and for handling the individual needs of the pupils. (Author/SK)

  15. Tecnologia educativa: Lengua nacional 5. Guiones didacticos para el profesor (Educational Technology: National Language 5. Teacher's Guide).

    Science.gov (United States)

    Peniche Leger, Maria Elena

    This is the fifth in a series of six teacher's guides designed to accompany the Senda textbooks (FL 004 047 through 004 052). It contains instructions for presenting the lessons and for handling the individual needs of the pupils. (Author/SK)

  16. Tecnologia educativa: Lengua nacional 6. Guiones didacticos para el profesor (Educational Technology: National Language 6. Teacher's Guide).

    Science.gov (United States)

    Peniche Leger, Maria Elena

    This is the sixth in a series of six teacher's guides designed to accompany the Senda textbooks (FL 004 047 through 004 052). It contains instructions for presenting the lessons and for handling the individual needs of the pupils. (Author/SK)

  17. Tecnologia educativa: Lengua nacional 2. Guiones didacticos para el profesor (Educational Technology: National Language 2. Teacher's Guide).

    Science.gov (United States)

    Peniche Leger, Maria Elena

    This is the second in a series of six teacher's guides designed to accompany the Senda textbooks (FL 004 047 through 004 052). It contains instructions for presenting the lessons and for handling the individual needs of the pupils. (Author/SK)

  18. Teachers' and Students' Perceptions of Effective Physics Teacher Characteristics

    Science.gov (United States)

    Korur, Fikret; Eryilmaz, Ali

    2012-01-01

    Problem Statement: What do teachers and students in Turkey perceive as the common characteristics of effective physics teachers? Purpose of Study: The first aim was to investigate the common characteristics of effective physics teachers by asking students and teachers about the effects of teacher characteristics on student physics achievement and…

  19. Fractal analysis and nonlinear forecasting of indoor 222Rn time series

    International Nuclear Information System (INIS)

    Pausch, G.; Bossew, P.; Hofmann, W.; Steger, F.

    1998-01-01

    Fractal analyses of indoor 222 Rn time series were performed using different chaos theory based measurements such as time delay method, Hurst's rescaled range analysis, capacity (fractal) dimension, and Lyapunov exponent. For all time series we calculated only positive Lyapunov exponents which is a hint to chaos, while the Hurst exponents were well below 0.5, indicating antipersistent behaviour (past trends tend to reverse in the future). These time series were also analyzed with a nonlinear prediction method which allowed an estimation of the embedding dimensions with some restrictions, limiting the prediction to about three relative time steps. (orig.)

  20. For Teachers, by Teachers: An Exploration of Teacher-Generated Online Professional Development

    Science.gov (United States)

    Rodesiler, Luke

    2017-01-01

    Participatory online professional development opportunities created for teachers by teachers have emerged with the proliferation of social media. This article presents an investigation of a voluntary, participant-driven, 5-week online professional development offering in which two high school English teachers invited colleagues at a distance to…

  1. Enabling Teacher Effectiveness: Teachers' Perspectives on Instructional Management.

    Science.gov (United States)

    Pfeifer, R. Scott

    As part of a study of teacher effectiveness and job satisfaction, a research team interviewed 85 elementary and secondary classroom teachers in 5 school districts in the San Francisco (California) Bay Area to gather teachers' perspectives on administrative leadership. Teachers portrayed effective principals as creating environments around the…

  2. Teacher and parent experiences of parent-teacher conferences

    African Journals Online (AJOL)

    teachers are seldom trained to interact with parents, and both parents and teachers often find such encounters stressful and ineffective. This paper investigates parent and teacher perspectives on the parent-teacher conference through a qualitative inquiry. This is framed by the contributions of ecological theorists to home- ...

  3. Physics Teachers' Views on Their Initial Teacher Education

    Science.gov (United States)

    Buabeng, Isaac; Conner, Lindsey; Winter, David

    2016-01-01

    This paper explores New Zealand (NZ) physics teachers' and physics educators' views about Initial Teacher Education (ITE). Perspectives of physics teachers nationally indicated that in general, teachers considered themselves not well-prepared in some content areas including electronics, modern physics, and atomic and nuclear physics. This may be…

  4. Views on Values Education: From Teacher Candidates to Experienced Teachers

    Science.gov (United States)

    Iscan, Canay Demirhan

    2015-01-01

    This study aimed to identify the views of experienced class teachers and class teacher candidates on values education. It conducted standard open-ended interviews with experienced class teachers and teacher candidates. The study group comprised 9 experienced class teachers from different socio-economic levels and 9 teacher candidates with…

  5. Lessons from Hurricane Katrina: The Employment Effects of The Mass Dismissal of New Orleans Teachers

    Science.gov (United States)

    Lincove, Jane Arnold; Barrett, Nathan; Strunk, Katharine O.

    2018-01-01

    In the aftermath of Hurricane Katrina, the Orleans Parish school district fired over 4,000 public school teachers as the city underwent a transition to a market-based system of charter schools. Using administrative data, we examine whether and how these teachers returned to public school employment and teaching. We estimate that school reform and…

  6. Value Priorities of Teacher Candidates in the Education Faculty of Pamukkale University in Denizli, Turkey

    Science.gov (United States)

    Tanriogen, Zeynep Meral

    2016-01-01

    Problem Statement: Behavior is the visible conclusion of unseen values. More concretely, the teaching attitudes of teachers are affected by their values. The study of values is therefore fundamental to the study of teaching. If it is possible to understand the values of teachers, it is possible to estimate the teaching behaviors of teacher…

  7. Economic Analysis in Series-Distillation Desalination

    Directory of Open Access Journals (Sweden)

    Mirna Rahmah Lubis

    2010-06-01

    Full Text Available The ability to produce potable water economically is the primary purpose of seawater desalination research. Reverse osmosis (RO and multi-stage flash (MSF cost more than potable water produced from fresh water resources. Therefore, this research investigates a high-efficiency mechanical vapor-compression distillation system that employs an improved water flow arrangement. The incoming salt concentration was 0.15% salt for brackish water and 3.5% salt for seawater, whereas the outgoing salt concentration was 1.5% and 7%, respectively. Distillation was performed at 439 K and 722 kPa for both brackish water feed and seawater feed. Water costs of the various conditions were calculated for brackish water and seawater feeds using optimum conditions considered as 25 and 20 stages, respectively. For brackish water at a temperature difference of 0.96 K, the energy requirement is 2.0 kWh/m3. At this condition, the estimated water cost is $0.39/m3 achieved with 10,000,000 gal/day distillate, 30-year bond, 5% interest rate, and $0.05/kWh electricity. For seawater at a temperature difference of 0.44 K, the energy requirement is 3.97 kWh/m3 and the estimated water cost is $0.61/m3. Greater efficiency of the vapor compression system is achieved by connecting multiple evaporators in series, rather than the traditional parallel arrangement. The efficiency results from the gradual increase of salinity in each stage of the series arrangement in comparison to parallel. Calculations using various temperature differences between boiling brine and condensing steam show the series arrangement has the greatest improvement at lower temperature differences. Keywords: desalination, dropwise condensation, mechanical-vapor compression

  8. Technology in the Aid of Delivering Economic Content to Teachers: Virtual Economics v. 3

    Directory of Open Access Journals (Sweden)

    John R. Swinton

    2012-01-01

    Full Text Available We examine the impact on student achievement of a face-to-face teacher workshop that also provides economics instructors with access to an electronic library of instructional and reference material for their economics classroom—Virtual Economics v. 3 (VE3, offered by the Council for Economic Education. Based on evidence using student and teacher-level administrative data from the Georgia Department of Education and controlling for students’ prior achievement in mathematics, we find evidence that the VE3 workshop experience increases student achievement in high school economics. Our difference-in-differences estimates suggest that teacher participation in the VE3 workshop increases student achievement by 0.061 standard deviations on Georgia’s high stakes economics end-of-course test. Future research should seek estimating the effect of treatments in education such as the VE3 workshop using randomized controlled trials (RCT.

  9. Extracting the relevant delays in time series modelling

    DEFF Research Database (Denmark)

    Goutte, Cyril

    1997-01-01

    selection, and more precisely stepwise forward selection. The method is compared to other forward selection schemes, as well as to a nonparametric tests aimed at estimating the embedding dimension of time series. The final application extends these results to the efficient estimation of FIR filters on some......In this contribution, we suggest a convenient way to use generalisation error to extract the relevant delays from a time-varying process, i.e. the delays that lead to the best prediction performance. We design a generalisation-based algorithm that takes its inspiration from traditional variable...

  10. Science Teachers' Perceptions of the Relationship Between Game Play and Inquiry Learning

    Science.gov (United States)

    Mezei, Jessica M.

    The implementation of inquiry learning in American science classrooms remains a challenge. Teachers' perceptions of inquiry learning are predicated on their past educational experiences, which means outdated methods of learning may influence teachers' instructional approaches. In order to enhance their understanding and ultimately their implementation of inquiry learning, teachers need new and more relevant models. This study takes a preliminary step exploring the potential of game play as a valuable experience for science teachers. It has been proposed that game play and inquiry experiences can embody constructivist processes of learning, however there has been little work done with science teachers to systematically explore the relationship between the two. Game play may be an effective new model for teacher education and it is important to understand if and how teachers relate game playing experience and knowledge to inquiry. This study examined science teachers' game playing experiences and their perceptions of inquiry experiences and evaluated teacher's recognition of learning in both contexts. Data was collected through an online survey (N=246) and a series of follow-up interviews (N=29). Research questions guiding the study were: (1) What is the nature of the relationship between science teachers' game experience and their perceptions of inquiry? (2) How do teachers describe learning in and from game playing as compared with inquiry science learning? and (3) What is the range of similarities and differences teachers articulate between game play and inquiry experiences?. Results showed weak quantitative links between science teachers' game experiences and their perceptions of inquiry, but identified promising game variables such as belief in games as learning tools, game experiences, and playing a diverse set of games for future study. The qualitative data suggests that teachers made broad linkages in terms of parallels of both teaching and learning. Teachers

  11. Formative Assessment: Exploring Tunisian Cooperative Teachers Practices in Physical Education

    Directory of Open Access Journals (Sweden)

    Melki Hasan

    2017-10-01

    Full Text Available Purpose: This article is based on questions related to the formative assessment of preparatory trainee ship in the professional life of Physical Education teachers. In general, in the first training program, the traineeship represents an integral part of training. In this sense, the traineeship offers a vital opportunity for future teacher to gain practical experience in the real environment, given that formative evaluation is a process of collecting evidence from trainees by cooperative teachers to make decisions about their knowledge and skills, to guide their own instructional activities and to control their behavior. Accordingly, this study proposed to explore practices of Tunisians cooperative teachers in relation to the formative assessment. Material: To verify our proposed object, we conducted a research using a questionnaire distributed among 96 cooperative teachers in different educational institutions located in the region of the greater Tunis. During the school year 2015-2016, the questionnaire was the subject of a statistical analysis using frequencies and percentages. Results: The analysis of such data revealed a range of practices about formative estimation among cooperative teachers. In particular, each teacher acknowledged the value of guiding and encouraging student’s self-assessment. So that they could lead their students to assume a share of evaluative activity. Conclusion: Both theoretical and practical implications of these findings are discussed, and some recommendations are made for future practice.

  12. `Indoor` series vending machines; `Indoor` series jido hanbaiki

    Energy Technology Data Exchange (ETDEWEB)

    Gensui, T.; Kida, A. [Fuji Electric Co. Ltd., Tokyo (Japan); Okumura, H. [Fuji Denki Reiki Co. Ltd., Tokyo (Japan)

    1996-07-10

    This paper introduces three series of vending machines that were designed to match the interior of an office building. The three series are vending machines for cups, paper packs, cans, and tobacco. Among the three series, `Interior` series has a symmetric design that was coated in a grain pattern. The inside of the `Interior` series is coated by laser satin to ensure a sense of superior quality and a refined style. The push-button used for product selection is hot-stamped on the plastic surface to ensure the hair-line luster. `Interior Phase II` series has a bay window design with a sense of superior quality and lightness. The inside of the `Interior Phase II` series is coated by laser satin. `Interior 21` series is integrated with the wall except the sales operation panel. The upper and lower dress panels can be detached and attached. The door lock is a wire-type structure with high operativity. The operation block is coated by titanium color. The dimensions of three series are standardized. 6 figs., 1 tab.

  13. Different methods for analysing and imputation missing values in wind speed series; La problematica de la calidad de la informacion en series de velocidad del viento-metodologias de analisis y imputacion de datos faltantes

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, A. M.

    2004-07-01

    This study concerns about different methods for analysing and imputation missing values in wind speed series. The algorithm EM and a methodology derivated from the sequential hot deck have been utilized. Series with missing values imputed are compared with original and complete series, using several criteria, such the wind potential; and appears to exist a significant goodness of fit between the estimates and real values. (Author)

  14. On Improving Density Estimators which are not Bona Fide Functions

    OpenAIRE

    Gajek, Leslaw

    1986-01-01

    In order to improve the rate of decrease of the IMSE for nonparametric kernel density estimators with nonrandom bandwidth beyond $O(n^{-4/5})$ all current methods must relax the constraint that the density estimate be a bona fide function, that is, be nonnegative and integrate to one. In this paper we show how to achieve similar improvement without relaxing any of these constraints. The method can also be applied for orthogonal series, adaptive orthogonal series, spline, jackknife, and other ...

  15. Science Library of Test Items. Volume Eight. Mastery Testing Program. Series 3 & 4 Supplements to Introduction and Manual.

    Science.gov (United States)

    New South Wales Dept. of Education, Sydney (Australia).

    Continuing a series of short tests aimed at measuring student mastery of specific skills in the natural sciences, this supplementary volume includes teachers' notes, a users' guide and inspection copies of test items 27 to 50. Answer keys and test scoring statistics are provided. The items are designed for grades 7 through 10, and a list of the…

  16. Quantifying complexity of financial short-term time series by composite multiscale entropy measure

    Science.gov (United States)

    Niu, Hongli; Wang, Jun

    2015-05-01

    It is significant to study the complexity of financial time series since the financial market is a complex evolved dynamic system. Multiscale entropy is a prevailing method used to quantify the complexity of a time series. Due to its less reliability of entropy estimation for short-term time series at large time scales, a modification method, the composite multiscale entropy, is applied to the financial market. To qualify its effectiveness, its applications in the synthetic white noise and 1 / f noise with different data lengths are reproduced first in the present paper. Then it is introduced for the first time to make a reliability test with two Chinese stock indices. After conducting on short-time return series, the CMSE method shows the advantages in reducing deviations of entropy estimation and demonstrates more stable and reliable results when compared with the conventional MSE algorithm. Finally, the composite multiscale entropy of six important stock indices from the world financial markets is investigated, and some useful and interesting empirical results are obtained.

  17. Advances in Antithetic Time Series Analysis : Separating Fact from Artifact

    Directory of Open Access Journals (Sweden)

    Dennis Ridley

    2016-01-01

    Full Text Available The problem of biased time series mathematical model parameter estimates is well known to be insurmountable. When used to predict future values by extrapolation, even a de minimis bias will eventually grow into a large bias, with misleading results. This paper elucidates how combining antithetic time series' solves this baffling problem of bias in the fitted and forecast values by dynamic bias cancellation. Instead of growing to infinity, the average error can converge to a constant. (original abstract

  18. Teacher Effectiveness of Secondary School Teachers with High Tacit Knowledge

    Science.gov (United States)

    Mumthas, N. S.; Blessytha, Anwar

    2009-01-01

    To be a great teacher, more than content knowledge, teacher also needs practical and technical knowledge that contribute to teacher effectiveness. A teacher with high tacit knowledge is usually considered an expert teacher. The purpose of this study is to find out whether teachers with high tacit knowledge give equal preference to the various…

  19. Possible Challenges of Teacher Research for Teacher Professional Development

    Directory of Open Access Journals (Sweden)

    Utami Widiati

    2016-02-01

    Full Text Available Teacher research (i.e. action research has gained acceptance as a tool for teacher professional development. In spite of its increasing popularity in language classrooms, concerns have been raised in the implementation of teacher research, such as issues of quality, sustainability, the development of standards, and accessibility. In the Indonesian context, the unprofessional working conditions and the education background of most teachers have made it difficult for teachers to sustain and access research. Since changing the former appears beyond the aim of this article, it is suggested that teacher education institutions focus on the latter, revisiting the curriculum of teacher education to provide more research components

  20. Teacher Inequality

    Directory of Open Access Journals (Sweden)

    Andrew J. Wayne

    2002-06-01

    Full Text Available When discussing the teacher quality gap, policy makers have tended to focus on teacher certification, degrees, and experience. These indicators have become key benchmarks for progress toward equality of educational opportunity, in part for lack of additional teacher quality indicators. This article turns attention to teachers' academic skills. National data on teachers' entrance examination scores and college selectivity reveal substantial disparities by school poverty level. The findings commend attention to the gap in academic skills in the formulation of future policy and research on the teacher quality gap.