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Sandip Sinharay 《Educational Measurement》2021,40(1):79-91
Technical difficulties occasionally lead to missing item scores and hence to incomplete data on computerized tests. It is not straightforward to report scores to the examinees whose data are incomplete due to technical difficulties. Such reporting essentially involves imputation of missing scores. In this paper, a simulation study based on data from three educational tests is used to compare the performances of six approaches for imputation of missing scores. One of the approaches, based on data mining, is the first application of its kind to the problem of imputation of missing data. The approach based on data mining and a multiple imputation approach based on chained equations led to the most accurate imputation of missing scores, and hence to most accurate score reporting. A simple approach based on linear regression performed the next best overall. Several recommendations are made regarding the reporting of scores to examinees with incomplete data. 相似文献
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Biswajit Majumdar Susri Ray Chaudhuri Arun Ray Sandip K Bandyopadhyay 《Indian journal of clinical biochemistry : IJCB》2002,17(1):49-57
Pretreatment of an ethanolic extract of leaf ofPiper betle linn at a dose of 200mg/kg body weight, orally administered to rats for ten consecutive days, was found to possess a significant
protective action against gastric lesions induced by indomethacin. The extract pretreatment resulted in significant increase
in superoxide dismutase (SOD) and catalase (CAT) activity, increase in mucus, hexosamine and total thiol group content, but
marked reduction in oxidatively damaged protein and peroxidised lipid levels as compared to untreated ulcerated control. The
extract was also found to possess both superoxide and hydroxyl free radical scavenging action. The present observations establish
the efficacy of the extract in prevention of experimentally induced peptic ulcer by indomethacin and antioxidant property
appears to be predominantly responsible for such cytoprotective activity in the experimental model. 相似文献
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Sandip Sinharay 《Educational Measurement》2016,35(3):38-54
Data mining methods for classification and regression are becoming increasingly popular in various scientific fields. However, these methods have not been explored much in educational measurement. This module first provides a review, which should be accessible to a wide audience in education measurement, of some of these methods. The module then demonstrates using three real‐data examples that these methods may lead to an improvement over traditionally used methods such as linear and logistic regression in educational measurement. 相似文献
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Motivated by the wide application of Markov-chain steady-state-probability estimation, we pursue a spectral and graph-theoretic performance analysis of a classical estimator for steady-state probabilities here. Specifically, we connect a performance measure to estimate the structure of the underlying graph defined on the Markov-chain's state transitions. To do so, (1) we present a series of upper bounds on the performance measure in terms of the subdominant eigenvalue of the state transition matrix, which is closely connected with the graph structure; (2) as an illustration of the graph-theoretic analysis, we then relate the subdominant eigenvalue to the connectivity of the graph, including for the strong-connectivity case and the weak-link case. We also apply the results to characterize estimation in Markov chains with rewards. 相似文献
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The nonequivalent groups with anchor test (NEAT) design involves missing data that are missing by design. Three equating methods that can be used with a NEAT design are the frequency estimation equipercentile equating method, the chain equipercentile equating method, and the item-response-theory observed-score-equating method. We suggest an approach to perform a fair comparison of the three methods. The approach is then applied to compare the three equating methods using three data sets from operational tests. For each data set, we examine how the three equating methods perform when the missing data satisfy the assumptions made by only one of these equating methods. The chain equipercentile equating method is somewhat more satisfactory overall than the other methods. 相似文献
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There is an increasing interest in reporting subscores, both at examinee level and at aggregate levels. However, it is important to ensure reasonable subscore performance in terms of high reliability and validity to minimize incorrect instructional and remediation decisions. This article employs a statistical measure based on classical test theory that is conceptually similar to the test reliability measure and can be used to determine when subscores have any added value over total scores. The usefulness of subscores is examined both at the level of the examinees and at the level of the institutions that the examinees belong to. The suggested approach is applied to two data sets from a basic skills test. The results provide little support in favor of reporting subscores for either examinees or institutions for the tests studied here. 相似文献
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Dodeen (2004) studied the correlation between the item parameters of the three-parameter logistic model and two item fit statistics, and found some linear relationships (e.g., a positive correlation between item discrimination parameters and item fit statistics) that have the potential for influencing the work of practitioners who employ item response theory. This article examines the same type of linear relationships as studied by Dodeen. However, this article adds to the literature by employing item fit statistics not considered by Dodeen, which have been recently suggested and whose Type I error rates have been demonstrated to be generally close to the nominal level. Detailed simulations show that if one uses certain of the recently suggested item fit statistics, there is no need to worry about any linear relationships between the item parameters and item fit statistics. 相似文献
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A New Interpretation of Augmented Subscores and Their Added Value in Terms of Parallel Forms 
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下载免费PDF全文 Sandip Sinharay 《Journal of Educational Measurement》2018,55(2):177-193
The value‐added method of Haberman is arguably one of the most popular methods to evaluate the quality of subscores. The method is based on the classical test theory and deems a subscore to be of added value if the subscore predicts the corresponding true subscore better than does the total score. Sinharay provided an interpretation of the added value of subscores in terms of scores and subscores on parallel forms. This article extends the results of Sinharay and considers the prediction of a subscore on a parallel form from both the subscore and the total raw score on the original form. The resulting predictor essentially becomes the augmented subscore suggested by Haberman. The proportional reduction in mean squared error of the resulting predictor is interpreted as a squared multiple correlation coefficient. The practical usefulness of the derived results is demonstrated using an operational data set. 相似文献
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Assessing Fit of Unidimensional Item Response Theory Models Using a Bayesian Approach 总被引：1，自引：0，他引：1
Sandip Sinharay 《Journal of Educational Measurement》2005,42(4):375-394
Even though Bayesian estimation has recently become quite popular in item response theory (IRT), there is a lack of works on model checking from a Bayesian perspective. This paper applies the posterior predictive model checking (PPMC) method ( Guttman, 1967 ; Rubin, 1984 ), a popular Bayesian model checking tool, to a number of real applications of unidimensional IRT models. The applications demonstrate how to exploit the flexibility of the posterior predictive checks to meet the need of the researcher. This paper also examines practical consequences of misfit, an area often ignored in educational measurement literature while assessing model fit. 相似文献