This study looked at the effect of a number of factors such as the choice of analytical method, the handling method for missing data, sample size, and proportion of missing data, in order to evaluate the effect of missing data treatment on accuracy of estimation. In order to accomplish this a methodological approach involving simulated data was…

In multilevel modeling, group-level variables (L2) for assessing contextual effects are frequently generated by aggregating variables from a lower level (L1). A major problem of contextual analyses in the social sciences is that there is no error-free measurement of constructs. In the present article, 2 types of error occurring in multilevel data…

High quality assessment practice is expected to yield valid and useful score-based interpretations about what the examinees know and are able to do with respect to a defined target domain. Given this assertion, the article presents a framework based on the "unified view of validity," advanced by Cronbach and Messick over two decades ago, to assist…

Numerous studies have shown increasing item reliabilities as an effect of the item position in personality scales. Traditionally, these context effects are analyzed based on item-total correlations. This approach neglects that trends in item reliabilities can be caused either by an increase in true score variance or by a decrease in error…

Context effects are defined as being influences on test performance associated with the content of successively presented test items or sections. Four types of context effects are identified: (1) direct context effects (practice effects) which occur when performance on items is affected by the examinee having been exposed to similar types of…

Item parameter estimates vary for a variety of reasons, including estimation error, characteristics of the examinee samples, and context effects (e.g., item location effects, section location effects, etc.). Although we expect variation based on theory, there is reason to believe that observed variation in item parameter estimates exceeds what…