This report outlines the development, methodology, and results of the split-half administration of the 2015 School Crime Supplement (SCS) to the National Crime Victimization Survey (NCVS). The National Crime Victimization Survey (NCVS) is sponsored by the U.S. Department of Justice, Bureau of Justice Statistics (BJS). The U.S. Census Bureau…

The purpose of this study was to apply a random item mixture nominal item response model (RIM-MixNRM) for investigating instruction effects. The host study design was a pre-test-and-post-test, school-based cluster randomized trial. A RIM-MixNRM was used to identify students' error patterns in mathematics at the pre-test and the post-test.…

Differential item functioning (DIF) indicates the violation of the invariance assumption, for instance, in models based on item response theory (IRT). For item-wise DIF analysis using IRT, a common metric for the item parameters of the groups that are to be compared (e.g., for the reference and the focal group) is necessary. In the Rasch model,…

An essential feature of the linear logistic test model (LLTM) is that item difficulties are explained using item design properties. By taking advantage of this explanatory aspect of the LLTM, in a mixture extension of the LLTM, the meaning of latent classes is specified by how item properties affect item difficulties within each class. To improve…

This study investigates the effect of proficiency- vs. performance-based elicited imitation (EI) assessment. EI requires test-takers to repeat sentences in the target language. The accuracy at which test-takers are able to repeat sentences highly correlates with test-takers' language proficiency. However, in EI, the factors that render an item…

Since its first pilot study was launched in 2003, China Accreditation Test for Translators and Interpreters (CATTI) has developed into the most authoritative translation and interpretation proficiency qualification accreditation test in China and played an important role in assessing and cultivating translators and interpreters. Based on the…

a-Stratified computerized adaptive testing with b-blocking (AST), as an alternative to the widely used maximum Fisher information (MFI) item selection method, can effectively balance item pool usage while providing accurate latent trait estimates in computerized adaptive testing (CAT). However, previous comparisons of these methods have treated…

The assumption of conditional independence between the responses and the response times (RTs) for a given person is common in RT modeling. However, when the speed of a test taker is not constant, this assumption will be violated. In this article we propose a conditional joint model for item responses and RTs, which incorporates a covariance…

The purpose of this study was to apply two types of Differential Item Functioning (DIF), net and global DIF, as well as the framework of Differential Step Functioning (DSF) to real testing data to investigate measurement invariance related to test language. Data from the Program for International Student Assessment (PISA)-2006 polytomously scored…

This study tests a hypothesized learning progression for the concept of energy. It looks at 14 specific ideas under the categories of (i) Energy Forms and Transformations; (ii) Energy Transfer; (iii) Energy Dissipation and Degradation; and (iv) Energy Conservation. It then examines students' growth of understanding within each of these ideas at…

We describe the construction, validation, and testing of a concept inventory for an "Introduction to Physics of Semiconductors" course offered by the department of physics to undergraduate engineering students. By design, this inventory addresses both content knowledge and the ability to interpret content via different cognitive…

Item discrimination index, which indicates the ability of the item to distinguish whether or not the individuals have acquired the qualities that are evaluated, is basically a validity measure and it is estimated by examining the fit between item score and the test score. Based on the definition of item discrimination index, classroom observation…

A problem faced by many instructors is that of designing exams that accurately assess the abilities of the students. Typically, these exams are prepared several days in advance, and generic question scores are used based on rough approximation of the question difficulty and length. For example, for a recent class taught by the author, there were…

Item positions in educational assessments are often randomized across students to prevent cheating. However, if altering item positions results in any significant impact on students' performance, it may threaten the validity of test scores. Two widely used approaches for detecting position effects -- logistic regression and hierarchical…

This study tests a hypothesized learning progression for the concept of energy. It looks at 14 specific ideas under the categories of (i) Energy Forms and Transformations; (ii) Energy Transfer; (iii) Energy Dissipation and Degradation; and (iv) Energy Conservation. It then examines students' growth of understanding within each of these ideas at…