Two procedures are presented for detecting violations of the unidimensionality assumption made by latent trait models without requiring factor analysis of inter-item correlation matrices. Both procedures require that departures from unidimensionality be hypothesized beforehand. This is usually possible in achievement tests where several content…

Derivation of asymptotic variance-covariance matrices for item and personal parameters in item response models is demonstrated for one- and two-parameter models using maximum likelihood estimation. The results can be used in incomplete designs and in estimation of the accuracy of various designs beforehand. (TJH)

This report documents the development of a scale to measure hearing adults' beliefs about the capabilities of deaf adults. Test items from a list of misconceptions about deaf people were piloted with groups of 38 and 290 undergraduates. Analysis supports scale reliability and validity. (SLD)

A Monte Carlo investigation of simplex fitting as a method of determining the dimensionality of binary data matrices was conducted. Examination of the fit of correlation matrices with a known factor structure to correlation matrices that represent the perfect simplex shows that simplex fitting is a feasible approach under some circumstances. (SLD)

Computer simulations were run to measure the relationship between testlet validity and factors of item pool size and testlet length for both adaptive and linearly constructed testlets. Making a testlet adaptive yields only modest increases in aggregate validity because of the peakedness of the typical proficiency distribution. (Author/SLD)

A popular design in large-scale educational assessments as well as any other type of survey is the balanced incomplete block design. The design is based on an item pool split into a set of blocks of items that are assigned to sets of "assessment booklets." This article shows how the problem of calculating an optimal balanced incomplete block…

Twenty contemporary fears (e.g., terrorist attacks, drive-by shootings, having to fight in a war) were added to E. Gullone and N. J. King's (1992) Australian Fear Survey Schedule for Children-II for use in the United States. The revised survey, the American Fear Survey Schedule for Children (J. J. Burnham, 1995), was investigated. The component…

The construction of parallel editions of conventional tests for purposes of test security while maintaining score comparability has always been a recognized and difficult problem in psychometrics and test construction. The introduction of new modes of test construction, e.g., adaptive testing, changes the nature of the problem, but does not make…

A 1992 study by R. Gershon found discrepancies when comparing the theoretical Rasch item characteristic curve with the average empirical curve for 1,304 vocabulary items administered to 7,711 students. When person-item mismatches were deleted (for any person-item interaction where the ability of the person was much higher or much lower than the…

One of the item types in the Listening Comprehension section of the Test of English as a Foreign Language (TOEFL) test is the dialogue. Because the dialogue item pool needs to have an appropriate balance of items at a range of difficulty levels, test developers have examined items at various difficulty levels in an attempt to identify their…

The purpose of this study was to compare the scores of students who were allowed unlimited retakes of a multiple-choice test with the scores of students who were limited to only four retakes (five trials) of the same test. The tests were each made up of 20 randomly drawn questions from a large pool of questions about research methods. Three…

CSAR (Characteristic Storage And Retrieval) is the name of an interactive item bank system for the storage, retrieval, manipulation, and summarization of information about multiple choice test items. The purpose of the system is to facilitate the test construction process. The system has two main components: one or more item banks and an…

The Test Collection, Educational Testing Service, is an extensive library of over 14,000 tests and other measurement devices. The Test Collection acquires and disseminates information on hard-to-locate research instruments as well as on commercially available standardized tests. Drawn from the Test Collection's computer-retrievable database, this…

The most appropriate statistical model for the small-scale (n<100) studies common in language testing research is the Rasch one-parameter logistic model. The Rasch model provides a wide range of options for conducting research, refining existing examinations, and developing tailored (computerized adaptive) language tests. Three investigations…

The successful Wisconsin Title 1 project item bank offers a valid, flexible, and efficient means of providing migrant student tests in reading and mathematics tailored to instructor curricula. The item bank system consists of nine PASCAL computer programs which maintain, search, and select from approximately 1,000 test items stored on floppy disks…