Estimates a college-attendance equation for a common set of students (from the High School and Beyond Survey) using three popular econometric specifications: the multinomial logit, the ordered probit, and the bivariate probit. Estimated marginal effects do not differ significantly across the three specifications. Choice of specification may not…

This paper discusses the limitations of Classical Test Theory, the purpose of Item Response Theory/Latent Trait Measurement models, and the step-by-step calculations in the Rasch measurement model. The paper explains how Item Response Theory (IRT) transforms person abilities and item difficulties into the same metric for test-independent and…

Ordinary least-squares regression treats the variables asymmetrically, designating a dependent variable and one or more independent variables. When it is not obvious how to make this distinction, a researcher may prefer to use orthogonal regression, which treats the variables symmetrically. However, the usual procedure for orthogonal regression is…

Bayesian methods for estimating dose response curves in quantal bioassay are studied. A linearized multi-stage model is assumed for the shape of the curves. A Gibbs sampling approach with data augmentation is employed to compute the Bayes estimates. In addition, estimation of the "relative additional risk" and the "risk specific…

This study developed a hybrid of item response theory (IRT) models and latent class models, which combined the strengths of each type of model. The primary motivation for developing the new model is to describe characteristics of examinees' knowledge at the time of the examination. Hence, the application of the model lies mainly in so-called…

In order to evaluate our methods and approaches of estimating the operating characteristics of discrete item responses, it is necessary to try other comparable methods on similar sets of data. LOGIST 5 was taken up for this reason, and was tried upon the hypothetical test items, which follow the normal ogive model and were used frequently in…

Simple sum procedure of the conditional PDF approach (plausiblity of distractor function) combined with the normal approach method was applied for estimating the plausibility functions of the distractors of the Level II vocabulary subtest items of the Iowa Tests of Basic Skills. In so doing, the normal ogive model was adopted for the correct…

Recent developments in dichotomous factor analysis based on multidimensional item response models (Bock and Aitkin, 1981; Muthen, 1978) provide an effective method for exploring the dimensionality of questionnaire items. Implemented in the TESTFACT program, this "full information" item factor analysis accounts not only for the pairwise…

The psychometric research done by G. Rasch between 1951 and 1959, which is explained and illustrated in this book, takes psychometrics from being purely descriptive to being a science of objective measurement. Individual centered statistics require models in which each individual is characterized separately and from which, given adequate data,…

The 1987-88 Schools and Staffing Survey (SASS) looked at a national sample of elementary and secondary public and private schools. Components of the SASS, a data collection effort of the National Center for Education Statistics, were surveys of teacher demand and shortage, schools, administrators, and teachers. Approximately 13,000 schools and…

The use of a three-parameter logistic model for applying latent trait theory has become more popular because of the availability of computer programs. The program Logist 5 can be used not only for the item parameter estimation in the three-parameter logistic model, but also in the two parameter logistic model by setting the third parameter equal…

Although policy makers have expressed interest in expenditures by private elementary and secondary schools, nationally representative data in this area are not available. In the absence of expenditure data it may nevertheless be possible to derive national estimates of total expenditures by private schools indirectly, by using the information that…

The feasibility of pre-equating, or establishing conversions from raw to scaled scores through the use of pretest data before operationally administering a test, was investigated for the Scholastic Aptitude Test (SAT). Item-response theory based equating methods were used to estimate item parameters on SAT pretest data, instead of using final form…

The stability of Rasch test item difficulty parameters was investigated under varying conditions. Data were taken from a mathematics achievement test administered to over 2,000 Australian students. The experiments included: (1) relative stability of the Rasch, traditional, and z-item difficulty parameters using different sample sizes and designs;…