This paper describes the graded response model. The graded response model represents a family of mathematical models that deal with ordered polytomous categories, such as: (1) letter grading; (2) an attitude survey with "strongly disagree, disagree, agree, and strongly agree" choices; (3) partial credit given in accord with an…

A new model, the acceleration model, is proposed in the framework of the heterogeneous case of the graded response model, based on processing functions defined for a finite or enumerable number of steps. The model is expected to be useful in cognitive assessment. (SLD)

The logistic positive exponent family (LPEF) of models has been proposed by F. Samejima (1998) for dichotomous responses. This family of models is characterized by point-asymmetric item characteristic curves (ICCs). This paper introduces the LPEF family, and discusses its usefulness in educational measurement and the implications of its use.…

F. Samejima's approximation for the bias function for the maximum likelihood estimate of the latent trait in the general case where item responses are discrete is explored. Observations are made about the behavior of this bias function for the dichotomous response level in general. Empirical examples are given. (SLD)

An approximation for the bias function of the maximum likelihood estimate of the latent trait or ability is developed for the general case where item responses are discrete, which includes the dichotomous response level, the graded response level, and the nominal response level. (SLD)

Test validity is a concept that has often been ignored in the context of latent trait models and in modern test theory, particularly as it relates to computerized adaptive testing. Some considerations about the validity of a test and of a single item are proposed. This paper focuses on measures that are population-free and that will provide local…

A method is proposed that increases the accuracies of estimation of the operating characteristics of discrete item responses, especially when the true operating characteristic is represented by a steep curve, and also at the lower and upper ends of the ability distribution where the estimation tends to be inaccurate because of the smaller number…

Because the test information function and its two modified formulas provide useful information, the reliability coefficient of a test is no longer necessary in modern mental test theory. Yet it is interesting to know how to predict the coefficient using the test information function and its modifications, tailored for each separate population of…

Two modification formulas are presented for the test information function in order to provide better measures of local accuracies of the estimation of "theta" when maximum likelihood estimation is used to provide the estimate of ability "theta." A minimum bound of any estimator, biased or unbiased, is considered; and Formula 1…

This paper is the final report of a multi-year project sponsored by the Office of Naval Research (ONR) in 1987 through 1990. The main objectives of the research summarized were to: investigate the non-parametric approach to the estimation of the operating characteristics of discrete item responses; revise and strengthen the package computer…

The shortcomings of the conventional way of using and interpreting multiple-choice tests are summarized. Some theories and methodologies that can be applied for better use multiple-choice test items are described. Empirical facts are introduced to support the theoretical observations. New strategies are proposed that will reduce "noise"…