From a decision theoretic viewpoint, a general coefficient (delta) for tests is derived. The coefficient is applied to three kinds of decision situations. The first situation involves a true score estimated by a function of the observed score of a subject on a test (point estimation). Using the squared error loss function and Kelley's formula for…

During the last decade the use of Bayesian statistical method has become quite prevalent in the educational community. Yet, like most statistical techniques, little has been written concerning the application of these methods to the classroom setting. The purpose of this paper is to help correct such a deficiency in the literature by developing a…

Biases in judgment reveal some heuristics of thinking about uncertainty. Three heuristics are discussed. (Author/RH)

Given reflection symmetry, the moment generating function symmetry is necessary and sufficient for the random walk model to be equivalent to a sequential probability ratio test. For a related article, see TM 501 715. (Author/RC)

This investigation examined the effects of a variety of cue criterion function forms and attempted to evaluate the contribution of the factors just named, i.e., the response consistency of subjects, detection of task linearity, and the detection of task nonlinearity, to observed differences in learning. (Author/RK)

Reported are the results of a study which investigated the influence of certain variables within the method of individually guided discovery in mathematics. The independent variables considered were the concepts of ordered partitions and permutations, the level of consolidation or practice after discovery, and the teachers. Also considered were…

Sensitivity data is defined as involving two response categories, with responses observed at different levels of some variable. The responses are taken to indicate sensitivity to the variable and may be labeled "positive" or "negative." The countback method offers confidence limits for the 50% point, the level of the variable…

The Fisher Exact Probability Test considers independent groups and dichotomous criterion in a 2 by 2 (fourfold) contingency table. Fisher's test requires a determination of the combined probability of the observed frequency distribution and of the more extreme (in the same direction) frequency distributions. Typically, Fisher's test is for a small…

The subject of this study is the process by which unemployed workers are reemployed after a layoff. A theoretical model of job search is formulated with asking price based on number of job vacancies, distribution of offers, value placed on nonmarket activity, cost of search activity, and interest rate. A probability model of reemployment is…

To resolve a recent controversy between Klein and Cleary and Levy, a model for dichotomous congeneric items is presented which has mean errors of zero, dichotomous true scores that are uncorrelated with errors, and errors that are mutually uncorrelated. (Author)

In this paper a reliable method is found for approximating the value of the Bivariate Normal Correlation Coefficient, rho, given values of the joint probability and the normal deviates, h and k, or the related areas. This technique finds useful application in the computation of the tetrachoric correlation coefficient, r, when the underlying…

The use of Bayesian statistics as the basis of classical analysis of data is described. Bayesian analysis is a set of procedures for changing opinions about a given phenomenon based upon rational observation of a set of data. The Bayesian arrives at a set of prior beliefs regarding some states of nature; he observes data in a study and then…

In this paper, a new item analysis index, e, is derived as a function of difficulty and discrimination to represent item efficiency. Item discrimination in this paper is not independent of item difficulty, and it is demonstrated algebraically that the maximum discriminating power of an item may be determined from its difficulty. Item efficiency is…

Bayesian statistical inference is unfamiliar to many educational evaluators. While the classical model is useful in educational research, it is not as useful in evaluation because of the need to identify solutions to practical problems based on a wide spectrum of information. The reason Bayesian analysis is effective for decision making is that it…