Cox (1972) proposed a discrete-time survival model that is somewhat analogous to the proportional hazards model for continuous time. Efron (1988) showed that this model can be estimated using ordinary logistic regression software, and Singer and Willett (1993) provided a detailed illustration of a particularly flexible form of the model that…

The current study attempts to differentiate effects of phonotactic probability (i.e. the likelihood of occurrence of a sound sequence), neighbourhood density (i.e. the number of phonologically similar words), word frequency, and word length on expressive vocabulary development by young children. Naturalistic conversational samples for three…

Six methods for smoothing double-entry expectancy tables (tables that relate two predictor variables to probability of attaining a selected level of success on a criterion) were compared using data for entering students at 85 colleges and universities. ACT composite scores and self-reported high school grade averages were used to construct…

A mathematical model for computer-aided instruction has been developed. The assumption is made that the course is divided into a hierarchy of levels of difficulty and that if a student is able to perform successfully at a given level of difficulty, he can also perform successfully at all levels of lesser difficulty. Furthermore, if a student…

An analytical framework is described through which voluntary attrition can be predicted. The approach incorporates Marshallian Utility Theory and a Maximum Likelihood Estimation procedure to evaluate a specific individual's propensity to attrit. The approach was tested twice at the United States Air Force Academy where it was able to correctly…

Debates about developmental instruction have prompted postsecondary institutions to justify their developmental courses. This study investigated a method of documenting the benefits of developmental courses that involves using placement test scores to predict college outcomes separately for students who take a developmental course before taking…

A communicativity index (Index I) is described that measures the potential communication function performed by a given language in a designated communication situation. Significant sociolinguistic contrasts between the language situations of West Malaysia and Singapore are revealed by applying this index. (PMJ)

A procedure for developing a nomogram that depicts expectancy of success on a criterion from performance on two predictors is presented. Data from 574 medical students attending Michigan State University College of Human Medicine's classes of 1979 through 1984 were used to develop a model for predicting the expectancy of success on Part I of the…

A procedure for predicting categorical outcomes using categorical predictor variables was described by Moonan. This paper describes a related technique which uses prior probabilities, updated by joint likelihoods, as classification criteria. The procedure differs from Moonan's in that the outcome having the greatest posterior probability is…

The Rasch item analysis model is supposed to yield norm-free estimates of ability and easiness values, but there are several possible interpretations of the nature and extent of such norm-freeness. One such interpretation was that to involve the scores of one single experimental group of testees which were embedded in four differently skewed…

In machine-mediated learning environments, there is a need for more reliable methods of calculating the probability that a learner's response will be correct in future trials. A combination of domain-independent response-state measures of cognition along with two instructional variables for maximum predictive ability are demonstrated. (Author/LRW)

To examine how neighborhood characteristics influence academic achievement, data were drawn from a community survey of low-income neighborhoods and linked with data on performance on standardized testing for third-grade students attending elementary schools in those communities. Results of multilevel logistic regressions indicated that probability…

A study was conducted at Scottsdale and Paradise Valley community colleges to assess the importance of math for the study of economic principles and the extent to which a student's math background determines performance in micro- and macro-economic courses. Students (N=156) from six economic principles classes were surveyed regarding their high…

In evaluation research studies, it often occurs that several program participants (experimentals) drop out of the program prior to completion. Since noncompleters generally differ substantially from completers in many respects, a control group which originally was representative of the participant group will most likely not be representative of…

Uses the various strategies involved in baseball to illustrate basic concepts in game theory. Specifically discusses Willie Mays' base-stealing strategy and how it relates to probability and risk. Reminds students that expected results depend on adopted assumptions. (MJP)