Research has consistently shown that older students--those who enter college for the first time at age 25 or older--are less likely to complete a degree or certificate. The authors estimate a single-risk discrete-time hazard model using transcript data on a cohort of first-time community college students in Florida to compare the educational…

Purchase probability as a function of interpurchase time was examined through comparison of findings from laboratory experiments on reinforcement schedules and from marketing investigations of consumers' interpurchase time. Panel data, based on a sample of 80 consumers who purchased nine supermarket food products during 16 weeks, were used. For…

Mediators are variables that explain the association between an independent variable and a dependent variable. Structural equation modeling (SEM) is widely used to test models with mediating effects. This article illustrates how to construct confidence intervals (CIs) of the mediating effects for a variety of models in SEM. Specifically, mediating…

This article proposes an intuitive approach for predictive discriminant analysis with mixed continuous, dichotomous, and ordered categorical variables that are defined via an underlying multivariate normal distribution with a threshold specification. The classification rule is based on the comparison of the observed data logarithm probability…

This study examined the factor structure, reliability, and validity of the Suicide Probability Scale (SPS) in a sample of 226 (80 male, 146 female) adolescent psychiatric inpatients. Confirmatory factor analyses provided only some support for the original subscales. Exploratory factor analyses revealed some overlap with the original scales, but…

A number of methods are available in the literature to measure confidence intervals. Here, confidence intervals for estimating the population mean of a skewed distribution are considered. This note proposes two alternative confidence intervals, namely, Median t and Mad t, which are simple adjustments to the Student's t confidence interval. In…

People's reactions to coincidences are often cited as an illustration of the irrationality of human reasoning about chance. We argue that coincidences may be better understood in terms of rational statistical inference, based on their functional role in processes of causal discovery and theory revision. We present a formal definition of…

This paper provides information about the importance of non-pecuniary school characteristics, such as race and poverty, on teacher turnover in Georgia. Simple descriptive statistics indicate that new teachers are more likely to leave schools with lower test scores, lower income, or higher proportions of minorities. A linear probability and a…

The failure of Hume's "constant conjunction" to describe apparently causal relations in science and everyday life has led to various "probabilistic" theories of causation of which the study by P. C. Suppes (1970) is an important example. A formal model that was developed for the analysis of comparative agricultural experiments…

Report describes the rationale underlying a procedure for eliciting personal estimates of probabilities utilizing a proper scoring rule, and illustrates some new techniques for calibrating those probabilities and providing better feedback to students learning to assess uncertainty. (Author)

THIS BIBLIOGRAPHY SUPPLEMENT LISTS MATERIALS ON VARIOUS ASPECTS OF ACHIEVEMENT. APPROXIMATELY 60 REFERENCES ARE PROVIDED TO DOCUMENTS DATING FROM 1961 TO 1966. JOURNALS, BOOKS, AND REPORT MATERIALS ARE LISTED. SUBJECT AREAS INCLUDED ARE ACHIEVEMENT LEVEL, ACADEMIC ACHIEVEMENT, ACHIEVEMENT MOTIVATION, UNDERACHIEVERS, PROBABILITY ESTIMATES, AND…

The defining property of an admissible scoring system is that any individual perceives himself as maximizing his expected score by reporting his true subjective distribution. The use of admissible scoring systems as a measure of probabilistic forecasts is becoming increasingly well-known in those cases where the forecast is a discrete distribution…

A FORTRAN computer program is described which computes F ratios and attendant probabilities for two-factor fixed effects analysis of variance designs with disproportional cell frequencies. The number of levels for each factor is limited to five and all zero values are considered to be equivalent to missing values. (Author/JKS)

Compares the harmonic mean and Kramer unequal group forms of the Tukey test for various: (a) degrees of disparate group sizes, (b) numbers of groups, and (c) nominal significant levels. (RC)