Using self-reported academic cheating from the classes of 1959 through 2002 at the three major United States military service academies (Air Force, Army, and Navy), we measure how peer cheating influences individual cheating behavior. We find higher levels of peer cheating result in a substantially increased probability that an individual will…

A whimsical mathematics event for children and adults, derived from Lewis Carroll's Alice's Adventures in Wonderland, was held at the Providence Children's Museum in Rhode Island. NCTM's Standards were the basis of all the activities. (Contains 10 figures and 1 table.)

Using national transcript data, the authors examine inequality in access to an advanced curriculum in high school and assess the consequences of curricular intensity on test scores and college entry. Inequalities in curricular intensity are primarily explained by student socioeconomic status effects that operate within schools rather than between…

By analyzing the Fisher information allotted to the correct response of a Rasch binary item, Huynh (1994) established the response probability criterion 0.67 (RP67) for standard settings based on bookmarks and item mapping. The purpose of this note is to help clarify the conceptual and psychometric framework of the RP criterion.

The four dominant theories of reasoning from conditionals are translated into formal models: The theory of mental models (Johnson-Laird, P. N., & Byrne, R. M. J. (2002). Conditionals: a theory of meaning, pragmatics, and inference. "Psychological Review," 109, 646-678), the suppositional theory (Evans, J. S. B. T., & Over, D. E. (2004). "If."…

Quantiles for finite mixtures of normal distributions are computed. The difference between a linear combination of independent normal random variables and a linear combination of independent normal densities is emphasized. (Contains 3 tables and 1 figure.)

A survey of psychology graduate admissions committee chairs revealed 5 categories of mistakes applicants make that diminish their probability of acceptance. We discuss 3 strategies that psychology departments can use to decrease the likelihood that students will commit these mistakes in their graduate school applications and provide suggestions…

Consider the nonparametric regression model Y = m(X)+ [tau](X)[epsilon], where X and [epsilon] are independent random variables, [epsilon] has a median of zero and variance [sigma][squared], [tau] is some unknown function used to model heteroscedasticity, and m(X) is an unknown function reflecting some conditional measure of location associated…

Statistical terms are accurate and powerful but can sometimes lead to misleading impressions among beginning students. Discrepancies between the popular and statistical meanings of "conditional" are discussed, and suggestions are made for the use of different vocabulary when teaching beginners in applied introductory courses.

Four experiments tested context switch effects on acquisition and extinction in human predictive learning. A context switch impaired probability judgments about a cue-outcome relationship when the cue was trained in a context in which a different cue underwent extinction. The context switch also impaired judgments about a cue trained in a context…

Cross-validated classification accuracies were compared under assumptions of equal and varying degrees of unequal prior probabilities of group membership for 24 bootstrap and 48 simulated data sets. The data sets varied in sample size, number of predictors, relative group size, and degree of group separation. Total-group hit rates were used to…

A probability distribution was developed for the Andrews-Pregibon (AP) statistic. The statistic, developed by D. F. Andrews and D. Pregibon (1978), identifies multivariate outliers. It is a ratio of the determinant of the data matrix with an observation deleted to the determinant of the entire data matrix. Although the AP statistic has been used…

Classical test theory findings can be derived from the concepts of conditional expectation, conditional independence, and related notions. It is shown that these concepts provide precisely the formalism needed to obtain the classical results with minimal assumptions and with greatest economy in the methods of proof. (RC)

A replication study was conducted to retest the validity of the Neuropsychiatric Hospital Suicide Potential Scale. Fifty four patients who had committed suicide and fifty who had not were the population studied to test, if possible, the limits of prediction the scale can attain by judging the behavior of these patients. (DEP)