An empirical comparison of several methods for testing the equality of dependent proportions

Three methods for testing the equality of nonindependent proportions were compared with, the use of Monte Carlo techniques. The three methods included Cochran's test, an ANOVA F test, and Hotelling's T² test. With respect to empirical significance levels, the ANOVA F test is recommended as the preferred method of analysis.

Oftentimes an experimenter is interested in testing the equality of several proportions. When the proportions are independent Kemp and Butcher (1972) and Butcher and Kemp (1974) compared several methods for analysing large sample binomial data for the case of a 3 x 3 factorial design without replication. In addition, Levy and Narula (1977) compared many of the same methods for analyzing binomial data; however, Levy and Narula investigated the relative utility of the methods for small sample sizes.     

Bayesian analysis of prevalence from the results of small screening samples

Bayesian analysis is applied to the number of cases screened positive to estimate the disease prevalence and to predict the number of future cases with disease. The analysis makes use of additional experimental information about the test’s sensitivity and specificity and of prior information on the prevalence of disease. Prior and posterior probability distributions of disease prevalence are conjugate mixtures of Beta densities and can be expressed in exact algebraic form.     

Bayesian coverage optimization models

Finding a subset collection that provides optimal population coverage is a frequently encountered deterministic problem. A random sample is often used to formulate the optimal coverage (OC) model, which is then used to select the subsets that provide the estimated optimal population coverage. Such problems are ubiquitous and occur in both the public and private sectors; examples include media selection, placement of municipal services such as sirens and waste dumps, and reserve site selection. Conceptualizing sample elements as counts in a contingency table, we show how decision-makers can combine prior information with sample data to help formulate OC models. We consider conjugate and vague priors with classical and empirical Bayesian interpretations. We show that the predictive approach yields a common marketing exposure model that has previously been justified empirically. Finally, we demonstrate the potential importance of our results on problems generated from a well-known example from the literature.     

Measuring older women’s resilience: Evaluating the suitability of the Connor-Davidson Resilience Scale and the Resilience Scale

ABSTRACT

The author provides conceptual and operational definitions of the construct of resilience in the context of research with older adults (aged 60 years or older). Two psychometric instruments (the Connor-Davidson Resilience Scale and the Resilience Scale) are described. The psychometric properties of each instrument are discussed in relation to the research of the original developers of the tools and research conducted by other investigators. Research on the resilience of older women has yet to be initiated. The author evaluated the psychometric properties of both instruments to determine their suitability for investigation of resilience in older women.     

Looking Back as We Look Ahead: Integrating Research, Theory, and Practice on Intergroup Relations

This article looks back at the origins of intergroup relations in social psychology just over 50 years ago. Pioneers in the field—Robin Williams, Gordon Allport, and Kurt Lewin—were all deeply concerned with integrating social science and social action. We seek to re-center this mutuality of research and practice, and to expand the focus of intergroup relations from prejudice reduction to social inclusion. The articles in this issue document cutting-edge research, theory, and practice, and make substantive contributions to the future of intergroup relations. A unique feature of this issue is a set of commentaries by prominent scholars and practitioners in the fields of intergroup relations and education. Walter Stephan, James Banks, Thomas Pettigrew, and Patricia Gurin each reflect on the collection of articles through the lens of their own personal and professional biographies to help define the intersections of research, theory, and practice on intergroup relations.     

Corrigendum to “Discounted Stochastic Games With No Stationary Nash Equilibrium: Two Examples”

Levy (2013) presented examples of discounted stochastic games that do not have stationary equilibria. The second named author has pointed out that one of these examples is incorrect. In addition to describing the details of this error, this note presents a new example by the first named author that succeeds in demonstrating that discounted stochastic games with absolutely continuous transitions can fail to have stationary equilibria.     

Terror and trade of individual investors

A great number of psychological studies document the influence of emotions on individuals’ decision-making processes. This paper contributes to this literature by analyzing the possible impact of terrorism on financial trade by individual investors. Using account data for over 3000 households obtained from a large Israeli bank, we look into reactions of common stock investments to terrorist incidents in the years 1998–2002. The empirical analysis indicates that terror has a significant adverse effect on actual trade, possibly limiting the scope of risk-sharing available through traded securities. Several psychological explanations for investors’ reluctance to trade are provided. Amongst them are the increase in public fear (resulting in pessimistic risk estimates and risk averse choices); the sense of ambiguity caused by terror; repercussions of anxiety and depression disorders; a desire to avoid future regret. Our results add to the recent literature documenting the harmful effects terrorist acts have on various facets of the economy.