George Karabatsos

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An outline is given of the behavioral properties (axioms) that have been proposed, and to some extent empirically evaluated, concerning uncertain (often risky) alternatives, the joint receipt of alternatives, and possible linking properties. Recent theoretical work has established the existence of three inherently distinct risk types of people—risk seeking,(More)
This research describes some of the similarities and differences between additive conjoint measurement (a type of fundamental measurement) and the Rasch model. It seems that there are many similarities between the two frameworks, however, their differences are nontrivial. For instance, while conjoint measurement specifies measurement scales using a(More)
A new statistical methodology is developed for the analysis of spontaneous adverse event (AE) reports from post-marketing drug surveillance data. The method involves both empirical Bayes (EB) and fully Bayes estimation of rate multipliers for each drug within a class of drugs, for a particular AE, based on a mixed-effects Poisson regression model. Both(More)
In the framework of dichotomous response data, this study develops Markov Chain Monte Carlo estimation theory for an item response model that estimates the answer key, in addition to respondent competence (ability), response bias, and item difficulty parameters. This model unifies ideas of test theory and latent structure analysis, as the estimated(More)
We propose a mixed multinomial logit model, with the mixing distribution assigned a general (nonparametric) stick-breaking prior. We present a Markov chain Monte Carlo (MCMC) algorithm to sample and estimate the posterior distribution of the model's parameters. The algorithm relies on a Gibbs (slice) sampler that is useful for Bayesian nonparametric(More)
The Sexual Experiences Survey (Koss, Gidycz, & Wisniewski, 1987) is a commonly used instrument for assessing various degrees of sexual aggression and victimization among male offenders and female victims. Rasch analysis was used to transform qualitative raw score observations into objective linear measures using the responses of a national sample of 6,159(More)
In a meta-analysis, it is important to specify a model that adequately describes the effect-size distribution of the underlying population of studies. The conventional normal fixed-effect and normal random-effects models assume a normal effect-size population distribution, conditionally on parameters and covariates. For estimating the mean overall effect(More)