An evaluation of the reliability of probability judgments across response modes and over time

Despite the importance of probability assessment methods in behavioral decision theory and decision analysis, little attention has been directed at evaluating their reliability and validity. In fact, no comprehensive study of reliability has been undertaken. Since reliability is a necessary condition for validity, this oversight is significant. The present study was motivated by that oversight. We investigated the reliability of probability measures derived from three response modes: numerical probabilities, pie diagrams, and odds. Unlike previous studies, the experiment was designed to distinguish systematic deviations in probability judgments, such as those due to experience or practice, from random deviations. It was found that subjects assessed probabilities reliably for all three assessment methods regardless of the reliability measures employed. However, a small but statistically significant decrease over time in the magnitudes of assessed probabilities was observed. This effect was linked to a decrease in subjects overconfidence during the course of the experiment.     

Forward inference in risky choice: Mapping gaze and decision processes

The study of cognitive processes is built on a close mapping between three components: overt gaze behavior, overt choice, and covert processes. To validate this overt–covert mapping in the domain of decision‐making, we collected eye‐movement data during decisions between risky gamble problems. Applying a forward inference paradigm, participants were instructed to use specific decision strategies to solve those gamble problems (maximizing expected values or applying different choice heuristics) during which gaze behavior was recorded. We revealed differences between overt behavior, as indicated by eye movements, and covert decision processes, instructed by the experimenter. However, our results show that the overt–covert mapping is for some eye‐movement measures not as close as expected by current decision theory, and hence question reverse inference as being prone to fallacies due to a violation of its prerequisite, that is, a close overt–covert mapping. We propose a framework to rehabilitate reverse inference.     

Identification With All Humanity: The role of self‐definition and self‐investment

Identification With All Humanity (IWAH) relates to higher levels of concern and supportive behavior toward the disadvantaged, stronger endorsement of human rights, and stronger responses in favor of global harmony. So far, IWAH has been conceptualized as a one‐dimensional construct describing the degree with which one identifies with all humans as a superordinate ingroup. However, recent group identification models suggest a multi‐dimensional model to provide a more differentiated approach toward the understanding of the highest level of social identification. Using principal axis (Study 1) and confirmatory (Study 2) factor analyses, we suggest that IWAH sub‐divides into two dimensions—global self‐definition and global self‐investment. Study 2 revealed that global self‐investment was a stronger predictor for both convergent measures (e.g., social dominance orientation and authoritarianism) and behavioral intentions than global self‐definition. Finally, in Study 3, we manipulated IWAH to test its causal effect on donation behavior. Participants in the experimental condition, compared with the control condition, showed higher global self‐investment, which in turn predicted greater giving to global charity. These findings suggest that two dimensions with different behavioral outcomes underlie IWAH.     

Validity of the German Test Anxiety Inventory (TAI‐G) in an Australian sample

Test anxiety (TA) is a prevalent issue among students that can result in deleterious consequences, such as underachievement. However, a contemporary measure that has been validated for use with Australian students seems to be lacking. This study, therefore, investigated the suitability of the German Test Anxiety Inventory (TAI‐G) for use with Australian university students. While the original TAI‐G contains 30 items and was designed to measure four factors (worry, emotionality, interference, and lack of confidence), differing factorial models have been supported in the literature using either the original or a shortened 17‐item version of the measure. These differing TAI‐G models were tested and compared in the current study via confirmatory factor analysis using 224 Australian university students. As expected, results supported the superior fit of the 17‐item four‐factor model. Additionally, the convergent validity of the measure was supported since measures of self‐esteem, self‐efficacy, and general anxiety were all found to correlate significantly with the TAI‐G in the hypothesised directions. Finally, the finding that all of the TAI‐G subscales had acceptably high reliabilities led to the conclusion that the 17‐item TAI‐G is a valid and reliable measure of TA in an Australian university population.     

The Self‐Care of Psychologists and Mental Health Professionals: A Review and Practitioner Guide

It has been documented in the professional literature that psychologists and mental health professionals in general tend to neglect their own mental health, despite serving in a field that promotes the health and well‐being of others. Numerous empirical studies support the need for psychologists and mental health professionals to be more conscientious of the effect that stress and the nature of their work has on them. This article reviews some of the recent literature and discusses the pertinent issues at hand. A number of interventions are suggested along with tips for professionals to consider in order to function in a more productive and ethical fashion.     

Subjective probability and delay.

Human subjects indicated their preference between a hypothetical $1,000 reward available with various probabilities or delays and a certain reward of variable amount available immediately. The function relating the amount of the certain-immediate reward subjectively equivalent to the delayed $1,000 reward had the same general shape (hyperbolic) as the function found by Mazur (1987) to describe pigeons' delay discounting. The function relating the certain-immediate amount of money subjectively equivalent to the probabilistic $1,000 reward was also hyperbolic, provided that the stated probability was transformed to odds against winning. In a second experiment, when human subjects chose between a delayed $1,000 reward and a probabilistic $1,000 reward, delay was proportional to the same odds-against transformation of the probability to which it was subjectively equivalent.     

On the sampling theory roundations of item response theory models

Item response theory (IT) models are now in common use for the analysis of dichotomous item responses. This paper examines the sampling theory foundations for statistical inference in these models. The discussion includes: some history on the stochastic subject versus the random sampling interpretations of the probability in IRT models; the relationship between three versions of maximum likelihood estimation for IRT models; estimating versus estimating -predictors; IRT models and loglinear models; the identifiability of IRT models; and the role of robustness and Bayesian statistics from the sampling theory perspective.A presidential address can serve many different functions. This one is a report of investigations I started at least ten years ago to understand what IRT was all about. It is a decidedly one-sided view, but I hope it stimulates controversy and further research. I have profited from discussions of this material with many people including: Brian Junker, Charles Lewis, Nicholas Longford, Robert Mislevy, Ivo Molenaar, Donald Rock, Donald Rubin, Lynne Steinberg, Martha Stocking, William Stout, Dorothy Thayer, David Thissen, Wim van der Linden, Howard Wainer, and Marilyn Wingersky. Of course, none of them is responsible for any errors or misstatements in this paper. The research was supported in part by the Cognitive Science Program, Office of Naval Research under Contract No. Nooo14-87-K-0730 and by the Program Statistics Research Project of Educational Testing Service.