Empirical underidentification in estimating random utility models: The role of choice sets and standardizations

A standard approach to distinguishing people’s risk preferences is to estimate a random utility model using a power utility function to characterize the preferences and a logit function to capture choice consistency. We demonstrate that with often-used choice situations, this model suffers from empirical underidentification, meaning that parameters cannot be estimated precisely. With simulations of estimation accuracy and Kullback–Leibler divergence measures we examined factors that potentially mitigate this problem. First, using a choice set that guarantees a switch in the utility order between two risky gambles in the range of plausible values leads to higher estimation accuracy than randomly created choice sets or the purpose-built choice sets common in the literature. Second, parameter estimates are regularly correlated, which contributes to empirical underidentification. Examining standardizations of the utility scale, we show that they mitigate this correlation and additionally improve the estimation accuracy for choice consistency. Yet, they can have detrimental effects on the estimation accuracy of risk preference. Finally, we also show how repeated versus distinct choice sets and an increase in observations affect estimation accuracy. Together, these results should help researchers make informed design choices to estimate parameters in the random utility model more precisely.     

Conflict Buffers and Marital Satisfaction: On the Effects of Different Forms of Social Support

This paper deals with the deterioration in the subjective quality of life of women as a result of marital conflict. Whereas primary and secondary prevention are generally targeted at maintaining or increasing the current level of marital happiness this paper focuses on the possibilities for buffering the negative impact of conflict on women’s quality of life. In particular, this paper is interested in the conflict buffering effects of various forms of social support such as home visiting by professional social workers or informal contacts with peers. In order to assess and compare the effectiveness of these forms of tertiary prevention, data from interviews with young mothers in the city of Zurich (Switzerland) will be reanalyzed. The data confirm the phenomenon of stress buffering from social support and reveal variation with regard to the effectiveness of different stress buffers. Female peer support e.g. seems to be at least as successful as home visiting by professional nurses and social workers.     

Maximizing versus matching on concurrent variable-interval schedules

Maximization and matching predictions were examined for a time-based analogue of the concurrent variable-interval variable-ratio schedule. One alternative was a variable interval whose time base operated relatively independent of the schedule chosen, and the other was a discontinuous variable interval for which timing progressed only when selected. Pigeons switched between schedules by pecking a changeover key. The maximization hypothesis predicts that subjects will show a bias toward the discontinuous variable interval and undermatching; however the obtained results conformed closely to the predictions of the matching law. Finally, a quantitative comparison was made of the bias and sensitivity estimates obtained in published concurrent variable-interval variable-ratio analogue studies. Results indicated that only the ratio-based analogue of the concurrent variable interval variable ratio studied by Green, Rachlin, and Hanson (1983) produced significant bias toward the variable-ratio alternative and undermatching, as predicted by reinforcement maximization.     

A Survey of Patients’ Experiences with the Cancer Genetic Counseling Process: Recommendations for Cancer Genetics Programs

In order to promote ongoing quality improvement of not only the Penn State Cancer Genetics Program, but also other cancer risk assessment programs throughout the country, we developed, piloted and conducted a survey to explore patient expectations, experiences, and satisfaction with the cancer genetic counseling process. The comprehensive survey was mailed to 340 eligible patients, 156 (45.9%) of whom returned the completed survey within the allotted time. Responses to closed-ended questions were tallied and open-ended questions were content analyzed. Major findings show that: (1) Patients were seeking cancer-related information and support throughout the cancer risk assessment process and were interested in participating in available research studies; (2) The setting in which patients are seen for cancer risk assessment may pose potential emotional ramifications; (3) Misperceptions regarding insurance discrimination and lack of insurance coverage persist; (4) Patients view the genetic counselor as responsible for updating them about new discoveries. Specific recommendations for cancer genetics programs are included.     

Reinforcement value and substitutability of sucrose and wheel running: implications for activity anorexia

Choice between sucrose and wheel-running reinforcement was assessed in two experiments. In the first experiment, ten male Wistar rats were exposed to concurrent VI 30 s VI 30 s schedules of wheel-running and sucrose reinforcement. Sucrose concentration varied across concentrations of 2.5, 7.5, and 12.5%. As concentration increased, more behavior was allocated to sucrose and more reinforcements were obtained from that alternative. Allocation of behavior to wheel running decreased, but obtained wheel-running reinforcement did not change. Overall, the results suggested that food-deprived rats were sensitive to qualitative changes in food supply (sucrose concentration) while continuing to defend a level of physical activity (wheel running). In the second study, 15 female Long Evans rats were exposed to concurrent variable ratio schedules of sucrose and wheel-running, wheel-running and wheel-running, and sucrose and sucrose reinforcement. For each pair of reinforcers, substitutability was assessed by the effect of income-compensated price changes on consumption of the two reinforcers. Results showed that, as expected, sucrose substituted for sucrose and wheel running substituted for wheel running. Wheel running, however, did not substitute for sucrose; but sucrose partially substituted for wheel running. We address the implications of the interrelationships of sucrose and wheel running for an understanding of activity anorexia.     

Fix and sample with rats in the dynamics of choice

The generality of the molar view of behavior was extended to the study of choice with rats, showing the usefulness of studying order at various levels of extendedness. Rats' presses on two levers produced food according to concurrent variable-interval variable-interval schedules. Seven different reinforcer ratios were arranged within each session, without cues identifying them, and separated by blackouts. To alternate between levers, rats pressed on a third changeover lever. Choice changed rapidly with changes in component reinforcer ratio, and more presses occurred on the lever with the higher reinforcer rate. With continuing reinforcers, choice shifted progressively in the direction of the reinforced lever, but shifted more slowly with each new reinforcer. Sensitivity to reinforcer ratio, as estimated by the generalized matching law, reached an average of 0.9 and exceeded that documented in previous studies with pigeons. Visits to the more-reinforced lever preceded by a reinforcer from that lever increased in duration, while all visits to the less-reinforced lever decreased in duration. Thus, the rats' performances moved faster toward fix and sample than did pigeons' performances in previous studies. Analysis of the effects of sequences of reinforcer sources indicated that sequences of five to seven reinforcers might have sufficed for studying local effects of reinforcers with rats. This study supports the idea that reinforcer sequences control choice between reinforcers, pulses in preference, and visits following reinforcers.     

Choice between single and multiple reinforcers in concurrent-chains schedules

Pigeons responded on concurrent-chains schedules with equal variable-interval schedules as initial links. One terminal link delivered a single reinforcer after a fixed delay, and the other terminal link delivered either three or five reinforcers, each preceded by a fixed delay. Some conditions included a postreinforcer delay after the single reinforcer to equate the total durations of the two terminal links, but other conditions did not include such a postreinforcer delay. With short initial links, preference for the single-reinforcer alternative decreased when a postreinforcer delay was present, but with long initial links, the postreinforcer delays had no significant effect on preference. In conditions with a postreinforcer delay, preference for the single-reinforcer alternative frequently switched from above 50% to below 50% as the initial links were lengthened. This pattern of results was consistent with delay-reduction theory (Squires & Fantino, 1971), but not with the contextual-choice model (Grace, 1994) or the hyperbolic value-added model (Mazur, 2001) as they have usually been applied. However, the hyperbolic value-added model could account for the results if its calculations were expanded to include reinforcers delivered in later terminal links. The implications of these findings for models of concurrent-chains performance are discussed.     

Factors Moderating Children's Adjustment to Parental Separation: Findings From a Community Study in England

Research findings show that there is marked variability in children's response to parental separation, but few studies identify the sources of this variation. This prospective longitudinal study examines the factors modifying children's adjustment to parental separation in a community sample of 5,635 families in England. Children's behavioral/emotional problems were assessed when children were aged 47 and 81 months; marital quality, maternal depression, socioeconomic circumstances, and demographic variables were assessed prior to the separation from maternal report. Results indicated that 346 mothers separated from their partners in the 3-year period. Preseparation differences were found for measures of family process and parent risk factors, with effect sizes ranging from small to trivial. Parental separation was associated with a significant but modest increase in behavioral/emotional problems, independent of marital quality, maternal depression, socioeconomic circumstances, and demographic variables. Moderation analyses showed that children of cohabiting parents had a greater increase in adjustment problems following parental separation than children of married parents. Further research elucidating the factors that moderate children's adjustment to parental separation is needed to improve our understanding of who may most likely benefit from preventive interventions.     

Conceptions of career choice and attainment: Developmental levels in how children think about careers

Children’s Conceptions of career choice and attainment were evaluated in two studies to test whether reasoning levels varied by grade level (Studies 1 and 2) and perspective-taking complexity (Study 2). Results indicated that younger children (Grade K) were more likely to use reasoning strategies associated with fantasy and magical thinking and older children (Grade 6) were more likely to consider personal interests, abilities, and job requirements. Study 2 replicated these results and also found that children evaluated as able to use more complex perspective-taking reported higher reasoning levels when discussing their Conceptions of career choice and attainment.     

Trait emotional intelligence profiles of students from different university faculties

This study investigated the trait emotional intelligence (trait EI or trait emotional self‐efficacy) profiles of 512 students from five university faculties: technical studies, natural sciences, social sciences, arts, and humanities. Using the Trait Emotional Intelligence Questionnaire, it was hypothesised that (a) social sciences would score higher than technical studies in Emotionality, (b) arts would score higher than technical studies in Emotionality, (c) arts would score lower than technical studies in Self‐control, and (d) there would be an interaction between gender and faculty, whereby female students would score higher than male students within the social sciences only. Several other exploratory comparisons were also performed. Results supported hypotheses (a), (b), and (d), but not hypothesis (c), although the differences were in the predicted direction.