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Research on preference reversals has demonstrated a disproportionate influence of outcome probability on choices between monetary gambles. The aim was to investigate the hypothesis that this is a prominence effect originally demonstrated for riskless choice. Another aim was to test the structure compatibility hypothesis as an explanation of the effect. The hypothesis implies that probability should be the prominent attribute when compared with value attributes both in a choice and a preference–rating procedure. In Experiment 1, two groups of undergraduates were presented with medical treatments described by two value attributes (effectiveness and pain-relief). All participants performed both a matching task and made preference ratings. In the latter task, outcome probabilities were added to the descriptions of the medical treatments for one of the groups. In line with the hypothesis, this reduced the prominence effect on the preference ratings observed for effectiveness. In Experiment 2, a matching task was used to demonstrate that probability was considered more important by a group of participating undergraduates than the value attributes. Furthermore, in both choices and preference ratings the expected prominence effect was found for probability.

This paper examines consumer preferences for the attributes of alternative sources of water supply in Chennai, based on a household survey where respondents were given the description of a set of options. Their decision to choose one of the options is examined using discrete choice models. Whether consumer preferences are hierarchical or lexicographic is also briefly examined. Access to a yard tap is considered to be a more important attribute than water quantity, quality and the provider (the private sector or public sector). In general, the estimated willingness to pay is substantially higher than the present monthly water expenditures. However, some consumers, specially those living in the peri-urban areas, do not seem to be willing to pay for water supply improvements. Among the plausible reasons are a lack of trust in the public utility or a manifestation of the equity politics in India (the peri-urban households claiming their entitlement to subsidized water), or the presence of preference reversal.

ABSTRACTThis paper presents a methodology for analyzing Analytic Hierarchy Process (AHP) rankings if the pairwise preference judgments are uncertain (stochastic). If the relative preference statements are represented by judgment intervals, rather than single values, then the rankings resulting from a traditional (deterministic) AHP analysis based on single judgment values may be reversed, and therefore incorrect. In the presence of stochastic judgments, the traditional AHP rankings may be stable or unstable, depending on the nature of the uncertainty.We develop multivariate statistical techniques to obtain both point estimates and confidence intervals of the rank reversal probabilities, and show how simulation experiments can be used as an effective and accurate tool for analyzing the stability of the preference rankings under uncertainty. If the rank reversal probability is low, then the rankings are stable and the decision maker can be confident that the AHP ranking is correct. However, if the likelihood of rank reversal is high, then the decision maker should interpret the AHP rankings cautiously, as there is a subtantial probability that these rankings are incorrect. High rank reversal probabilities indicate a need for exploring alternative problem formulations and methods of analysis.The information about the extent to which the ranking of the alternatives is sensitive to the stochastic nature of the pairwise judgments should be valuable information into the decision‐making process, much like variability and confidence intervals are crucial tools for statistical inference. We provide simulation experiments and numerical examples to evaluate our method.Our analysis of rank reversal due to stochastic judgments is not related to previous research on rank reversal that focuses on mathematical properties inherent to the AHP methodology, for instance, the occurrence of rank reversal if a new alternative is added or an existing one is deleted.

Objective. In 1978 Congress weakened several key provisions of the Endangered Species Act (ESA), which had been enacted only five years earlier. The objective is to compare alternative explanations for this policy reversal.Methods. Probit and multinomial logit models are used to explain empirically how senators voted in both 1973 and 1978, and to investigate why many senators switched their vote from supporting ESA to weakening it.Results. The findings here indicate that party affiliation and policy‐maker preferences were not important to the 1973 vote, but they were key variables in the 1978 votes and the vote‐switching decision. Proxies for unexpected economic impacts of ESA on individual states have little explanatory power.Conclusions. Ignorance, as measured here, does not appear to explain this policy reversal; rather, an influx of relatively conservative Democrats between 1973 and 1978 presents itself as the leading explanation.

Children with autism are characterized by the absence of functional spontaneous speech. This study assessed whether the type of stimulus materials (preferred versus nonpreferred) would affect the frequency of spontaneous verbal requests in these children. The results of the repeated reversals analysis revealed that the frequency of spontaneous verbal requests was higher in the preferred materials condition than in the nonpreferred materials condition. The results are discussed in relation to issues involving motivation and the development of naturalistic, context-appropriate speech training procedures.