Individual differences in reverse Hindsight bias: I never thought something like chernobyl would happen. Did I?

Hindsight bias was studied in the context of the accident in the Chernobyl nuclear power plant, which took place on April 26th 1986. An individual difference factor which relates to the motivation to process information, need for cognition, was expected to moderate the occurrence of hindsight bias. Probability estimates of many casualties due to the use of nuclear power in The Netherlands were obtained from 212 individuals two months before the accident in Chernobyl. These estimates were compared with similar estimates made in hindsight by the same individuals five months after the accident. Loglinear Analyses reveal a systematic hindsight bias. However, the direction of the bias was contrary to expectations. In hindsight, individuals gave lower probabilities than they actually did two months before the Chernobyl accident. These results reveal a reverse hindsight bias. As hypothesized, need for cognition moderates hindsight bias: individuals low and medium in need for cognition express a systematic reverse hindsight bias, while individuals high in need for cognition do not. High need for cognition individuals also show higher literal consistency between the two measurements, which supports a memory explanation of the moderating effect of need for cognition.     

Decomposition of multivariate utility functions in non-additive expected utility theory

In expected utility many results have been derived that give necessary and/or sufficient conditions for a multivariate utility function to be decomposable into lower-dimensional functions. In particular, multilinear, multiplicative and additive decompositions have been widely discussed. These utility functions can be more easily assessed in practical situations. In this paper we present a theory of decomposition in the context of nonadditive expected utility such as anticipated utility or Choquet expected utility. We show that many of the results used in conventional expected utility carry over to these more general frameworks. If preferences over lotteries depend only on the marginal probability distributions, then in expected utility the utility function is additively decomposable. We show that in anticipated utility the marginality condition implies not only that the utility function is additively decomposable but also that the distortion function is the identity function. We further demonstrate that a decision maker who is bivariate risk neutral has a utility function that is additively decomposable and a distortion function q for which q(½) = ½.     

Can > Will: Predictions of What Can Happen are Extreme,but Believed to be Probable

Predictions of uncertain events are often described in terms of what can or what will happen. How are such statements used by speakers, and what are they perceived to mean? Participants in four experiments were presented with distributions of variable product characteristics and were asked to generate natural, meaningful sentences containing either will or can. Will was typically associated with either low or intermediate numeric values, whereas can consistently suggested high (maximum) values. For instance, laptop batteries lasting from 1.5 to 3.5 hours will last for 1.5 hours or for 2.5 hours, but they can last for 3.5 hours. The same response patterns were found for positive and negative events. In will‐statements, the most frequent scalar modifiers were at least and about, whereas in can‐statements, the most frequent modifier included up to. A fifth experiment showed that will indicates an outcome that may be certain but more often simply probable. Can means possible, but even can‐statements are perceived to imply probable outcomes. This could create a communication paradox because most speakers use can to describe outcomes that because of their extremity are at the same time quite unlikely. Copyright © 2011 John Wiley & Sons, Ltd.     

A randomised Monty Hall experiment: The positive effect of conditional frequency feedback

The Monty Hall dilemma (MHD) is a notorious probability problem with a counterintuitive solution. There is a strong tendency to stay with the initial choice, despite the fact that switching doubles the probability of winning. The current randomised experiment investigates whether feedback in a series of trials improves behavioural performance on the MHD and increases the level of understanding of the problem. Feedback was either conditional or non-conditional, and was given either in frequency format or in percentage format. Results show that people learn to switch most when receiving conditional feedback in frequency format. However, problem understanding does not improve as a consequence of receiving feedback. Our study confirms the dissociation between behavioural performance on the MHD, on one hand, and actual understanding of the MHD, on the other. We discuss how this dissociation can be understood.     

Daydreams and trait affect: The role of the listener’s state of mind in the emotional response to music

Music creates room for the mind to wander, mental time travel, and departures into more fantastical worlds. We examined the mediating role of daydreams and the moderating function of personality differences for the emotional response to music by using a moderated mediation approach. The results showed that the valence of daydreams played a mediating role in the reaction to the musical experience: happy music was related to more positive daydreams, which were associated with greater relaxation with the happy music and to greater liking of the happy music. Furthermore, negative affect (trait) moderated the direct effect of sad vs. happy music on the liking of the music: individuals with high scores on negative affect preferred sad music. The results are discussed with regard to the interplay of general and personality-specific processes as it is relevant to better understand the effects music can have on the listeners.     

Ranking Theory and Conditional Reasoning

Ranking theory is a formal epistemology that has been developed in over 600 pages in Spohn's recent book The Laws of Belief, which aims to provide a normative account of the dynamics of beliefs that presents an alternative to current probabilistic approaches. It has long been received in the AI community, but it has not yet found application in experimental psychology. The purpose of this paper is to derive clear, quantitative predictions by exploiting a parallel between ranking theory and a statistical model called logistic regression. This approach is illustrated by the development of a model for the conditional inference task using Spohn's (2013) ranking theoretic approach to conditionals.     

Euclid: Strategic alternative assessment matrix

The vast amount of information that must be considered to solve inherently ill‐structured and complex strategic problems creates a need for tools to help decision makers (DMs) recognize the complexity of this process and develop a rational model for strategy evaluation. Over the last several decades, a philosophy and a body of intuitive and analytical methods have been developed to assist DMs in the evaluation of strategic alternatives. However, the intuitive methods lack a structured framework for the systematic evaluation of strategic alternatives while the analytical methods are not intended to capture intuitive preferences. Euclid is a simple and yet sophisticated multiobjective value analysis model that attempts to uncover some of the complexities inherent in the evaluation of strategic alternatives. The proposed model uses a series of intuitive and analytical methods including environmental scanning, the analytic hierarchy process (AHP), subjective probabilities, and the theory of displaced ideal, to plot strategic alternatives on a matrix based on their Euclidean distance from the ideal alternative. Euclid is further compared to the quantitative strategic planning matrix (QSPM) in a real world application. The information provided by the users shows that Euclid can significantly enhance decision quality and the DM's confidence. Euclid is not intended to replace the DMs, rather, it provides a systematic approach to support, supplement, and ensure the internal consistency of their judgments through a series of logically sound techniques. Copyright © 2003 John Wiley & Sons, Ltd.     

Conditionals,Context, and the Suppression Effect

Modus ponens is the argument from premises of the form If A, then B and A to the conclusion B (e.g., from If it rained, Alicia got wet and It rained to Alicia got wet). Nearly all participants agree that the modus ponens conclusion logically follows when the argument appears in this Basic form. However, adding a further premise (e.g., If she forgot her umbrella, Alicia got wet) can lower participants’ rate of agreement—an effect called suppression. We propose a theory of suppression that draws on contemporary ideas about conditional sentences in linguistics and philosophy. Semantically, the theory assumes that people interpret an indicative conditional as a context‐sensitive strict conditional: true if and only if its consequent is true in each of a contextually determined set of situations in which its antecedent is true. Pragmatically, the theory claims that context changes in response to new assertions, including new conditional premises. Thus, the conclusion of a modus ponens argument may no longer be accepted in the changed context. Psychologically, the theory describes people as capable of reasoning about broad classes of possible situations, ordered by typicality, without having to reason about individual possible worlds. The theory accounts for the main suppression phenomena, and it generates some novel predictions that new experiments confirm.