The Future is Bright? Effects of Mood on Perception of the Future

Most people believe that the future will bring them more good things than bad, and therefore have high hopes for the future (MacLeod et al. Cogn Emot 10:69–85, 1996). However, many patients with mood disorders do not hold this positive belief about the future. At the extreme, low expectations of positive outcomes in the future can lead to feelings of hopelessness (O’Connor et al. Psychol Health Med 5:155–161, 2000). This paper aims to extend the literature on subjective probability of future events, using a mood induction paradigm to examine the effects of transient mood change on perceived likelihood of future events in a non-clinical community sample. Participants rated likelihood of future events from a standardized list and from their own lives. Ratings were made in both normal and experimentally-induced positive or negative mood. Results show that self-generated future events were perceived to be more likely than those from a standardized list, and that negative mood significantly biased perceived likelihood of other-generated future events. Participants rating standardized list events saw positive outcomes as less likely and negative outcomes as more likely in induced negative mood than they did in normal mood. Mood had no effect on ratings of self-generated events. Possible directions for future research are discussed.

A foundation for support theory based on a non-Boolean event space

A new foundation is presented for the theory of subjective judgments of probability known in the psychological literature as “Support Theory”. It is based on new complementation operations that, unlike those of classical probability theory (set-theoretic complementation) and classical logic (negation), need not satisfy the principles of the Law of The Excluded Middle and the Law of Double Complementation. Interrelationships between the new complementation operations and the Kahneman and Tversky judgmental heuristic of availability are described.     

Regular Minimality and Thurstonian-type modeling

A Thurstonian-type model for pairwise comparisons is any model in which the response (e.g., “they are the same” or “they are different”) to two stimuli being compared depends, deterministically or probabilistically, on the realizations of two randomly varying representations (perceptual images) of these stimuli. The two perceptual images in such a model may be stochastically interdependent but each has to be selectively dependent on its stimulus. It has been previously shown that all possible discrimination probability functions for same–different comparisons can be generated by Thurstonian-type models of the simplest variety, with independent percepts and deterministic decision rules. It has also been shown, however, that a broad class of Thurstonian-type models, called “well-behaved” (and including, e.g., models with multivariate normal perceptual representations whose parameters are smooth functions of stimuli) cannot simultaneously account for two empirically plausible properties of same–different comparisons, Regular Minimality (which essentially says that “being least discriminable from” is a symmetric relation) and nonconstancy of the minima of discrimination probabilities (the fact that different pairs of least discriminable stimuli are discriminated with different probabilities). These results have been obtained for stimulus spaces represented by regions of Euclidean spaces. In this paper, the impossibility for well-behaved Thurstonian-type models to simultaneously account for Regular Minimality and nonconstancy of minima is established for a much broader notion of well-behavedness applied to a much broader class of stimulus spaces (any Hausdorff arc-connected ones). The universality of Thurstonian-type models with independent perceptual images and deterministic decision rules is shown (by a simpler proof than before) to hold for arbitrary stimulus spaces.     

Two-dimensionalism and the epistemology of recognition

There is reason to expect a reasonable account of a priori knowledge to be linked with an account of the nature of conceptual thought. Recent “two-dimensionalist” accounts of conceptual thought propose an extremely direct connection between the two: on such views, being in a position to know a priori a large number of non-trivial propositions is a necessary condition of concept-possession. In this paper I criticize this view, by arguing that it requires an implausibly internalist and intellectualist conception of capacities we bring to bear in applying concepts in experience. Empirical concept-application depends on the exercise of a variety of capacities, many of which can be grouped together under the general label “recognitional”. As I argue, two-dimensionalism cannot accommodate a plausible account of such capacities. This suggests that the link between a priori knowledge and the nature of conceptual thought is not as direct as twodimensionalists take it to be. I close by briefly sketching a different way to think of that link.

Epistemology without metaphysics

The paper outlines a view of normativity that combines elements of relativism and expressivism, and applies it to normative concepts in epistemology. The result is a kind of epistemological anti-realism, which denies that epistemic norms can be (in any straightforward sense) correct or incorrect; it does allow some to be better than others, but takes this to be goal-relative and is skeptical of the existence of best norms. It discusses the circularity that arises from the fact that we need to use epistemic norms to gather the facts with which to evaluate epistemic norms; relatedly, it discusses how epistemic norms can rationally evolve. It concludes with some discussion of the impact of this view on “ground level” epistemology.

Inference and update

We look at two fundamental logical processes, often intertwined in planning and problem solving: inference and update. Inference is an internal process with which we uncover what is implicit in the information we already have. Update, on the other hand, is produced by external communication, usually in the form of announcements and in general in the form of observations, giving us information that might not have been available (even implicitly) before. Both processes have received attention from the logic community, usually separately. In this work, we develop a logical language that allows us to describe them together. We present syntax, semantics and a complete axiom system; we discuss similarities and differences with other approaches and mention how the work can be extended.     

封面故事、选项框架和损益概率对风险偏好的影响

以股市投资为背景设计决策问题,考查了问题的封面故事类型、备择选项框架和风险项的概率水平对327名股民被试和465名大学生被试的风险偏好的影响。结果表明,股民被试的风险偏好不同于大学生被试,前者在所有实验处理上呈现出稳定的风险回避倾向。大学生被试在不同类型的封面故事下呈现出不同的风险偏好。在传统的坏封面故事下,风险偏好只受到备择选项框架的影响,不受损益概率的影响,即出现经典的框架效应现象。在好封面故事下,风险偏好受到备择选项框架、损益概率及两者交互作用的影响,即在高概率水平上出现框架效应现象,在低概率水平上出现框架效应反转现象     

Comments on “Getting scarred and winning lotteries: Effects of exemplar cuing and statistical format on imagining low‐probability events,” By Newell,Mitchell, and Hayes (2008)

Newell, Mitchell, and Hayes (NMH) conduct three experiments designed to test whether exemplar cuing (EC) theory or a statistical format theory provides a more accurate account for how people make judgments about low‐probability events. They report finding support for the statistical format theory and little or no support for EC. However, NMH misstate the requirements for the production of exemplars in EC theory. As a result, they confuse non‐exemplar conditions with exemplar conditions in their experiments, and find results that are virtually irrelevant to EC theory. Copyright © 2009 John Wiley & Sons, Ltd.