Looking back versus looking ahead: framing of time and work at different stages of a project

Progress on a well‐defined project can be described along a task dimension in terms of amount done, or as amount of work still to be completed. Time‐limited projects can also be described on a temporal dimension in terms of time spent versus time left. Five experiments are reported showing that such frames have predictable implications for speakers as well as for listeners: Statements by a team leader about time spent and work left are perceived as suggestions to “hurry up,” whereas complementary statements about work done and time left indicate that the team can take it more easy. The first set of statements further implies that the team is behind schedule, whereas the last two statements suggest that the team is ahead of the plan. In line with this, speakers preferred work done and time left statements when they were ahead of schedule, but not when they were behind. “Hurry up” and “behind schedule” interpretations were also shown to be dependent upon stage, being more prominent in the final stages than during the initial stages of a project. Copyright © 2005 John Wiley & Sons, Ltd.     

Associated Factors of Suicide Among University Students: Importance of Family Environment

The aim in this study was to underline the importance of family environment as a significant associate of suicide probability among university students. For this aim 226 Turkish university students completed Suicide Probability Scale, Family Environment Questionnaire, Beck Depression Inventory, and Positive and Negative Affect Scale. As a result of the formulated regression analysis, after controlling for the 51% of the total variance accounted for by the control variables (i.e., gender, age, living with family versus away from family, and Grade Point Averages) and mood related variables (i.e., depressive symptoms, and positive and negative affect), family cohesion still emerged as a significant associate of the suicide probability. These findings underline the importance of family relations as a risk factor of suicide among university students.This work has been supported by the Turkish Academy of Sciences, in the framework of the Young Scientist Award Program. (TG-TUBA-GEBİP/2002-1-11).     

主体关联性对贝叶斯推理概率估计的影响

用贝叶斯推理问题为实验材料,探讨了主体关联性对贝叶斯推理概率估计的影响。结果表明,当估计的事件与主体有关时,被试对消极事件概率估计较低,对积极事件概率估计值;当估计的事件与主体无关时,被试对消极事件和积极事件的概率估计无显著差异。反应时分析表明,被试对消极事件的概率估计比对积极事件的概率估计时间显著地长,当消极事件与主体有关时概率估计时间就更长;而对积极事件的概率估计,与主体有关和与主体无关时反应时差异不显著。这表明,被试对消极事件的概率估计(特别是消极事件与己有关时)更为慎重。     

Framing experts' (dis)agreements about uncertain environmental events

Agreements and disagreements between expert statements influence lay people's beliefs. But few studies have examined what is perceived as a disagreement. We report six experiments where people rated agreement between pairs of probabilistic statements about environmental events, attributed to two different experts or to the same expert at two different points in time. The statements differed in frame, by focusing on complementary outcomes (45% probability that smog will have negative health effects vs. 55% probability that it will not have such effects), in probability level (45% vs. 55% probability of negative effects), or in both respects. Opposite frames strengthened disagreement when combined with different probability levels. Approximate probabilities can be “framed” in yet another way by indicating reference values they are “over” or “under”. Statements that use different directional verbal terms (over vs. under 50%) indicated greater disagreement than statements with the same directional term but different probability levels (over 50% vs. over 70%). Framing and directional terms similarly affected consistency judgments when both statements were issued by the same expert at different occasions. The effect of framing on perceived agreement was significant for medium (10 and 20 percentage points) differences between probabilities, whereas the effect of directional term was stable for numerical differences up to 40 percentage points. To emphasize agreement between different estimates, they should be framed in the same way. To accentuate disagreements or changes of opinion, opposite framings should be used.     

What shapes the probability weighting function? Influence of affect,numeric competencies,and information formats

Research suggests that people are less sensitive to variations in probability in affect‐rich compared with affect‐poor risky choices. This effect is modeled by a more curved probability weighting function (PWF). We investigated the role of different numeric competencies and the effectiveness of several intervention strategies to decrease this affect‐laden probability distortion. In two experiments, we manipulated the affect‐richness of a risky prospect. In Experiment 1 (N = 467), we measured numeracy and symbolic‐number mapping (i.e., the ability to accurately map numbers onto their underlying magnitudes). The affect‐based manipulations showed the expected effects only in participants with more accurate symbolic‐number mapping, who also reported more differentiated emotional reactions to the various probabilities and displayed more linear PWFs. Instructions to focus on the probability information decreased probability distortion and revealed differences in the use of probability information on the basis of symbolic‐number mapping ability. In Experiment 2 (N = 417), we manipulated the format in which the probability information was presented: using visual aids versus no visual aids and a positive frame (e.g., one person wins) versus combined frame (e.g., one person wins and 99 persons do not win). The affect‐based manipulations had no effect but both the visual aids and combined frame decreased probability distortion. Whereas affect‐richness manipulations require further research, results suggest that probability weighting is at least partially driven by the inability to translate numerical information into meaningful and well‐calibrated affective intuitions. Visual aids and simple framing manipulations designed to calibrate these intuitions can help decision makers extract the gist and increase sensitivity to probabilities.     

A survey on adverse incidents in legal psychology studies: Reflections on ethics review

Ethics committees (ECs) regulate research activities to maintain research participants' autonomy and to protect them from harm and injury. No research to date attempted to establish how much risk is involved in social‐science research. Using a survey approach, we set out to estimate the risk of being involved in an incident for research participants in legal psychology and assessed researchers' views of ECs. Fifty‐nine of 188 respondents (31%) stated that they had experienced one or more incidents with a participant. The estimated risk of being involved in an incident was one to three per 10,000 participants, which according to biomedical standards defines a rare risk. Although some researchers were satisfied with their EC, the general tenor was one of discontent due to conservative decision‐making, lacking expertise, and overstepping demands. Whether ECs succeed in protecting participants from loss of autonomy, harm and injury are unknown but are open to empirical research.     

Getting scarred and winning lotteries: effects of exemplar cuing and statistical format on imagining low‐probability events

Three experiments tested the exemplar cuing and frequency format accounts of how the ‘imaginability’ of low‐probability events is enhanced. The experiments manipulated imaginability by varying the statistics used to describe negative (e.g. being scarred as a result of laser surgery) and positive (e.g. winning a lottery) low‐probability events. The results strongly supported the frequency format account, whereby imaginability is enhanced through the use of frequency formats for conveying statistical information (e.g. 20 out of 2000 as opposed to 0.01%). However, only limited support was found for exemplar cuing (EC) theory. Overall the results support the claim that the imaginability of outcomes plays a key role in thinking about low‐probability events, but question the mechanisms specified by EC theory for mediating such effects. Copyright © 2007 John Wiley & Sons, Ltd.     

Social discounting and delay discounting

Social discounting was measured as the amount of money a participant was willing to forgo to give a fixed amount (usually $75) to another person. In the first experiment, amount forgone was a hyperbolic function of the social distance between the giver and receiver. In the second experiment, degree of social discounting was an increasing function of reward magnitude whereas degree of delay discounting was a decreasing function of reward magnitude. In the third experiment, the shape of the function relating delayed rewards to equally valued immediate rewards for another person was predicted from individual delay and social discount functions. All in all, the studies show that the social discount function, like delay and probability discount functions, is hyperbolic in form. Copyright © 2007 John Wiley & Sons, Ltd.     

Horgan on Sleeping Beauty

With the notable exception of David Lewis, most of those writing on the Sleeping Beauty problem have argued that 1/3 is the correct answer. Terence Horgan has provided the clearest account of why, contrary to Lewis, Beauty has evidence against the proposition that the coin comes up heads when she awakens on Monday. In this paper, I argue that Horgan’s proposal fails because it neglects important facts about epistemic probability.     

Synchronic Bayesian updating and the Sleeping Beauty problem: reply to Pust

I maintain, in defending “thirdism,” that Sleeping Beauty should do Bayesian updating after assigning the “preliminary probability” 1/4 to the statement S: “Today is Tuesday and the coin flip is heads.” (This preliminary probability obtains relative to a specific proper subset I of her available information.) Pust objects that her preliminary probability for S is really zero, because she could not be in an epistemic situation in which S is true. I reply that the impossibility of being in such an epistemic situation is irrelevant, because relative to I, statement S nonetheless has degree of evidential support 1/4.