数字记忆广度对策略应用模式的影响──中美儿童计算能力差异的比较研究

本研究旨在了解中美儿童在策略运用模式上的差异是否与数字记忆广度有关。为此,分别测验了中美幼儿园儿童的加法技能,数字记忆广度,并通过一组计算机呈现的加法作业评估儿童使用的解题策略。结果表明,中国儿童的基本算术技能和数学记忆广度均超过同龄的美国儿童。在解题时,中国儿童多使用效率较高的言语计算策略,美国儿童则多采用计数手指策略,在言语计数策略和检索策略的加工速度上中国儿童也超过美国儿童。相关分析表明．策略应用模式的文化差异与数字记忆广度有关。比较大的工作记忆容量增加了数字线索可利用的资源,为儿童早期言语计数能力的发展提供了有利条件。     

Risky choice as a function of amount and variance in food supply.

In Experiment 1, 4 rats earned their daily food ration by choosing on a trials basis between a "risky" and a "riskless" lever. The risky lever produced either 15 45-mg food pellets or no pellets, and on average provided five pellets per choice. The riskless lever always produced three pellets. Across conditions, the number of trials per session was varied. Body weight and choice of the risky lever decreased as the number of trials per session decreased, even though body weight could only be defended by increased choice of the risky lever. In Experiment 2, trials per session were fixed, but the number of pellets delivered by the risky and riskless levers was either at the same level as in Experiment 1 or tripled from those levels. Now choice of the risky lever was inversely related to the size of reinforcement and to body weight. The results of these experiments show that risk aversion covaries with the amount of food available in a session and the daily variance in the amount of food earned.     

Framing of Decisions: Effect on Active and Passive Risk Avoidance

Decision makers intending to avoid risk in a decision situation can choose a less risky alternative (passive risk avoidance) or intervene actively in an alternative applying a risk‐defusing action (active risk avoidance). In Experiment 1 (64 participants), we compared active and passive risk defusing in two framing conditions. In the negative frame, in the uncertain alternative, a change to the worse was possible; in the positive frame, a change to an improvement was possible. Each participant decided in both framing conditions. As expected, active risk avoidance behavior for preventing a negative outcome (i.e., in the negative frame) was more likely than for promoting a positive one (i.e., in the positive frame). If decision makers did not or could not actively defuse the risk, they chose in correspondence to the classical pattern: risk avoidance in the positive frame and risk seeking in the negative one. We replicated the latter result in a second experiment (32 participants). The classical framing pattern in passive risk avoidance in both experiments is remarkable, because participants were not presented or did not search for exact probabilities. Copyright © 2014 John Wiley & Sons, Ltd.     

“All‐or‐None” Versus “Most‐or‐Some” Options in Risky Choice: Effects of Domain and Handedness

Two methodological variants of Kahneman and Tversky's Asian disease scenario were investigated. One variant involved replacing the “all‐or‐none” outcome scenarios of the risky choice with “most‐or‐some” scenario outcomes, and the second variant involved replacing the negative domain of lives lost with a positive domain of jobs created. In addition, the effects of strength of handedness, a variable related to individual differences in risk perception, were examined. Results indicated that standard framing effects were obtained across both domains, with a decrease in risky choice under the gain domain. Scenario type also interacted with handedness, such that the all‐or‐none scenario yielded framing effects for consistent (strong)‐handers only, whereas the most‐or‐some scenario yielded framing effects for inconsistent (mixed)‐handers only (consistent‐handers are those who use the same hand exclusively for almost all activities). These results demonstrate that framing effects are strongly influenced by the presence versus absence of extreme/absolute outcomes and that individuals (in this case, decision makers with varying degrees of handedness strength) are differentially sensitive to different pieces of information. Copyright © 2014 John Wiley & Sons, Ltd.     

Impact of alcohol on sexual decision making: Intentions to have unprotected sex

The impact of alcohol on intentions to have sex with a new partner and the antecedents of intentions were investigated in three studies (N = 139, 60, and 218, respectively). In all three studies, respondents were intoxicated or not intoxicated with alcohol and completed measures based on the Theory of Planned Behaviour in relation to having sex whilst imagining him- or her-self in the scenario. The scenario described unprotected sex between two individuals not in an existing relationship. Consistently across studies, intoxication had a significant effect on intentions for men but not for women. Also consistently across studies, affective attitudes were significantly stronger determinants of intentions for women than for men. Alcohol intoxication consistently moderated the impact of affective attitudes on intentions in women but not men, with greater intoxication associated with stronger impacts (Studies 1, 2, and 3). Implications for understanding the impacts of alcohol intoxication on sexual decision making in men and women are discussed.     

Numeracy as a Predictor of Adaptive Risky Decision Making

Numeracy or one's ability to appropriately process and use numerical information has been shown to be an important individual difference factor in decision making. The current study utilized a risky decision‐making task (called the “cups task”) in which choices are made to both earn and avoid losing hypothetical money. Critically, this design allowed investigators to examine numeracy‐related differences in adaptive decision‐making as measured by sensitivity to expected value (EV) differences over 54 paired‐choice trials—some in which it was advantageous to take a risk and some in which it was not. Results showed that in an undergraduate sample of 114 individuals, the less numerate took more risks and were less sensitive to varying EV levels than the more numerate, especially when it was disadvantageous to take a risk and when the choice involved a potential loss (rather than a gain). These results are consistent with a dual processing account in which the more numerate are much better than the less numerate at extracting the precise affective “gist” of the numerical information, which is then used to determine the goodness or badness of a particular choice. Copyright © 2012 John Wiley & Sons, Ltd.     

Revisiting the Gain–Loss Separability Assumption in Prospect Theory

A fundamental assumption of prospect theory is gain–loss separability (GLS)—the assertion that the overall utility of a prospect can be expressed as a function of the utilities of its positive and negative components. Violations of GLS may potentially limit the generalization of results from studies of single‐domain prospects to mixed prospects and systematically distort the predictions of the theory. Violations also have implications for how choices with positive and negative components should be presented to decision makers. Previous studies, using different elicitation methods, have documented different rates, and types, of systematic violations of GLS. We discuss the differences between two specific elicitation methods—binary choice and certainty equivalents—and report results of a new study of GLS using both methods and randomly generated prospects. We compare the extent and nature of GLS violations under the two elicitation methods using between‐subject and within‐subject analyses. We find (i) systematic violations of GLS under both methods, (ii) higher rates of violations under choice, (iii) higher sensitivity to the outcomes for the certainty equivalents, which is consistent with the predictions of the scale‐compatibility hypothesis, and (iv) different patterns of violations under the two methods, which are explained by method‐specific preferences. We discuss the psychological mechanisms underlying the findings and the implications for presenting information with gain and loss components. Copyright © 2012 John Wiley & Sons, Ltd.     

Strategy Selection in Risky Choice: The Impact of Numeracy,Affect, and Cross‐Cultural Differences

Real‐world decisions often involve options with outcomes that are uncertain and trigger strong affect (e.g., side effects of a drug). Previous work suggests that when choosing among affect‐rich risky prospects, people are rather insensitive to probability information, potentially compromising decision quality. We modeled the strategies of less and more numerate participants in the United States and in Germany when choosing between affect‐rich prospects and between monetarily equivalent affect‐poor prospects. Using large probabilistic national samples (n = 1047 from the United States and Germany), Study 1 showed that compared with more numerate participants, less numerate participants chose the normatively better option (i.e., the one with the higher expected value) less often, guessed more often, and relied more on a simple risk‐minimizing strategy. U.S. participants—although less numerate—selected the normatively better option more frequently and were more consistent across affect‐rich and affect‐poor problems than the German participants. Using a targeted quota sample (n = 118 from Germany), Study 2 indicated that although both more and less numerate participants paid less attention to probability information in affect‐rich than in affect‐poor problems, the two numeracy groups relied on different outcome‐based heuristics: More numerate participants often followed the minimax heuristic, and less numerate participants the affect heuristic. The observed strategy differences suggest that attempts to improve decision‐making need to take into account individual differences in numeracy as well as cultural‐specific experiences in making trade‐offs. Copyright © 2012 John Wiley & Sons, Ltd.     

Manipulating number generation: Loud + long = large?

Humans make numerous choices every day and tend to perceive these choices as free. The present study shows how simple free choices are biased by experiencing unrelated auditory information. In two experiments, participants categorized tones according to their intensity on the dimensions volume and duration on the majority of trials. On some trials, however, they were to randomly generate a number, and we found these choices to be influenced by tone intensity. Particularly, if participants were cued toward volume, loud tones clearly biased participants to generate larger numbers. For tone duration, a similar effect only emerged if spatial information was reinforced by the motor context of the task. The findings extend previous findings relating to the ATOM framework (A Theory of Magnitude) by an explicit focus on auditory magnitude processing. As such, they also constrain ATOM by showing that the connections between different magnitude dimensions vary to a considerable degree.