概率大小、损益结果和认知闭合需要对模糊规避的影响

模糊规避是指在相同奖赏的情况下,决策者会力图规避从主观上判断具有模糊概率的事件而偏好具有相同精确概率的事件。本研究探讨了概率大小、损益结果和认知闭合需要对模糊规避的影响。研究发现,在小概率受益的情况下,个体倾向于模糊寻求;在中概率受益的情况下,个体倾向于模糊规避;在高概率受益的情况下,个体倾向于模糊规避;在小概率损失的情况下,个体倾向于模糊规避;在中概率损失的情况下,个体倾向于模糊规避;在高概率损失的情况下,个体倾向于模糊寻求。但是,研究并未发现认知闭合需要对模糊规避有预测作用。     

Linguistic–Numeric Presentation Mode Effects on Risky Option Preferences

In this study, we examine preferences between lotteries with chances presented either numerically or linguistically. Presentation mode is predicted to affect preferences due to the perception of linguistic chance as skewed distributions of risk. Based upon weighting functions incorporating risk/uncertainty aversion from ambiguity theory and cumulative prospect theory, we predict that presentation mode effects on risky choices will be detectable in very small risks and in large risks. In two experiments, subjects chose between both gain and loss lotteries with constant payoffs and equivalent numeric and linguistic chances. Presentation mode affected choices when chances were above 50%, where lotteries with numeric chances were more frequently preferred in gains while lotteries with linguistic chances were more often preferred in losses. The effect of presentation mode for low-chance lotteries (5% and less) also affected choices such that numeric choices were generally preferred more frequently in losses and linguistically expressed choices were generally preferred more often in gains. Overall, these results suggest that theories of the effects of second order uncertainty on risky choice may be used to model decisions involving linguistic risk. They also suggest that the study of the perception of linguistic risk assessments can provide insight into the cognitive processing behind the weighting functions proposed to depict decision under risk and uncertainty. Finally, the results have practical implications since information providers can affect decision makers’ choices by controlling presentation mode in such a way as to alter the relative attractiveness of uncertain events.     

不确定性容忍度对模糊决策中决策偏好的影响及其情景依赖性*

研究以Ellsberg选瓶任务为决策材料,探讨了不同任务特征下个体不确定性容忍度对模糊决策中决策偏好的影响。结果发现,获益情景下:高概率时高、低容忍度个体对模糊选项的选择无显著差异,均偏好模糊规避;中概率时低容忍度个体比高容忍度个体表现出更低程度的模糊规避,前者倾向于模糊中立,后者倾向于模糊规避;低概率时两者对模糊选项的选择无显著差异,均倾向于模糊中立。损失情景下:高概率时两者对模糊选项的选择无显著差异,均倾向于模糊寻求;中概率时低容忍度比高容忍度个体更偏好模糊寻求,前者倾向于模糊寻求,后者倾向于模糊中立;低概率时两者对模糊选项的选择无显著差异,均倾向于模糊规避。这表明,不确定性容忍度对模糊决策偏好产生作用,但这种作用会受到损益概率和损益结果的影响,具有情景依赖性。     

行为决策中模糊规避研究的回顾与展望

模糊规避是指在相同奖赏的情况下,决策者会偏好有精确概率的事件而不是从主观上判断具有相同模糊概率的事件。自从Ellsberg提出模糊规避的概念以来,模糊规避已在行为决策研究的多个领域得到广泛验证。本文梳理了近五十年来关于模糊规避的研究文献,系统分析了模糊规避的研究范式、心理机制和影响因素,同时提出了未来的研究展望。     

概率水平与模糊性对短视损失规避的影响

短视损失规避是指如果投资者频繁地评估其投资回报,那么他就会经常改变其投资决策,进而减少对风险资产的投入。本文采用实验法探讨了任务概率水平以及模糊性对短视损失规避的影响。结果发现短视损失规避只存在于中等损失概率任务中,说明该现象并非普遍存在;当概率模糊时,高损失概率任务中出现短视损失规避,而低损失概率任务中则出现反向的短视损失规避,说明模糊性能扩展“短视”起作用的概率范围。     

The same but different: an empirical investigation of the reducibility principle

According to classical utility theory the valuation of any lottery should depend only on its outcomes and their respective probabilities, and should not be affected by the nature, complexity and structure of the chance mechanism. Previous research has documented systematic violations of this principle. For example, most subjects prefer lotteries in which the payoffs are contingent on the joint occurrence of multiple (high probability) events to simple lotteries, and lotteries in which the earlier stages offer higher probabilities than the later stages. We review the various violations of this principle and suggest a classification into two major types associated with misunderstanding of chance mechanisms and attitude towards the chance mechanism and process. In the present study 40 subjects were presented with 30 pairs of binary gambles. In any given pair the lotteries had identical outcomes and equal ‘reduced’ probabilities (and thus equal expected values). However, the chance mechanisms varied along a variety of factors such as the size of the sample space, the number of stages, temporal ordering, order of probabilities, their transparency and time constraints. Half the subjects saw lotteries involving gains and the other half considered only losses. After choosing one lottery in each pair, the subjects were asked to explain and justify their choices. The findings revealed systematic violations of the reducibility principle: subjects displayed a preference for lotteries with larger sample spaces, and for lotteries that allow quicker resolutions in the earlier stages. A clear distinction between some patterns of preferences in the gains and loss domains was revealed. In gambles involving gains subjects preferred to have the highest probability on the first stage (and the lowest probability on the last stage), but displayed the opposite preferences for losses. A content analysis of the subjects' stated reasons for their choices identified eight major categories. The most frequently invoked were hope, fun, simplicity, stress and time. Copyright © 2001 John Wiley & Sons, Ltd.     

Conflict Aversion: Preference for Ambiguity vs Conflict in Sources and Evidence

This research investigates preferences and judgments under ambiguous vs conflicting information. Three studies provided evidence for two major hypotheses: (1) Conflicting messages from two equally believable sources are dispreferred in general to two informatively equivalent, ambiguous, but agreeing messages from the same sources (i.e., conflict aversion); and (2) conflicting sources are perceived as less credible than ambiguous sources. Studies 2 and 3 yielded evidence for two framing effects. First, when the outcome was negative, subjects' preferences were nearly evenly split between conflict and ambiguity, whereas a positive outcome produced marked conflict aversion. Second, a high probability of a negative outcome or a low probability of a positive one induced conflict preference. However, no framing effects were found for source credibility judgments. Study 3 also investigated whether subject identification with a source might affect preferences or credibility judgments, but found no evi dence for such an effect. The findings suggest cognitive and moti vational explanations for conflict aversion as distinct from ambi guity aversion. The cognitive heuristic is that conflict raises suspicions about whether the sources are trustworthy or credi ble. The motivational explanation stems from that idea that if sources disagree, then the judge not only becomes uncertain but also must disagree with at least one of the sources, whereas if the sources agree then the judge may agree with them and only has to bear the uncertainty.     

On the composition of risk preference and belief

Prospect theory assumes nonadditive decision weights for preferences over risky gambles. Such decision weights generalize additive probabilities. This article proposes a decomposition of decision weights into a component reflecting risk attitude and a new component depending on belief. The decomposition is based on an observable preference condition and does not use other empirical primitives such as statements of judged probabilities. The preference condition is confirmed by most of the experimental findings in the literature. The implied properties of the belief component suggest that, besides the often-studied ambiguity aversion (a motivational factor reflecting a general aversion to unknown probabilities), perceptual and cognitive limitations play a role: It is harder to distinguish among various levels of likelihood, and to process them differently, when probabilities are unknown than when they are known.     

模糊规避的形成机制：基于可评价性假设的视角

模糊规避是指在相同奖赏的情况下,决策者会力图规避从主观上判断具有模糊概率的事件而偏好具有相同精确概率的事件。本研究使用同时评价、单独评价的研究范式从随机事件和自然事件两个领域来探讨模糊规避的形成机制。研究结果表明,当风险事件和模糊事件同时评价时,个体倾向于模糊规避;当风险事件和模糊事件单独评价时,模糊规避会消失。     

Good fortune but bad luck? Predictable versus unpredictable gains and losses in risky choice

This study examines the effects of two different types of good and bad experiences on risk‐taking preferences: fortune and luck. We define fortune as a relatively stable positive or negative context within which choices are made and luck as a more unpredictable series of better or worse outcomes. With the use of a lottery‐based paradigm, fortune was operationalized as a preponderance of all‐gain or all‐loss two‐outcome option pairs within a larger set of mixed‐outcome control lotteries. Luck was operationalized as the experienced frequency of better versus worse outcomes when playing the lotteries. We predicted that fortune and luck would lead to opposite risk‐taking tendencies within control lotteries. An assimilation effect of fortune was predicted, with risk‐averse preferences for control lotteries when surrounded by good fortune and risk‐seeking preferences when surrounded by bad fortune. In contrast, we expected that high rates of success with good luck would lead to risk‐seeking preferences, whereas low rates of success with bad luck would yield risk‐averse preferences. Our predictions for fortune were confirmed; however, there was no evidence of any effect on risk taking based on experiencing good versus bad luck. Moreover, we observed a striking disconnect between impressions of the experience and risk‐taking behavior. Both identification and attributions of luck and fortune were highly correlated with the number of gain outcomes that participants experienced but were uncorrelated with risk taking. We review these surprising findings considering several prominent theories of risk‐taking behavior, particularly drawing attention to the differential roles of predecisional and postdecisional information in choice.     

Impact of regulatory focus on ambiguity aversion

Although prior research has shown that some people prefer a risky to an ambiguous option, this study further proposes that people's regulatory focus (promotion vs. prevention) might influence their ambiguity aversion. Three experiments have tested whether people with promotion focus showed less ambiguity aversion than those with prevention focus: The first experiment revealed that, compared with chronically promotion‐focused individuals, prevention‐focused subjects preferred a risky to an ambiguous option. In the second experiment, priming of the subjects' goal orientations led to similar results. Experiment 3 demonstrated that participants showed less ambiguity aversion for the expected performance of an investment product representative of promotion (e.g., a stock fund) rather than one representative of prevention (e.g., a bond fund). In other words, people showed less preference for a bond fund when the probability distribution of its expected performance was unknown than when it was known, whereas they showed less preference difference between known and unknown probability distributions for the expected performance of a stock fund. This study has integrated research pertaining to regulatory focus and ambiguity aversion, and the results have confirmed that the impact of regulatory focus on ambiguity aversion is robust across different methods and decision tasks. Copyright © 2010 John Wiley & Sons, Ltd.     

Boundary effects of vague risk information on taxpayer decisions

In compliance decisions, the decision maker usually has only vague or ambiguous knowledge of the probability of being caught and the outcome (amount of penalty). An experiment is reported which extends work on effects of probability ambiguity by manipulating outcome ambiguity as well. When outcomes were limited to a bounded range and probabilities ranged between their natural boundaries [0, 1] in experimental tax decisions, symmetrical boundary effects were found in which vague estimates for both the probability and outcome dimensions caused vagueness aversion (and higher compliance) when the vague estimate was near the more favorable lower boundary of either dimension and vagueness seeking (and lower compliance) when the vague estimate was near the less favorable upper boundary. Probability and outcome vagueness effects were found to be independent of the vagueness of the other dimension, and vagueness effects were not systematically related to the level of the other dimension.The results suggest that a common cognitive process mediates the impact of vagueness on both dimensions. This may be a vagueness-adjustment process in which vague estimates are adjusted toward the middle of the bounded range, or a vagueness-preference process in which vague outcomes, and vague probabilities as well, are evaluated based on utility considerations, as though probability were a tangible commodity. For increasing compliance, the results suggest that risk information should be disseminated only when risks of punishment are relatively high. When risks are low, random enforcement techniques that enhance vagueness become more effective.     

Attributions for ambiguity in a treatment-decision context can create ambiguity aversion or seeking

The phenomenon of ambiguity aversion suggests that people prefer options that offer precisely rather than imprecisely known chances of success. However, past work on people's responses to ambiguity in health treatment contexts found ambiguity seeking rather than aversion. The present work addressed whether such findings reflected a broad tendency for ambiguity seeking in health treatment contexts or whether specific attributions for ambiguity play a substantial role. In three studies, people choose between two treatment options that involved similar underlying probabilities, except that the probabilities for one option involved ambiguity. The attributions offered for the ambiguity played an important role in the results. For example, when the range of probabilities associated with an ambiguous treatment was attributed to the fact that different studies yield different results, participants tended to show ambiguity aversion or indifference. However, when the range was attributed to something that participants could control (e.g., regular application of a cream) or something about which they were overoptimistic (e.g., their immune system function), participants tended to show ambiguity seeking. Health professionals should be mindful of how people will interpret and use information about ambiguity when choosing among treatments.     

Low- and high-testosterone individuals exhibit decreased aversion to economic risk

Testosterone is positively associated with risk-taking behavior in social domains (e.g., crime, physical aggression). However, the scant research linking testosterone to economic risk preferences presents inconsistent findings. We examined the relationship between endogenous testosterone and individuals' economic preferences (i.e., risk preference, ambiguity preference, and loss aversion) in a large sample (N = 298) of men and women. We found that endogenous testosterone levels have a significant U-shaped association with individuals' risk and ambiguity preferences, but not loss aversion. Specifically, individuals with low or high levels of testosterone (more than 1.5 SD from the mean for their gender) were risk and ambiguity neutral, whereas individuals with intermediate levels of testosterone were risk and ambiguity averse. This relationship was highly similar in men and women. In contrast to received wisdom regarding testosterone and risk, the present data provide the first robust evidence for a nonlinear association between economic preferences and levels of endogenous testosterone.     

The Effect of Temporal Distance on Attitudes toward Imprecise Probabilities and Imprecise Outcomes

Many personal, managerial, and societal decisions involve uncertain or ambiguous consequences that will occur in the future. Yet, previous empirical research on ambiguity preferences has focused mainly on decisions with immediate outcomes. To close this gap in the literature, this paper examines ambiguity attitudes toward future prospects, particularly how they may differ from the attitudes toward comparable prospects in the present. On the basis of a recent paradigm, we first distinguish between two types of ambiguity: imprecise probabilities and imprecise outcomes. Then, in accordance with construal level theory, which shows that temporal distance increases the relative importance of outcomes over probabilities in evaluating prospects, we conjecture that temporal distance would moderate attitudes toward imprecise probabilities but amplify attitudes toward imprecise outcomes. Through a series of experiments, we demonstrate that when the prospects are in the future, individuals are less averse toward imprecise probabilities and more seeking toward imprecise outcomes. However, the effect is most prominent for prospects where both the probability and outcome dimensions are concurrently imprecise. The paper ends with a discussion on how dimension salience may have contributed to this result. Copyright © 2012 John Wiley & Sons, Ltd.     

Does probability weighting matter in probability elicitation?

One of the most widely used methods for probability encoding in decision analysis uses binary comparisons (choices) between two lotteries: one that depends on the values of the random variable of interest and another that is contingent on an external reference chance device (typically a probability wheel). This note investigates the degree to which differences in probability weighting functions between the two types of events could affect the practice of subjective probability encoding. We develop a general methodology to investigate this question and illustrate it with two popular probability weighting functions over the range of parameters reported in the literature. We use this methodology to (a) alert decision analysts and researchers to the possibility of reversals, (b) identify the circumstances under which overt preferences for one lottery over the other are not affected by the weighting function, (c) document the magnitude of the differences between choices based on probabilities and their corresponding weighting functions, and (d) offer practical recommendations for probability elicitation.     

The priority heuristic: making choices without trade-offs

Bernoulli's framework of expected utility serves as a model for various psychological processes, including motivation, moral sense, attitudes, and decision making. To account for evidence at variance with expected utility, the authors generalize the framework of fast and frugal heuristics from inferences to preferences. The priority heuristic predicts (a) the Allais paradox, (b) risk aversion for gains if probabilities are high, (c) risk seeking for gains if probabilities are low (e.g., lottery tickets), (d) risk aversion for losses if probabilities are low (e.g., buying insurance), (e) risk seeking for losses if probabilities are high, (f) the certainty effect, (g) the possibility effect, and (h) intransitivities. The authors test how accurately the heuristic predicts people's choices, compared with previously proposed heuristics and 3 modifications of expected utility theory: security-potential/aspiration theory, transfer-of-attention-exchange model, and cumulative prospect theory.     

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     

The Rhythm Is Gonna Get You: The Influence of Circadian Rhythm Synchrony on Self‐Control Outcomes

This article aims to bridge the circadian and self‐control literatures by suggesting that people's self‐control performance varies as a function of their circadian preferences (i.e., chronotype). We review evidence for this assertion across a wide range of self‐control domains, including cognitive processing, emotion regulation, interpersonal relationships, and social influence. Across these widely ranging behaviors, the results indicate that when people's circadian preference matches the time of day, a synchrony effect occurs, and self‐control performance is at its peak. Therefore, people are more likely to display self‐regulatory failures and give in to temptations when there is a mismatch between their circadian preferences and time of day. Overall, this article offers new insights into the relationship between circadian preferences and self‐control and suggests novel and exciting new directions for future research.