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.     

Ambiguity attitudes in qualitative contexts: The role of prior beliefs

Most studies of ambiguity aversion rely on experimental paradigms involving monetary bets. Thus, the extent to which ambiguity aversion occurs outside of such contexts is much less understood, particularly when the situation cannot easily be reduced to numerical terms. The present work seeks to understand whether people prefer to avoid ambiguous decisions in a variety of different qualitative domains (e.g., work, family, love, friendship, exercise, study, and health), and, if so, to determine the role played by prior beliefs in those domains. Across three studies, we presented participants with 24 vignettes and measured the degree to which they preferred risk to ambiguity in each. We also asked them for their prior probability estimates about the likely outcomes in the ambiguous events. Ambiguity aversion was observed in the vast majority of vignettes, but at different magnitudes. It was predicted by whether the vignette involved gain or loss as well as by people's prior beliefs; however, the heterogeneity between people meant that the role of prior beliefs was only evident in an individual-level analysis (i.e., not at the group level). Our results suggest that the desire to avoid ambiguity occurs in a wide variety of qualitative contexts but to different degrees for different people and may be partially driven by unfavorable prior estimates of the likely outcomes of the ambiguous events.     

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。     

Task formats and ambiguity aversion

This paper proposes that task format (choosing or rejecting) moderates the effect of ambiguity aversion. Specifically, an ambiguous option is more attractive in a choosing task than in a rejecting task compared with a risky option. The author performed three experiments to test the propositions. In the first experiment, participants showed less ambiguity aversion when they had to choose a preferred option (risky or ambiguous) compared with when they had to reject an option they preferred less. In the second experiment with a monetary incentive, participants had to form a cash‐equivalent estimate for both a risky gamble and an ambiguous gamble in a traditional Ellsberg scenario. The ambiguous option emerged as more attractive than the risky option in the choosing task compared with the rejecting task. The third experiment showed that the participants' decision rationale mediated the effect of the task format on choice. These three experiments support the proposition that task formats moderate the effect of ambiguity aversion. On the basis of the findings, the author provides suggestions for practice and further research. Copyright © 2010 John Wiley & Sons, Ltd.     

Size doesn't really matter: ambiguity aversion in Ellsberg urns with few balls

When attempting to draw a ball of a specified color either from an urn containing 50 red balls and 50 black balls or from an urn containing an unknown ratio of 100 red and black balls, a majority of decision makers prefer the known-risk urn, and this ambiguity aversion effect violates expected utility theory. In an experimental investigation of the effect of urn size on ambiguity aversion, 149 participants showed similar levels of aversion when choosing from urns containing 2, 10, or 100 balls. The occurrence of a substantial and significant ambiguity aversion effect even in the smallest urn suggests that influential theoretical interpretations of ambiguity aversion may need to be reconsidered.     

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。     

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。     

Is luck on my side? Optimism,pessimism, and ambiguity aversion

The influences of optimism and pessimism on ambiguity aversion were investigated in two tasks that manipulated the presence or absence of a potentially competitive experimenter. A total of 112 participants chose which option—ambiguous or known-risk—they preferred in the two slightly differing Ellsberg urns tasks. Optimism was measured using the Extended Life Orientation Test (ELOT). Highly optimistic people showed significantly less ambiguity aversion than less optimistic people when information was given that the number of balls was randomly determined. This pattern was present but less pronounced in the condition when the composition of the ambiguous urn could be interpreted as being influenced (rigged) by the experimenter. Pessimism was uninfluential. Perceptions of the situation, especially the degree of trust in the experimenter, were significantly influenced by the participants' optimism. People who do not have highly optimistic personalities tend to shy away from choosing ambiguous options. When ambiguity is clear, and trust issues are removed, people's optimistic outlook influences their degree of ambiguity aversion and thus their decisions.     

When and why do people avoid unknown probabilities in decisions under uncertainty? Testing some predictions from optimal foraging theory.

When given a choice between two otherwise equivalent options - one in which the probability information is stated and another in which it is missing - most people avoid the option with missing probability information (Camerer & Weber, 1992). This robust, frequently replicated tendency is known as the ambiguity effect. It is unclear, however, why the ambiguity effect occurs. Experiments 1 and 2, which separated effects of the comparison process from those related to missing probability information, demonstrate that the ambiguity effect is elicited by missing probabilities rather than by comparison of options. Experiments 3 and 4 test predictions drawn from the literature on behavioral ecology. It is suggested that choices between two options should reflect three parameters: (1) the need of the organism, (2) the mean expected outcome of each option; and (3) the variance associated with each option's outcome. It is hypothesized that unknown probabilities are avoided because they co-occur with high outcome variability. In Experiment 3 it was found that subjects systematically avoid options with high outcome variability regardless of whether probabilities are explicitly stated or not. In Experiment 4, we reversed the ambiguity effect: when participants' need was greater than the known option's expected mean outcome, subjects preferred the ambiguous (high variance) option. From these experiments we conclude that people do not generally avoid ambiguous options. Instead, they take into account expected outcome, outcome variability, and their need in order to arrive at a decision that is most likely to satisfy this need.     

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     

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。     

Ambivalence, discomfort, and motivated information processing

In two studies we examined the nature and consequence of ambivalent attitudes. In the first study, we assessed whether holding ambivalent attitudes was aversive, and tested whether this aversion was resolved through biased information processing. To do this we manipulated participants’ attributions of the discomfort associated with an ambivalent message through a pill manipulation (tense vs. relaxed). Participants who attributed their discomfort to their ambivalence reported more negative emotions and generated more one-sided thoughts than participants who attributed their discomfort to the pill. In the second study, we examined the conditions necessary for ambivalence reduction. Results suggest that people spontaneously engage in biased information processing in order to resolve their ambivalence.     

Misremembrance of options past: source monitoring and choice

This study reveals that when remembering past decisions, people engage in choice-supportive memory distortion. When asked to make memory attributions of options' features, participants made source-monitoring errors that supported their decisions. They tended to attribute, both correctly and incorrectly, more positive features to the option they had selected than to its competitor. In addition, they sometimes attributed, both correctly and incorrectly, more negative features to the nonselected option. This pattern of distortion may be beneficial to people's general well-being, reducing regret for options not taken. At the same time, it is problematic for memory accuracy, for accountability, and for learning from past experience.     

Visceral drives in retrospect: explanations about the inaccessible past

The present research demonstrates that the extent to which people appreciate the influence past visceral states have had on behavior (e.g., the influence hunger has had on food choice) depends largely on their current visceral state. Specifically, we found that when people were in a hot state (e.g., fatigued), they attributed behavior primarily to visceral influences, whereas when people were in a cold state (e.g., nonfatigued), they underestimated the influence of visceral drives and instead attributed behavior primarily to other, nonvisceral factors. This hot-cold empathy gap was observed when people made attributions about the past behavior of another person or themselves, and proved difficult to overcome, as participants could not correct for the biasing influence of their current visceral state when instructed to do so. These different attribution patterns also had consequences for people's satisfaction with their performance. Those who attributed their poor performance to visceral factors were more satisfied than those who made dispositional attributions.     

Effects of referential ambiguity,time constraints and addressee orientation on the production of morphologically complex words

In five experiments, participants were asked to describe unambiguously a target picture in a picture–picture paradigm. In the same-category condition, target (e.g., water bucket) and distractor picture (e.g., ice bucket) had identical names when their preferred, morphologically simple, name was used (e.g., bucket). The ensuing lexical ambiguity could be resolved by compound use (e.g., water bucket). Simple names sufficed as means of specification in other conditions, with distractors identical to the target, completely unrelated, or geometric figures. With standard timing parameters, participants produced mainly ambiguous answers in Experiment 1. An increase in available processing time hardly improved unambiguous responding (Experiment 2). A referential communication instruction (Experiment 3) increased the number of compound responses considerably, but morphologically simple answers still prevailed. Unambiguous responses outweighed ambiguous ones in Experiment 4, when timing parameters were further relaxed. Finally, the requirement to name both objects resulted in a nearly perfect ambiguity resolution (Experiment 5). Together, the results showed that speakers overcome lexical ambiguity only when time permits, when an addressee perspective is given and, most importantly, when their own speech overtly signals the ambiguity.     

Attributions to discrimination and self-esteem: Impact of group identification and situational ambiguity

This study examined group identification and situational ambiguity as moderators of attributions to discrimination and self-esteem following negative feedback. As predicted, high gender-identified women made more discrimination attributions than low identified women when situational prejudice cues were ambiguous, but not when prejudice cues were absent or overt. Also as predicted, women exposed to overt prejudice cues had higher self-esteem than those exposed to ambiguous cues or no prejudice cues. The relationship between discrimination attributions and self-esteem was positive among women exposed to overt prejudice but negative among those exposed to no prejudice. Across conditions, however, the more that women discounted ability as a cause of their negative feedback (i.e., blamed discrimination more than ability), the higher their self-esteem. Results qualify and extend prior research and demonstrate that personal and situational factors moderate both the tendency to make attributions to discrimination and the consequences of those attributions for self-esteem.     

Ambiguity seeking in multi-attribute decisions: Effects of optimism and message framing

This paper investigates the influence of message framing and personality variables on preferences over ambiguity in the context of multi-attribute decision scenarios. Undergraduate subjects responded to scenarios in which one of two medical treatments was associated with ambiguous probabilities of treatment effects. Probabilities were either positively or negatively framed. Subjects indicated their degree of preference for one treatment over the other. Subjects' optimism, trait anxiety, health locus of control, need for cognitive structure, and current mood were measured. In two separate studies, subjects preferred ambiguity when probabilities were positively framed, and were neutral toward ambiguity when probabilities were negatively framed. Also, in both studies the preference for ambiguity in positively framed scenarios was greater for more optimistic subjects. The unexpected finding of ambiguity seeking may be associated with the use of different decision strategies in multi-attribute versus single-attribute decisions.     

Couples’ Attributions for Work Function Changes in Prodromal Huntington Disease

People who have tested positive for the expanded Huntington disease (HD) gene who are not yet diagnosed (pre-HD) and their companions report subtle changes in ability of people with pre-HD to do their jobs. However, it is not known whether they attribute these changes to HD. Semi-structured telephone interviews were analyzed from seven persons with pre-HD at different estimated points from diagnosis and six companions. Data were analyzed using qualitative analysis methods. Participants made attributions related to health, work, and temperament. Only one participant attributed a change to HD. The process of forming attributions was demonstrated through symptom monitoring and comparison of participants with pre-HD to others with and without HD. Participants also expressed uncertainty regarding how to make attributions. Attributions influence coping procedures, including whether to seek and accept medical treatment. In persons with prodromal HD the relationship between attributions and use of coping strategies for symptoms that interfere with job functioning is unknown.