Withdrawal Aversion and the Equivalence Test

If a doctor is trying to decide whether or not to provide a medical treatment, does it matter ethically whether that treatment has already been started? Health professionals sometimes find it harder to stop a treatment (withdraw) than to refrain from starting the treatment (withhold). But does that feeling correspond to an ethical difference? In this article, we defend equivalence—the view that withholding and withdrawal of treatment are ethically equivalent when all other factors are equal. We argue that preference for withholding over withdrawal could represent a form of cognitive bias—withdrawal aversion. Nevertheless, we consider whether there could be circumstances in which there is a moral difference. We identify four examples of conditional nonequivalence. Finally, we reflect on the moral significance of diverging intuitions and the implications for policy. We propose a set of practical strategies for helping to reduce bias in end-of-life decision making, including the equivalence test.     

Let It Go: Positive Affect Attenuates Sunk Cost Bias by Enhancing Cognitive Flexibility

Sunk cost bias is a pervasive problem in consumer decision making. It occurs when people continue to invest resources toward unsuccessful outcomes merely because they previously invested in them. This tendency exists because people devote too much attention to prior investments without considering how other factors may impact their decision outcome. While many suggested interventions to attenuate sunk cost bias involve altering cognitive processes, we examine an alternate affective route. Specifically, we propose that inducing positive affect attenuates sunk cost bias by naturally facilitating flexible thought processes. Across four studies, using hypothetical and real decision tasks, we find that positive affect induced in three different ways consistently attenuates sunk cost bias involving money, time, and effort investments. Further, we demonstrate that this occurs because people experiencing positive affect have enhanced cognitive flexibility. They consider more relevant decision factors and perceive sunk cost as having less of an influence on their decision outcomes. Then, in a fifth study, we show that a thought intervention promoting flexibility can attenuate consumers’ suboptimal commitment tendency in a field setting.     

Sunk Cost and Commitment to Medical Treatment

The influence of prior, irretrievable, investment (sunk cost) on commitment to medical treatment was investigated. Three studies were run investigating the influence of sunk cost in the form of money, time, and effort. A total of 637 participants (314 male) with a mean age of 19.58 years were recruited from an undergraduate population. A computer program simulated the process of arranging a course of physiotherapy. Participants invested one of three amounts of sunk cost (under budget, on budget, or over budget) into arranging sessions with a chiropractor. Participants then decided how much time they wished to commit to these chiropractor sessions or to an alternative treatment with a better chance of success. Results revealed a significant effect of invested money, a significant effect of invested effort, but no effect of invested time. Invested money produced a sunk cost effect, while invested effort appeared to exert influence via cognitive dissonance. The implications for healthcare decision-making are discussed.     

Sunk Cost and Commitment to Dates Arranged Online

The influence of prior, irretrievable, investment (sunk cost) on commitment to a date arranged online was investigated. Participants were recruited from an undergraduate population. There were 145 participants (86 female) with a mean age of 19.42 years. Participants took part in a computer simulation of the process of arranging a date online. Participants invested one of five amounts of sunk cost into this process. Participants were then presented with the choice of attending the date arranged online or attending a (superior) blind date. Participants chose how much time that they wanted to commit to the (inferior) date arranged online. Results revealed a significant sunk cost effect (p = 0.003). The implications of the sunk cost effect having an influence over human relationships are discussed.     

沉没成本效应中的心理学问题

沉没成本效应是一种常见的非理性行为。本文从心理学角度对其进行了系统地介绍。文章概括了沉没成本及沉没成本效应的定义,沉没成本的种类和发生领域,并用心理学理论对沉没成本效应进行了解释。此外．文章还讨论了沉没成本的逆效应以及影响沉没成本效应的主要因素。     

沉没成本效应的产生根源与影响因素

沉没成本效应是指决策者的决策行为因受沉没成本影响而产生的一种非理性决策现象。针对这一决策偏差的产生根源,研究者从认知、动机和神经三个角度提出了解释。沉没成本效应的影响因素包括沉没成本特性、情境因素、个体差异和文化差异等。基于先前研究存在的问题和不足,沉没成本效应的未来研究应着眼于改进研究方法,探究产生根源,关注行为沉没成本和加强应用研究。     

Sunk Cost,Emotion, and Commitment to Education

The influence of prior, irretrievable, investment (sunk cost) on commitment to a course of education was investigated. The moderating effects of the emotions of anger and fear over this commitment decision were also investigated. A total of 425 participants (214 male) with a mean age of 19.92 years were recruited from an undergraduate population. A computer program simulated the process of arranging to undertake a course of education. Participants were induced to feel either anger or fear and, then, invested one of three amounts of sunk cost (under budget, on budget, or over budget) to signing up for a course. Participants then decided how much time they wished to commit to this course or to an alternative, identical course with a better chance of success. Results revealed a significant sunk cost effect of prior investment on commitment to a course of education. Results also revealed that anger increased the magnitude of this sunk cost effect. Results did not reveal any effect of fear on the sunk cost effect. Theoretical implications and practical applications were discussed.     

关于成本沉没效应的实验研究

运用IAT 技术,通过实验,证明“损失厌恶”具有内隐性,“损失厌恶”存在内隐偏差,并且二者具有很强的稳定性,即不受当前情绪及刺激材料性质等的影响,为进一步认识成本沉没效应等现象的本质特点提供了证据。     

Sunk Cost Effects: The Influences of Instruction and Future Return Estimates

Normative principles imply that decision makers′ choices should be affected solely by the prospective future consequences of the options. Previous work, however, has demonstrated the occurrence of sunk cost effects, whereby decision makers are reluctant to abandon options in which they have made prior investments. The present research shows that, contrary to earlier findings, there exist conditions under which sunk cost effects are reduced significantly by instruction in pertinent economic principles. Additional findings indicate that sunk cost effects are mitigated by an important factor that is often present in real-world decision situations but omitted in most sunk cost research paradigms-explicit estimates of the future returns the given options might yield. Theoretical and practical implications are developed and discussed, including possibly common ambiguities about what normative sunk costs principles imply and how they should be applied.     

童年中后期儿童同伴接纳知觉准确性与偏差及其对社交退缩的影响

以小学三年级至六年级的儿童为被试,探讨同伴接纳知觉准确性的年级和性别差异,同时考察同伴接纳知觉准确性及偏差对社交退缩行为的预测作用。儿童完成同伴评定、知觉评定、社交自我知觉和班级戏剧量表。结果表明：（1）随着年级的升高,儿童的同伴接纳知觉越来越准确;儿童的同性同伴接纳知觉准确性不存在显著的性别差异;四年级男生的异性同伴接纳知觉准确性显著低于女生;（3）同伴接纳知觉准确性显著正向预测安静退缩和活跃退缩;同伴接纳知觉偏差显著负向预测安静退缩,但对活跃退缩不具有显著的预测效应。     

Loss Aversion and Foreign Policy Resolve

This article draws upon recent findings from the field of neuroscience to explore how loss aversion affects foreign policy resolve. We theorize that U.S. policy makers are more resolute in pursuing preventive policies that seek to avoid losses than they are in pursuing promotive policies that seek to acquire new gains. To test our theory, we conduct the first large‐n analysis of foreign policy hypotheses derived from the neuroscience of loss aversion using data from 100 cases of U.S.‐initiated Section 301 trade disputes. The results provide strong support for the loss‐aversion‐based theory, revealing that American policy makers are willing to fight harder and hold out longer in trade disputes with preventive objectives than they are in cases with promotive ones. Our study demonstrates that hypotheses derived from neuroscientific findings can be tested using large‐n techniques in study of foreign policy, revealing a new avenue of inquiry within the field.     

厌恶性条件反射与脑中c-fos的表达

Ｆｏｓ免疫组织化学法作为一种神经功能活动形态定位法,已在大鼠厌恶性条件反射的神经机制的研究中得到应用。无论是在味觉厌恶性条件反射的研究中,还是在听觉刺激与电击相结合的厌恶性条件反射的研究中,都证明了条件反射建立后,条件刺激能诱导出与非条件刺激相似的ｃ－ｆｏｓ表达的分布,这提示条件反射学习沟通了条件刺激和非条件刺激这两种不同刺激在大脑中的传导通路。     

Systematic Withdrawal

Although AGM theory contraction (Alchourrón et al., 1985; Alchourrón and Makinson, 1985) occupies a central position in the literature on belief change, there is one aspect about it that has created a fair amount of controversy. It involves the inclusion of the postulate known as Recovery. As a result, a number of alternatives to AGM theory contraction have been proposed that do not always satisfy the Recovery postulate (Levi, 1991, 1998; Hansson and Olsson, 1995; Fermé, 1998; Fermé and Rodriguez, 1998; Rott and Pagnucco, 1999). In this paper we present a new addition, systematic withdrawal, to the family of withdrawal operations, as they have become known. We define systematic withdrawal semantically, in terms of a set of preorders, and show that it can be characterised by a set of postulates. In a comparison of withdrawal operations we show that AGM contraction, systematic withdrawal and the severe withdrawal of Rott and Pagnucco (1999) are intimately connected by virtue of their definition in terms of sets of preorders. In a future paper it will be shown that this connection can be extended to include the epistemic entrenchment orderings of Gärdenfors (1988) and Gärdenfors and Makinson (1988) and the refined entrenchment orderings of Meyer et al. (2000).     

行为经济学中的损失规避

损失规避是指,人们总是强烈倾向于规避损失：一定数额的损失所引起的心理感受,其强烈程度约相当于两倍数额的获益感受。这种强烈的心理与行为倾向广泛存在于风险与非风险领域,在该两个领域中损失规避的研究范式也不同。损失规避常见于经济和消费等领域,可用于解释行为决策中有悖于规范化理论的诸多现象,如禀赋效应、现状偏差、股权溢价之迷和赢者的诅咒等。然而,损失规避的机制研究还存在许多尚未解决的问题,如损失规避的本质以及适用条件。今后的研究不仅要注重认知角度和情感依恋,还要结合认知过程来研究损失规避的性质和内在机制,以期帮助人们认识、预测及干预由损失规避造成的经济损失和非理性决策。     

损失规避的产生根源

损失规避是指由损失引发的负效用大于由等量收益引发的正效用的现象, 其产生根源能够从神经经济学和进化心理学两个方向进行解释。损失规避的脑机制分为两个系统：主观价值评价系统主要包括纹状体和前额皮层, 与主观价值的评估有关; 情绪唤醒系统主要包括杏仁核和脑岛, 与厌恶等消极情绪有关。在进化心理学的视角下, 通过回顾有关动物决策行为的研究来探索损失规避行为的进化历史, 并结合相关进化理论总结该行为产生的进化原因。未来可探索与行为损失规避相关的神经递质, 进一步研究损失规避的产生根源。     

The Sunk Costs Fallacy or Argument from Waste

This project tackles the problem of analyzing a specific form of reasoning called sunk costs in economics and argument from waste in argumentation theory. The project is to build a normative structure representing the form of the argument, and then to apply this normative structure to actual cases in which the sunk costs argument has been used. The method is partly structural and partly empirical. The empirical part is carried out through the analysis of case studies of the sunk costs argument found in business decision-making, as well as other areas like medical decision-making and everyday conversational argumentation. The structural part is carried out by using existing methods and techniques from argumentation theory, like argumentation schemes. The project has three especially significant findings. First, the sunk costs argument is not always fallacious, and in many cases it can be seen to be a rational precommitment strategy. Second, a formal model of argumentation, called practical reasoning, can be constructed that helps a rational critic to judge which sunk costs arguments are fallacious and which are not. Third, this formal model represents an alternative model of rationality to the cost-benefit model based on Bayesian calculation of probabilities. This alternative model is called the argumentation model, and it is based on interpersonal reasoning in dialogue as the model of rational thinking. This model in turn is based on the underlying notion of commitment in dialogue.