心理学报, 2019, 51(4): 395-406 doi: 10.3724/SP.J.1041.2019.00395

“以小拨大:行为决策助推社会发展”专栏

人非理性且难教化?论支持自由家长主义的证据

Gerd Gigerenzer1, 栾胜华,2, 刘永芳3

1 Max Planck Institute for Human Development, Berlin 14195, Germany

2 中国科学院心理研究所, 北京 100101

3 School of Psychology and Cognitive Science, East China Normal University, Shanghai 200062, China

Are we truly irrational and almost impossible to educate? Analyzing the scientific evidence behind libertine paternalism

Gerd GIGERENZER1, LUAN Shenghua,2, LIU Yongfang3

1 Max Planck Institute for Human Development, Germany

2 Institute of Psychology, Chinese Academy of Sciences, Beijing 100101, China

3 华东师范大学心理与认知科学学院, 上海 200062

通讯作者: 栾胜华, E-mail: luansh@psych.ac.cn

收稿日期: 2017-11-14   网络出版日期: 2019-04-25

Received: 2017-11-14   Online: 2019-04-25

摘要

基于心理学的研究, 自由家长主义者认为人们的思维有个体难以克服的、根深蒂固的系统性缺陷, 并难以通过教育来避免和消除, 因此主张因势利导, 仰仗外部专家的“助推”把人们的行为引导到正确方向。然而, 从生态理性的角度看, 人们依照自由家长主义者所谓的认知偏差做出的选择未必导致糟糕的结果, 而依照自由家长主义者所推崇的理性方法做出的选择也未必导致理想的结果。本文分析了自由家长主义者用来支持助推的证据后发现:(1)它们源于一些研究者对“何为理性”的狭隘定义, 误解了人类理性的本质; (2)它们对研究结果进行了选择性的报告, 忽视了与这些证据相反的证据。通过这些分析, 我们认为“人非理性且难教化”这一自由家长主义者的论断过于武断并有失偏颇。投入教育, 教会人们如何精明老练地处理风险不仅是可行的, 而且是替代助推的一个更为持久有效的解决方案。

关键词: 助推 ; 生态理性 ; 风险 ; 不确定性 ; 启发式 ; 框架效应 ; 概率学习

Abstract

Based on research in psychology, libertine paternalists argue that our mind is systematically flawed, which leads to many cognitive biases that are too deeply entrenched to eradicate through education. Thus, they suggest that authorities should take lead and nudge people into proper behaviors and good decisions. However, from the perspectives of ecological rationality, the outcomes of the so-called cognitive biases may not be bad, and in many instances, can be even better than those of the so-called rational reasoning as suggested by libertine paternalists. We analyze the evidence libertine paternalists use to justify nudging and find two major problems: (1) some of the supposed evidence is the product of researchers’ narrow interpretations of what qualify as human rationality and rational thinking; and (2) some libertine paternalists selectively reported scientific evidence, neglecting or sparsely reporting research that show findings contradictory to their belief. We conclude that there is lack of evidence to support the assertion that people are irrational and almost impossible to educate. To invest on education and make people risk savvy not only has been shown plausible and applicable, but also should be a more sustainable solution than nudging.

Keywords: nudge ; ecological rationality ; risk ; uncertainty ; heuristics ; framing effect ; probability learning

PDF (694KB) 元数据 多维度评价 相关文章 导出 EndNote| Ris| Bibtex  收藏本文

本文引用格式

Gerd Gigerenzer, 栾胜华, 刘永芳. (2019). 人非理性且难教化?论支持自由家长主义的证据. 心理学报, 51(4), 395-406

Gerd GIGERENZER, LUAN Shenghua, LIU Yongfang. (2019). Are we truly irrational and almost impossible to educate? Analyzing the scientific evidence behind libertine paternalism. Acta Psychologica Sinica, 51(4), 395-406

自由家长主义(libertarian paternalism)是一种社会管理理念, 主张管理机构应该像父母对待孩子一样善意地引导人们的选择和行为, 但同时也要给人们自由抉择的权利, 不强迫他们应该或不应该做什么, 其目标是保护民众, 帮助他们避免自身的推理错误、行为惰性和直觉导致的不良行为和错误决定。为达到此目的, 自由家长主义者主张用助推(nudging)的方式来引导人们的行为, 即不采用明显的奖惩机制来影响人们的决定, 也不通过强制性手段来胁迫某种行为的发生。

例如, 在许多国家年过50岁的女性会收到乳腺钼靶检查(mammography)的预约信。这种默认预约是一种利用我们行为惰性的助推——这些女性可能不会主动花精力去注册和预约, 但同样也不会花精力拒绝给定的预约。不仅如此, 在这些预约信件和附带的宣传册中常会提及早期钼靶检查可以使乳腺癌的死亡率降低20%, 这是利用多数人对统计信息一知半解的第二个助推。乳腺钼靶检查将1000个女性中因乳腺癌而死的人数(检查10年后)从5个降到4个, 相当于风险降低的绝对值是在1/1000。但为了彰显效果, 宣传数据中只给了一个风险降低20%的相对值(Gigerenzer, 2014a)。

这个例子很好地说明了助推和教育的区别。助推(比如预约信)旨在改变人们的行为(提高检查的参与率), 而非增进人们对检查本身的理解。结果是, 与没有被类似手段助推的俄罗斯女性相比, 欧盟国家的女性对于检查的好处知晓更少(Gigerenzer, Mata, & Frank, 2009)。相反, 教育的目的在于开启民智, 需要政府采用种种措施让公众理解风险信息, 并用透明的方式来传递信息, 以促使公众自己做出明智的决定。但这么做可能会导致与助推目标相反的行为:如果公众知道只有少数女性会从乳腺钼靶检查中受益而大多数会受损(包括检查所需的时间和金钱, 结果可能出现的假阳性, 以及知道结果后的心理负担, 等等), 很多女性可能就不愿意参加检查了。

本文的中心思想是:善意地针对人们的认知偏差因势利导、加以助推是可取的, 但并非是帮助人们的唯一途径。更为重要的是有意识地教育引导人们娴熟地应对和处理风险, 做出明智的决策。助推无可厚非, 但自由家长主义者将其唯一化和极端化的做法及其背后的证据是值得商榷的。

1 助推和自由家长主义

在研究文献中, 助推常常与自由家长主义混为一谈。在我们看来, 助推只是一个标签, 泛指那些非强制性的引导民众行为的方法。这些方法中有些在助推这个概念提出之前就早已存在, 比如在机场小便池上为减少尿液外溅而雕饰的黑苍蝇、芝加哥高速公路上为提醒司机减速而涂的条纹等(Norman, 1990)。但自从Thaler和Sunstein (2008)推出《助推》一书之后, 几乎所有影响人们行为的举措都被重新命名为助推, 这使得该概念变得过分空泛。关于自由家长主义, 我们采用Rebonato (2012)的定义:

自由家长主义是一系列的干预措施, 其方式是利用人们稳定的认知偏差来克服这些偏差本身, 而其目标是用以上方式引导人们做出他们自己所认同的理性选择。

其核心思想如下:

目标。一个善意的“选择建构师”为人们指定的最佳选择和行为。

操纵。在没有利诱、威逼或者教育的情况下, 选择建构师利用各种助推手段促使人的行为向定义的好的方向发展。

辩护。为了辩解为什么要助推而不是教育, 自由家长主义者们诉诸心理学研究, 声称这些研究指出人们系统性地缺乏理性并且无力摆脱他们的错误。

在以上三点中, 最后一点对自由家长主义者们尤其重要。Ariely (2008, p.xviii)总结道:“我们不仅是非理性的, 而且是可预见的非理性的”。这些非理性到底是什么呢?Thaler和Sunstein (2003)解释道:“人们对自己的行为没有理性的预期, 不能做出符合贝叶斯定理的预测, 使用了引导他们犯系统性错误的启发式, 表现出偏好反转, 以及仅仅因为措辞不同而对同一问题做出不同的选择” (p.176)。

基于此, Thaler和Sunstein诙谐地说, 人类远不是经济学家们所设想的那个精明的经济人(Homo economicus), 而更像是动画片辛普森一家中的那个傻老爹(Homer Simpson)。这个比喻及其隐含的思想影响甚广, 因为它直接戳中了新古典主义经济学和其他自由主义经济学的要害。例如, 在《反自制》一书中, 法律哲学家Sarah Conly指出, 著名的自由主义经济学家John Stuart Mill“未能像我们现在这样充分认识到人类心理在经济行为中的作用” (p.8), 以及“认知缺陷的存在确实表明需要不同类型的立法……包括强制性的家长式立法, 因为这样的法律可以迫使人们去做对他们自己有好处的事情” (p.2-3)。在《家长制和认知偏差》一文中, 哲学家J. D. Trout (2005)认为:“我们对于认知偏差的文献综述将表明它们几乎和肌肉反射一样稳定、持久和普遍” (p.396), 以及“启蒙运动中对人性的展望是个严重的误判”。同样, 行为经济学家Richard Thaler (1991)断言:“认知错觉应该被视为普遍规则而非个例” (p.4)。心理学家Daniel Kahneman (2011)也声称:“民主制度的混乱无可避免, 部分原因是影响公民想法和态度的可得性和情感启发式都不可避免地存在偏差, 即使它们所指引的方向在大多数情况下是正确的” (p.145)。

尽管这些言论措辞辛辣, 但其本意并非质疑和推翻“精明经济人”假说。相反, 自由家长主义者们毫无保留地接受决策论中的公理(axiom)作为理性行为的规范, 谴责和嘲讽普通公众无法达到这种理想行为。在他们看来, 用“智人” (Homo sapiens)一词来描述人类并不恰当, 表现在两方面:

人类缺乏理性。他们声称实验结果已经表明, 由于固有的认知局限性, 人类常为系统性的思维错误所困扰。

人类几乎无法被教化。他们主要通过类比而非实证推导出人类无法摆脱思维错误的结论。经常使用的三个类比是:视觉错觉, 爬行动物脑(即大脑中最原始的、自爬行动物就有的部分), 以及与生俱来的依赖于启发式和直觉而非统计和逻辑的“系统1”。这几个类比将认知错误和生物决定论画上等号, 暗示尝试教育人们摆脱这些错误是注定会失败的。

简而言之, 自由家长主义者们辩称认知缺陷既普遍又近乎不可根除。虽然他们没有明确表述后者, 但若缺少这一点, 他们就不得不解释一下为何相较于教育人们, 他们更推崇助推。在本文中, 我们将论证:

(1)有关人类系统性非理性的证据远非自由家长主义者们所宣称的那样清晰。具体而言, 他们的结论是基于:(a)狭义的以逻辑思维为本的理性标准, 误解了理性的生态适应性本质; (b)证实性偏差(confirmation bias), 即为了证明自己论断正确而选择性地引用证据。

(2)没有清晰的实证研究支持人们是不可被教育的。相反, 研究表明儿童、成人、专家都可以借助于适当的数字或者视觉表征来学习正确的统计思维。教育人们, 使得他们能精明老练地处理风险(risk savvy)是一种能替代助推的有效方式(Gigerenzer, 2014b)。

(3)自由家长主义的实施离不开那些对何为最优选择了如指掌的选择构架师。这就事先推定了这些人不会像我们一样受认知偏差的困扰, 同时也不会和我们有利益冲突。但是研究表明这样的专家和政策制定者很可能是不存在的。

2 关于人们系统性偏离理性的证据

在这里, 我们把分析限定在上文Thaler和Sunstein (2003, p.176)所引用的三个所谓的稳定认知错误上:

(1)人们会根据对问题的描述措辞而做出不同的选择, 即框架效应(framing effect)。

(2)人们无法做出符合贝叶斯定理的预测, 即基率谬误(base rate fallacy)。

(3)人们使用将他们引向系统性错误的启发式, 其潜在的假设是依靠统计学和逻辑所做出的判断总是比依靠启发式和直觉所做出的判断更加准确。

2.1 框架效应

当人们在两个所谓“逻辑上等同”的表述中做出不同选择时, 框架效应就会发生。框架效应被认为与理性行为不一致, 因为它违反了描述恒定性(description invariance)法则, 而该法则是“任何规范性(normative)决策理论的必要条件” (Tversky & Kahneman, 1986, p.S253)。框架效应对自由家长主义来说非常重要, 因为它意味着除了家长制之外别无选择:由于任何决策选项都需要用某种描述来呈现给做决定的人, 所以必须要有人站出来指出这个决定究竟应该如何来做(Thaler & Sunstein, 2008)。

我们并不认同逻辑等同或描述恒定性是理性行为普适性规范的观点。让我们从框架效应的经典示例说起:

水杯一半是满的(half full)。

水杯一半是空的(half empty)。

不同的描述会对人有影响吗?在一个实验中, 桌上放了一个装满水的杯子(A)和一个空杯(B)。实验者要求被试将A杯里的水倒一半至B杯中, 然后将那个“半空的”的杯子放到桌边。结果发现, 多数人选择了A杯(Sher & McKenzie, 2006)。这个和其他类似的实验表明, 许多情况下, 一个请求的具体表达方式会附带一些多余的信息。在这个实验里, 杯子的过去状态起到了参照点的作用, 使多数人直观地认为实验者所指的半空的杯子是那个被倒掉了一半水的杯子。仔细倾听和理解他人从而减少任务的不确定性是种能力, 它所表现出的是一种社交智慧, 而不是非理性偏差。对这个实验中的被试而言, 他们要做实用而非有逻辑的推论。更广泛地说, 对思维和环境(这里是听者和述者)之间关系的分析恰恰是生态理性的的体现(Gigerenzer & Selten, 2001), 而描述等同是逻辑理性的一种形式。作为规范性决策的准则, 逻辑理性并不能保证正确解读给出的信息。

下面是自由家长主义者们(Sunstein, 2013, p.61; Thaler & Sunstein, 2008, p.39)给出的一个框架效应的例子:假如你患有心脏病, 正在考虑是否接受一项有风险的心脏手术。医生用两种不同的方式来表述术后的效果:

术后五年, 90%的病人存活。

术后五年, 10%的病人死亡。

Thaler和Sunstein (2008)认为, 如果人们由于医生的不同表述方式而改变了选择, 就表明他们受到框架的影响而无法保持描述恒定性。仅引用了一项研究, 他们就断言在无数的实验中:“对于内容上完全一样的两个表述, 人们做出了完全不同的反应” (p.39), 然后总结道:“表述框架之所以起作用是因为人们时常是无意识的、被动的决策者” (p.40)。

在一篇涉及40项研究的综述文章中(Moxey, O’Connell, McGettigan, & Henry, 2003), 作者发现看到存活表述的被试确实比看到死亡表述的被试更可能接受手术。但这种框架效应只有在手术治疗这种特定条件下才会发生。如果将治疗方式换成药物或免疫治疗, 就没有证据表明存在上述的框架效应。对真实而非假设情境决策行为的研究得到了同样的结果。

不妨让我们用分析“半满/半空”杯子问题相同的方法来分析“生存/死亡”表述框架问题, 不是孤立地考虑逻辑结构, 而是考虑病人的目的。无论是术后90%的存活率还是10%的死亡率都无法为病人决策提供充分的信息, 因为病人不知道不做手术的存活率或死亡率。虽然这是决定手术与否的重要参照点, 但该信息没有出现在问题表述中。因此, 病人不得不依赖他们的社交智慧来做出明智的猜测。如前所述, 语言描述具有生态效应, 述者可以选择表述方式传递关于参照点的信息, 而听者也会捕捉到这些信息。实验显示, 如果参照点低一些(不做手术的病人存活率较低), 那么80%~94%的医生会选择用生存表述框架和病人沟通; 但如果参照点高一些(不做手术的病人存活率较高), 那么生存表述框架就少有人选择了(McKenzie & Nelson, 2003)。因此, 通过选择表述框架, 医生可以传达何种治疗方案更好的信息, 从而给出暗示性的建议, 而接受医生建议也是病人的应选之项, 并非所谓的认知偏差。

最后, 让我们讨论一下那个鼎鼎有名的亚洲疾病问题(Tversky & Kahneman, 1981)。一种疾病预计会致死600人, 被试需要在两种治疗方案中做出选择。对方案有正面和负面两种表述框架, 正面(亦称获益)的表述是:

如果接受方案A, 200人将会得救(无风险选项)。

如果接受方案B, 1/3的可能性600人将获救, 2/3的可能性无人获救(有风险选项)。

负面(亦称损失)的表述是:

如果接受方案C, 400人将会死亡(无风险选项)。

如果接受方案D, 1/3可能性无人死亡, 2/3的可能性600人死亡(有风险选项)。

与之前的两项任务相比, 这个任务中增加了一个风险选项。许多实验表明, 当在获益框架下选择时, 多数人倾向于无风险选项A; 但当在损失框架下选择时, 多数人倾向于有风险选项D。因为正面表述在逻辑上等同于负面表述, 这一结果让大多数人的选择看起来逻辑不一致。

然而, 仔细推敲这个问题中的措辞, 你会发现一个奇怪的地方:风险选项的结果是完整给定的, 而无风险选项则不是。例如, 无风险选项说“200人将会获救”, 但没有加上“400人将不会获救”。从逻辑上说, 缺失的信息对获益和损失两种表述框架的整体结构没有影响, 但对于聪明人来说, 缺失信息是有意义的。不给出完整信息或许正是框架效应产生的原因, 也是自由家长主义者完成“助推”的关键点。回顾一下上面的那个手术问题, 你会发现亚洲病问题中的两个无风险选项对应于手术问题中的“生存/死亡”表述框架, 二者对被试的暗示作用具有异曲同工之妙。与此种生态(而非逻辑性的)分析相一致的是, 研究表明亚洲病问题中的框架效应主要是由无风险选项而非风险选项所导致的(Kühberger & Gradl, 2013)。当研究者详述了无风险选项时, 亚洲病问题上的框架效应就消失了(Kühberger, 1995; Kühberger & Tanner, 2010; Mandel, 2001)。这表明, 人们倾向于假设选项的表述方式会泄露表述者的意图, 包含隐晦的暗示或推荐信息, 并依此做出选择。一旦把信息里的不确定因素解释清楚了, 框架效应就会消失。

上面关于框架效应的生态分析并非适用于所有框架效应。即便如此, 这些分析已足以证明描述恒定性并非总是评估理性行为的合理尺度。框架效应被认为违反了描述恒定性法则, 但其产生的原因可能是策略性互动、暗示推荐选项及其他形式的社交智慧。从生态理性的角度看, 述者常常需要依靠表述方式来隐晦地传递相关讯息和做出推荐, 而听者也需要捕捉这些信息, 并按照这种信息做出选择。事实上, 理解言外之意比遵循描述恒定性这样的逻辑法则对认知的要求更高。毕竟, 电脑可以毫不费力地掌握逻辑规则, 却还无法很好地理解自然语言。这些行为是人们追随直觉的结果, 却往往被曲解为逻辑谬误。当直觉比逻辑让人们更加聪明时, 还有必要助推他们脱离所谓的“逻辑谬误”吗?

我们不吝笔墨地介绍质疑描述恒定性逻辑规范的研究, 是因为这些研究很少被自由家长主义者们所注意或者被他们有意忽视。这种现象可以被称为“偏差研究的偏差”:只是关注和呈现那些看起来证明自己观点(即人们系统地偏离理性)的证据, 而忽略那些未发现偏差或对自己使用的理性标准持异见的研究。例如, 据我们所知, McKenzie团队关于框架效应的研究从未在自由家长主义者的文章中被提及, 也未见于大多数论及框架效应违反理性的行为经济学文章中。这一偏差在对其他所谓的认知错觉的研究中也存在(e.g., Gigerenzer, Fiedler, & Olsson, 2012; Gigerenzer, 2000)。下面让我们给出最后一个例子。

“行为心理学最重要以及最无可辩驳的发现之一就是人们对自己的判断过分自信” (Parikh, 2009, p. 142; Yu & Li, 2006)。类似的绝对性言论时有发生, 显示出这些人对“过分自信” (over confidence)现象的过分自信。然而, 稍微仔细地浏览一下相关的心理学文献, 你就会发现展现在你面前的是一幅相当不同的画面。首先, 有几个可能互有关联的现象都被贴上了过分自信的标签。先说“主观概率的校准误差”这一被称为无可辩驳的发现。自1990年代中期之后, 研究已经表明所谓的校准误差并非来自大众本身的系统性误差, 而是一个由研究者们的误解而产生的人为统计性误差, 即研究者错把一个非系统性误差当成了系统性误差(详见Dawes & Mulford, 1996; Erev, Wallsten, & Budescu, 1994)。其根本原因是常见的对“均值回归” (regression to the mean)这一统计现象的误解, 即错误地把不完美相关所导致的结果归因于系统性现象。同样的错误也出现在经典的所谓证明了人们系统性地高估小风险但低估大风险的研究中(Slovic, Fischhoff, & Lichtenstein, 1982)。之前及目前的研究表明, 产生这一校准误差的主要原因同样是均值回归这个统计现象, 而非被试的系统性偏差(Hertwig, Pachur, & Kurzenhäuser, 2005)。第二个也被称为过分自信的现象来自如下实验:被试回答一些问题, 将他们对答案的平均自信值减去他们最终的正确率后显示被试过分自信。研究表明这一结果可能源于研究者对问题的非代表性(即选择性)抽样。一份对于130个研究的元分析显示, 当进行代表性抽样时, 此种过分自信现象就消失了(Juslin, Winman, & Olsson, 2000)。

这些研究并非是说人们从来不会或不要过分自信。如果你从事通过预测汇率或者股票走势来赚钱的行业, 你通常都会、也需要过分自信, 否则你的建议不会有人买单。但是功能性的过分自信不同于人们与生俱来的认知错觉。在自由家长主义者的文章中, 我们没有看到有关多数人有非系统性(而不是系统性)偏差的研究的讨论, 也鲜有对不赞成他们观点的相关文献的引证。

2.2 贝叶斯定理

Thaler和Sunstein (2008)认为人们“无法做出符合贝叶斯定理的预测”。这个论断可以追溯到Kahneman和Tversky (1972), 他们拒斥了更早的认为人们是近似的但偏保守的贝叶斯思考者的结论:“从其对证据评估的结果来看, 人类显然不是保守的贝叶斯思考者, 而是与贝叶斯思考毫不沾边” (p.450)。与前述的描述恒定性不同, 贝叶斯定理是在一系列概率公理之上严格推论的产物。因此, 它是一个对人类理性的真正考验。在自由家长主义者看来, 如果应用贝叶斯定理的条件均已满足, 但人们的预测系统性地偏离这个定理, 而且无法从自己的错误中学习, 那么就是他们行为达不到理性标准的一个绝佳例证。在这里, 我们无法综述关于贝叶斯推理的浩繁的心理学文献, 只是简要指出与自由家长主义者们的结论截然不同的一些研究。

研究贝叶斯推理问题有两种范式:概率学习和文本问题。在概率学习中, 人们从经验中学习概率, 接着测试他们的判断是否符合贝叶斯定理。采用这种范式研究的许多认知科学家得出的结论是:人们的判断大致上与贝叶斯定理一致(e.g., Chater, Tenenbaum, & Yuille, 2006; Chater & Oaksford, 2008; Edwards, 1968)。例如, Schooler和Anderson (1997)的研究发现遗忘的原理与贝叶斯推理相符。在“贝叶斯认知模型”一文中, Griffiths, Kemp和Tenenbaum (2008)认为, 无论是无意识的低级知觉过程(如推断物体的颜色和形状), 还是高级认知过程(如语言的理解和分类), 都符合贝叶斯模型。在神经科学中, 假设人有一个“贝叶斯脑” (Friston, 2010)的思想影响颇广。行为经济学家总是宣称, 快速、无意识及自动的判断(所谓的系统1)不符合概率法则, 但以上所提到的认知科学家对此持相反看法。

研究贝叶斯推理的第二个范式是提供给被试一些文本问题, 其中的概率都是以数字呈现的。在这个范式中有两类问题。在第一类里, 只是提供有关基率(base rate)的数字, 如面试人中有30个工程师和70个律师, 然后被试看到对其中某一个人的描述, 如一个具有典型的工程师特征的人。平均下来, 人们估计这个人是工程师的可能性与工程师和律师的基率无关(Kahneman & Tversky, 1973)。这个以及类似的结果被认为是基率谬误的实例, “可能是我们的直觉偏离规范预测理论最明显的例子之一” (p.243)。

然而, 正如每位专业的统计学家都知道的那样, 理性地应用贝叶斯定理要求除将数字输入公式之外更多的东西, 包括检验定理所需的许多前提假设。关于基率在贝叶斯计算中作用的一个关键假设是, 那个被描述的人是从给定的人口中随机抽取的。如果不是, 我们就不能假设关于他的推断与基率具有相关性。尽管如此, 一些文本问题, 包括著名的“Tom W.” (Kahneman & Tversky, 1973)问题, 并没有给出是否随机抽样的任何信息。其他问题, 如上面的工程师-律师问题, 虽然声称有随机抽样, 但事实并非如此, 因为给被试的描述是编造的, 而不是真正随机抽样的结果(Gigerenzer, 2000, 第12章)。在工程师-律师实验中, 如果被试事先被告知箱子里每张卡片对一个人的描述与他们的身份是一致的, 并可以从箱子里随机抽出一个描述的话, 那么他们在很大程度上就不会忽视基率了(Baratgin & Noveck, 2000; Gigerenzer, Hell, & Blank, 1988)。因此, 普通人可能比那些指控他们非理性的研究者们对随机抽样这个概念更加敏感。

在第二个类型的文本问题中, 研究者不仅提供基率, 还提供击中率(hit rate)及误报率(false alarm rate), 要求被试估计后验概率; 出租车问题(Tversky & Kahneman, 1980)即为一例。与Thaler和Sunstein的论断一致, 在这项任务中, 有稳定的证据表明人们无法做出符合贝叶斯定理的预测。但是产生这一现象需要一个重要的附加条件:概率(如击中率和误报率)是以条件概率的方式呈现的。人们无法做出符合贝叶斯定理预测的原因不仅仅在于人们的思维, 也在于所给问题的生态环境, 即信息是如何呈现的。多数人都不擅长处理条件概率。

如果给被试的信息是自然频数(natural frequency), 那么能够按照贝叶斯定理进行推理的人的比例就会大幅上升(e.g., Brase, 2009; Gigerenzer & Hoffrage, 1995; Hoffrage, Lindsey, Hertwig, & Gigerenzer, 2000; Kleiter, 1994)。这对专业和非专业人士都是适用的。例如, 基于条件概率, 在得知一名女性乳腺钼靶检查呈阳性的情况下, 160名妇科医生中只有21%的人能准确地推断出她患有乳腺癌的后验概率。还是这些妇科医生, 在学习了如何将条件概率转换成自然频数之后, 87%的人可以推断出与贝叶斯定理相符的后验概率(Gigerenzer et al., 2007)。一份Cochrane系统评论(Aki et al., 2011)也认为, 相对于概率而言, 卫生领域的从业者和消费者更容易理解自然频数。自然频数同样可以帮助法官、律师及学习法律的学生理解DNA匹配意味着什么(e.g., Lindsey, Hertwig, & Gigerenzer, 2003; Hoffrage et al., 2000), 特别是当使用图形来表征频数的时候(e.g., Cosmides & Tooby, 1996; Spiegelhalter, Pearson, & Short, 2011)。

纵观完整的心理学文献, 人们普遍无法按照贝叶斯方式推理的论断是得不到证据支持的。相反, 生态分析显示, 某些信息呈现方式(如自然频数)能够帮助人们按照贝叶斯方式推理, 另一些则起干扰作用, 就像用阿拉伯数字比用罗马数字更有助于解决除法问题一样。此外, 前文提及的认知科学研究显示快速的、直觉的推理符合贝叶斯定理, 这些研究驳斥了认为无意识的、基础的心理过程不遵循概率原则这一所谓系统1的观点。

最后, 人们果真如把认知错觉类比为视觉错觉所暗示的那样无可教化吗?对妇科医生的研究给出了否定的答案:仅通过一节课的学习, 多数医生可以按照贝叶斯方式进行推理。但是, 人们可以将学到的东西保持下去吗?一个题为“两小时教会贝叶斯推理”的研究(Sedlmeier & Gigerenzer, 2001)显示, 训练被试用自然频数来解决问题的三个月后, 他们没有出现通常的遗忘迹象, 但教他们学习如何将概率嵌入贝叶斯公式进行计算时, 遗忘则会出现。另外, 即使是儿童也可以做出符合贝叶斯定理的预测。在北京进行的一项研究中, 135个儿童被问了1000多个以自然频数表述的贝叶斯问题。多数六年级的儿童可以准确地推断出贝叶斯后验概率, 五年级的1/3可以, 四年级的1/6可以(Zhu & Gigerenzer, 2006)。毫不奇怪, 当信息以条件概率的方式呈现时, 没有一个孩子可以解决任何一个问题。在同时使用自然频数和图标时, 德国四年级的儿童可以解决60%的贝叶斯问题, 甚至二年级的儿童也可以解决22%的问题(e.g., Gigerenzer, 2014b; Multmeier, 2012; Till, 2014)。自然频数如今在德国学校的数学课程中被教授, 它的使用也受到了一些重要的、尊重实证的医学社团的推荐, 例如International Patient Decision Aid Standards Collaboration和Healthcare Products Regulatory Agency, 即英国的食品与药物管理局。

总而言之, 没有证据支持人们不擅长贝叶斯式思维而且几乎无法摆脱自身偏差这一论断。

2.3 启发式

启发式在自由家长主义的论点中扮演了重要角色, 被认为是思维偏差产生的主要原因。人们“使用会将他们引向系统性失误的启发式” (Thaler & Sunstein, 2008, p.176)。依其所言, 人们只有通过依靠逻辑或统计学方法而非启发式才会做出最优的选择。然而, 只有在面对风险(risk)而非不确定性(uncertainty)的情况下, 逻辑和统计学方法才能定义什么是最优(e.g., Binmore, 2007; Knight, 1921)。“风险”指的是那些所有选项及其可能后果和概率都已知的情境, 例如那些教科书式的贝叶斯问题或者是赌场中的轮盘赌局; 在这些情境中, 可以计算出长期的预期损失, 不需要启发式的介入。“不确定性”指的是真实世界的情境, 例如涉及投资和医疗健康等方面的决策; 在这些情境中, 并非万事已知且意外时有发生, 因而没有办法界定何为最优。在不确定性的情况下, 适当应用那些寻求稳健(robust)而非最优解的启发式是可以帮人们做出理性决定的。对于现代贝叶斯优化理论之父Savage (1954)来说, 即使是计划一次野餐出行都在贝叶斯理论应用的范畴之外。那些断言启发式只是次优方法的行为经济学家忽视了风险和不确定性的重要区别。

举例而言, Thaler和Sunstein (2008, p.133-136) 报告说Harry Markowitz在投资自己的退休账户时, 使用的不是那个为他拿诺贝尔奖的均值方差组合法(mean-variance portfolio), 而是1/N的启发式。这个简单的启发式将可支配的资产在N个期权和股票中平均分配, 无需估测均值方差组合法中所需的许多参数。DeMiguel, Garlappi和Uppal (2009)测试了1/N启发式在股票市场的表现。依据包括夏普比率在内的评判标准, 在7个投资问题中, 有6个1/N的表现优于所谓“最优的”均值方差组合法。因此, 在这些不确定的情境中, 进行优化计算很可能意味着亏损。

其实, 是否应用启发式是个生态理性问题:我们应该探索在哪些环境中启发式比其他方法更准确。例如, 当市场高度不稳定、选项数目巨大、样本量很小几种情况下, 1/N可能会比Markowitz优化组合有更好的表现。这样的分析也有助于解释将1/N和均值方差组合法进行比较时发现的不一致结果(Brodie, Daubechies, de Mol, Giannone, & Loris, 2009)。关于生态理性的研究在Gigerenzer, Todd和the ABC Research Group (1999), Gigerenzer, Hertwig和Pachur (2011), 还有Gigerenzer和Selten (2001)这三本书中有详细的介绍和描述。简而言之, 生态理性的研究是那些建立在数学分析的基础上, 对Herbert Simon的剪刀类比(即我们的认知系统和环境如何一起产生理性行为)细致分析的研究; 在Luan, Schooler和Gigerenzer (2011, 2014)的研究中可找到这一研究范式的两个实例。Kahneman和Tversky常说启发式有时好有时坏, 但他们从来没有进一步明确“有时”到底是什么时候。而生态理性研究直面这一问题, 并拒斥了统计优化总是强于启发式这一过分简单的论断。

最后, 行为经济学家普遍认为, 人们违背理性公理的行为(如当他们依赖启发式时)为家长制提供了理论基础, 因为个体的偏差会导致集体(如市场)效率的降低, 而家长制对此有所帮助。然而, Berg和Gigerenzer (2007)在数理上证明这一观点是错误的。人的有限理性不意味着我们一定要求助于家长制。

3 关于人们难以教化的论点

如前文所述, 这一论点是隐晦地通过以下三个类比得出的:将认知错觉比作稳定的视觉错觉、爬行动物脑以及那个号称进化史上古老的、“不易教化”的系统1 (Kahneman, 2011, p. 417)。进化生物学家Stephen Jay Gould (1992)同样认为“我们的思维不是用来(不论何因)按照概率的法则工作的” (p.469)。自然杂志关于助推亦或教育的一篇文章中引用了Richard Thaler的话:“我们帮助人们消除偏差的能力是非常有限的” (Bond, 2009, p.1191)。因此, 这篇文章中又引用法学家Dan Kahan的话:“风险决策应该在更大程度上集中到不受政治影响的专家机构(p.1189-1190)”。

对此, 我们有两个回应。首先, 让我们看一下无法明确什么是最优行为的不确定性情境。在这里, 比起逻辑, 人们如能考虑到表述框架所隐含的信息或灵活地使用启发式, 他们的决定和行为将会更明智一些。所以, 没有理由教人们放弃自己的直觉智慧而去做那些逻辑上合理但实际效果欠佳的事情。其次, 考虑一下风险情境。在这里, 统计思维是合理的, 但人们却无法按照统计法则进行推理。此种情况下, 人们可以学习, 但需要辅助合适的工具, 如自然频数。Fong, Kantz和Nisbett (1986)向成年人和新泽西郊区的高中生们教授了大数定律(law of larger numbers)。经过只有25分钟的训练后, 被试们对日常问题的推理能力有了显著提高。与此类似, Nisbett (2009)介绍了一些如何通过训练来提升智商的方法。如同每一个参加统计学教学会议的人所体会到的那样, 传授统计思维是一个能帮助人们克服自身缺陷的可行方案。

真正能替代助推的是教育。教育的目的是让儿童和成人们可以精明老练地处理风险, 具有使用统计兼启发式思维的能力, 还要有能力去判断这两种思维方式各自的局限和应用范畴。遗憾的是, 多数国家没有教授孩子们涉及不确定性的数学, 而只是教他们几何和三角几何之类的涉及确定性的数学。

教育不在自由家长主义者们的考虑范围之内。他们将认知错误比作稳定的、不可避免的视觉错觉, 因此忽视教育并非偶然, 甚至是坚信这个类比正确的必然后果。但是, 这种观点忽略了一个事实, 那就是教育和健康行为紧密相关。例如, 过度肥胖在未受过多少教育的人中更加普遍。再考虑一下最可怕的疾病之一 ——癌症。如我们所见, 即便癌症筛查仅能帮助很少人延长生命而且使人在各种不必要的活检和手术中受到伤害, 人们还是被助推去做筛查(Welch, 2004)。由于约半数癌症都是由吸烟、肥胖、缺乏运动以及饮酒这样的行为引起的, 所以教育会是一个更好的与癌症斗争的武器。为了使教育更加有效, 我们应当在孩子们养成不健康饮食、饮酒和吸烟习惯之前就早早教育他们。比起癌症筛查和抗癌药物, 长远的教育计划(包括教导儿童如何烹饪, 享受健康的饮食, 以及教会他们如何看穿企业想方设法引诱他们走向不健康行为的企图等)或许可以拯救更多的生命(Gigerenzer, 2014a, b)。

4 关于善意选择构建师的假设

将人们助推到最佳选择要求有知道最佳选择的选择构建师。但是, 这个要求却包含了一个难于解决的矛盾(Berg & Gigerenzer, 2010; Rebonato, 2012):一方面, 专家们被认为与普通人一样会犯相同的认知偏差, 另一方面, 他们又被要求保持理性, 清楚人们真实的所需所求。举例而言, 尽管Thaler和Sunstein开玩笑称他们自己也是偏差的牺牲品, 但他们依然笔耕不辍, 表现得像是未被偏差所干扰一样。此外, 理想的、充满智慧的选择构建师们不仅要清晰洞察人们真实的所需所好, 还需要:

1)不进行防御性决策(defensive decision making);

2)理解科学证据;

3)与大众无利益冲突。

让我们看一下医疗保健, 一个自由家长主义者们认为政府、医院和医生应当将人们助推到恰当行为的领域。只有当以上三个条件都满足时, 助推才能使患者受益。但是, 在美国、德国和其他西方国家, 这些条件往往无法满足(Gigerenzer & Muir Gray, 2011)。

(1)自我防御。许多医疗从业者会采取防御性治疗; 也就是说, 为了保护自己不会受到潜在的诉讼, 他们不会推荐他们认为对患者来说最好的方案, 而会建议次之的方案。例如, 一项对美国宾州824名医生的研究发现, 93%的医生承认采取了防御性治疗, 包括给患者施加不必要的CT扫描、抗生素以及创伤性手术(Studdert et al., 2005)。

(2)数盲。许多医疗从业者不知道如何解读与健康有关的统计数字。例如, 在美国的家庭医生中, 有70%到80%的人不理解癌症筛查对患者的生存率意味着什么, 因此即使筛查所带来的伤害超过其益处, 他们也很容易被误导, 进而推荐病人做筛查(Wegwarth, Schwartz, Woloshin, Gaissmaier, & Gigerenzer, 2012)。

(3)利益冲突。一些医疗从业者会追求增加自身利益而非对病人最优的方案。这种情况可以看作成一个委托代理问题(principle-agent problem):代理方(医生、医院)会出于自身而非委托方(患者)的利益来采取行动。例如, 每年估计有一百万的美国儿童接受了不必要的CT扫描(Brenner & Hall, 2007)。CT扫描是医疗机构收入的重要来源, 但它将一个儿童暴露在相当于百次胸部X光扫描的辐射之中。据估计, 在美国每年有29000个癌症病例是由大约7000万的CT扫描导致的, 而且这个数字还在增加(de González et al., 2009)。

这三项偏差在医疗健康研究中被称为“SIC综合症”【即自我防御(Self-defense)、数盲(Innumeracy)和利益冲突(Conflicts of interest); Gigerenzer, 2014b)】。只要这个综合症存在, 选择构建师们就可能会将公众引向不符合公众最优利益的方向。以下是几个例子。

自我乳房检查。一些选择构建师认为, 那些不进行每月自我乳房检查的女性是偏风险规避的, 因此建议使用损失而非获益的表述框架来助推她们进行检查; 另一个助推的技巧是告诉女性, 与她们同龄的其他大多数女性都进行自我检查(e.g., Myerowitz & Chaiken, 1987; Salovay & Williams- Piehota, 2004)。但是, 随机临床试验并未发现自我检查能降低乳腺癌死亡率的证据, 相反, 有证据表明它会带来伤害, 例如增加了对乳房活体检查的次数(Kösters & Gøtzsche, 2003)。直到今天, 许多女性被引导进行自我乳房检查, 却没有被告知未有科学证据证明此举有益。另外, 如上文所述, 一些卫生机构通过发送预约邀请的方式助推女性去参加乳腺癌筛查, 但却不提及一项重要研究的结果:通过对超过50万女性进行的随机临床试验, Gøtzsche和Jørgensen (2013)未能发现乳腺癌筛查利大于弊的证据。在这里, 助推更像是为乳腺检查这一庞大行业的利益来服务, 而不是确保女性们做出更明智的决定。

H1N1疫苗。2009年, 随着猪流感的大爆发, 许多国家政府按照世界卫生组织的推荐, 购买了达菲之类的流感疫苗和药物。鉴于有些国家的疫苗接种率比较低, Sunstein (2013, p.59)建议用助推来提高人们的响应程度, 例如发给人们去地方疫苗接种中心的路线地图。当疫苗或者药物确实减少了死亡及严重并发症时, 这样的助推确实会带来帮助。但是, 在达菲这个案例中, 数年后仍未有它有效的证据。尽管英国医学杂志(British Medical Journal)多次要求达菲的制造商罗氏公布相关数据, 但却遭到罗氏的拒绝(该杂志在其网站上发表了与罗氏关于此事的信件交流)。为什么在没有任何证据的情况下, 世界卫生组织却鼓励政府大量储备抗病毒药物呢?答案看起来是利益冲突:许多为世界卫生组织建言的专家都跟生产这些药物的制药公司有经济联系(Cohen & Carter, 2010)。在这种情况下, 助推帮助制药行业赚得盆满钵盈, 而让助推者和被助推者为此买单。

PSA测试。Sunstein (2005)提出:“医生可将选项以特定框架来描述, 从而引领人们选择明显最好的医疗方案, 即使这个方案微小的失败可能性或许会吓退一些患者, 让他们去选择前景更差的方案。” (p. 180)。如果医院与患者没有利益冲突, 这会是一个有用的助推。不幸的是, 利益冲突经常存在, 医院会追求与患者完全相背的目标。例如, 许多医院推荐男性做常规PSA前列腺癌筛查, 尽管美国国家癌症研究所提出警告说PSA检测造成的伤害可能会大于其好处。通过在广告中歪曲统计数字, 著名的美国MD Anderson癌症中心在前列腺癌检测的好处上对男性进行了系统性的误导, 这与红丝带组织的Susan G. Komen在乳腺癌筛查上欺骗女性的行径如出一辙(详见Woloshin & Schwartz, 2012; Woloshin, Schwartz, & Welch, 2008)。如达菲案例中一样, 通往科学医学证据的道路总是被洪水般歪曲的信息所阻隔。例如, 一份基于9个国家代表性样本的研究显示, 超过90%的欧洲人高估了PSA和乳腺钼靶检查的好处(高估了10倍、100倍、甚至200倍)或者不知道它们到底是什么(Gigerenzer et al., 2009)。这并非是因为众多的欧洲人不能理性思维, 而是歪曲的统计数字将他们助推到盲信筛查的境地。

如果选择构建师将公众福祉放在心上, 那么助推或许是有效的。但是, 当政策制定者做防御性决策、是风险信息盲或者与大众有利益冲突(即有SIC综合征)时, 助推远非是个理想的选择。

5 结论:更多能精明老练处理风险的民众, 更少的助推

在本文中, 我们分析了被用来为助推辩护的科学证据。自由家长主义者声称这些证据清楚地表明人们的判断会系统性地偏离理性, 而且教育人们摆脱这些偏差即使不是不可能, 也是非常困难的。我们着重讨论了三个所谓的非理性认知偏差:框架效应、基率谬误以及对启发式的应用。我们的结论是, 要助推而不要教育的论断过分依赖于狭义的逻辑理性规范, 且有证真性偏差之嫌。对这三个“偏差”中的每一个来说, 偏离理性的情况都言过其实, 而且也少有证据表明人们是无法教育的。

知道这些之后我们应该怎么做呢?如前所述, 代替责怪和助推人们的更为有效的方式是教育他们在处理风险时精明老练。这要求人们同时具有统计思维和启发式思维的能力, 并且能意识到前者适用于风险情境, 而后者在不确定性情境中不可或缺。在日常生活的大部分问题里, 一部分的风险是已知的, 而其它部分则是未知的, 这就意味着这两种思维工具缺一不可。

自由家长主义者们认为没有别的治世方针可以替代他们所提倡的。但是, 如果当权政府因受其他利益所左右而停止助推怎么办?如果烟草和快餐业通过巨大投入将人们向相反的方向助推呢?助推的同时又不教育人们意味着把公众当做小孩来对待。这类行为的不良后果在人类社会进入数字化时代的今天尤其明显。从2009年起, 谷歌开始对搜索结果个性化。自此之后, 当两个人进行同样的搜索时, 他们再也不会看到同样的结果了。通过提供个性化的结果排序, 搜索引擎让我们看到我们喜欢看到的以及我们之前已经浏览过的网页。排序能影响我们的阅读内容, 其原理之一是约90%的搜索后点击都发生在搜索结果第一页上, 而三分之一的点击发生在第一条结果上。有证据表明, 如果操纵对竞选候选人的搜索结果排序, 民主选举的结果可能会受到影响(Epstein & Robertson, 2015)。这使对助推的讨论有了一个新的政治维度。

授人以鱼不如授人以渔。我们承认某些情况下自由家长主义者所倡导的助推是有用的策略, 但对比助推, 一个更加持续可行的方案是将资源投资到教人们如何能精明老练地处理风险。为了更有效, 教育应该提早, 最好在年青人被诱惑到吸烟、吃垃圾食物以及其它不健康行为之前就开始。通过教育, 让自己可以正确解读健康、金融和媒体报道中的风险和不确定性, 正在成为让我们在日益复杂的世界中生存的一项必不可少的技能。

参考文献

Aki E. A., Oxman A. D., Herrin J., Vist G. E., Terrenato I., Sperati F., … Schünemann H . ( 2011).

Using alternative statistical formats for presenting risks and risk reductions

Cochrane Database of Systematic Reviews, 3, CD006776.

URL     PMID:21412897      [本文引用: 1]

The success of evidence-based practice depends on the clear and effective communication of statistical information. To evaluate the effects of using alternative statistical presentations of the same risks and risk reductions on understanding, perception, persuasiveness and behaviour of health professionals, policy makers, and consumers. We searched Ovid MEDLINE (1966 to October 2007), EMBASE (1980 to October 2007), PsycLIT (1887 to October 2007), and the Cochrane Central Register of Controlled Trials (The Cochrane Library, 2007, Issue 3). We reviewed the reference lists of relevant articles, and contacted experts in the field. We included randomized and non-randomized controlled parallel and cross-over studies. We focused on four comparisons: a comparison of statistical presentations of a risk (eg frequencies versus probabilities) and three comparisons of statistical presentation of risk reduction: relative risk reduction (RRR) versus absolute risk reduction (ARR), RRR versus number needed to treat (NNT), and ARR versus NNT. Two authors independently selected studies for inclusion, extracted data, and assessed risk of bias. We contacted investigators to obtain missing information. We graded the quality of evidence for each outcome using the GRADE approach. We standardized the outcome effects using adjusted standardized mean difference (SMD). We included 35 studies reporting 83 comparisons. None of the studies involved policy makers. Participants (health professionals and consumers) understood natural frequencies better than probabilities (SMD 0.69 (95% confidence interval (CI) 0.45 to 0.93)). Compared with ARR, RRR had little or no difference in understanding (SMD 0.02 (95% CI -0.39 to 0.43)) but was perceived to be larger (SMD 0.41 (95% CI 0.03 to 0.79)) and more persuasive (SMD 0.66 (95% CI 0.51 to 0.81)). Compared with NNT, RRR was better understood (SMD 0.73 (95% CI 0.43 to 1.04)), was perceived to be larger (SMD 1.15 (95% CI 0.80 to 1.50)) and was more persuasive (SMD 0.65 (95% CI 0.51 to 0.80)). Compared with NNT, ARR was better understood (SMD 0.42 (95% CI 0.12 to 0.71)), was perceived to be larger (SMD 0.79 (95% CI 0.43 to 1.15)).There was little or no difference for persuasiveness (SMD 0.05 (95% CI -0.04 to 0.15)). The sensitivity analyses including only high quality comparisons showed consistent results for persuasiveness for all three comparisons. Overall there were no differences between health professionals and consumers. The overall quality of evidence was rated down to moderate because of the use of surrogate outcomes and/or heterogeneity. None of the comparisons assessed behaviourbehaviour. Natural frequencies are probably better understood than probabilities. Relative risk reduction (RRR), compared with absolute risk reduction (ARR) and number needed to treat (NNT), may be perceived to be larger and is more likely to be persuasive. However, it is uncertain whether presenting RRR is likely to help people make decisions most consistent with their own values and, in fact, it could lead to misinterpretation. More research is needed to further explore this question.

Ariely,D. ( 2008).

Predictably irrational: The hidden forces that shape our decisions.

New York:Harper Collins.

[本文引用: 1]

Baratgin, J., & Noveck, I. A . ( 2000).

Not only base rates are neglected in the Engineer-Lawyer problem: An investigation of reasoners' underutilization of complementarity

Memory & Cognition, 28, 79-91.

URL     PMID:10714141      [本文引用: 1]

The standard Engineer-Lawyer problem (Kahneman & Tversky, 1973) points to the failure of reasoners to integrate mentioned base-rate information in arriving at likelihood estimates. Research in this area nevertheless has presupposed that participants respect complementarity (i.e., participants ensure that competing estimates add up to 100%). A survey of the literature leads us to doubt this presupposition. We propose that the participants鈥 non-normative performance on the standard Engineer- Lawyer problem reflects a reluctance to view the task probabilistically and that normative responses become more prominent as probabilistic aspects of the task do. In the present experiments, we manipulated two kinds of probabilistic cues and determined the extent to which (1) base rates were integrated and (2) the complementarity constraint was respected. In Experiment 1, six versions of an Engineer-Lawyer-type problem (that varied three levels of cue to complementarity and two base rates) were presented. The results showed that base-rate integration increased as cues to complementarity did. Experiment 2 confirmed that Gigerenzer, Hell, and Blank鈥檚 (1988) random-draw paradigm facilitates base-rate integration; a second measure revealed that it also prompts respect for complementarity. In Experiment 3, we replicated two of our main findings in one procedure while controlling for the potential influence of extraneous task features. We discuss approaches that describe how probabilistic cues might prompt normative responding.

Berg, N., & Gigerenzer G. , (2007).

Psychology implies paternalism? Bounded rationality may reduce the rationale to regulate risk-taking

Social Choice and Welfare, 28, 337-359.

URL     [本文引用: 1]

Behavioral economists increasingly argue that violations of rationality axioms provide a new rationale for paternalism - to "de-bias" individuals who exhibit errors, biases and other allegedly pathological psychological regularities associated with Tversky and Kahneman's (in Science 185:1124-1131,1974) heuristics-and-biases program. The argument is flawed, however, in neglecting to distinguish aggregate from individual rationality. The aggregate consequences of departures from normative decision-making axioms may be Pareto-inferior or superior. Without a well-specified theory of aggregation, individual-level biases do not necessarily imply losses in efficiency. This paper considers the problem of using a social-welfare function to decide whether to regulate risk-taking behavior in a population whose individual-level behavior may or may not be consistent with expected utility maximization. According to the social-welfare objective, unregulated aggregate risk distributions resulting from non-maximizing behavior are often more acceptable (i.e., lead to a weaker rationale for paternalism) than population distributions generated by behavior that conforms to the standard axioms. Thus, psychological theories that depart from axiomatic decision-making norms do not necessarily strengthen the case for paternalism, and conformity with such norms is generally not an appropriate policy-making objective in itself.

Berg, N., & Gigerenzer G. , ( 2010).

As-if behavioral economics: Neoclassical economics in disguise?

History of Economic Ideas, 18, 133-165.

URL     [本文引用: 1]

For a research program that counts improved empirical realism among its primary goals, it is surprising that behavioral economics appears indistinguishable from neoclassical economics in its reliance on “as-if” arguments. “As-if” arguments are frequently put forward in behavioral economics to justify “psychological” models that add new parameters to fit decision outcome data rather than specifying more realistic or empirically supported psychological processes that genuinely explain these data. Another striking similarity is that both behavioral and neoclassical research programs refer to a common set of axiomatic norms without subjecting them to empirical investigation. Notably missing is investigation of whether people who deviate from axiomatic rationality face economically significant losses. Despite producing prolific documentation of deviations from neoclassical norms, behavioral economics has produced almost no evidence that deviations are correlated with lower earnings, lower happiness, impaired health, inaccurate beliefs, or shorter lives. We argue for an alternative non-axiomatic approach to normative analysis focused on veridical descriptions of decision process and a matching principle – between behavioral strategies and the environments in which they are used – referred to as ecological rationality. To make behavioral economics, or psychology and economics, a more rigorously empirical science will require less effort spent extending “as-if” utility theory to account for biases and deviations, and substantially more careful observation of successful decision makers in their respective domains.

Berrington de González A., Mahesh M., Kim K. P., Bhargavan M., Lewis R., Mettler F., & Land C . ( 2009).

Projected cancer risks from computed tomographic scans performed in the United States in 2007

Archives of Internal Medicine, 169, 2071-2077.

URL     [本文引用: 1]

Binmore, K . (2007).

Rational decisions in large worlds

Annales d'Ecomonie et de Statistique, 86, 25-41.

URL     [本文引用: 1]

No abstract is available for this item.

Bond, M . (2009).

Risk school

Nature, 461, 1189-1192.

URL     [本文引用: 1]

Brase, G.L . ( 2009).

Pictorial representations in statistical reasoning

Applied Cognitive Psychology, 23, 369-381.

URL     [本文引用: 1]

Brenner, D. J., & Hall, E. J . ( 2007).

Computed tomography— An increasing source of radiation exposure

New England Journal of Medicine, 357, 2277-2284.

URL     [本文引用: 1]

Brodie J., Daubechies I., de Mol C., Giannone D., & Loris I . ( 2009).

Sparse and stable Markowitz portfolios

Proceedings of the National Academy of Sciences of the United States of America, 106, 12267-12272.

URL     PMID:19617537      [本文引用: 1]

We consider the problem of portfolio selection within the classical Markowitz mean-variance framework, reformulated as a constrained least-squares regression problem. We propose to add to the objective function a penalty proportional to the sum of the absolute values of the portfolio weights. This penalty regularizes (stabilizes) the optimization problem, encourages sparse portfolios (i.e., portfolios with only few active positions), and allows accounting for transaction costs. Our approach recovers as special cases the no-short-positions portfolios, but does allow for short positions in limited number. We implement this methodology on two benchmark data sets constructed by Fama and French. Using only a modest amount of training data, we construct portfolios whose out-of-sample performance, as measured by Sharpe ratio, is consistently and significantly better than that of the naive evenly weighted portfolio.

Chater N. ,& Oaksford, M .( 2008). The probabilistic mind:Prospects for Bayesian cognitive science Oxford, United Kingdom: Oxford University Press.

[本文引用: 1]

Chater N., Tenenbaum J. B., & Yuille A . ( 2006).

Probabilistic models of cognition: Conceptual foundations

Trends in Cognitive Sciences, 10, 287-291.

URL     PMID:16807064      [本文引用: 1]

Remarkable progress in the mathematics and computer science of probability has led to a revolution in the scope of probabilistic models. In particular, ‘sophisticated’ probabilistic methods apply to structured relational systems such as graphs and grammars, of immediate relevance to the cognitive sciences. This Special Issue outlines progress in this rapidly developing field, which provides a potentially unifying perspective across a wide range of domains and levels of explanation. Here, we introduce the historical and conceptual foundations of the approach, explore how the approach relates to studies of explicit probabilistic reasoning, and give a brief overview of the field as it stands today.

Cohen, D., &Carter, P. ( 2010).

WHO and the pandemic flu “conspiracies.”

BMJ, 340, 1274-1279.

[本文引用: 1]

Cosmides, L., &Tooby, J. ( 1996).

Are humans good intuitive statisticians after all? Rethinking some conclusions from the literature on judgment under uncertainty

Cognition, 58, 1-73.

URL     [本文引用: 1]

Professional probabilists have long argued over what probability means, with, for example, Bayesians arguing that probabilities refer to subjective degrees of confi- dence and frequentists arguing that probabilities refer to the frequencies of events in the world. Recently, Gigerenzer and his colleagues have argued that these same distinctions are made by untutored subjects, and that, for many domains, the human mind represents probabilistic information as frequencies. We analyze several reasons why, from an ecological and evolutionary perspective, certain classes of problem- solving mechanisms in the human mind should be expected to represent probabilistic information as frequencies. Then, using a problem famous in the "heuristics and biases" literature for eliciting base rate neglect, we show that correct Bayesian reasoning can be elicited in 76% of subjects- indeed, 92% in the most ecologically valid condition- simply by expressing the problem in frequentist terms. This result adds to the growing body of literature showing that frequentist representations cause various cognitive biases to disappear, including overconfidence, the conjunction fallacy, and base-rate neglect. Taken together, these new findings indicate that the conclusion most common in the literature on judgment under uncertainty- that our inductive reasoning mechanisms do not embody a calculus of probability - will have to be re-examined. From an ecological and evolutionary perspective, humans may turn out to be good intuitive statisticians after all.

Dawes, R. M.,& Mulford, M. , ( 1996).

The false consensus effect and overconfidence: Flaws in judgment or flaws in how we study judgment

Organizational Behavior and Human Decision Processes, 65, 201-211.

URL     [本文引用: 1]

ABSTRACT Thefalse consensus effectand theoverconfidence in judgmenteffect are often referred to as established “facts” of psychology. At present, the empirical support for these effects is inadequate and logically flawed. We argue that, absent other information, using one's own response to a situation as an observation of size 1 could be an effective use of data and could lead to anincreasein the accuracy of predicting others’ behavior. In an empirical examination of such use, we find a robustpositivecorrelation between the degree to which people believe that a majority of others are like them and their accuracy in predicting those others’ responses, whether this correlation is evaluated within items across people, across items within people, or across items across people. In addition, we show that the finding of overconfidence in judgment follows analytically from the functional relationship used to demonstrate it, a “finding” that is easily reversed by considering the inverse relationship. Specifically, we argue that regression effects account for the evidence cited in support of overconfidence. While not definitive, our empirical findings call into the question the acceptance of these two effects—as commonly defined—as facts.

DeMiguel V., Garlappi L., & Uppal R . ( 2009).

Optimal versus naive diversification: How inefficient is the 1/ N portfolio strategy

Review of Financial Studies, 22, 1915-1953.

URL     [本文引用: 1]

We evaluate the out-of-sample performance of the sample-based mean-variance model, and its extensions designed to reduce estimation error, relative to the naive 1-N portfolio. Of the 14 models we evaluate across seven empirical datasets, none is consistently better than the 1-N rule in terms of Sharpe ratio, certainty-equivalent return, or turnover, which indicates that, out of sample, the gain from optimal diversification is more than offset by estimation error. Based on parameters calibrated to the US equity market, our analytical results and simulations show that the estimation window needed for the sample-based mean-variance strategy and its extensions to outperform the 1-N benchmark is around 3000 months for a portfolio with 25 assets and about 6000 months for a portfolio with 50 assets. This suggests that there are still many "miles to go" before the gains promised by optimal portfolio choice can actually be realized out of sample. The Author 2007. Published by Oxford University Press on behalf of The Society for Financial Studies. All rights reserved. For Permissions, please email: journals.permissions@oxfordjournals.org, Oxford University Press.

Edwards,W. ( 1968).

Conservatism in human information processing

In B. Kleinmuntz (Ed.), Formal representation of human judgment(pp. 17-52). New York: Wiley.

[本文引用: 1]

Epstein, R., & Robertson, R. E . ( 2015).

The search engine manipulation effect (SEME) and its possible impact on the outcomes of elections

Proceedings of the National Academy of Sciences of the United States of America, 112, E4512-E4521.

URL     PMID:26243876      [本文引用: 1]

Internet search rankings have a significant impact on consumer choices, mainly because users trust and choose higher-ranked results more than lower-ranked results. Given the apparent power of search rankings, we asked whether they could be manipulated to alter the preferences of undecided voters in democratic elections. Here we report the results of five relevant double-blind, randomized controlled experiments, using a total of 4,556 undecided voters representing diverse demographic characteristics of the voting populations of the United States and India. The fifth experiment is especially notable in that it was conducted with eligible voters throughout India in the midst of India's 2014 Lok Sabha elections just before the final votes were cast. The results of these experiments demonstrate that (i) biased search rankings can shift the voting preferences of undecided voters by 20% or more, (ii) the shift can be much higher in some demographic groups, and (iii) search ranking bias can be masked so that people show no awareness of the manipulation. We call this type of influence, which might be applicable to a variety of attitudes and beliefs, the search engine manipulation effect. Given that many elections are won by small margins, our results suggest that a search engine company has the power to influence the results of a substantial number of elections with impunity. The impact of such manipulations would be especially large in countries dominated by a single search engine company.

Erev I., Wallsten T. S., & Budescu D. V . ( 1994).

Simultaneous over- and underconfidence: The role of error in judgment processes

Psychological Review, 101, 519-527.

URL     [本文引用: 1]

ABSTRACT Two empirical judgment phenomena appear to contradict each other. In the revision-of-opinion literature, subjective probability (SP) judgments have been analyzed as a function of objective probability (OP) and generally have been found to be conservative, that is, to represent underconfidence. In the calibration literature, analyses of OP (operationalized as relative frequency correct) as a function of SP have led to the opposite conclusion, that judgment is generally overconfident. Reanalysis of 3 studies shows that both results can be obtained from the same set of data, depending on the method of analysis. The simultaneous effects are then generated and factors influencing them are explored by means of a model that instantiates a very general theory of how SP estimates arise from true judgments perturbed by random error. Theoretical and practical implications of the work are discussed. (PsycINFO Database Record (c) 2012 APA, all rights reserved)

Fong G. T., Krantz D. H., & Nisbett R. E . ( 1986).

The effects of statistical training on thinking about everyday problems

Cognitive Psychology, 18, 253-292.

URL     [本文引用: 1]

Friston,K . ( 2010).

The free-energy principle: A unified brain theory?

Nature Reviews Neuroscience, 11, 127-138.

URL     PMID:20068583      [本文引用: 1]

A free-energy principle has been proposed recently that accounts for action, perception and learning. This Review looks at some key brain theories in the biological (for example, neural Darwinism) and physical (for example, information theory and optimal control theory) sciences from the free-energy perspective. Crucially, one key theme runs through each of these theories - optimization. Furthermore, if we look closely at what is optimized, the same quantity keeps emerging, namely value (expected reward, expected utility) or its complement, surprise (prediction error, expected cost). This is the quantity that is optimized under the free-energy principle, which suggests that several global brain theories might be unified within a free-energy framework.

Gigerenzer, G. ( 2000). Adaptive thinking: Rationality in the real world. New York: Oxford University Press.

[本文引用: 2]

Gigerenzer,G. ( 2014a ).

Breast cancer screening pamphlets mislead women

BMJ, 348, g2636.

URL     PMID:24770369      [本文引用: 2]

All women and women’s organisations should tear up the pink ribbons and campaign for honest information

Gigerenzer,G. ( 2014b ).

Risk savvy: How to make good decisions

New York: Viking.

[本文引用: 3]

Gigerenzer G., Fiedler K.,& Olsson, H. , ( 2012) . Rethinking cognitive biases as environmental consequences. In P. M. Todd, G. Gigerenzer, & the ABC Research Group (Eds.), Ecological rationality: Intelligence in the world (pp. 80-110). New York: Oxford University Press.

[本文引用: 2]

Gigerenzer G., Gaissmaier W., Kurz-Milcke E., Schwartz L. M., & Woloshin S . ( 2007).

Helping doctors and patients to make sense of health statistics

Psychological Science in the Public Interest, 8, 53-96.

URL     PMID:26161749     

SUMMARY Many doctors, patients, journalists, and politicians alike do not understand what health statistics mean or draw wrong conclusions without noticing. Collective statistical illiteracy refers to the widespread inability to understand the meaning of numbers. For instance, many citizens are unaware that higher survival rates with cancer screening do not imply longer life, or that the statement that mammography screening reduces the risk of dying from breast cancer by 25% in fact means that 1 less woman out of 1,000 will die of the disease. We provide evidence that statistical illiteracy (a) is common to patients, journalists, and physicians; (b) is created by nontransparent framing of information that is sometimes an unintentional result of lack of understanding but can also be a result of intentional efforts to manipulate or persuade people; and (c) can have serious consequences for health. The causes of statistical illiteracy should not be attributed to cognitive biases alone, but to the emotional nature of the doctor patient relationship and conflicts of interest in the healthcare system. The classic doctor patient relation is based on (the physician's) paternalism and (the patient's) trust in authority, which make statistical literacy seem unnecessary; so does the traditional combination of determinism (physicians who seek causes, not chances) and the illusion of certainty (patients who seek certainty when there is none). We show that information pamphlets, Web sites, leaflets distributed to doctors by the pharmaceutical industry, and even medical journals often report evidence in nontransparent forms that suggest big benefits of featured interventions and small harms. Without understanding the numbers involved, the public is susceptible to political and commercial manipulation of their anxieties and hopes, which undermines the goals of informed consent and shared decision making. What can be done? We discuss the importance of teaching statistical thinking and transparent representations in primary and secondary education as well as in medical school. Yet this requires familiarizing children early on with the concept of probability and teaching statistical literacy as the art of solving real-world problems rather than applying formulas to toy problems about coins and dice. A major precondition for statistical literacy is transparent risk communication. We recommend using frequency statements instead of single-event probabilities, absolute risks instead of relative risks, mortality rates instead of survival rates, and natural frequencies instead of conditional probabilities. Psychological research on transparent visual and numerical forms of risk communication, as well as training of physicians in their use, is called for. Statistical literacy is a necessary precondition for an educated citizenship in a technological democracy. Understanding risks and asking critical questions can also shape the emotional climate in a society so that hopes and anxieties are no longer as easily manipulated from outside and citizens can develop a better-informed and more relaxed attitude toward their health.

Gigerenzer G., Hell W., & Blank H . ( 1988).

Presentation and content: The use of base rates as a continuous variable

Journal of Experimental Psychology: Human Perception and Performance, 14, 513-525.

URL     [本文引用: 1]

The article focuses on the use of base rates as a continuous variable. From its origins circa 1660 until the mid-nineteenth century, probability theory was closely identified with rational thinking. In mathematician P.S. Laplace's famous phrase, probability theory was believed to be "only common sense reduced to calculus." For the classical probabilists, their calculus codified the intuitions of an elite of reasonable men in the face of uncertainty. And if these reasonable intuitions deviated from the laws of probability theory, it was the latter that were cast into doubt. Such discrepancies actually influenced the way in which probability theory developed mathematically.

Gigerenzer G., Hertwig R.,& Pachur, T. , ( 2011) . Heuristics: The foundations of adaptive behavior New York: Oxford University Press The foundations of adaptive behavior. New York: Oxford University Press.

[本文引用: 1]

Gigerenzer, G., &Hoffrage, U. ( 1995).

How to improve Bayesian reasoning without instruction: Frequency formats

Psychological Review, 102, 684-704.

URL     [本文引用: 2]

It is shown that Bayesian algorithms are computationally simpler in frequency formats than in the probability formats used in previous research. Analysis of several thousand solutions to Bayesian problems showed that when information was presented in frequency formats, statistically naive participants derived up to 50% of inferences by Bayesian algorithms. (SLD)

Gigerenzer G., Mata J., & Frank R . ( 2009).

Public knowledge of benefits of breast and prostate cancer screening in Europe

Journal of the National Cancer Institute, 101, 1216-1220.

URL     PMID:19671770      [本文引用: 1]

Making informed decisions about breast and prostate cancer screening requires knowledge of its benefits. However, country-specific information on public knowledge of the benefits of screening is lacking. Face-to-face computer-assisted personal interviews were conducted with 10 228 persons selected by a representative quota method in nine European countries (Austria, France, Germany, Italy, the ...

Gigerenzer G. , & Muir Gray, J. A.( 2011) . Better doctors, better patients, better decisions: Envisioning health care 2020. Cambridge, MA: MIT Press.

[本文引用: 1]

Gigerenzer G. , & Selten, R.( 2001) . Bounded rationality: The adaptive toolbox Cambridge, MA: MIT Press The adaptive toolbox. Cambridge, MA: MIT Press.

[本文引用: 2]

Gigerenzer G., Todd P. M. , & the ABC Research Group.( 1999) . Simple heuristics that make us smart. New York: Oxford University Press.

[本文引用: 1]

Gøtzsche, P. C., & Jørgensen, K. J . ( 2013).

Screening for breast cancer with mammography

Cochrane Database of Systematic Reviews, 6, CD001877.

[本文引用: 1]

Griffiths T. L., Kemp C. , & Tenenbaum, J. B.( 2008) . Bayesian models of cognition. In R. Sun (Ed.), The Cambridge handbook of computational psychology (pp. 59-100). New York: Cambridge University Press.

[本文引用: 1]

Hertwig R., Pachur T., & Kurzenhäuser S . ( 2005).

Judgments of risk frequencies: Tests of possible cognitive mechanisms

Journal of Experimental Psychology: Learning, Memory, & Cognition, 31, 621-642.

URL     PMID:16060769      [本文引用: 2]

How do people judge which of 2 risks claims more lives per year? The authors specified 4 candidate mechanisms and tested them against people's judgments in 3 risk environments. Two mechanisms, availability by recall and regressed frequency, conformed best to people's choices. The same mechanisms also accounted well for the mapping accuracy of estimates of absolute risk frequencies. Their nearly indistinguishable level of performance is remarkable given their different assumptions about the underlying cognitive processes and the fact that they give rise to different expectations regarding the accuracy of people's inferences. The authors discuss this seeming paradox, the lack of impact of financial incentives on judgmental accuracy, and the dominant interpretation of inaccurate inferences in terms of biased information processing.

Hoffrage U., Lindsey S., Hertwig R., & Gigerenzer G . ( 2000).

Communicating statistical information

Science, 290, 2261-2262.

URL     [本文引用: 1]

Juslin P., Winman A., & Olsson H . ( 2000).

Naive empiricism and dogmatism in confidence research: A critical examination of the hard-easy effect

Psychological Review, 107, 384-396.

URL     PMID:10789203      [本文引用: 1]

Two robust phenomena in research on confidence in one's general knowledge are the overconfidence phenomenon and the hard-easy effect. In this article, the authors propose that the hard-easy effect has been interpreted with insufficient attention to the scale-end effects, the linear dependency, and the regression effects in data and that the continued adherence to the idea of a "cognitive overconfidence bias" is mediated by selective attention to particular data sets. A quantitative review of studies with 2-alternative general knowledge items demonstrates that, contrary to widespread belief, there is (a) very little support for a cognitive-processing bias in these data; (b) a difference between representative and selected item samples that is not reducible to the difference in difficulty; and (c) near elimination of the hard-easy effect when there is control for scale-end effects and linear dependency.

Kahneman,D. ( 2011).

Thinking fast and slow

London: Allen Lane.

[本文引用: 2]

Kahneman, D., &Tversky, A. ( 1972).

Subjective probability: A judgment of representativeness

Cognitive Psychology, 3, 430-454.

URL     [本文引用: 1]

This paper explores a heuristic — representativeness — according to which the subjective probability of an event, or a sample, is determined by the degree to which it: (i) is similar in essential characteristics to its parent population; and (ii) reflects the salient features of the process by which it is generated. This heuristic is explicated in a series of empirical examples demonstrating predictable and systematic errors in the evaluation of uncertain events. In particular, since sample size does not represent any property of the population, it is expected to have little or no effect on judgment of likelihood. This prediction is confirmed in studies showing that subjective sampling distributions and posterior probability judgments are determined by the most salient characteristic of the sample (e.g., proportion, mean) without regard to the size of the sample. The present heuristic approach is contrasted with the normative (Bayesian) approach to the analysis of the judgment of uncertainty.

Kahneman, D., &Tversky, A. ( 1973).

On the psychology of prediction

Psychological Review, 80, 237-251.

URL     [本文引用: 2]

Kleiter, G. D . ( 1994).

Natural sampling: Rationality without base rates

In G. H. Fischer & D. Laming (Eds.), Contributions to mathematical psychology, psychometrics, and methodology(pp. 375-388). New York: Springer.

URL     [本文引用: 1]

Abstract The Bayesian classification of single cases into classes is investigated. The neglect of class base rates is usually considered to be a fundamental violation of the principles of rationality and, in human judgment, is called ‘the base rate fallacy’. This paper analyzes an important special sampling condition in which the base rates actually turn out to be irrelevant in estimating classification probabilities. It is shown that the base rates do not affect the precision of the estimates of classification probability. This precision is modeled by a second-order probability distribution. Implications for the design of artificial and for the modeling of natural knowledge systems are discussed.

Knight, F. H . ( 1921).

Risk, uncertainty and profit (Vol. XXXI)

Boston: Houghton Mifflin.

[本文引用: 1]

Kösters, J. P., & Gøtzsche, P. C . ( 2003).

Regular self- examination or clinical examination for early detection of breast cancer

Cochrane Database of Systematic Reviews, 2, CD003373.

URL     PMID:15830497      [本文引用: 1]

Abstract Background Breast self-examination and clinical breast examination have been promoted for many years as general screening methods to diagnose breast cancer at an early stage in order to decrease morbidity and mortality. The possible benefits and harms remain unclear. Objectives To determine whether screening for breast cancer by regular self-examination or clinical breast examination reduces breast cancer mortality and morbidity. Search methods For this update, the Cochrane Breast Cancer Group Specialised Register, The Cochrane Library and PubMed were searched (October 2007). Selection criteria Randomised clinical trials, including cluster randomised trials. Data collection and analysis Decisions on which trials to include were taken independently by the authors based on the methods of a trial. Disagreements were resolved by discussion. Intention-to-treat analyses were conducted using a fixed-effect model with 95% confidence intervals. Main results Two large population-based studies (388,535 women) from Russia and Shanghai that compared breast self-examination with no intervention were included. There was no statistically significant difference in breast cancer mortality between the groups (relative risk 1.05, 95% confidence interval (CI) 0.90 to 1.24; 587 deaths in total). In Russia, more cancers were found in the breast self-examination group than in the control group (relative risk 1.24, 95% CI 1.09 to 1.41) while this was not the case in Shanghai (relative risk 0.97, 95% CI 0.88 to 1.06). Almost twice as many biopsies (3406) with benign results were performed in the screening groups compared to the control groups (1856) (relative risk 1.88, 95% CI 1.77 to 1.99). One large population-based trial of clinical breast examination combined with breast self-examination was also included. The intervention was discontinued because of poor compliance with follow up and no conclusions could be drawn. Authors' conclusions Data from two large trials do not suggest a beneficial effect of screening by breast self-examination but do suggest increased harm in terms of increased numbers of benign lesions identified and an increased number of biopsies performed. At present, screening by breast self-examination or physical examination cannot be recommended.

Kühberger,A. ( 1995).

The framing of decisions: A new look at old problems

Organizational Behavior and Human Decision Processes, 62, 230-240.

URL     [本文引用: 1]

The term framing is used to refer to the various ways decision situations are presented that lead decision makers to construct markedly different representations of such situations, In two experiments using Asian disease-like decision problems, we tested for the persistence of framing effects dependent on the amount and quality of information presented. In standard wordings these problems are not fully described, yet it is hardly ever reported that information is missing. Additionally, we investigated the perceived ambiguity of the values presented in the problem descriptions, Variation of missing items of information produced markedly different framing effects: With fully described problems, no framing effects emerged, With standard wording, the framing effect was most pronounced in the negative framing condition, While risk-aversion with positive framing was not very strong, with some of the problems worded in a novel fashion we found a reversal of the standard framing effect, The problems were interpreted by subjects as ambiguous to a considerable degree, but ambiguity was not related to subjects' choices, The results are discussed in a framework explicitly distinguishing domain effects from framing effects, Unlike earlier attempts with prospect theory, or, more recently, with fuzzy-trace theory, we propose that probabilistic mental models theory explains framing effects. (C) 1995 Academic Press, Inc.

Kühberger, A., &Gradl, P. ( 2013).

Choice, rating, and ranking: Framing effects with different response modes

Journal of Behavioral Decision Making, 26, 109-117.

URL     [本文引用: 1]

In a typical risky choice framing task, people have to choose among two options, which are either positively or negatively framed. Choices in the two framing conditions are then compared. However, different preferences between the conditions can be due to changes in the evaluation of the single constituent options or due to specific processes triggered by the choice task. In order to clarify the source of the framing effect, we investigate the effect with different response modes: choice, rating, and ranking. The rating and ranking findings indicate that what is commonly called a risky choice framing effect is actually a framing effect that changes the evaluation of only the riskless option, although there is little or no effect on the risky option. According to these findings, risky choice framing might be construed as a process of attribute framing, which is independent of risk preference in choice contexts. Copyright 2011 John Wiley & Sons, Ltd.

Kühberger, A., &Tanner, C. ( 2010).

Risky choice framing: Task versions and a comparison of prospect theory and fuzzy-trace theory

Journal of Behavioral Decision Making, 23, 314-329.

URL     [本文引用: 1]

Abstract Framing effects are said to indicate irrationality in decision making because they illustrate that linguistically different descriptions of equivalent options lead to inconsistent choices. A review of the literature on the effects of adding, or subtracting, implicated complements of the sure option shows that this leads to a classic framing effect, a reversal of the classic effect, or no framing effect. Thus, the assumption of equivalence of formulations is not justified. In addition we provide a test of two major, but opposing theories on framing, prospect theory and fuzzy-trace theory. Based on an online study we investigated the effects of subtracting complements of the risky option. The results are more consistent with fuzzy-trace theory than with prospect theory. The consequences of these findings for the application of formal models like prospect theory, and for rationality, are discussed. Copyright 2009 John Wiley & Sons, Ltd.

Lindsey S., Hertwig R., & Gigerenzer G . ( 2003).

Communicating statistical DNA evidence

Jurimetrics, 43, 147-163.

[本文引用: 1]

Luan S., Schooler L. J., & Gigerenzer G . ( 2011).

A signal- detection analysis of fast-and-frugal trees

Psychological Review, 118, 316-338.

URL     PMID:21381858      [本文引用: 1]

Abstract Models of decision making are distinguished by those that aim for an optimal solution in a world that is precisely specified by a set of assumptions (a so-called "small world") and those that aim for a simple but satisfactory solution in an uncertain world where the assumptions of optimization models may not be met (a so-called "large world"). Few connections have been drawn between these 2 families of models. In this study, the authors show how psychological concepts originating in the classic signal-detection theory (SDT), a small-world approach to decision making, can be used to understand the workings of a class of simple models known as fast-and-frugal trees (FFTs). Results indicate that (a) the setting of the subjective decision criterion in SDT corresponds directly to the choice of exit structure in an FFT; (b) the sensitivity of an FFT (measured in d') is reflected by the order of cues searched and the properties of cues in an FFT, including the mean and variance of cues' individual d's, the intercue correlation, and the number of cues; and (c) compared with the ideal and the optimal sequential sampling models in SDT and a majority model with an information search component, FFTs are extremely frugal (i.e., do not search for much cue information), highly robust, and well adapted to the payoff structure of a task. These findings demonstrate the potential of theory integration in understanding the common underlying psychological structures of apparently disparate theories of cognition. 2011 APA, all rights reserved

Luan S., Schooler L. J., & Gigerenzer G . ( 2014).

From perception to preference and on to inference: An approach-avoidance analysis of thresholds

Psychological Review, 121, 501-525.

URL     [本文引用: 1]

In a lexicographic semiorders model for preference, cues are searched in a subjective order, and an alternative is preferred if its value on a cue exceeds those of other alternatives by a threshold Δ, akin to a just noticeable difference in perception. We generalized this model from preference to inference and refer to it as Δ-inference. Unlike with preference, where accuracy is difficult to define, the problem a mind faces when making an inference is to select a Δ that can lead to accurate judgments. To find a solution to this problem, we applied Clyde Coombs's theory of single-peaked preference functions. We show that the accuracy of Δ-inference can be understood as an approach-avoidance conflict between the decreasing usefulness of the first cue and the increasing usefulness of subsequent cues as Δ grows larger, resulting in a single-peaked function between accuracy and Δ. The peak of this function varies with the properties of the task environment: The more redundant the cues and the larger the differences in their information quality, the smaller the Δ. An analysis of 39 real-world task environments led to the surprising result that the best inferences are made when Δ is 0, which implies relying almost exclusively on the best cue and ignoring the rest. This finding provides a new perspective on the take-the-best heuristic. Overall, our study demonstrates the potential of integrating and extending established concepts, models, and theories from perception and preference to improve our understanding of how the mind makes inferences.

Mandel D. R . ( 2001).

Gain-loss framing and choice: Separating outcome formulations from descriptor formulations

Organizational Behavior and Human Decision Processes, 85, 56-76.

URL     PMID:11341817      [本文引用: 1]

This article reexamines the assumptions underlying the disease problem used by Tversky and Kahneman (1981) to illustrate gain-loss formulation effects. It is argued that their reported effect may have been due to asymmetries in the ambiguity of the sure and risky prospects and to the entanglement of two distinct types of formulation manipulations: one having to do with the expected outcomes that are made explicit (positive vs negative) and the other having to do with the descriptors used to convey the relevant expected outcomes (lives saved/not saved vs lives lost/not lost). Two experiments using a formally equivalent problem in which these confounds were eliminated revealed no significant predictive effect of either descriptor or outcomes frames on choice, although a marginally significant framing effect was obtained in Experiment 1 when the signs of the two framing manipulations were congruent. Implications for prospect theory are discussed.

McKenzie, C. R. M., & Nelson J.D, . ( 2003).

What a speaker's choice of frame reveals: Reference points, frame selection, and framing effects

Psychonomic Bulletin and Review, 10, 596-602.

URL     PMID:14620352      [本文引用: 1]

Framing effects are well established: Listeners’ preferences depend on how outcomes are described to them, or framed. Less well understood is what determines how speakers choose frames. Two experiments revealed that reference points systematically influenced speakers’ choices between logically equivalent frames. For example, speakers tended to describe a 4-ounce cup filled to the 2-ounce line as half full if it was previously empty but described it as half empty if it was previously full. Similar results were found when speakers could describe the outcome of a medical treatment in terms of either mortality or survival (e.g., 25% die vs. 75% survive). Two additional experiments showed that listeners made accurate inferences about speakers’ reference points on the basis of the selected frame (e.g., if a speaker described a cup as half empty, listeners inferred that the cup used to be full). Taken together, the data suggest that frames reliably convey implicit information in addition to their explicit content, which helps explain why framing effects are so robust.

Meyerowtiz, B. E.,& Chaiken, S. , ( 1987).

The effect of message framing on breast self-examination attitudes, intentions, and behavior

Journal of Personality and Social Psychology, 52, 509-510.

URL     PMID:3572721      [本文引用: 1]

In this study we tested the framing hypothesis that a pamphlet stressing the negative consequences of not performing breast self-examination (BSE) would be more persuasive than a pamphlet emphasizing BSE's positive consequences. College-aged female subjects were exposed to a loss-frame pamphlet, a gain-frame pamphlet, or a no-arguments pamphlet, or they received no pamphlet describing the importance of and the techniques for performing BSE. Attitudes toward BSE and intentions to perform BSE were assessed immediately after this intervention and again 4 months later. The follow-up also assessed subjects' postexperimental BSE behavior. Consistent with predictions, subjects who read a pamphlet with arguments framed in loss language manifested more positive BSE attitudes, intentions, and behaviors than did subjects in the other three conditions. The greater impact of the loss pamphlet could not be attributed to greater fear arousal, better memory for pamphlet content, greater perceived susceptibility to breast cancer, or stronger beliefs in BSE's efficacy on the part of the loss subjects. Only measures of perceived self-efficacy in performing BSE were differentially affected by the framing manipulation, with loss subjects reporting the greatest levels of self-confidence. The results are discussed in terms of prospect theory's framing postulate and a simpler negativity-bias conceptualization, and underlying mechanisms such as differential salience and vividness are considered. Clinical implications of the findings are also explored.

Moxey A., O’Connell D., McGettigan P., & Henry D . ( 2003).

Describing treatment effects to patients: How they are expressed makes a difference

Journal of General Internal Medicine, 18, 948-959.

URL     PMID:14687282      [本文引用: 1]

OBJECTIVE: To examine the impact of different presentations of equivalent information (framing) on treatment decisions faced by patients.

Multmeier,J. ( 2012).

Representations facilitate Bayesian reasoning: Computational facilitation and ecological design revisited

Unpublished manuscript.

[本文引用: 1]

Nisbett, R. E . ( 2009).

Intelligence and how to get it: Why schools and cultures count

New York: Norton.

[本文引用: 1]

Norman,D. ( 1990).

The design of everyday things

New York: Doubleday.

[本文引用: 1]

Parikh,P. ( 2009).

Value investing and behavioral finance: Insights into Indian stock market realities

New Delhi: Tata McGraw-Hill Education.

[本文引用: 1]

Rebonato,R. ( 2012).

Taking liberties: A critical examination of libertarian paternalism

Basingstoke, United Kingdom: Palgrave Macmillan.

[本文引用: 2]

Savage, L. J . ( 1954).

The foundations of statistics

New York: Wiley.

[本文引用: 1]

Schooler, L. J., & Anderson, J. R . ( 1997).

The role of process in the rational analysis of memory

Cognitive Psychology, 32, 219-250.

URL     [本文引用: 1]

The rational analysis of memory (Anderson, 1990) proposes that memory's sensitivity to statistical structure in the environment enables it to optimally estimate the odds that a memory trace will be needed. We have analyzed sources of informational demand in the environment: speech to children and word usage in the front page headlines of the New York Times. In a previous paper (Anderson & Schooler, 1991) we have shown that factors that govern memory performance, including recency, also predict the odds that an item (e.g., a word) will be encountered. In the present paper we develop the theory to make precise predictions about how the odds of encountering an item now varies as a joint function of (1) the statistical associations between the item and elements of the current context and (2) how long it has been since the item was last encountered. The prediction was confirmed environmentally by analyses of the New York Times and speech to children. The corresponding behavioral prediction was tested, using a cued recall task in which the cues were either strongly associated or unassociated to the targets. In contrast to the environmental results, recall performance is more sensitive to the length of the retention interval in the presence of unassociated cues than in the presence of associated cues. Further modeling shows that incorporating estimates of the influence of non-retrieval processes (e.g., reading a word, deciding to respond, etc.) on overall performance reduces the discrepancy between the theoretical predictions and the observed data.

Sedlmeier, P., &Gigerenzer, G. ( 2001).

Teaching Bayesian reasoning in less than two hours

Journal of Experimental Psychology: General, 130, 380-400.

URL     [本文引用: 1]

Sher, S., & McKenzie, C. R. M . ( 2006).

Information leakage from logically equivalent frames

Cognition, 101, 467-494.

URL     PMID:16364278      [本文引用: 1]

Framing effects are said to occur when equivalent frames lead to different choices. However, the equivalence in question has been incompletely conceptualized. In a new normative analysis of framing effects, we complete the conceptualization by introducing the notion of information equivalence. Information equivalence obtains when no choice-relevant inferences can be drawn from the speaker’s choice of frame. We show that, to support the normative implications traditionally attributed to framing effects, frames must be equivalent in this sense. We also present new evidence for McKenzie and Nelson’s (2003) reference point hypothesis, which posits a tendency to cast descriptions in terms of what has increased relative to the reference point. This leakage of information about relative state violates information equivalence, and gives rise to a normative account of the most robust finding in the attribute framing literature—the valence-consistency of preference shifts. We argue that, more generally, valenced descriptions leak information about perceived valence. Such “implicit recommendations” may generalize the reference point explanation of the valence-consistent shift. Normative and psychological implications of the information leakage framework are discussed.

Salovey, P., &Williams-Piehota, P. ( 2004).

Field experiments in social psychology: Message framing and the promotion of health protective behaviors

American Behavioral Scientist, 47, 488-505.

URL     [本文引用: 1]

In this article, the authors present the case for field experimentationin social psychology primarily by describing a program of research concerned with psychological aspects of health communication and persuasion. In particular, the authors are most interested in when and for whom are messages emphasizing the benefits of a health behavior (these are called gain-framed messages) more persuasive and motivating than messages emphasizing the costs of not engagingin a behavior(these are called loss-framed messages), andvice-versa. This line of research is as theoretically driven as most laboratory investigations in social psychology, and it involves experimental approaches with random assignment, control groups, and the like. However, most of this work recruits participants in ecologically interesting contexts such as community clinics and housing developments. These especially vulnerable individuals are followed for sufficient periods of time to allow for the assessment of the influence of these health messages on relevant health behaviors such as obtaining a mammogram or acquiring condoms.

Slovic P., Fischhoff B.& Lichtenstein, S. , ( 1982).

Facts versus fears: Understanding perceived risk

In D. Kahneman, P. Slovic, & A. Tversky (Eds.), Judgment under uncertainty: Heuristics and biases (pp. 463-492). Cambridge, United Kingdom: Cambridge University Press.

URL     [本文引用: 1]

Subjective judgments, whether by experts or lay people, are a major component in any risk assessment. If such judgments are faulty, efforts at public and environmental protection are likely to be misdirected. The present paper begins with an analysis of biases exhibited by lay people and experts when they make judgments about risk. Next, the similarities and differences between lay and expert evaluations are examined in the context of a specific set of activities and technologies. Finally, some special issues are discussed, including the difficulty of reconciling divergent opinions about risk, the possible irrelevance of voluntariness as a determinant of acceptable risk, the importance of catastrophic potential in determing perceptions and triggering social conflict, and the need to facilitate public participation in the management of hazards.

Spiegelhalter D., Pearson M., & Short I . ( 2011).

Visualizing uncertainty about the future

Science, 333, 1393-1400.

URL     PMID:21903802      [本文引用: 2]

We are all faced with uncertainty about the future, but we can get the measure of some uncertainties in terms of probabilities. Probabilities are notoriously difficult to communicate effectively to lay audiences, and in this review we examine current practice for communicating uncertainties visually, using examples drawn from sport, weather, climate, health, economics, and politics. Despite the burgeoning interest in infographics, there is limited experimental evidence on how different types of visualizations are processed and understood, although the effectiveness of some graphics clearly depends on the relative numeracy of an audience. Fortunately, it is increasingly easy to present data in the form of interactive visualizations and in multiple types of representation that can be adjusted to user needs and capabilities. Nonetheless, communicating deeper uncertainties resulting from incomplete or disputed knowledge—or from essential indeterminacy about the future—remains a challenge.

Studdert D. M., Mello M. M., Sage W. M., DesRoches C. M., Peugh J., Zapert K., & Brennan M. D . ( 2005).

Defensive medicine among high-risk specialist physicians in a volatile malpractice environment

JAMA, 293, 2609-2617.

URL     PMID:15928282     

How often physicians alter their clinical behavior because of the threat of malpractice liability, termed defensive medicine, and the consequences of those changes, are central questions in the ongoing medical malpractice reform debate.To study the prevalence and characteristics of defensive medicine among physicians practicing in high-liability specialties during a period of substantial instability in the malpractice environment.Mail survey of physicians in 6 specialties at high risk of litigation (emergency medicine, general surgery, orthopedic surgery, neurosurgery, obstetrics/gynecology, and radiology) in Pennsylvania in May 2003.Number of physicians in each specialty reporting defensive medicine or changes in scope of practice and characteristics of defensive medicine (assurance and avoidance behavior).A total of 824 physicians (65%) completed the survey. Nearly all (93%) reported practicing defensive medicine. "Assurance behavior" such as ordering tests, performing diagnostic procedures, and referring patients for consultation, was very common (92%). Among practitioners of defensive medicine who detailed their most recent defensive act, 43% reported using imaging technology in clinically unnecessary circumstances. Avoidance of procedures and patients that were perceived to elevate the probability of litigation was also widespread. Forty-two percent of respondents reported that they had taken steps to restrict their practice in the previous 3 years, including eliminating procedures prone to complications, such as trauma surgery, and avoiding patients who had complex medical problems or were perceived as litigious. Defensive practice correlated strongly with respondents' lack of confidence in their liability insurance and perceived burden of insurance premiums.Defensive medicine is highly prevalent among physicians in Pennsylvania who pay the most for liability insurance, with potentially serious implications for cost, access, and both technical and interpersonal quality of care.

Sunstein C. R. ( 2005). Laws of fear: Beyond the precautionary principle. Cambridge, United Kingdom: Cambridge University Press.

[本文引用: 1]

Sunstein, C. R . ( 2013).

The Storrs lectures: Behavioral economics and paternalism

The Yale Law Journal, 122, 1826-1899.

URL    

A growing body of evidence demonstrates that in some contexts and for identifiable reasons, people make choices that are not in their interest, even when the stakes are high. Policymakers in a number of Nations, including the United States and the United Kingdom, have used this evidence to inform regulatory initiatives and choice architecture. Both the resulting actions and the relevant findings have raised the possibility that an understanding of human errors opens greater space for paternalism (and thus raises doubts about John Stuart Mill's famous "harm principle"). Such errors can be thought of as behavioral market failures, and they are an important supplement to the standard account of market failures. Actions taken to correct behavioral market failures can sometimes be justified, even if the resulting actions are paternalistic. While hard forms of paternalism cannot be ruled out of bounds, a general principle of behaviorally informed regulation 09“ its first and only law 09“ is that the appropriate responses to behavioral market failures usually consist of nudges, generally in the form of disclosure, warnings, and default rules. Some people invoke autonomy as an objection to paternalism, but the strongest objections are welfarist in character. Official action may fail to respect heterogeneity, may diminish learning and self-help, may be subject to pressures from self-interested private groups (the problem of 'behavioral public choice"), and may reflect the same errors that ordinary people make. Where paternalism is optional, the objections, though plausible, are unhelpfully abstract; they depend on empirical assumptions that may not hold in identifiable contexts. There are many Opportunities for improving human welfare through improved choice architecture.

Thaler, R. H . ( 1991).

Quasi rational economics

New York: Russell Sage Foundation.

[本文引用: 1]

Thaler, R. H., & Sunstein, C. R . ( 2003).

Libertarian paternalism

American Economic Review, 93, 175-179.

URL     [本文引用: 2]

Thaler R. H.& Sunstein, C. R. , (2008). Nudge: Improving decisions about health, wealth, and happiness New Haven, CT: Yale University Press Improving decisions about health, wealth, and happiness. New Haven, CT: Yale University Press.

[本文引用: 6]

Till, C . ( 2014).

Risk literacy: First steps in primary school

In K. Makar, B. de Sousa, & R. Gould (Eds.), Sustainability in statistics education. Proceedings of the Ninth International Conference on Teaching Statistics (ICOTS9).Voorburg, The Netherlands: International Statistical Institute.

[本文引用: 1]

Trout, J. D . ( 2005).

Paternalism and cognitive bias

Law and Philosophy, 24, 393-434.

URL     [本文引用: 1]

Tversky, A., &Kahneman, D. ( 1980).

Causal schemata in judgments under uncertainty. In M. Fishbein (Ed.), Progress in social psychology

(Vol. 1, pp. 49-72). Hillsdale, NJ: Erlbaum.

[本文引用: 1]

Tversky, A., &Kahneman, D. ( 1981).

The framing of decisions and the psychology of choice

Science, 211, 453-458.

URL     [本文引用: 1]

Tversky, A., &Kahneman, D. ( 1986).

Rational choice and the framing of decisions

The Journal of Business, 59, S251-S278.

URL     [本文引用: 1]

Alternative descriptions of a decision problem often give rise to different preferences, contrary to the principle of invariance that underlies the rational theory of choice. Violations of this theory are traced to the rules that govern the framing of decision and to the psychophysical principles of evaluation embodied in prospect theory. Invariance and dominance are obeyed when their application is transparent and often violated in other situations. Because these rules are normatively essential but descriptively invalid, no theory of choice can be both normatively adequate and descriptively accurate.

Wegwarth O., Schwartz L. M., Woloshin S., Gaissmaier W., & Gigerenzer G . ( 2012).

Do physicians understand cancer screening statistics? A national survey of primary care physicians in the United States

Annals of Internal Medicine, 156, 340-349.

URL     PMID:22393129      [本文引用: 1]

Unlike reduced mortality rates, improved survival rates and increased early detection do not prove that cancer screening tests save lives. Nevertheless, these 2 statistics are often used to promote screening.To learn whether primary care physicians understand which statistics provide evidence about whether screening saves lives.Parallel-group, randomized trial (randomization controlled for order effect only), conducted by Internet survey. (ClinicalTrials.gov registration number: NCT00981019)National sample of U.S. primary care physicians from a research panel maintained by Harris Interactive (79% cooperation rate).297 physicians who practiced both inpatient and outpatient medicine were surveyed in 2010, and 115 physicians who practiced exclusively outpatient medicine were surveyed in 2011.Physicians received scenarios about the effect of 2 hypothetical screening tests: The effect was described as improved 5-year survival and increased early detection in one scenario and as decreased cancer mortality and increased incidence in the other.Physicians' recommendation of screening and perception of its benefit in the scenarios and general knowledge of screening statistics.Primary care physicians were more enthusiastic about the screening test supported by irrelevant evidence (5-year survival increased from 68% to 99%) than about the test supported by relevant evidence (cancer mortality reduced from 2 to 1.6 in 1000 persons). When presented with irrelevant evidence, 69% of physicians recommended the test, compared with 23% when presented with relevant evidence (P < 0.001). When asked general knowledge questions about screening statistics, many physicians did not distinguish between irrelevant and relevant screening evidence; 76% versus 81%, respectively, stated that each of these statistics proves that screening saves lives (P = 0.39). About one half (47%) of the physicians incorrectly said that finding more cases of cancer in screened as opposed to unscreened populations "proves that screening saves lives."Physicians' recommendations for screening were based on hypothetical scenarios, not actual practice.Most primary care physicians mistakenly interpreted improved survival and increased detection with screening as evidence that screening saves lives. Few correctly recognized that only reduced mortality in a randomized trial constitutes evidence of the benefit of screening.Harding Center for Risk Literacy, Max Planck Institute for Human Development.

Welch H. G. ( 2004). Should I be tested for cancer? Berkeley, CA: University of California Press.

[本文引用: 1]

Woloshin, S., & Schwartz L. M, . ( 2012).

How a charity oversells mammography

BMJ, 345, e5132.

URL     PMID:22859787      [本文引用: 1]

In their occasional series highlighting the exaggerations, distortions, and selective reporting that make some news stories, advertising, and medical journal articles “not so,” Lisa M Schwartz and Steven Woloshin explain how a charity used misleading statistics to persuade women to undergo mammography

Woloshin S., Schwartz L. M.& Welch, H. G. , ( 2008) . Know your chances: Understanding health statistics Berkeley, CA: University of California Press Understanding health statistics. Berkeley, CA: University of California Press.

[本文引用: 1]

Yu,Y., & Li,S , ( 2006).

"Overconfidence" and its cross- cultural variation

Advances in Psychological Science, 14, 468-474.

URL     [本文引用: 1]

Overconfidence refers to that subjects average probability judgments exceed the proportions of items they answer correctly over a wide range of conditions. A series of cross-cultural researches indicate that respondents in Asian cultures (e.g., Chinese) are more risk-seeking and more overconfident than respondents in other cultures (e.g., in United States) and that the reciprocal predictions are in total opposition. This paper presents recent researches on overconfidence from traditional and alternative frameworks. The implications for cross-cultural variations in overconfidence were discussed

[ 于窈, 李纾 . ( 2006).

“过分自信”的研究及其跨文化差异

心理科学进展, 14( 3), 468-474.]

URL     [本文引用: 1]

Overconfidence refers to that subjects average probability judgments exceed the proportions of items they answer correctly over a wide range of conditions. A series of cross-cultural researches indicate that respondents in Asian cultures (e.g., Chinese) are more risk-seeking and more overconfident than respondents in other cultures (e.g., in United States) and that the reciprocal predictions are in total opposition. This paper presents recent researches on overconfidence from traditional and alternative frameworks. The implications for cross-cultural variations in overconfidence were discussed

Zhu, L., &Gigerenzer, G. ( 2006).

Children can solve Bayesian problems: The role of representation in mental computation

Cognition, 98, 287-308.

URL     PMID:16399266      [本文引用: 1]

Can children reason the Bayesian way? We argue that the answer to this question depends on how numbers are represented, because a representation can do part of the computation. We test, for the first time, whether Bayesian reasoning can be elicited in children by means of natural frequencies. We show that when information was presented to fourth, fifth, and sixth graders in terms of probabilities, their ability to estimate the Bayesian posterior probability was zero. Yet when the same information was presented in natural frequencies, Bayesian reasoning showed a steady increase from fourth to sixth grade, reaching an average level of 19, 39, and 53%, respectively, in two studies. Sixth graders' performance with natural frequencies matched the performance of adults with probabilities. But this general increase was accompanied by striking individual differences. More than half of the sixth graders solved most or all problems, whereas one third could not solve a single one. An analysis of the children's responses provides evidence for the use of three non-Bayesian strategies. These follow an overlapping wave model of development and continue to be observed in the minds of adults. More so than adults' probabilistic reasoning, children's reasoning depends on a proper representation of information.

版权所有 © 《心理学报》编辑部
本系统由北京玛格泰克科技发展有限公司设计开发  技术支持:support@magtech.com.cn

/