什么是行为经济学？
行为经济学建立在对人类行为的实证观察的基础上，这些观察表明，人们并不总是做出新古典经济学家认为的“理性”或“最佳”决策，即使他们拥有可用的信息和工具。
例如，为什么人们经常避免或推迟投资 401ks 或锻炼，即使他们知道做这些事情会给他们带来好处？ 为什么赌徒在输赢后往往会冒更大的风险，即使赔率保持不变，无论“连胜”如何？
行为经济学解释
https://news.uchicago.edu/explainer/what-is-behavioral-economics#:~:text=Behavioral%20economics%20combines
作者：马克斯·维廷斯基
行为科学和经济学查尔斯·R·沃尔格林杰出服务教授理查德·塞勒 (Richard Thaler) 概述了工作中“推动”的一些例子。
视频由芝加哥大学提供
行为经济学结合了经济学和心理学的元素，以了解人们在现实世界中的行为方式和原因。 它与新古典经济学不同，新古典经济学假设大多数人都有明确的偏好，并根据这些偏好做出明智的、利己的决策。
行为经济学受到芝加哥大学学者、诺贝尔奖获得者理查德·泰勒的领域定义工作的影响，研究人们“应该”做什么和他们实际做什么之间的差异以及这些行为的后果。
什么是行为经济学？
行为经济学建立在对人类行为的实证观察的基础上，这些观察表明，人们并不总是做出新古典经济学家认为的“理性”或“最佳”决策，即使他们拥有可用的信息和工具。
例如，为什么人们经常避免或推迟投资 401ks 或锻炼，即使他们知道做这些事情会给他们带来好处？ 为什么赌徒在输赢后往往会冒更大的风险，即使赔率保持不变，无论“连胜”如何？
通过提出这样的问题并通过实验确定答案，行为经济学领域将人视为容易受到情感和冲动影响并受到环境和情况影响的人。
这种特征与传统经济模型形成鲜明对比，传统经济模型将人们视为纯粹理性的行为者（具有完美的自我控制能力，永远不会忘记自己的长期目标），或者视为偶尔犯下随机错误的人，这些错误从长远来看会抵消 。
行为经济学研究中出现的一些原则可以帮助经济学家更好地理解人类经济行为。 根据这些原则，政府和企业制定了政策框架来鼓励人们做出特定的选择。
行为经济学研究的起源是什么？特沃斯基和卡尼曼是谁？
行为经济学自 20 世纪 80 年代以来不断发展，但它有着悠久的历史：根据塞勒的说法，该领域的一些重要思想可以追溯到 18 世纪苏格兰经济学家亚当·斯密。
斯密经常因“看不见的手”的概念而被人们铭记，如果每个人都做出自己利己的决定，那么“看不见的手”就会引导整体经济走向繁荣——这是古典和新古典经济学的一个关键概念。 但他也认识到，人们往往对自己的能力过于自信，更害怕失败而不是渴望胜利，更倾向于追求短期利益而不是长期利益。 这些思想（过度自信、损失厌恶和自我控制）是当今行为经济学的基本概念。
最近，行为经济学早期源于以色列心理学家阿莫斯·特沃斯基和丹尼尔·卡尼曼关于不确定性和风险的研究。 在 20 世纪 70 年代和 80 年代，特沃斯基和卡尼曼在人们做出判断的方式中发现了一些一致的偏见，发现人们在评估特定结果的可能性时经常依赖容易回忆的信息，而不是实际数据，这一概念被称为“ “可用性启发式。” 例如，如果人们读过有关鲨鱼或熊袭击的报道，他们可能会认为鲨鱼或熊的袭击是一种常见的死亡原因，但这些事件实际上非常罕见。
特沃斯基和卡尼曼还通过“前景理论”证明了框架和损失厌恶会影响人们做出的选择。 例如，如果有机会保证赢取 250 美元，或者赌博有 25% 的机会赢得 1,000 美元，而 75% 的机会一无所获，大多数人都会选择必赢。 但如果有机会保证损失 750 美元，或者有 75% 的机会损失 1,000 美元，还有 25% 的机会什么都不损失，大多数人会冒着损失 1,000 美元的风险，希望自己什么也不会损失的可能性微乎其微。
这个经典的例子表明，如果与获得 1,000 美元的盈利相比，避免 1,000 美元的损失，人们更愿意承担更大的统计风险，这与预期效用理论相矛盾。 前景理论以及特沃斯基和卡尼曼的其他工作继续为当今行为经济学研究的许多领域提供信息。
理查德·泰勒和芝加哥大学的行为经济学家在该领域的发展中发挥了什么作用？
20 世纪 80 年代，理查德·塞勒 (Richard Thaler) 开始以特沃斯基和卡尼曼的工作为基础，并与他们进行了广泛的合作。 他现在是布斯商学院行为科学和经济学查尔斯·R·沃尔格林杰出服务教授，如今被认为是行为经济学领域的创始人。
塞勒在识别指导个人经济决策的因素方面的研究为他赢得了 2017 年瑞典央行纪念阿尔弗雷德·诺贝尔经济科学奖。他的想法部分源于他在研究生院所做的一系列观察，这些观察使他 相信人们的行为以可预测的方式偏离了传统经济模式。
例如，塞勒观察到，他和一位朋友愿意因暴风雪而放弃开车去观看体育赛事，因为他们获得了免费门票。 但如果他们自己买票，他们会更愿意去，尽管票价无论如何都是一样的，而且在暴风雪中开车的危险性也没有改变。 这是“沉没成本谬误”的一个例子，即人们不太愿意放弃自己亲自投资的项目，即使这意味着更多的风险。
塞勒还因普及“助推”概念而闻名，这是一种引导人们做出更好决策的概念手段。 “助推”利用了人类心理学和行为经济学中的许多其他概念，包括心理账户，即人们根据环境以不同方式对待金钱的想法。 例如，人们更愿意开车穿过城镇，购买 20 美元的商品可以节省 10 美元，而不是购买 1,000 美元的商品可以节省 10 美元，尽管所付出的努力和节省的金额是相同的。
塞勒和其他芝加哥大学经济学家——包括莱昂纳多·布尔斯廷（Leonardo Bursztyn）、乔什·迪安（Josh Dean）、尼古拉斯·埃普利（Nicholas Epley）、奥斯坦·古尔斯比（Austan Goolsbee）、亚历克斯·伊马斯（Alex Imas）、约翰·李斯特（John List）、苏珊·梅尔（Susan Mayer）、森德希尔·穆莱纳坦（Sendhil Mullainathan）、德文·波普（Devin Pope）、丽贝卡·迪宗·罗斯（Rebecca Dizon Ross）和希瑟·萨森斯（Heather Sarsons）——继续进行实证研究，包括现场实验 ，从多个角度探索行为经济学。
行为经济学中的“助推”是什么？
在行为经济学中，“助推”是操纵人们的选择以引导他们做出具体决定的一种方式：例如，将水果放在视线高度或高中食堂收银机附近就是“助推”的一个例子 让学生选择更健康的选择。 助推的一个重要方面是它们不是强制性的：禁止垃圾食品不是助推，也不是惩罚人们选择不健康的选择。
塞勒关于助推的想法在他于 2008 年与前芝加哥大学法律学者、现哈佛大学教授卡斯·桑斯坦 (Cass Sunstein) 合着的《助推：改善有关健康、财富和幸福的决策》一书中得到普及。 企业和政府，包括巴拉克·奥巴马总统领导下的美国政府，已经将泰勒和桑斯坦关于推动政策的想法采纳了。
例如，自动让员工加入 401k 计划，并要求他们选择退出，而不是为他们提供选择加入的机会，这是鼓励更好、更一致的退休储蓄的一个例子。 另一项计划寻求使器官捐赠成为标准做法，要求注册驾驶执照的人表明他们是否愿意捐赠。
塞勒和桑斯坦用来描述围绕助推而设计的情况的正式术语是“自由主义家长主义”——自由主义是因为它保留选择，但家长主义是因为它鼓励某些行为。 用塞勒的话说：“如果你想让人们做某事，就让它变得简单。”
行为经济学术语指南
可用性启发式是指人们在评估特定结果的可能性时通常依赖于容易回忆的信息，而不是实际数据。 例如，如果人们读过有关鲨鱼或熊袭击的报道，他们可能会认为鲨鱼或熊的袭击是一种常见的死亡原因，但这些事件实际上非常罕见。
有限理性是指人们的认知能力、信息和时间都是有限的，从经济学家的角度来看，并不总是能做出“正确”的选择，即使有信息可以指引他们采取特定的行动方针。
这可能是因为他们无法快速综合新信息； 因为他们忽视了这一点，而是选择“跟着自己的直觉走”； 或者因为他们没有时间充分研究所有选项。 该术语由诺贝尔奖获得者、芝加哥大学校友 Herbert A. Simon（AB'36、PhD'43）于 1955 年创造。
有限的自我利益是指人们常常愿意为自己选择不太理想的结果，如果这意味着他们可以支持他人。 慈善事业的捐赠是有限个人利益的一个例子，志愿服务也是如此。 虽然这些是常见的活动，
它们不受传统经济模型的影响，传统经济模型预测人们的行为主要是为了实现自己以及直系亲属和朋友的目标，而不是陌生人的目标。
有限意志力体现了这样一种观点：即使了解了最佳选择，人们通常仍然会优先选择能带来最大短期利益的事物，而不是实现长期目标的渐进进展。 例如，即使我们知道锻炼可以帮助我们实现健身目标，我们也可能无限期推迟，说我们“明天开始”。
损失厌恶是指人们更厌恶损失而不是渴望获得收益。 例如，丢失一张 100 美元的钞票可能比找到一张 100 美元的钞票更痛苦。
前景理论是指卡尼曼和特沃斯基（Kahneman and Tversky，1979）所做的一系列实证观察，他们询问人们如何应对某些涉及输赢的假设情况，从而使他们能够描述人类经济行为的特征。 损失厌恶是前景理论的关键。
沉没成本谬误认为，人们会继续投资一个亏损的项目，仅仅是因为他们已经投入了大量资金，即使这意味着冒着更多损失的风险。
心理账户是指人们根据情况对金钱有不同的看法。 例如，如果天然气价格下降，他们可能会开始购买优质天然气，导致他们最终花费相同的金额，而不是利用较低价格带来的节省。
插画：Ann Yun，芝加哥大学创意学院
Behavioral economics, explained
By Max Witynski
Behavioral economics combines elements of economics and psychology to understand how and why people behave the way they do in the real world. It differs from neoclassical economics, which assumes that most people have well-defined preferences and make well-informed, self-interested decisions based on those preferences.
Shaped by the field-defining work of University of Chicago scholar and Nobel laureate Richard Thaler, behavioral economics examines the differences between what people “should” do and what they actually do and the consequences of those actions.
hat is behavioral economics?
Behavioral economics is grounded in empirical observations of human behavior, which have demonstrated that people do not always make what neoclassical economists consider the “rational” or “optimal” decision, even if they have the information and the tools available to do so.
For example, why do people often avoid or delay investing in 401ks or exercising, even if they know that doing those things would benefit them? And why do gamblers often risk more after both winning and losing, even though the odds remain the same, regardless of “streaks”?
By asking questions like these and identifying answers through experiments, the field of behavioral economics considers people as human beings who are subject to emotion and impulsivity, and who are influenced by their environments and circumstances.
This characterization draws a contrast to traditional economic models that have treated people as purely rational actors—who have perfect self-control and never lose sight of their long-term goals—or as people who occasionally make random errors that cancel out in the long run.
Several principles have emerged from behavioral economics research that have helped economists better understand human economic behavior. From these principles, governments and businesses have developed policy frameworks to encourage people to make particular choices.
Behavioral economics has expanded since the 1980s, but it has a long history: According to Thaler, some important ideas in the field can be traced back to 18th-century Scottish economist Adam Smith.
Smith is often remembered for the concept of an “invisible hand” that guides an overall economy to prosperity if each individual makes their own self-interested decisions—a key concept in classical and neoclassical economics. But he also recognized that people are often overconfident in their own abilities, more afraid of losing than they are eager to win and more likely to pursue short-term than long-term benefits. These ideas (overconfidence, loss aversion and self-control) are foundational concepts in behavioral economics today.
More recently, behavioral economics has early roots in the work of Israeli psychologists Amos Tversky and Daniel Kahneman on uncertainty and risk. In the 1970s and ’80s, Tversky and Kahneman identified several consistent biases in the way people make judgments, finding that people often rely on easily recalled information, rather than actual data, when evaluating the likelihood of a particular outcome, a concept known as the “availability heuristic.” For example, people may think shark or bear attacks are a common cause of death if they’ve read about one such attack, but the incidents are actually very rare.
With “prospect theory,” Tversky and Kahneman also demonstrated that framing and loss aversion influence the choices people make. For example, if presented with an opportunity to win $250 guaranteed or gamble on a 25% chance of winning $1,000 and a 75% chance of winning nothing, most people will choose the sure win. But if presented with the chance to lose $750 guaranteed or a 75% chance to lose $1,000 and a 25% chance to lose nothing, most people will risk losing $1,000, hoping for the slim chance that they will lose nothing at all.
This classic example demonstrates that people are more willing to take a greater statistical risk if it means avoiding a $1,000 loss versus obtaining a $1,000 win, which contradicts expected utility theory. Prospect theory and other work by Tversky and Kahneman continues to inform many areas of behavioral economics research today.
What role have Richard Thaler and behavioral economists at the University of Chicago played in the development of the field?
In the 1980s, Richard Thaler began to build on the work of Tversky and Kahneman, with whom he collaborated extensively. Now the Charles R. Walgreen Distinguished Service Professor of Behavioral Science and Economics at the Booth School of Business, he is today considered a founder of the field of behavioral economics.
Thaler’s research in identifying the factors that guide individuals’ economic decision-making earned him the Sveriges Riksbank Prize in Economic Sciences in Memory of Alfred Nobel in 2017. His ideas stem in part from a series of observations he made in graduate school that led him to believe that people’s behavior deviated from traditional economic models in predictable ways.
For example, Thaler observed that he and a friend were willing to forgo a drive to a sporting event due to a snowstorm because they had been given free tickets. But had they purchased the tickets themselves, they would have been more inclined to go, even though the tickets would have been valued at the same price regardless, and the danger of driving in the snowstorm unchanged. This is an example of the “sunk cost fallacy”—the idea that people are less willing to give up on projects they have personally invested in, even if it means more risk.
Thaler is also known for popularizing the concept of the “nudge,” a conceptual device for leading people to make better decisions. A “nudge” takes advantage of human psychology and a number of other concepts in behavioral economics, including mental accounting—the idea that people treat money differently based on context. For example, people are more willing to drive across town to save $10 on a $20 purchase than $10 on a $1,000 purchase, even though the effort expended and the amount of money saved would be the same.
Thaler and other UChicago economists—including Leonardo Bursztyn, Josh Dean, Nicholas Epley, Austan Goolsbee, Alex Imas, John List, Susan Mayer, Sendhil Mullainathan, Devin Pope, Rebecca Dizon Ross and Heather Sarsons—continue to conduct empirical research, including field experiments, that explore behavioral economics from multiple angles.
What is a “nudge” in behavioral economics?
In behavioral economics, a “nudge” is a way to manipulate people’s choices to lead them to make specific decisions: For example, putting fruit at eye level or near the cash register at a high school cafeteria is an example of a “nudge” to get students to choose healthier options. An essential aspect of nudges is that they are not coercive: Banning junk food is not a nudge, nor is punishing people for choosing unhealthy options.
Thaler’s ideas about nudges were popularized in Nudge: Improving Decisions about Health, Wealth, and Happiness, his 2008 book with former UChicago legal scholar Cass Sunstein, now of Harvard University. Businesses and governments, including the U.S. government under President Barack Obama, have adapted Thaler and Sunstein’s ideas about nudges into policy.
The formal term Thaler and Sunstein use to describe a situation designed around nudges is “libertarian paternalism”—libertarian because it preserves choice, but paternalistic because it encourages certain behavior. In Thaler’s words: “If you want people to do something, make it easy.”
Guide to behavioral economics terms
The availability heuristic refers to the idea that people often rely on easily recalled information, rather than actual data, when evaluating the likelihood of a particular outcome. For example, people may think shark or bear attacks are a common cause of death if they’ve read about one such attack, but the incidents are actually very rare.
Bounded rationality refers to the fact that people have limited cognitive ability, information and time, and do not always make the “correct” choice from an economist’s point of view, even if information is available that would point them toward a particular course of action.
This might be because they cannot synthesize new information quickly; because they ignore it and instead choose to “go with their gut”; or because they don’t have the time to fully research all options. The term was coined in 1955 by Nobel laureate and UChicago alum Herbert A. Simon, AB’36, PhD’43.
Bounded self-interest is the idea that people are often willing to choose a less-optimal outcome for themselves if it means they can support others. Giving to charity is an example of bounded self-interest, as is volunteering. While these are common activities, they are not captured by traditional economic models, which predict that people act mostly to further their own goals and those of their immediate family and friends, rather than strangers.
Bounded willpower captures the idea that even given an understanding of the optimal choice, people will often still preferentially choose whatever brings the most short-term benefit over incremental progress toward a long-term goal. For example, even if we know that exercising may help us obtain our fitness goals, we may put it off indefinitely, saying we will “start tomorrow.”
Loss aversion is the idea that people are more averse to losses than they are eager to make gains. For example, losing a $100 bill might be more painful than finding a $100 bill would be positive.
Prospect theory refers to a series of empirical observations made by Kahneman and Tversky (1979) in which they asked people about how they would respond to certain hypothetical situations involving wins and losses, allowing them to characterize human economic behavior. Loss aversion is key to prospect theory.
The sunk-cost fallacy is the idea that people will continue to invest in a losing project simply because they are already heavily invested, even if it means risking more losses.
Mental accounting is the idea that people think about money differently depending on the circumstances. For example, if the price of gas goes down, they may begin to buy premium gas, leading them to ultimately spend the same amount, rather than taking advantage of the savings offered by the lower price.
