管理策之二決策偏向精品課件

1、Smart Leaders, Foolish Choices: Avoiding Decision Making TrapsLecturer: 姬定中Department Of Business, NIT第1頁(yè)，共63頁(yè)。After this lecture you will be able to knowFramingAvailabilityRepresentativenessAnchoring & AdjustmentOverconfidence第2頁(yè)，共63頁(yè)。 FramingTendency to make different decisions depending on how a

2、problem is presented邊框效應(yīng)（framing effect）是指由于問(wèn)題表述的語(yǔ)境不同，對(duì)同一個(gè)問(wèn)題的兩種邏輯意義上相似的描述最終導(dǎo)致不同的決策判斷的效應(yīng) 第3頁(yè)，共63頁(yè)。4Framing Effect 甲店 現(xiàn)金100元 刷卡加5%乙店 刷卡105元 現(xiàn)金扣5%第4頁(yè)，共63頁(yè)。Cash or Credit?$1.30/gal5 cent discountfor cash.$1.25/gal5 cent chargefor credit.Discount seems negligible, peopleuse credit card.Surcharge isoutrag

3、eouspeople pay cash.gainslosses第5頁(yè)，共63頁(yè)。Example : framingYou go to Shanghai and decide to go to a Shanghai Grand Theatre for a play . You buy a ticket for $100 in the morning, but when you go to the theater that evening, you discover you have lost the ticket. You have plenty of money to buy another

4、one: do you?You go to Shanghai and decide to go to a Shanghai Grand Theatre for a play and tickets cost $100. You go to the theater that evening and when you start to pay for your ticket, you discover you have lost $100. You have plenty of money to buy a ticket: do you?第6頁(yè)，共63頁(yè)。有過(guò)看電影丟了票的經(jīng)歷嗎？想象一下，你已經(jīng)

5、決定去看一場(chǎng)戲劇，每張票的價(jià)格是30 元。當(dāng)你進(jìn)入戲院買(mǎi)票時(shí)，你發(fā)現(xiàn)不知什么時(shí)候你丟了30 元?，F(xiàn)在你還愿意花30元錢(qián)去買(mǎi)票嗎？ （愿意） （不愿意）想象一下，你已經(jīng)決定去看一場(chǎng)戲劇，每張票的價(jià)格是30 元。當(dāng)你進(jìn)入戲院驗(yàn)票時(shí)，你發(fā)現(xiàn)你的票丟了?，F(xiàn)在你愿意花30元錢(qián)重買(mǎi)一張票嗎？ （愿意） （不愿意） 第7頁(yè)，共63頁(yè)。結(jié)果選擇背景丟了錢(qián)丟票愿意85（80%）64（60%）不愿意21（20%）42（40%）第8頁(yè)，共63頁(yè)。結(jié)果的解釋買(mǎi)兩張票時(shí)，我們很容易感到是花了60元看一場(chǎng)電影；而掉了30元和買(mǎi)一張票時(shí)，掉的30元我們并不算做是看電影花的（另外單獨(dú)做賬了）。我們只不過(guò)是將丟失的現(xiàn)金歸結(jié)為倒

6、霉，僅僅使我們感到?jīng)]有原來(lái)那么富有，而不會(huì)直接與看電影相關(guān)聯(lián)。第9頁(yè)，共63頁(yè)。How you frame itDe Martino and his colleagues scanned the brains of 20 volunteers. At the same time, the researchers told the participants they received a sum of money and then repeatedly posed them one of two choices: Keep a chunk of money or gamble, or lose

7、a chunk of money or gamble. As expected, those told they could keep money or gamble were generally leerier of risk. On the other hand, volunteers informed they could lose money or gamble often were more risk-seeking.第10頁(yè)，共63頁(yè)。Framing EffectsRefers to how decision-makers view a problem from a win-los

8、s perspective.The way a problem is framed often influences choices in irrational waysSuppose youve been given $1000 and must choose between:A. Receive $500 more immediatelyB. Flip a coin and receive $1000 more if heads occurs or $0 more if tails occurs第11頁(yè)，共63頁(yè)。Framing Effects (cont)Now suppose youv

9、e been given $2000 and must choose between:A. Give back $500 immediatelyB. Flip a coin and give back $0 if heads occurs or give back $1000 if tails occurs第12頁(yè)，共63頁(yè)。Initial state$1,500Heads (50%)Tails (50%)$2,000$1,000Alternative AAlternative B(Flip coin)Payoffs第13頁(yè)，共63頁(yè)。說(shuō)明我們面對(duì)獲利時(shí)，是風(fēng)險(xiǎn)厭惡者；面對(duì)損失時(shí)，是風(fēng)險(xiǎn)追求者

10、。贏了一點(diǎn)就跑，輸了許多卻還不愿認(rèn)輸。繼續(xù)思考：那人又為什么買(mǎi)6合彩啊？第14頁(yè)，共63頁(yè)。實(shí)驗(yàn)研究表明丟掉10元錢(qián)所帶來(lái)的不愉快感受比撿到10元所帶來(lái)的愉悅感受要強(qiáng)烈得多 。第15頁(yè)，共63頁(yè)?！皳p失10元錢(qián)”和“獲益10元錢(qián)”所帶來(lái)的感受是不一樣的別人的好處是我們難以感受到的，別人的不好卻是讓我們深感痛苦的。第16頁(yè)，共63頁(yè)?！皳p失10元錢(qián)”和“獲益10元錢(qián)”所帶來(lái)的感受是不一樣的所以，孔夫子提醒我們， 滴水之恩，當(dāng)涌泉相報(bào)第17頁(yè)，共63頁(yè)。但丟掉10元錢(qián)所帶來(lái)的不愉快感受比撿到10元所帶來(lái)的愉悅感受要強(qiáng)烈得多 。 一定如此嗎？第18頁(yè)，共63頁(yè)。呵呵上面介紹的研究表明，我們是風(fēng)險(xiǎn)追求

11、者還是風(fēng)險(xiǎn)厭惡者，與許多因素有關(guān)：是面對(duì)盈利，還是虧損；預(yù)期的是收益，還是虧損；剛剛是賭贏了，還是賭輸了；是男的，還是女的；這一點(diǎn)還與偏執(zhí)與否及程度有關(guān)第19頁(yè)，共63頁(yè)。面對(duì)收益真是風(fēng)險(xiǎn)厭惡者嗎？是風(fēng)險(xiǎn)厭惡者還是風(fēng)險(xiǎn)追求者，還決定于概率的大?。韩@利的概率太小時(shí)，人們也更多地成為風(fēng)險(xiǎn)追求者。 所以我們會(huì)買(mǎi)6合彩?。〉?0頁(yè)，共63頁(yè)。所以我們是風(fēng)險(xiǎn)追求者還是風(fēng)險(xiǎn)厭惡者，與許多因素有關(guān)：是面對(duì)盈利，還是虧損；收益或虧損是否是預(yù)期的；剛剛是賭贏了，還是賭輸了；是男的，還是女的；收益或損失的概率是大還是?。粋鹘y(tǒng)的設(shè)想人是理性的，沒(méi)有系統(tǒng)的厭惡?？裳芯勘砻?，這一切是變化的，而且是在不同層次上變化的。第

12、21頁(yè)，共63頁(yè)。我們是穩(wěn)定不變的嗎？我們有時(shí)喜歡賭，有時(shí)又不喜歡賭。有時(shí)比較謹(jǐn)慎，有時(shí)又比較冒險(xiǎn)，愿意“賭大的”。 第22頁(yè)，共63頁(yè)。如何來(lái)評(píng)價(jià)本周虧3000元？你可能想到的是：哎，倒霉，虧了3000元！嘿，上周還賺了10000元；本周只虧了3000元。為什么感受不一樣??！第23頁(yè)，共63頁(yè)。Framing (from Plous, 1993)Wording issues in questionnairesDo you get headaches frequently? (2.2/wk)Do you get headaches occasionally? (0.7/wk)Suggests

13、that the way we frame problems or issues can have significant impact on the information we gather and on the decisions taken (Hart)第24頁(yè)，共63頁(yè)。Framing (from Plous, 1993)Overcoming framing effects:Evaluate the quality of your assumptions and existing frames (appropriate? realistic? how do they direct y

14、our attention?)Seek other opinions (e.g. people who continually disagree with you )Temporarily adopt other peoples (e.g. competitors, employees, top management) viewpoint, to see how they might be framing the situation第25頁(yè)，共63頁(yè)。可得性啟發(fā)請(qǐng)問(wèn)： K在英文單詞里，是更常出現(xiàn)在第一個(gè)字母位置，還是第三個(gè)字母位置？第三個(gè)字母位置是K的詞是起首字母為K的詞的三倍第26頁(yè)，共63

15、頁(yè)。Availability HeuristicWe are biased by information:that is easier to recallvivid, well-publicized or recentmore salient (our attention is drawn to it)All of this makes it more available to us 所謂“可得性啟發(fā)(availability heuristic)” ，是說(shuō)最易被想起的事件通常被認(rèn)為最普遍。相應(yīng)地人們對(duì)他們不易記憶的事物則認(rèn)為是不常發(fā)生的 。第27頁(yè)，共63頁(yè)。Availability Ten

16、dency to judge the likelihood of an occurrence on the basis of the extent to which other like instances can easily be recalled.Ex. Are there more words beginning with “R,” or having “R” as third letter?Most will say beginning, simply b/c it is easier to think of examples for this possibilityActually

17、 more words with an “R” as third letter第28頁(yè)，共63頁(yè)。VividnessVividness: how concrete or imaginable something is, or how emotionally stimulating (Hart & Bing)Example from a drunk-driving trial simulation“On his way out the door, Smith staggered against a serving table, knocking a bowl to the floor.”“On

18、his way out the door, Smith staggered against a serving table, knocking a bowl of salsa dip to the floor and splattering tomato salsa on the white carpet.”18 hours later, significantly more subjects given the second scenario judged Smith to be guilty (remembered vivid information more easily, based

19、judgement on it)(Plaus, 1993)第29頁(yè)，共63頁(yè)。Availability in useEase of recall is often a good clue to likelihood of occurrence but not always.Beware of information that comes too easily to mind (because it is vivid, salient, recent ) you might be overlooking something more subtle but crucial!第30頁(yè)，共63頁(yè)。問(wèn)題

20、某女，31歲，單身，坦誠(chéng)、非常聰明。專(zhuān)業(yè)哲學(xué)，在學(xué)生時(shí)代積極關(guān)心歧視問(wèn)題和社會(huì)公平問(wèn)題，同時(shí)參加了反核示威。 請(qǐng)回答，哪一個(gè)可能性更大：A:“該女是銀行出納員”；B:“該女是銀行出納員和女權(quán)運(yùn)動(dòng)者” 。第31頁(yè)，共63頁(yè)。我們知道，男女比例大致相等那么，請(qǐng)估計(jì)在有6個(gè)孩子的家庭中，男(B)女(G)兒童出生順序?yàn)镚BGBBG和BGBBBB的比例，哪個(gè)更高？ （B代表男孩，G代表女孩）第32頁(yè)，共63頁(yè)。典型（代表）性啟發(fā)某女，31歲，單身，坦誠(chéng)、非常聰明。專(zhuān)業(yè)哲學(xué)，在學(xué)生時(shí)代積極關(guān)心歧視問(wèn)題和社會(huì)公平問(wèn)題，同時(shí)參加了反核示威。 請(qǐng)快速回答，哪一個(gè)可能性更大：A:“該女是銀行出納員”；B:“該女是

21、銀行出納員和女權(quán)運(yùn)動(dòng)者” 。為什么那么多人選擇了B呢？第33頁(yè)，共63頁(yè)。我們知道，男女比例大致相等那么，請(qǐng)估計(jì)在有6個(gè)孩子的家庭中，男(B)女(G)兒童出生順序?yàn)镚BGBBG和BGBBBB（B代表男孩，G代表女孩）的比例，哪個(gè)高？結(jié)果大多數(shù)被試估計(jì)前者遠(yuǎn)高于后者。為什么會(huì)這樣呢？要知道從機(jī)會(huì)來(lái)說(shuō)，兩者的概率應(yīng)是相等的啊。就因?yàn)镚BGBBG更典型也更有代表性：更能代表整個(gè)人口中的比例，而且看起來(lái)更隨機(jī)。第34頁(yè)，共63頁(yè)。RepresentativenessRepresentativeness:Tendency to be overly influenced by stereotypes in

22、 making judgments about the likelihood of occurrences.example: Robert wears glasses, speaks quietly, and read a lot. Is it more likely that Robert is a librarian or a farmer?Most will pick librarian, b/c (A) Roberts characteristics, are more consistent with a librarian (B)第35頁(yè)，共63頁(yè)。ExamplesYou flip

23、a coin 6 times. Given that flipping a fair coin is random ( a 50 -50 chance or a head or tail). Which of the following outcomes is most likely or probable?A.HHTHTTB.HHHTTTBoth are equally likely the probability is same on each toss.第36頁(yè)，共63頁(yè)。Representativeness we use this shortcut as a way to judge

24、the degree to which an individual object, person or event is representative of a specific category, group, etc.The use of this heuristic typically means that we underuse the base rate information that may be available第37頁(yè)，共63頁(yè)。RepresentativenessSubjects were told that personality tests had been done

25、 on a group consisting of 30 engineers and 70 lawyers. They were then given 5 short descriptions and told that these had been chosen at random from the 100.Here is one such description:第38頁(yè)，共63頁(yè)。Is Jack a Lawyer or an Engineer?Jack is a 45 year-old man. He is married with three children. He is gener

26、ally conservative, careful and ambitious. He shows little interest in political and social issues and spends his spare time on his hobbies. The subjects were then asked the following question:In your opinion, what is the probability that the person described is an engineer, on a scale of 0 to 100?第3

27、9頁(yè)，共63頁(yè)。Example 2 the use of stereotypesThere are 100 people in a room, 70 of them are lawyers, 30 are engineers.Bill is randomly selected from this room. What is the probability he is a lawyer? Dick is a 30-year-old man. He is married with no children. A man of high ability and high motivation he p

28、romises to be very successful. He is well liked by his colleagues.Jack is 45-years-old, and married with 3 children. He tends to be conservative, careful, and ambitious. He shows little interest in political and social interests, and enjoys carpentry, sailing, and mathematical puzzles.第40頁(yè)，共63頁(yè)。Repr

29、esentativeness:Insensitivity to probability base ratesK & T found that peoples ratings of whether Jack was an engineer were virtually unaffected by the base rate information (70% Lawyers or 30% Engineers)The more “engineer-specific” information was given (e.g. he likes carpentry, puzzles), the highe

30、r the probability ratings that Jack was an engineer.In general, the more detail people are given, the more they ignore the base-rates第41頁(yè)，共63頁(yè)。Ignoring Base RatesWhy do more hotel fires start on the 1st ten floors than the second ten floorsFrank is a meek and quiet man whose only hobby is playing ch

31、ess. He was near the top of his college class and majored in philosophy. Is he a librarian or a business man?Youve watched a coin toss come up heads 5 times in a row. If you bet $100 on the next toss, would you choose heads or tails?第42頁(yè)，共63頁(yè)。Representativeness heuristic: ConclusionSimilarity (analo

32、gy) & probability can be related, so representativeness can be a good heuristic most of the time.But, like availability, it leads to systematic, predictable biases for certain tasks.We are flawed probability estimators, insensitive to base rates and sample sizes and easily influenced by detailed sce

33、narios; we are poor estimators of outcomesThis affects our choice of alternatives in decision makingBut knowing this can help us avoid some of the pitfalls第43頁(yè)，共63頁(yè)。請(qǐng)大致估計(jì)請(qǐng)把答案寫(xiě)在相應(yīng)問(wèn)題后面的（ ）內(nèi)。第44頁(yè)，共63頁(yè)。請(qǐng)大致估計(jì)有多少非洲國(guó)家是聯(lián)合國(guó)成員。這里要告訴你的是，肯定在1個(gè)以上。 第45頁(yè)，共63頁(yè)。請(qǐng)大致估算1x2x3x4x5x6x7x8第46頁(yè)，共63頁(yè)。請(qǐng)大致估計(jì)有多少非洲國(guó)家是聯(lián)合國(guó)成員。這里要告訴你

34、的是，肯定在100個(gè)以?xún)?nèi)。 第47頁(yè)，共63頁(yè)。請(qǐng)大致估算8x7x6x5x4x3x2x1第48頁(yè)，共63頁(yè)。錨定與調(diào)整Anchoring & Adjustment 為什么在這兩個(gè)小測(cè)驗(yàn)中，人們的估計(jì)會(huì)因表述的稍許差別而極大地不同呢？是1與100 （或1、2、3等前幾個(gè)數(shù))影響了人們的估計(jì)：人們的估計(jì)被錨定在最初的這樣一個(gè)數(shù)附近。第49頁(yè)，共63頁(yè)。Anchoring & Adjustment (Tversky and Kahneman, 1974)Tendency to be influenced by an initial figure, even when the information

35、is largely irrelevant We judge size or quantity based on an initial anchor value plus an adjustmentStage 1: Person starts with initial idea of answer (“anchor”)“Ball park” (general) estimate.Anchor may be suggested by perception, experience or by something in the environment.Stage 2; Person adjusts

36、away from initial anchor to arrive at final judgement.This suggests that you can bias a persons estimate if you provide the initial anchor第50頁(yè)，共63頁(yè)。Anchoring & Adjustment (Tversky and Kahneman, 1974)Some everyday examplesEstimating salary for a new employee:Base it on past employees salary and adjus

37、t from there (regardless of changes to the job or new requirements, etc.)Car salesman attempting to anchor you to the “windscreen price” on carGood bargainers know this第51頁(yè)，共63頁(yè)。52行為決策理論 Daniel Kahneman Amos Tversky Nobel Prize 2019 (1937-2019)第52頁(yè)，共63頁(yè)。Anchoring & AdjustmentSunk Cost Effects公司給了一張價(jià)

38、值300元的明星演唱會(huì)門(mén)票，碰上大暴雨，去不去？?jī)r(jià)值300元的票是自己買(mǎi)的，碰上大暴雨，去不去？第53頁(yè)，共63頁(yè)。54沉沒(méi)成本新產(chǎn)品研發(fā)計(jì)劃，據(jù)悉競(jìng)爭(zhēng)對(duì)手已經(jīng)開(kāi)發(fā)出來(lái)，如果做下去，很大幾率要損失500萬(wàn)。但有很小的幾率可以獲利2500萬(wàn)。做或不做？新產(chǎn)品研發(fā)計(jì)劃， 已經(jīng)投資500萬(wàn)，再丟50萬(wàn)就可上市。據(jù)悉競(jìng)爭(zhēng)對(duì)手已經(jīng)開(kāi)發(fā)出來(lái)，如果做下去，很大幾率要損失500萬(wàn)。但有很小的幾率可以獲利2500萬(wàn)。做或不做？第54頁(yè)，共63頁(yè)。Another aspect of anchoringConfirmation bias:Paying more attention to information th

39、at confirms ones own beliefs, regardless of the research (selective perception) (Hart & Bing)Our initial beliefs do not easily shift (are anchored), despite potentially disconfirming evidenceExamples: Studies of the effects of smoking, caffeine, global warming, HRT, etc.Whatever study supports our i

40、nitial position we view as “more convincing”, “better designed”, “definitive” .第55頁(yè)，共63頁(yè)。Anchoring & Adjustment (Tversky and Kahneman, 1974)In order to counteract this bias:Be aware of the problem of anchoring choose a different anchor and see the effect on the solution/decision e.g. avoid sticking too close to previous years numbers when making company forecastsProvide a range, not a single-point valueWork with multiple anchorsapproach key estimates from several starting points (e.g. best-case/worst-case scenarios)