Bubble Investors: What Were They Thinking? Ravi Dhar, Yale SOM William N. Goetzmann SOM/HBS

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Gervais Bridges
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1 Bubble Investors: What Were They Thinking? Ravi Dhar, Yale SOM William N. Goetzmann SOM/HBS

2 Behavioral Finance Cognition matters. Hard to get into the mind of the investor. Let s ask them.

3 Polling Investor Thinking Benefits: Contextual, actual decisions. Drawbacks: depend on framing and recollection retrospective biases. Bob Shiller s Investor Confidence Surveys. Ivo Welch s surveys of finance professors. MIT studies of investor physiology.

4 This Study A class-action action lawsuit. Point of law: class definition hinged in part on whether investors believed the market was efficient. Also, whether they conditioned decision upon the stock price. Our role: Assess beliefs about efficiency. Assess motivations for trade. Consider the general and the particular.

5 Results Evidence inconsistent with belief in the Efficient Market Theory. Strong belief in the value of personal and professional equity research. Price trends matter to valuation. Belief in over-reaction reaction to news. Rational bubble beliefs.

6 Efficient Market Beliefs Weak form: past price trends not useful. Semi-strong: public news rapidly and fairly impounded in prices. Stocks are not over-valued valued or under- valued Personal research

7 Methodology Telephone questionnaire Just before no-call lists Investors who bought telecommunications stock X 11/1999 to 12/2. NOT employees. Stock near its peak in 11/1999

9 Target America Affluent pool, philanthropic giving 156,319 called (very expensive!) 16,733 spoke to us and qualified (amazing number of buyers of the stock) 845 completed the survey (5% response rate) High standards of monitoring, randomization of questions etc.

10 Sample Bias? Buyers of individual stocks. Speculators by definition? Buyers of telecom in late 1999-early 2. Speculators by definition? Wealthy individuals educated? Inference about broad population.

11 How likely is that the price of an individual stock is higher or lower than its true value? Extremely likely Very likely Somewhat likely Not too likely Not at all likely Don't know

12 Which factor that you rely on in determining whether the price of a stock differs from its intrinsic value is the single most important? The long term trend in the stock's price, say its price over the past 3 years The short term trend in the stock's price, say its price over the past 3 to 6 months The 52-week high and 52-week low price for the stock Opinion of my broker/financial advisor My own research on company's financial information

13 If the price of the stock is close to its 52- week high price, does it indicate to you that the stock is Very over-valued Valued about the right amount Very undervalued Somewhat over-valued Somewhat undervalued Don't know

14 If the price of a stock is close to its 52-week low price, does it indicate to you that the stock is... Very over-valued Valued about the right amount Very undervalued Somewhat over-valued Somewhat undervalued Don't know

15 If the long term trend in the stock price, say its price over the past 3 years, shows an steady increase,, does it indicate to you that the stock is Very over-valued Valued about the right amount Very undervalued Somewhat over-valued Somewhat undervalued Don't know

16 If the long term trend in the stock price, say its price over the past 3 years, shows an steady decrease,, does it indicate to you that the stock is Very over-valued Valued about the right amount Very undervalued Somewhat over-valued Somewhat undervalued Don't know

17 2 From you own research on a company, how likely are you to identify stocks that are either undervalued or overvalued? Extremely likely Somewhat likely Not at all likely Very likely Not too likely Don't know/ it depends

18 Thinking in general about stocks prices and how they change in response to the release of news and public announcements about a company, do you think the price of a stock tends to Over react a good deal React about the right amount Under-react a good deal Over react somewhat Under-react somewhat Don't know/ it depends

19 How often have you purchased a stock that at the time seemed over valued but you purchased it any way because you thought that the price was likely to go even higher? Very often Sometimes Never Often Rarely Don't know/ it depends

20 Thinking back to the FIRST time when you made your purchase, did you believe at the time of purchase that the price of stock X was... Very over-valued Valued about the right amount Very undervalued Somewhat over-valued Somewhat undervalued Don't know

21 Which one reason that you rely on in determining that Stock X was overvalued at the time of the FIRST purchase was the single most important? The long term trend in the stock's price, say its price over the past 3 years The short term trend in the stock's price, say its price over the past 3 to 6 months The 52-week high and 52-week low price for the stock Opinion of my broker/financial advisor My own research on company's financial information

22 Did you purchase Stock X anyway because you expected the price to continue go higher, to diversify you portfolio or for some other reason? I expected the price to continue to go higher To diversify my portfolio Other Don't know/ No Answer

23 A "bubble" is defined as a time when stock prices are considerably above their true value. In your opinion, was the recent peak in telecom share prices...? Definitely a bubble Probably not a bubble Don't know/no Answer Probably a bubble Definitely not a bubble

24 Conclusions This group holds beliefs contrary to EMH. Beliefs consistent with a model of personal research identifying under-valued and over-valued valued securities. Signs of contrarianism. Direct admission of bubble investing.

The Efficient Market Hypothesis

Efficient Market Hypothesis (EMH) 11-2 The Efficient Market Hypothesis Maurice Kendall (1953) found no predictable pattern in stock prices. Prices are as likely to go up as to go down on any particular