投资学：Chap012.ppt

1、INVESTMENTS | BODIE, KANE, MARCUS Copyright 2011 by The McGraw-Hill Companies, Inc. All rights reserved. McGraw-Hill/Irwin CHAPTER 12 Behavioral Finance and Technical Analysis INVESTMENTS | BODIE, KANE, MARCUS 12-2 Behavioral Finance Conventional Finance Prices are correct; equal to intrinsic value.

2、 Resources are allocated efficiently. Consistent with EMH Behavioral Finance What if investors dont behave rationally? INVESTMENTS | BODIE, KANE, MARCUS 12-3 The Behavioral Critique Two categories of irrationalities: 1. Investors do not always process information correctly. Result: Incorrect probabi

3、lity distributions of future returns. 2. Even when given a probability distribution of returns, investors may make inconsistent or suboptimal decisions. Result: They have behavioral biases. INVESTMENTS | BODIE, KANE, MARCUS 12-4 Errors in Information Processing: Misestimating True Probabilities 1. F

4、orecasting Errors: Too much weight is placed on recent experiences. 2. Overconfidence: Investors overestimate their abilities and the precision of their forecasts. 3. Conservatism: Investors are slow to update their beliefs and under react to new information. 4. Sample Size Neglect and Representativ

5、eness: Investors are too quick to infer a pattern or trend from a small sample. INVESTMENTS | BODIE, KANE, MARCUS 12-5 Behavioral Biases Biases result in less than rational decisions, even with perfect information. Examples: 1.Framing: How the risk is described, “risky losses” vs. “risky gains”, can

6、 affect investor decisions. INVESTMENTS | BODIE, KANE, MARCUS 12-6 Behavioral Biases 2. Mental Accounting: Investors may segregate accounts or monies and take risks with their gains that they would not take with their principal. 3. Regret Avoidance: Investors blame themselves more when an unconventi

7、onal or risky bet turns out badly. INVESTMENTS | BODIE, KANE, MARCUS 12-7 Behavioral Biases 4. Prospect Theory: Conventional view: Utility depends on level of wealth. Behavioral view: Utility depends on changes in current wealth. INVESTMENTS | BODIE, KANE, MARCUS 12-8 Figure 12.1 Prospect Theory INV

8、ESTMENTS | BODIE, KANE, MARCUS 12-9 Limits to Arbitrage Behavioral biases would not matter if rational arbitrageurs could fully exploit the mistakes of behavioral investors. Fundamental Risk: “Markets can remain irrational longer than you can remain solvent.” Intrinsic value and market value may tak

9、e too long to converge. INVESTMENTS | BODIE, KANE, MARCUS 12-10 Limits to Arbitrage Implementation Costs: Transactions costs and restrictions on short selling can limit arbitrage activity. Model Risk: What if you have a bad model and the market value is actually correct? INVESTMENTS | BODIE, KANE, M

10、ARCUS 12-11 Limits to Arbitrage and the Law of One Price Siamese Twin Companies Royal Dutch should sell for 1.5 times Shell Have deviated from parity ratio for extended periods Example of fundamental risk INVESTMENTS | BODIE, KANE, MARCUS 12-12 Figure 12.2 Pricing of Royal Dutch Relative to Shell (D

11、eviation from Parity) INVESTMENTS | BODIE, KANE, MARCUS 12-13 Limits to Arbitrage and the Law of One Price Equity Carve-outs 3Com and Palm Arbitrage limited by availability of shares for shorting Closed-End Funds May sell at premium or discount to NAV Can also be explained by rational return expecta

12、tions INVESTMENTS | BODIE, KANE, MARCUS 12-14 Bubbles and Behavioral Economics Bubbles are easier to spot after they end. Dot-com bubble Housing bubble INVESTMENTS | BODIE, KANE, MARCUS 12-15 Bubbles and Behavioral Economics Rational explanation for stock market bubble using the dividend discount mo

13、del: S&P 500 is worth $12,883 million if dividend growth rate is 8% (close to actual value in 2000). S&P 500 is worth $8,589 million if dividend growth rate is 7.4% (close to actual value in 2002). gk D PV 1 0 INVESTMENTS | BODIE, KANE, MARCUS 12-16 Technical Analysis and Behavioral Finance Technica

14、l analysis attempts to exploit recurring and predictable patterns in stock prices. Prices adjust gradually to a new equilibrium. Market values and intrinsic values converge slowly. INVESTMENTS | BODIE, KANE, MARCUS 12-17 Technical Analysis and Behavioral Finance Disposition effect: The tendency of i

15、nvestors to hold on to losing investments. Demand for shares depends on price history Can lead to momentum in stock prices INVESTMENTS | BODIE, KANE, MARCUS 12-18 Trends and Corrections: The Search for Momentum Dow Theory 1.Primary trend : Long-term movement of prices, lasting from several months to

16、 several years. 2.Secondary or intermediate trend: short- term deviations of prices from the underlying trend line and are eliminated by corrections. 3.Tertiary or minor trends: Daily fluctuations of little importance. INVESTMENTS | BODIE, KANE, MARCUS 12-19 Figure 12.3 Dow Theory Trends INVESTMENTS

17、 | BODIE, KANE, MARCUS 12-20 Trends and Corrections: Moving Averages The moving average is the average level of prices over a given interval of time. Bullish signal: Market price breaks through the moving average line from below. Time to buy Bearish signal: When prices fall below the moving average,

18、 it is time to sell. INVESTMENTS | BODIE, KANE, MARCUS 12-21 Figure 12.5 Moving Average for HPQ INVESTMENTS | BODIE, KANE, MARCUS 12-22 Trends and Corrections: Breadth Breadth: Often measured as the spread between the number of stocks that advance and decline in price. INVESTMENTS | BODIE, KANE, MAR

19、CUS 12-23 Sentiment Indicators: Trin Statistic Trin Statistic: Ratios above 1.0 are bearish advancingnumber advancingvolume decliningnumber decliningvolume trin . . . . INVESTMENTS | BODIE, KANE, MARCUS 12-24 Sentiment Indicators: Confidence Index Confidence index: The ratio of the average yield on

20、10 top-rated corporate bonds divided by the average yield on 10 intermediate-grade corporate bonds. Higher values are bullish. INVESTMENTS | BODIE, KANE, MARCUS 12-25 Sentiment Indicators: Put/Call Ratio Calls are the right to buy. A way to bet on rising prices Puts are the right to sell. A way to b

21、et on falling prices A rising ratio may signal investor pessimism and a coming market decline. Contrarian investors see a rising ratio as a buying opportunity! INVESTMENTS | BODIE, KANE, MARCUS 12-26 Warning! It is possible to perceive patterns that really dont exist. Figure 12.8A is based on the re

22、al data. The graph in panel B was generated using “returns” created by a random-number generator. Figure 12.9 shows obvious randomness in the weekly price changes behind the two panels in Figure 12.8 INVESTMENTS | BODIE, KANE, MARCUS 12-27 Figure 12.8 Actual and Simulated Levels for Stock Market Prices of 52 Weeks INVESTMENTS | BODIE, KANE, MARCUS 12-28 Figure 12.9 Actual and Simulated Changes in Stock Prices for 52 Weeks