Reading 5 The Behavioral Finance Perspective Flashcards
Indifference curve shows
The indifference curve shows the marginal rate of substitution, or the rate at which a person is willing to give up one good for another, at any point.
If the two items are perfect substitutes, then the individual is willing to trade one for the other in a fixed ratio; then, the indifference curve is a line with a constant slope reflecting the marginal rate of substitution.
If the two items are perfect complements, then the curve would be L-shaped.
Bayes’ formula
Bayes’ formula is a mathematical rule explaining how existing probability beliefs should be changed given new information: P(A|B) = [P(B|A)/P(B)] P(A) where: P(A|B) = conditional probability of event A given B. It is the updated probability of A given the new information B. P(B|A) = conditional probability of B given A. It is the probability of the new information B given event A. P(B) = prior (unconditional) probability of information B. P(A) = prior probability of event A, without new information B. This is the base rate or base probability of event A.
Examples of six operations in the editing phase
Codification: Prospects are coded as (gain or loss, probability; gain or loss, probability; …) such that the probabilities initially add to 100 percent or 1.0.
Combination: Prospects are simplified by combining the probabilities associated with identical gains or losses. For example, a prospect initially coded as (250, 0.20; 200, 0.25; 200, 0.15; 150, 0.40) will be simplified to (250, 0.20; 200, 0.40; 150, 0.40).
Segregation: The riskless component of any prospect is separated from its risky component. For example, a prospect initially coded as (300, 0.8; 200, 0.2) is decomposed into a sure gain of (200, 1.0) and a risky prospect of (100, 0.8; 0, 0.20). The same process is applied for losses.
The above operations are applied to each prospect separately. The following operations are applied to two or more prospects:
Cancellation: Cancellation involves discarding common outcome probability pairs between choices. For example, the pairs (200, 0.2; 100, 0.5; 20, 0.3) and (200, 0.2; 300, 0.4; –50, 0.4) are reduced to (100, 0.5; 20, 0.3) and (300, 0.4; –50, 0.4).
Simplification: Prospects are likely to be rounded off. A prospect of (51, 0.49) is likely to be seen as an even chance to win 50. Also, extremely unlikely outcomes are likely to be discarded or assigned a probability of zero.
Detection of Dominance: Outcomes that are strictly dominated are scanned and rejected without further evaluation.
efficient market
the market where prices incorporate and reflect all available and relevant information
Behavioral biases of individual investors can be categorized as?
Behavioral biases can be categorized as cognitive errors or emotional biases.
Bounded rationality is
Bounded rationality is proposed as an alternative to the assumptions of perfect information and perfect rationality.
Bounded rationality assumes that individuals’ choices are rational but are subject to limitations of knowledge and cognitive capacity.
Bounded rationality is concerned with ways in which final decisions are shaped by the decision-making process itself.
Fundamental anomalies
A fundamental anomaly is an irregularity that emerges when one considers a stock’s future performance based on a fundamental assessment of the stock’s value.
The apparent size and value stock anomalies may be a function of incomplete models being used in testing for inefficiency rather than actual anomalies.
Neuro-economics and its more interesting results
Neuro-economics is an emerging field of study relevant to understanding how people make economic decisions under uncertainty. Neuro-economics attempts to explain investor behavior based on the functioning of the brain.
Perhaps some of the more interesting insights result from examining chemical levels in the brain.
A Behavioral Approach to Asset Pricing
Shefrin proposes a behavioral approach to asset pricing using models, which Shefrin terms behavioral stochastic discount factor-based (SDF-based) asset pricing models.
The stochastic discount factor to reflect this bias is a function of investor sentiment relative to fundamental value.
The discount rate captures the effects of the time value of money, fundamental risk, and sentiment risk.
Shefrin proposes that the dispersion of analysts’ forecasts serves as a proxy for the sentiment risk premium in the model.
The basic axioms of utility theory
The basic axioms of utility theory are completeness, transitivity, independence, and continuity:
- Completeness assumes that an individual has well-defined preferences and can decide between any two alternatives.
- Transitivity assumes that, as an individual decides according to the completeness axiom, an individual decides consistently.
- Independence also pertains to well-defined preferences and assumes that the preference order of two choices combined in the same proportion with a third choice maintains the same preference order as the original preference order of the two choices
- Continuity assumes there are continuous (unbroken) indifference curves such that an individual is indifferent between all points, representing combinations of choices, on a single indifference curve.
REM, definition
- REM will try to obtain the highest possible economic well-being or utility given budget constraints and the available information about opportunities, and he will base his choices only on the consideration of his own personal utility, not considering the well-being of others except to the extent this impacts REM’s utility.
- REM is a rational, self-interested, labor-averse individual who has the ability to make judgments about his subjectively defined ends.
- REM also strives to maximize economic well-being by selecting strategies contingent on predetermined, utility-optimizing goals on the information that he possesses as well as on any other postulated constraints.
- REM tries to achieve discretely specified goals to the most comprehensive, consistent extent possible while minimizing economic costs.
BFMA, definition
Behavioral finance macro (BFMA) considers market anomalies that distinguish markets from the efficient markets of traditional finance. BFMA questions the efficiency of markets.
Friedman-Savage vs. Traditional utility function
- Friedman-Savage utility function* is characterized by an inflection point where the function turns from concave to convex - risk-seeking (conves) utility function for gains and a risk-avarese (concave) utility function for losses. This type of function explains why people may take low-probability, high payoff risks (e.g., out-of-money options) ahile at the same time insuring against low-probability, low-payoff risks (e.g. earthquake insurance).
- Traditional finance theory* assumes risk aversion (concave utility function) at all levels of wealth, which would lead to rejection of all gambles having a non-positive expected return.
The factors that are not considered under the Utility theory
Utility theory should also consider such other factors as risk aversion, probability, size of the payout, and the different utility yielded from the payout based on the individual’s circumstances.
Risk evaluation is dependent on what?
Risk evaluation is reference-dependent, meaning risk evaluation depends in part on the wealth level and circumstances of the decision maker.
six operations in the editing process, the ultimate purpose of the evaluation phase
Depending on the number of prospects, there may be up to six operations in the editing process: codification, combination, segregation, cancellation, simplification, and detection of dominance.
The ultimate purpose behind editing is to simplify the evaluation of choices available by reducing the choices to be more thoroughly evaluated. People use editing when making choices because of cognitive constraints.
Forms of market efficiency
Fama proposes three forms of market efficiency: the weak form, the semi-strong form, and the strong form.
Weak-form market efficiency assumes that all past market price and volume data are fully reflected in securities’ prices. Thus, if a market is weak-form efficient, technical analysis will not generate excess returns.
Semi-strong-form market efficiency assumes that all publicly available information, past and present, is fully reflected in securities’ prices. Thus, if a market is semi-strong-form efficient, technical and fundamental analyses will not generate excess returns.
Strong-form market efficiency assumes that all information, public and private, is fully reflected in securities’ prices. Thus, if a market is strong-form efficient, even insider information will not generate excess returns.
Perfect Rationality, Self-Interest, and Information
- Rationality is not the sole driver of human behavior. At times, it is observed that the human intellect is subservient to such human emotions as fear, love, hate, pleasure, and pain.
- Perfect self-interest is the idea that humans are perfectly selfish.
- It is impossible, however, for every person to enjoy perfect knowledge of every subject. In the world of investing, there is nearly an infinite amount to learn and know, and even the most successful investors don’t master all disciplines.
Decision theory is
Decision theory is concerned with identifying values, probabilities, and other uncertainties relevant to a given decision and using that information to arrive at a theoretically optimal decision. Decision theory is normative, meaning that it is concerned with identifying the ideal decision.
Prospect theory definition
Kahneman and Tversky introduce prospect theory as an alternative to expected utility theory. Prospect theory describes how individuals make choices in situations in which they have to decide between alternatives that involve risk (e.g., financial decisions) and how individuals evaluate potential losses and gains.
Two phases to make a choice in prospect theory
In prospect theory, based on descriptive analysis of how choices are made, there are two phases to making a choice: an early phase in which prospects are framed (or edited) and a subsequent phase in which prospects are evaluated and chosen.
Technical anomaly
A technical anomaly is an irregularity that emerges when one considers past prices and volume levels. Technical analysis encompasses a number of techniques that attempt to forecast securities prices by studying past prices and volume levels. Common technical analysis strategies are based on relative strength and moving averages, as well as on support and resistance.
Prospect theory vs. expected utility theory
Prospect theory has been proposed as an alternative to expected utility theory. Prospect theory assigns value to gains and losses (changes in wealth) rather than to final wealth, and probabilities are replaced by decision weights.