Behavioral Finance Flashcards
What is Traditional and Behavioral Finance
Traditional finance
- How people should behave
- Assumes rational, risk-adverse, and selfish
Behavioral finance
- How people actually behave
- Can result in biases and markets may not be efficient
- Could be risk-adverse, neutral, or seeking
Investor Risk Types
Risk-Averse - Concave
Risk-Neutral - straight
Risk-Seeking - Convex
Friedman-Savage (Forms an S)
Concave at low/high wealth
Convex at medium wealth
Challenges to Rational Economic Men (REM)
Traditional finance
- Decision making can be flawed by lack of information
- Can have conflicts that prioritize short-term (spending) goals over long-term (saving) goals
- Lack of perfect knowledge (most crucial)
Utility Theory (TF)
- Satisfaction based on level of wealth
- Diminishing marginal return: satisfaction increases at a slower rate
- Convexed indifference curve: slower rate of substitution
Decision Theory (TF)
Making the ideal decision when the decision maker is fully informed, mathematically able, and rational.
Bounded Rationality
Have a capiticty on knowledge and nothing is perfect
Accept things that satisfy but are not perfect
Example
I have excess funds. I want the funds to be backed by the government so I went to the bank. The rate seems acceptable, so I move forward. I didn’t do any other research.
Prospect Theory (BF)
Definition: Perceived gain/loss drives satisfaction (NOT level)
- Depends on starting point
- Decisions are made in stages
- Decision weights are subjective (NOT rational)
Consequences:
Takes gains quickly, hold onto losses
Low probability events are over-weighted
Prospect Theory Stages (BF)
Phase 1: Editing
Proposals are made and ranked
Could lead to isolation effect (presentation and complexity affect decisions)
Phase 2: Evaluation
Focus on loss aversion
Investors place more weight for a loss than a gain (fear)
Prospect Theory Behavior
- People overreact to small probabilities and underreact to large ones
- Results in the S shape
- Gains = risk-adverse, losses = risk-seekers
a. explains why people over-concentrate positions
Traditional Finance and Prospect Theory Assumptions
Knowledge
Utility
Decision Making
Risk
Portfolio Construction
Traditional Finance Prospect Theory
Knowledge Perfect Capacity limitations
Utility Maximization Satisfice
Decision Making Full rational Congnitive limits
Risk Risk-adverse Depends on gain/loss
Portfolio Constr. Markets are efficient Alternative theories
Focus on asset allocation
Efficient Market Hypthosesis (EMH)
Follows traditional finance
3 types of efficiency
- weak-form: prices reflect all past data
- cannot use technical analysis
- semi-strong: prices reflect all past data and public info
- cannot use technical or fundamental analysis
- strong-form: prices reflect all past data, public, and non-public
- cannot use technical or fundamental analysis or insider trading
EMH Support and Challenges
Support
Events can trigger abnormalities. (e.g. stock split) which allows for people to make predictions.
Large cap stocks may be more efficient than others
Challenges
Small and value effects
Anomalies (Fundamental & Calendar)
Behavioral Finance Portfolio Construction Types
- Consumption & savings - can people have self control and save?
- Behavioral asset pricing - adds a sentiment premium (dispersion of analysts forecasts) to CAPM. Wider dispersion = higher discount rate
- Behavioral Portfolio Theory (BPT) - Build a portfolio of layers with different types of risks (all built separately and correlation is ignored)
- Adaptive Markets Hypothesis (AMH) - Adapt your process or die (satisfice driven). Active managagement works
Cognitive Errors vs Emotional Baises
Cognitive Errors (Thinking)
Faulty reasoning
Can be corrected
Emotional Biases
Based on impulses or intuition
Must be accomodated
(Someone can have both)
Cognitive Errors Types
Belief Perseverance
- Representativeness
- Illusion of control
- Conservatism
- Confirmation bias
- Hindsight bias
Conservatism
Type: Cognitive
Definition: rationally form an initial view but won’t change it
Consequences
Hold investments too long
slow to update view
Confirmation Bias
Type: Cognitive
Definition: look for or distort information to support current view
Consequences
Under-diversified
Concentration in employer stock
Representativeness Bias
Type: Cognitive
Definition: past classification will persist and new information is based on past experience
Consequences
- Hold on to or buy recent winners
- Sell or avoid recent losers
- Excessive turnover