Lecture_09_Decision Making Flashcards
Decision Making
Assessing and making choices between various OPTIONS
- Evaluated on their CONSEQUENCES
Judgment
Estimating the PROBABILITY of various EVENTS
- Evaluated on their accuracy
- E.g. “Which one is a more likely cause of death – car accident or lung cancer?”
Normative Theories
How people SHOULD make decisions
Descriptive Theories
How people ACTUALLY make decisions
Ideal, Rational Decisions
Based on Economics
- Make decisions based on LOGICAL reasoning
- Calculate and choose the option that maximizes EXPECTED VALUE
Expected Value
Expected value = (value of a given outcome) x (probability of that outcome)
Which one is an optimal decision?
A) 50% chance of gaining 50 baht
B) 10% chance of gaining 100 baht
A) E(X) = (0.5) x 50 = 25 baht
B) E(X) = (0.1) x 100 = 10 baht
- So, the “optimal” decision is A), because it has a greater expected value
- Prospect theory
Subjective Value
Based on Psychology
-The same option can have different values!
- Depends on the person and the situation (subjective value)
- Calculate and choose the option that maximizes Expected utility
- For that particular person, in that particular situation
Expected Utility
Expected utility = (utility of a given outcome) x (probability of that outcome)
Which one is the rational choice?
A) One KFC set for 100 baht
B) Fifty KFC sets on sale for 4,000 baht
B) is more rational but, with subjective value, people may choose A) more
Principle of transitivity in rational decision making
- If A > B and B > C
- Then A > C
Predictably Irrational Decisions
People don’t always choose the “optimal”, logical choice…
- Not random choices
- Consistent, but irrational (sub-optimal) choices
Decision Making Under Risk
Rationally, people should always choose the option that maximize chances of gains, and minimize chances of losses
Prospect Theory
- People are much more sensitive to potential losses than potential gains (loss aversion)
- “Losses loom larger than gains”
- So, people are willing to take risks to avoid losses
Heuristics
- Framing bias/effect
- Availability heuristic
- Representativeness heuristic