Descriptive theories of rationality Flashcards
<p>Expected value theory</p>
<p>Your long-run “average”
What is to be expected if you choose an option an infinite number of times
EV = p(occurring) * (potential outcome) + p (not occurring) * (potential outcome)
</p>
<p>Saint Petersburg Paradox</p>
<p>EV (game) = .5(2.00) + .25(4.00) +
.125(8.0) ….
= 1.00 + 1.00 + 1.00..
= INFINITE AMOUNT OF MONEY
</p>
<p>
| Fechner’s Law</p>
<p> Psychological intensity is a logarithmic f(n) of physical intensity Just noticeable differences</p> <p> </p> <p> </p>
Utility Curve implies _____ ______
risk aversion
Concave Utility function: Gamble 1: What do you prefer
A: $100
B. .5 ($200)
.5 (0)
Concave utility function explains ____ _______
A: $100
Risk aversion
Expected Utility Theory is a _________ theory of behavior that does not explain ____?______; but how people….
Normative theory of behavior
Does not explain how people behave
how they SHOULD behave if they followed certain requirements of rational decision making
What are the six principles of the expected utility theory?
principle 1: Ordering principle 2: Dominance Principle 3: Cancellation principle 4: Transitivity (EU Axiom) principle 5: Independence Principle 6: Invariance (distribution of probabilities across alternatives)
Principle 1 of the EU:
Ordering
Principle 1: Ordering
Rational decision-makers should be able to compare alternatives
comparability Axiom of EU
Principle 2 of the EU:
Dominance
Principle 2: Dominance
Car A is $ 15,000 and gets 35 MPG
Car B is $20,000 and gets 28 MPG
A = much better (it dominates) B
Principle 3 of the EU:
Cancellation
Principle 3: Cancellation
Decisions are made by comparing differences.
Similarities cancel out
Independence Axiom (EU)
Principle 4 of the EU:
Transitivity (EU Axiom)
Principle 4: Transitivity (EU Axiom)
If A > B and B > C, then A > C
Principle 5 of the EU:
Independence
Principle 5: Independence
The preference between two option must not be affected by a third outcome that is equal to both options)
pertains to well-defined preferences and assumes that two gambles mixed with a third one maintain the same preference order as when the two are presented independently of the third one
Principle 6 of the EU:
Invariance (Distribution of probabilities across alternatives)
Principle 6: Invariance (Distribution of probabilities across alternatives)
A decision maker should not be affected by the way that the alternatives are presented
Ex) Choose between:
A two-stage lottery that pays out $100 if you win both stages (p= .50 to win at each stage), OR
25% chance to win $100 in a once-and-done lottery
Define: Axiom
a statement or proposition that is regarded as being established, accepted, or self-evidently true.
Expected Utility Theory Axioms:
EU established explicit axioms that underlie _______ _______ _______
When axioms are satisfied, a ________ ________ can be associated with each consequence.
Rational decision-making
Numerical measurement