Game Theory – Yale (Econ 159)

The course, lectured by Professor Ben Polak, can be found on YouTube or on the Open Yale Courses page.


A game requires a number of components:

Game theory investigates how we can choose between different strategies:

An important meta-parameter is how skilled your opponents are at playing games (i.e their rationality)

Iterative deletion

Nash equilibria

Coordination games

The Candidate-Voter model

The Location model

Mixed strategies

Evolutionary stability

\[(1-\epsilon) u(\hat{s}, \hat{s}) + \epsilon u(\hat{s}, s') > (1-\epsilon)u(s', \hat{s}) + \epsilon u (s', s')\]

Evolutionary stability in mixed strategies

  a b
a 0, 0 2, 1
b 1, 2 0, 0
  H D
H (v-c)/2, (v-c)/2 v, 0
D 0, v v/2, v/2

Midterm exam

I sat the midterm closed-book and under timed conditions. In reality I probably would have tried to give a bit more detail – hence the current marking may be a bit generous, because if I got the right numerical answer I assumed that my method was correct and gave myself all the marks.

Completed Midterm

Sequential games

First movers

Nash equilibria and backward induction


Ultimatums and bargaining

Imperfect information

Strategic investments

Wars of attrition

Repeated games

  A B C
A 4, 4 0, 5 0, 0
B 5, 0 1, 1 0, 0
C 0, 0 0, 0 3, 3

Repeated prisoner’s dilemma

\[\text{temptation to cheat today} \leq \delta \left(\text{value of rewards tomorrow} - \text{value of punishments tomorrow}\right)\]

Asymmetric information