Lecture 1 Flashcards
Define Game Theory
Game theory is the conceptualization of decisionmaking where decisions are shaped by simultaneous actions.
Define finite strategic games.
- Finite number of players.
- For each player, a non empty action set. (which could be different for each player.)
- For each player, preferences represented by utility functions.
Use the Moriarty and Sherlock Holmes as an example. Define the actions, and their respective utilities.
Actions: {Dover, Canterbury}
Players: {Sherlock, Moriarty}
Utility…
Define the concept of strategy.
A strategy is not an action, it is a complete set of actions which the player might take given different context. It can be represented by a probability distribution.
How are individual preferences characterized for each player?
The expected utility over all strategies of all players.
Define a Nash Equilibrium.
A strategy profile s is an NE if
v_j(s*j, s*-j) >= v_j(s_j, s_-j) for all j
with v_j being individual preferences and s_j being individual strategies.
What is the golden rule of mixed equilibrium?
If players mix, they must be indifferent across all outcomes.
If there exists a NE in a Zero Sum Game. What must be true about the individual preferences of each player?
That the min(s_i) max(s_j) {v_j(s_j, s_i)} = max(s_j) min(s_i){v_j(s_j, s_i)}
Give on specificity of optimal strategies in Zero Sum Games.
If a strategy is optimal in a ZSG, then such a strategy is also optimal in ZSG where utility is monotonically transformed.
Define the bargaining problem in the context of cooperative Game Theory.
- A compact set of outcomes X
- Two continuous utility functions.
- An outcome d in the set X called the disagreement outcome. Both players prefer all outcomes to the disagreement outcome.
What is an important feature of ZSG?
One player’s win is the other’s loss. u_1(s) = -u_2(s)
What does the Nash BArgaining Solution outcome maximize?
The product of added utilities w.r.t the status-quo outcome.
Prove the if of Von Neuman Proposition.
Prove the “and only if” of the Von Neuman Propositon.
Prove the if of the following poposition.