Game theory - fundamental theory, maximin and minimax principles - One Line Questions
1.
In a 3x3 payoff matrix for a zero-sum game, how many pure strategies does each player have? —
3
2.
Consider a game with the following payoff matrix for Player 1: [[3, 1], [2, 4]]. What is the Maximin value for Player 1? —
2
3.
Consider a game with the following payoff matrix for Player 1: [[3, 1], [2, 4]]. What is the Minimax value for Player 2 (minimizing Player 1's payoff)? —
3
4.
Which of the following best describes a 'non-zero-sum game'? —
A game where the sum of payoffs is not necessarily zero; players' gains and losses are not directly opposed.
5.
What does it mean if the Maximin value is strictly less than the Minimax value in a zero-sum game? —
Mixed strategies are required to find the optimal solution.
6.
Which of the following scenarios is best modeled by game theory? —
Two competing companies setting prices.
7.
What is a 'mixed strategy' in game theory? —
A strategy involving a combination of pure strategies with associated probabilities.
8.
What does the term 'pure strategy' refer to in game theory? —
A strategy where a player always chooses a specific action with probability 1.
9.
In the context of game theory, 'fundamental theory' primarily deals with: —
The basic concepts, assumptions, and principles of strategic interaction.
10.
The concept of 'rationality' in game theory implies that players: —
Act in accordance with their preferences and available information to achieve their goals.
11.
In a two-person zero-sum game, what is the sum of the gains and losses of the players? —
Always zero
12.
In a zero-sum game, the payoff matrix for Player 1 is the negative of the payoff matrix for Player 2. This statement is: —
Always true.
13.
If a game has a saddle point, what does this imply about the optimal strategies? —
The optimal strategies are pure strategies.
14.
What does it mean for a game to be 'strictly determined'? —
It has a saddle point, and thus a pure strategy equilibrium.
15.
What is the primary challenge when a game does not have a saddle point? —
Players must resort to mixed strategies, making analysis more complex.
16.
What is the significance of the 'minimax theorem' (for zero-sum games)? —
It states that every zero-sum game has a value, and the Maximin value equals the Minimax value.
17.
Consider a payoff matrix where Player 1 is the row player and Player 2 is the column player. Player 1 wants to maximize their payoff, and Player 2 wants to minimize Player 1's payoff. Player 2 will choose the column that gives the minimum of the column maximums. This is applying the principle of: —
Minimax
18.
What is the main difference between the Maximin and Minimax principles when applied by the same player? —
Maximin is about maximizing minimum gains, Minimax is about minimizing maximum losses.
19.
Consider Player 2 (column player) facing a payoff matrix (where payoffs are for Player 1). Player 2 calculates the maximum payoff Player 1 could receive for each of Player 2's possible columns. Then, Player 2 chooses the column that yields the minimum among these maximum payoffs. This is: —
Minimax strategy
20.
In a two-person zero-sum game, if a saddle point exists, what can be said about the Maximin value and the Minimax value? —
Maximin value equals Minimax value.
21.
The Minimax principle aims to: —
Minimize the opponent's maximum gain.
22.
For a game to have a saddle point, the following condition must be met: —
23.
Consider a payoff matrix where Player 1 is the row player and Player 2 is the column player. Player 1 wants to maximize their payoff, and Player 2 wants to minimize Player 1's payoff (as it's a zero-sum game). Player 1 will choose the row that gives the maximum of the row minimums. This is applying the principle of: —
Maximin
24.
Which principle is used by a player who is uncertain about the opponent's move and wants to ensure the best possible outcome even if the opponent acts in the most unfavorable way for them? —
Maximin
25.
Consider Player 1 (row player) facing a payoff matrix. Player 1 calculates the minimum payoff for each of their possible rows. Then, Player 1 chooses the row that yields the maximum among these minimum payoffs. This is: —
Maximin strategy
26.
What is the fundamental concept that connects the Maximin and Minimax principles in solving zero-sum games? —
The Minimax Theorem
27.
When applying the Maximin principle, a player is acting in a manner that is: —
Pessimistic
28.
When applying the Minimax principle, a player is acting in a manner that is: —
Defensive
29.
If Player 1 uses a mixed strategy, what does this mean? —
Player 1 assigns probabilities to each of their pure strategies and chooses accordingly.
30.
If Player 1's strategy guarantees a payoff of at least $5, and Player 2's strategy guarantees Player 1's payoff is at most $5, what can be concluded? —
The game has a value of $5, and both players are playing optimally.
31.
What is the fundamental assumption about players in most classical game theory models? —
Players are rational and self-interested.
32.
What does the term 'payoff' represent in a game theory context? —
The utility or value a player receives from an outcome.
33.
What is a 'saddle point' in the context of a payoff matrix? —
An element that is the minimum in its row and the maximum in its column.
34.
If the Maximin value of a game is 5 and the Minimax value is 7, what can be concluded? —
The game does not have a saddle point, and players must use mixed strategies.
35.
The Maximin principle provides a player with a strategy that guarantees: —
A minimum payoff level (security level).
36.
What is the 'security level' of a player in game theory? —
The minimum payoff guaranteed regardless of the opponent's strategy.
37.
What is the 'value of the game'? —
The expected payoff when both players play their optimal strategies.
38.
The Minimax principle is associated with which player's perspective in a zero-sum game? —
The player who assumes the opponent will act to minimize their own payoff.
39.
The Maximin principle is associated with which player's perspective in a zero-sum game? —
The player who wants to minimize their maximum possible loss.
40.
What is the relationship between a player's security level and the value of the game? —
For optimal strategies, the security level equals the value of the game.
41.
A payoff matrix is used to represent: —
The payoffs for each player for every possible combination of strategies.
42.
In a game theory context, 'optimal strategy' refers to: —
A strategy that maximizes a player's expected payoff, assuming other players also play optimally.
43.
Which of the following is NOT a characteristic of a rational player in game theory? —
They can perfectly predict the opponent's moves.
44.
If a game has multiple saddle points, what can be said about their values? —
They must all have the same value.
45.
If a game is not strictly determined, what is the implication for the players' optimal strategies? —
They must use mixed strategies.
46.
What is the role of probability in a mixed strategy? —
To assign likelihoods to different pure strategies, making the choice unpredictable.
47.
What is the primary goal when analyzing a game using the Maximin principle? —
To find the strategy that offers the best worst-case scenario.
48.
What is the primary objective of Game Theory? —
To model and analyze strategic interactions between rational decision-makers.
49.
What is the primary goal when analyzing a game using the Minimax principle? —
To find the strategy that minimizes the maximum possible loss (or minimizes the opponent's maximum gain).
50.
For the payoff matrix [[3, 1], [2, 4]], does the game have a saddle point? —
No