4. Some types of resource conflicts can be modeled using the following game. Two players would each like to capture a valuable resource, worth R. Each player must choose a strategy from {Amicable, Belligerent}. If one player chooses Belligerent while the other chooses Amicable, the first will walk away with the resource, leaving nothing for the other player. If they both choose Amicable, the resource will be split equally between them. If they both choose Belligerent, the resource will also be split equally between them, but they will each suffer a cost C. P2 Amicable Belligerent P1 Amicable Belligerent R/2, R/2 R, O 0, R R/2-C, R/2-C 4.1. What NEs in pure strategies will the game have for the case where a) R/2 > C, b) R/2 < C and c) R/2 = C? 4.2. Find a Nash equilibrium (NE) in fully (strictly) mixed strategies for this game using the indifference property. Assume that R and C are configured so that a fully mixed NE exists.

Two hunters are on a stag hunt. They split up in the forest and each have two strategies: hunt for a stag (S), or give up the stag hunt and instead hunt for rabbit (R). If they both hunt for a stag, they will succeed and each earn a payoff of 9. If one hunts for stag and the other gives up and hunts for rabbit, the stag hunter receives 0 and the rabbit hunter 8. If both hunt for rabbit then each receives 7. Compute all Nash equilibria for this game, called 'The Stag Hunt', depicted below. Which of these equilibria do you think is most likely to be played? Why? S R S 9,9 8,0 R 0,8 7,7

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7. Solving for dominant strategies and the Nash equilibrium Suppose Felix and Janet are playing a game in which both must simultaneously choose the action Left or Right. The payoff matrix that follows shows the payoff each person will earn as a function of both of their choices. For example, the lower-right cell shows that if Felix chooses Right and Janet chooses Right, Felix will receive a payoff of 7 and Janet will receive a payoff of 4. Felix Left Right Left 6,3 3,3 Janet Right 6,4 7,4 The only dominant strategy in this game is for to choose The outcome reflecting the unique Nash equilibrium in this game is as follows: Felix chooses and Janet chooses

8. Solving for dominant strategies and the Nash equilibrium Suppose Tim and Alyssa are playing a game in which both must simultaneously choose the action Left or Right. The payoff matrix that follows shows the payoff each person will earn as a function of both of their choices. For example, the lower-right cell shows that if Tim chooses Right and Alyssa chooses Right, Tim will receive a payoff of 3 and Alyssa will receive a payoff of 6. Tim Left Left 5, 6 Right 4, 2 Alyssa Right 5,5 3,6 The only dominant strategy in this game is for to choose The outcome reflecting the unique Nash equilibrium in this game is as follows: Tim chooses and Alyssa chooses

Consider the following game where two players have to decide if they want to buy a movie ticket or a baseball ticket. They have the highest payoffs when they both buy tickets to the same activity, but must decide simultaneously what to buy without knowing what the other person will do.  a. Does either player have a dominant strategy? b. How many equilibria does this game have? c. Is this an example of a prisoner’s dilemma? Explain. d. What will be the outcome if your friend buys their ticket first and you can observe their choice?

3. The following is an interpretation of the rivalry between the United States (USA) and the Soviet Ünion (USSR) during the cold war. Each side has the choice of two strategies: Aggressive and Restrained. The payoff table is given as follows: USSR Restrained Aggressiveness Restrained 4,3 1,4 USA Aggressiveness 3,1 2,2 a) Consider this game when the two countries move simultaneously. Find all pure strategy Nash equilibria. b) Next consider three alternative ways in which the game could be played with sequential moves: (i) The USA moves first and the USSR moves second. (i) the USSR moves first and the USA moves second. (i) The USSR moves first, and the USA moves second, but the USSR has a further move after the USA moves. For each case, draw the game tree and find the subgame-perfect Nash equilibrium. c) What are the key strategic issues (commitment, credibility and so on) for the two countries. (Note: Be concise. Your answer should not exceed 300 words].

Consider the following game. You will roll a fair, 6-sided die either once or twice. You decide whether to do the second roll after you see how the first one lands. The payoff is $n, where n is the outcome of the last roll. For example, if the first roll lands 4 and the second lands 2, you win $2. If you only do one roll and it lands 4, you win $4. Suppose you make your decision about whether to go for a second roll based on expected monetary value. Then you will go for a second roll if (and only if) the first roll lands x or lower. What is x?

7. Solving for dominant strategies and the Nash equilibrium Suppose Carlos and Deborah are playing a game in which both must simultaneously choose the action Left or Right. The payoff matrix that follows shows the payoff each person will earn as a function of both of their choices. For example, the lower-right cell shows that if Carlos chooses Right and Deborah chooses Right, Carlos will receive a payoff of 5 and Deborah will receive a payoff of 1. Carlos Deborah Left Left 4,4 Right 2,4 Right 6,7 5,1 The only dominant strategy in this game is for to choose The outcome reflecting the unique Nash equilibrium in this game is as follows: Carlos chooses and Deborah chooses

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