Quiz 1 bonus question 11• “At least half of the people taking this quiz will label this statement ‘true’.”

– 9 out of 9 answered “true”!– Everyone was right!– If everyone had answered “false”, that would have been right, too…

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pure-strategy equilibria

# true

• A (symmetric) mixed-strategy equilibrium: everyone plays “true” with probability ½

Quiz 1 bonus question 12• “At least half of the people taking this quiz will label this statement ‘false’.”

– 5 out of 9 answered “false”– Those 5 were wrong, because they made the statement true.– Of course, there had to be at least 5 wrong answers (why?), so overall the class did as well as it could have…

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pure-strategy equilibria

# false

• A (symmetric) mixed-strategy equilibrium: everyone plays “true” with probability ½