经济学 关于纳什均衡Two people are engaged in a joint project. If each

经济学 关于纳什均衡
Two people are engaged in a joint project. If each person i puts in
the effort xi , a nonnegative number equal to at least 0 and at most
1, which costs her c (xi) ; the outcome of the project is worth f(x1;
x2) : The worth of the project is split equally between the two
people, regardless of their effort levels.
Find its Nash equilibria when f
(x1, x2) = 3x1x2; c(xi)
= xi2 for i = 1,2
Hint: find the best response of each player to the
other player’s effort, and cross the best responses. There is only one solution
(x1*,x2*)

Is there a pair of effort
levels that would yield both players higher payoffs than the Nash equilibriumeffort levels? How do we call this type of situation?