Problem 126 Answer

Strategy of z After x and y bid the $1000 range will be divided into three intervals. Call A the interval from $1000 to the lesser of the two prior bids, B the interval between the two prior bids, and C the interval between $2000 and the greater of the two prior bids. If max(B,C)/(B+C) > (A/$1000) then bid $.01 more than x or y, depending on which will give you the greater interval. If max(B,C)/(B+C) < (A/$1000) then bid $1000.

Strategy of y Call x's bid X.

If x bids more than $1750 then y should bid X - X*(sqr((2000-X)/1000)-(2000-x)/2000)+ $.01 .

If x bids less than $1750 then y should bid 2X-$1999.99 .

Strategy of x x should bid $1750.01 .

Michael Shackleford, A.S.A., 10/20/1998