On 8/16/07, Darren Cook <[EMAIL PROTECTED]> wrote: > Apologies for the off-topic post, but I know lots of people here are > interested in statistics and algorithms. > > Calculating the mean of a stream of numbers [1] is easy: just keep track > of the sum and the count, and divide at the end. But what about the > median? I think I always need to buffer at least half the numbers, but > does anyone know for sure, or know a clever algorithm [2]?
You'll have to remember all numbers. If you've seen a_0 < a_1 < a_2 < ... < a_n so far, then for any i, 0<=i<=n, you'll have to ouput a_i after an additional (n-i) values less than a_0, and i values greater than a_n. regards, -John _______________________________________________ computer-go mailing list [email protected] http://www.computer-go.org/mailman/listinfo/computer-go/
