MATH TUTORIAL Binomial Distribution:The bottom line -r- <x>=Np <x2>=p1-p)N+p2W2 o=(<k2>-<k>2)2=[p1-p)N]V2 http://keral2008.blogspot.com/2008/10/derivation-of-mean-and-variance-of.html Network Science:Random Graphs MATH TUTORIAL Binomial Distribution: The bottom line Network Science: Random Graphs http://keral2008.blogspot.com/2008/10/derivation-of-mean-and-variance-of.html P(x) = N x æ è ç ö ø ÷p x (1- p) N -x < x >= Np < x 2 >= p(1- p)N + p 2 N 2 sx = (< k 2 > - < k > 2 ) 1/ 2 =[p(1- p)N] 1/ 2