Raul Miller wrote: > I wrote: >> NB. E((1/n-1)\sum (X_i-\bar X)^2 >> (1%eN-1)*+/eX-eM >> >> ... anyways, around here I'm not sure if it's worth >> proceeding, because I worry that either you have made >> assumptions I disagree with or I have made assumptions >> you disagree with or both. > > I should add that I'm not trying to drop the subject -- but the > above J expression would always be zero, regardless of the > underlying data (and regardless of its cardinality), and regardless > of the sampling technique used, which seems to make its use > a problem, in a sequence of equivalences intended to show something > about that magnitude of the cardinality of the sampled data in some > context. >
If you ignore the leading E, I don't see why \sum (x_i-\bar x)^2 is zero for particular sample values. For example, take n=2, x1=0, x2=2, \bar x=1. Then \sum (x_i-\bar x)^2 =2. John ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
