> (Fishman's book is from 1978, and I don't know the > meaning of "double precision" in that context relative to > ours.)
"Double precision" in 1978 most likely meant 64 bits. Likewise today. ----- Original Message ----- From: Brian Schott <[EMAIL PROTECTED]> Date: Saturday, August 9, 2008 7:53 Subject: Re: [Jprogramming] general Gamma distribution To: Programming forum <[email protected]> > Let me add what may be obvious, but I cannot be > sure. When generating Poisson random variates using the > routines we have been discussing, people are > usually interested in cases for which the mean, lambda, is > quite modest, because when lambda gets larger, the > Poisson distribution becomes so symmetric (unskewed) as to > be almost identical to the normal distribution. So it is > with small lambda, that the skewness of the distribution > would suggest threshholding as Raul or Fishman are > suggestiong and I think small lambda is also the case for > which "double precision" is needed, not for large lambda. > > (Fishman's book is from 1978, and I don't know the > meaning of "double precision" in that context relative to > ours.) > > So I wonder if more could be done to study both the > threshholding and the precision requirements for > small lambda. > > Would the use of x: produce more precision and could > that be done exclusively in the definition of possible? If > so, how? > > possible=: (^-y) +/\@:* 1 */\@, y&% ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
