Stat function requests



Hi,
Regarding the distributions with bounded support (e.g., BETADIST, lower end of GAMMADIST and WEIBULL, etc.), would you plz consider *not* emulating Excel, but rather using standard practice? I.e., (1) For distributions, return 0 for x <= lower-bound, and 1 for x >= upper-bound.

(2) Return 0 for all densities (either with respect to Lebesgue measure or counting measure) when x is outside of the support. For example,
BETADIST(x,alpha,beta) would return 0 if x < 0 or x > 1, and
BINOMDIST(n,3,0.5,FALSE) would return 0 iff n <> 0, 1, 2 or 3

(3) Fix the discrete densities to correct what Excel does, namely, truncating doubles, where integers are expected, before evaluation. BINOMDIST(0.5,3,0.5,FALSE) would return 0, not the value returned by BINOMDIST(0,3,0.5,FALSE); and BINOMDIST(n,t,0.5,boolean) would return an error when t not an integer >= 0, rather than blithely truncating it.

I'm a total newbie to this group; plz pardon any etiquette mis-steps I may have made, and definitely let me know of them.
TIA
DaveB




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