# Incorrect mean and SD of Pascal distribution?

In https://wiki.geogebra.org/e... it is written:

"The Pascal distribution models the number of failures before the nth success in repeated mutually independent Bernoulli trials, each with probability of success p."

And this definition is in alignment with the definition used in program R (see "Details" in documentation http://stat.ethz.ch/R-manua...)

If X ~ Pascal(n, p) and X is a number of failures, n is a number of successes and p is a probability of one success, then the mean of X should be n(1-p)/p and the variance of X should be n(1-p)/(p^2) (as defined in R's manual). Standard deviation (SD) is the square root of variance. It seams that GeoGebra calculates the mean as np/(1-p) and the standard deviation as sqrt(np/((1-p)^2) which is not the mean and the SD of failures.

Are these calculations intentional or is it a bug?

Thanks, fixed for v455

mi ingles hace que yo no entienda bien qué diferencia hay entre Pascal(n,p) del post anterior y esta pagina de la wiki

https://en.wikipedia.org/wi...

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(Redirected from Pascal distribution)

¿en qué son diferentes? ¿está errónea la wiki?

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