User talk:24.47.176.251

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I believe there is an error in the pdf function listed, it is missing a -(1/2) in the exponent of the exp!!! —The preceding unsigned comment was added by 24.47.176.251 (talk) 19:02, 11 December 2006 (UTC).

Well, scanning the article I find the first mention of the pdf, and clearly the factor of −1/2 is there, where it belongs:
The probability density function of the normal distribution with mean μ and variance σ2 (equivalently, standard deviation σ) is a Gaussian function,
f(x;\mu,\sigma) = \frac{1}{\sigma\sqrt{2\pi}} \, \exp \left( -\frac{(x- \mu)^2}{2\sigma^2} \right) = {1 \over \sigma} \varphi \left( \frac{x - \mu}{\sigma} \right),
where
\varphi(x)=\frac{1}{\sqrt{2\pi\,}} e^{-x^2/2}
is the density function of the "standard" normal distribution, i.e., the normal distribution with μ = 0 and σ = 1.
similarly I find the factor of −1/2 in all the other places in the article where the density is given. Did I miss one? If so, please be specific as to where it is found. Michael Hardy 21:28, 11 December 2006 (UTC)