In article <email@example.com>, RichD <firstname.lastname@example.org> wrote:
> Ocasionally I come across somethign called log > normal, and I wonder, what is the purpose? > The normal distribution is natural, but the log of that, > seems unnatural, and unintuitive. > > Can anyone elaborate on its use? > > -- > Rich
Theoretically, the range of a normal distribution is: all real numbers. If we have some random quantity that cannot, by definition, be negative, then of course its distribution cannot be normal. Sometimes in those cases it turns out that log-normal distribution is a good model.