Re: st: product function

[Roger Newson <roger.newson@kcl.ac.uk>]

At 11:43 25/05/04 -0500, Dimitriy V. Masterov wrote:
> I would like to plot the probability that two people share a birthday as a
> function of the number of people in the room n. The formula is
>
>         1-product((366-i)/365,i,1,n)
>
> In TeX, it would be
>
>         1-\dprod\limits_{i=1}^{n}\frac{366-i}{365}.
>
> If I have a variable n={1,...,50}, how can I define the product within
> Stata? There does not seem to be math function that can do this.
One way might be to calculate logs and then to use the -sum()- function.

Roger


--
Roger Newson
Lecturer in Medical Statistics
Department of Public Health Sciences
King's College London
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