On 23 Nov 1999 09:16:42 -0800, [EMAIL PROTECTED] (Bob Hayden)
wrote:
> Here is a query from someone I met in a hallway a couple weeks ago.
> I'm not sure I even understand the question. If anyone out there
> recognizes anything familiar in this scenario, you might respond to
> JMC -- not to me or the list.
- well, here is a short comment, anyway... also e-mailed, since Forte
Agent can do that quite conveniently.
> ----- Forwarded message from Jennifer Mary Collins -----
>
> The problem is that the data I use, which is hurricane numbers, deals
> with small numbers. Hence they are poisson distributed, when one
> considers the other criteria to be poisson.
You might as well say, Hurricanes disrupt little fishes and therefore
the distribution is poisson (== "fishes" in French). -- Nonsequitur.
Having small numbers has little or nothing to do with being Poisson.
Having *counts* is where Poisson usually comes in, but the example
which is given doesn't show a count, anywhere.
Further, the question, as near as I can make it, has to do with some
average being different in 5 years of X, vs 5 years of not-X. That
is ordinarily considered as a difference in means, which everyone
would test by a t-test -- to compare the difference to zero. But she
wants to compare the ratio to 1.0. I suppose you could develop
tests based on the ratio of the means, but what is the purpose? My
pedantic guess is that she has not been taught any inferential
statistics, and happened to take a step into a difficult direction in
trying to invent a test from scratch; else she would have come up
with the t-test.
Hope this helps.
--
Rich Ulrich, [EMAIL PROTECTED]
http://www.pitt.edu/~wpilib/index.html
