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Old 09-July-2007, 05:01 PM
JohnW JohnW is offline
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Quote:
Originally Posted by Revsmile View Post
If the above is correct, then adding the rainfalls in each group, could, because of the central limit theorem result in approximately normal variates. If the original daily data are variates with finite means and standard deviation then the normal distribution should be assumed. However there are only 29 of them, so the statistical power will not be very good.
My emphasis above. You're right in general, but rainfall data are often highly skewed (days and days with no rain at all, and a couple of days of complete deluge). I would be reluctant to just assume normality without testing it.