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Message Posted: Wed, 06 Jun 2007 @ 09:27:00 GMT

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Subj:   Re: Minimal Stats Sampling and a well-informed
From:   Geoffrey Rommel

  The number of distinct values will end up being extrapolated upwards, depending on the percentage of rows sampled. If 2% of the rows were sampled, then you could expect to see about 50 times more distinct values in the produced estimate....  

Carrie, this seems odd to me. Two percent is a large sample -- far more than is needed for a 99% confidence level. Why doesn't the sampler simply accept what it finds? Is it because of a fear that the sample isn't "truly random"?

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