Re: ANALYZE sampling is too good - Mailing list pgsql-hackers

From Greg Stark
Subject Re: ANALYZE sampling is too good
Date
Msg-id CAM-w4HMrZTy8F56hbGpSEyrQ9hwiuuTm1pm6amh=MgK1yKhzrg@mail.gmail.com
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In response to Re: ANALYZE sampling is too good  (Greg Stark <stark@mit.edu>)
List pgsql-hackers
On Mon, Dec 9, 2013 at 6:54 PM, Greg Stark <stark@mit.edu> wrote:
>
> This "some math" is straightforward basic statistics.  The 95th
> percentile confidence interval for a sample consisting of 300 samples
> from a population of a 1 million would be 5.66%. A sample consisting
> of 1000 samples would have a 95th percentile confidence interval of
> +/- 3.1%.

Incidentally I got this using an online sample size calculator. Google
turns up several but this one seems the easiest to use:
http://www.raosoft.com/samplesize.html


-- 
greg



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