A simple math error

Steve Simon


People write in once in a while to correct errors on my webpages. God bless them! I had an error on my What is a P-value? page.

The p-value involved a comparison of two proportions 91% and 82%. I had listed the two fractions as 171 / 240 and 586 / 719. The first fraction is clearly too small to produce 91%. I had actually misread the table in the paper, and the fraction should have been written as 219 / 240.

This has been fixed, but it will take a few days to upload the fix.

I greatly appreciate people who find these things for me. Perhaps the best example of eagle-eyed proof-reading was someone who noted that my bibliographic reference on Stats: Odds ratio versus relative risk (January 9, 2001) to Fahey 1996 should actually be Fahey 1995. That’s an eye for detail that I have to admire.

You can find an earlier version of this page on my original website.