Re: Minimum number of cases for a correlation?

Glucoboost wrote:
I am reviewing a piece of research in which a correlation of .6 has
been found between two variables. The scatterplot is okay. However, the
N is 12. I remember reading somewhere that an N of 50 was the minimum
required for a correlation.

Is an N of 12 just too small for a correlation?

No, it's OK. i.e. you can calculate the correlation, and it's a summary of the data The confidence intervals might be a bit wide, that's all.

If the scatterplot is presented as well, then I wouldn't worry: people can judge for themselves what's going on.

Bob

--
Bob O'Hara

Dept. of Mathematics and Statistics
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