cor shows only NA or 1 for correlations - Why?

Question

I\'m running cor() on a data.framewith all numeric values and I\'m getting this as the result:

       price exprice...
price      1         


        

Answer 1

The 1s are because everything is perfectly correlated with itself, and the NAs are because there are NAs in your variables.

You will have to specify how you want R to compute the correlation when there are missing values, because the default is to only compute a coefficient with complete information.

You can change this behavior with the use argument to cor, see ?cor for details.