[R] cor and missing values. Bug?

[Peter Dalgaard]

"Robert W. Baer, Ph.D." <rbaer at atsu.edu> writes:

> > Not to put too fine a point on it, but did you consider checking the
> > NEWS file for the most recent version (1.9.0,
> > http://cran.r-project.org/src/base/NEWS)?
> >
> >     o   The cor() function did not remove missing values in the
> >         non-Pearson case.
> 
> 
> There is still something a little strange in version 1.9.0. What  is the
> source of the discrpancy between cor() and cor.test()?

One ranks x and y before removing missing values, the other one
removes them first and then ranks. It is not really desirable, but a
better solution is nontrivial (esp. in the "pairwise.complete.obs"
case) and we did document it in ?cor:

                  Notice also that the ranking is (currently) done
     removing only cases that are missing on the variable itself,
     which may not be what you expect if you let 'use' be '"complete.obs"'
     or '"pairwise.complete.obs"'.


-- 
   O__  ---- Peter Dalgaard             Blegdamsvej 3  
  c/ /'_ --- Dept. of Biostatistics     2200 Cph. N   
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