Sorry, I obviously did not state clearly what the problem is (thanks Daniel):
1. minor problem: cor() does return different types of variables for methods "kendall" and pearson (matrix vs. scalar) when pairwise.complete.obs is selected. 2. major problem: cor() does return with an error if both x and y are matrices with method="kendall" when pairwise.complete.obs is selected and one column of one of the two matrices is completely NA. This does not happen for method "pearson". Regards, Hilmar Hilmar Berger <hilmar.berger <at> imise.uni-leipzig.de> writes: > > Hi all, > > I'm not quite sure if this is a feature or a bug or if I just fail to > understand > the documentation: > > If I use cor() with pairwise.complete.obs and method=pearson, the > result is a > scalar: > > ->cor(c(1,2,3),c(3,4,6),use="pairwise.complete.obs",method="pearson") > [1] 0.9819805 > > The documentation says that > " '"pairwise.complete.obs"' only works with the '"pearson"' method > for 'cov' and 'var'." > > Thus, I guess that cor() should work for pairwise.complete.obs and > method = > "kendall", or am I misinterpreting that statement ? > > -> c(1,2,3),c(3,4,6),use="pairwise.complete.obs",method="kendall") > [,1] > [1,] 1 > > Now the result is a matrix with dimensions (1,1) - strange enough. > > Note that when I use "all.obs" or "complete.obs" I get a scalar for > method > kendall, too. > > It gets worse if one tries to calculate the correlation between the > columns of > two matrices (i.e. cor(x,y) with x and y being a matrix). Then > > -> c=matrix(c(1,2,3,3,4,5),nrow=3,ncol=2) > -> d=matrix(c(2,3,4,NA,NA,NA),nrow=3,ncol=2) > -> cor(c,d,use="pairwise.complete.obs",method="pearson") > [,1] [,2] > [1,] 1 NA > [2,] 1 NA > > -> cor(c,d,use="pairwise.complete.obs",method="kendall") > Error: 'x' is empty (*translated from german error message*) > > The behavior is reproducible in R 2.4.1 and 2.6.1 (WinXP). I noticed > that in > 2.7.0 something was fixed in cor() related to "complete.obs" handling > - would > that fix my problems ? > > Any suggestions ? > > Thanks, > Hilmar > > ______________________________________________ > R-help <at> r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide > http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. > > ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
