Distance matrix based on correlation coefficient
On Tue, 2010-07-20 at 23:35 +0300, Jari Oksanen wrote:
On 20/07/10 22:42 PM, "Gavin Simpson" <gavin.simpson at ucl.ac.uk> wrote:
On Tue, 2010-07-20 at 12:12 -0700, Dragos Zaharescu wrote:
I would much appreciate if someone would enlighten me on how to calculate a distance matrix based on correlation coefficient (Spearman)? The simple correlation matrix seems not to work.
1 - cor(dat) ## dissimilarity
Actually the canonical transformation to distance is sqrt(2-2*cor(dat)). Cheers, Jari Oksanen
Of course, thanks Jari. That 1 - bit was total rubbish, not even acknowledging that cor could be negative. Not sure what came over me; I blame the heat here in London ;-) Hangs head in shame. G
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