# [R] Selecting individuals to maximize the correlation of two variables

Enrico Schumann es at enricoschumann.net
Sat Jan 11 15:38:27 CET 2014

```On Fri, 10 Jan 2014, 汤靖 <mr_tangjing at hotmail.com> writes:

> Hi,
> Maybe it is not directly related to R but sine many are statistical experts so I post it here for help:
>
> I have two variables (say x and y) of length n. Now the cor(x,y) is close to 0. I need to find the subset in {1,.. n} so that the correlation between x and y using the subset data is maximized. A trivial choice would be selecting 2 individuals only so that cor(x,y) =1. As the size of the subset increases, cor(x,y) will go down to 0, but I am assuming the best correlation for each size of the subsets would not be monotonically decreasing.
>
> Any idea of how to find the solution?
>
> Thanks,
> Jing
>
>

Hi Jing,

in chapter 1 of the NMOF manual I discuss a very similar problem; perhaps
it helps you (but it's a draft only...)

http://enricoschumann.net/NMOF.htm#NMOFmanual

--
Enrico Schumann
Lucerne, Switzerland
http://enricoschumann.net

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