[R] linear regression by column

[David Winsemius]

On Feb 29, 2012, at 1:53 PM, Filoche wrote:

> Hi everyone.
>
> I have a DF with the first column being my independant variable and  
> all
> other columns the dependent variables.
>
> Something like:
>
> x	y1	y2	y3
> ...	...	...	...
> ...	...	...	...
>
> What I'm trying to do is to perform a linear model for each of my  
> "y". It is
> pretty simple with loops, but I'm trying to vectorize it using  
> *apply*.
>
> For instance, I tried something like:
>
> apply(DF, 1, function(DF){lm(DF[,1] ~ Band1[,2:5])})

apply( DF[2:5], 2, function(x){lm(DF[,1] ~ x)})

You need to use the variable name that you created in the function  
call and loop over columns, not rows.

>
> But apparently it does not work.

For about four or five reasons.

> .

David Winsemius, MD
West Hartford, CT