Linear Model of Data in Matrix Form

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I have data in matrix form from a parameter scan of a food web
simulation. (The matrix entry M[i,j] gives the variable of interest
for a web size i and connectance j.) How would I find an equation
expressing the variable of interest to web size and connectance? Can
lm() do it?

Thanks,
Jane Shevtsov

suppose your size and connectance vectors were sizevec and connvec.
Then something like

dimnames(M) <- list(sizevec,connvec)
library(reshape)
X <- melt(M)
lm(value~X1+X2)

  will do it.
	
  Mini example:

z <- matrix(1:9,nrow=3,dimnames=list(1:3,4:6))
library(reshape)

Loading required package: plyr

Attaching package: 'reshape'

The following object(s) are masked from 'package:plyr':

    round_any

str(melt(z))

'data.frame':	9 obs. of  3 variables:
 $ X1   : int  1 2 3 1 2 3 1 2 3
 $ X2   : int  4 4 4 5 5 5 6 6 6
 $ value: int  1 2 3 4 5 6 7 8 9
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