NA as a result of using GLM
On Mon, 2009-06-15 at 12:46 +0200, poleteiep34 wrote:
Hi all!
Maybe someone could help me with the following. I know this hasn't
directly to do with ecology but I'm also using glm.
I have a list of 16 genes and 10 samples. The samples are of two
types, 4 Ctrl and 6 Diseased. If,
labelInd<-as.factor(c(rep("0",4),rep("1",6)))
genes.glm<-glm(labelInd ~ ., family=binomial, data=mat)
beeing "mat" the 10x16 matrix (without NAs), I got 17 values, first
the intercept, 9 numerical values and "NA" for the last 7 genes. Does
anybody you know why this is happening or how I can model using the 16
genes?
You don't have enough observations to use all 16 predictors plus intercept, if you really only have 10 samples. The NA coefficients are the one that can't be estimated given your observations. You'll need to rethink how to analyse these data. G
I hope anyone could help me with this! Many thanks in advance, Paul [[alternative HTML version deleted]]
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