Tessa,
Would you please leave in the context --that is your early remarks and mine?
Most of us on the R-help list do no use nabble and it is really annoying to have to go there to see what was discussed. I suspect that a lot of readers just don't bother and nabble users lose a lot of possible help that way.
In any case, I think your problem is a typo in the document.
My first suggestion gives exactly the same results shown in the document you supplied. Run this :
conc = c(0, 10, 20, 30, 40, 50)
signal = c (4, 22, 44, 60, 82, NA)
lm.r <- lm( signal ~ conc)
summary(lm.r)
I hope this helps.
John Kane
Kingston ON Canada
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