GLM HELP NEEDED!
On 01/02/2017 8:28 AM, CHIRIBOGA Xavier wrote:
Dear colleagues, I am trying to perform a GLM. I tried again without using attach()...but still is not working. Do you have any idea to help me? Thank you again, Xavier a <- read.table(file.choose(), h<-T)
The "h<-T" argument doesn't make sense. You are just lucky that it worked here. For arguments you almost always use "=". It's also a bad idea to use "T" as an abbreviation for "TRUE", but that won't always cause problems.
head(a)
time treatment transinduc 1 1 CHA0+Db 1,0768 2 1 CHA0+Db 1,0706 3 1 CHA0+Db 1,0752 4 1 CHA0+Db 1,0689 5 1 CHA0+Db 1,1829 6 1 PCL+Db 1,1423
I assume that transinduc is supposed to be real numbers, with comma as the decimal separator. You need to use dec = "," in read.table to read that properly.
summary(a)
time treatment transinduc
Min. :1.000 CHA0 :10 1,0488 : 6
1st Qu.:1.000 CHA0+Db: 9 1,0724 : 4
Median :1.000 Db : 9 1,0752 : 3
Mean :1.433 HEALTHY:15 1,0954 : 3
3rd Qu.:2.000 PCL :10 1,0001 : 2
Max. :2.000 PCL+Db :14 1,0005 : 2
(Other):47
m1<-glm(a$transinduc~a$time*a$treatment,data=a,family="poisson")
Error in if (any(y < 0)) stop("negative values not allowed for the 'Poisson' family") :
valor ausente donde TRUE/FALSE es necesario
Adem?s: Warning message:
In Ops.factor(y, 0) : '<' not meaningful for factors
It doesn't make sense to use fractional values like 1.0488 in Poisson regression. Duncan Murdoch