Displaying 1 result from an estimated 1 matches for "loetempmod".
2013 Jan 12
4
nesting in CoxPH with survival package
...ed twice in different experimental
periods (e.g. Temp5 performed in Period A and C, Temp4 performed in
Period B and D)
I am trying to see if survival time is affected by the treatment
temperature. To do this I am using temperature and experimental
period nested within temperature as factors.
> LOEtempmod.5days=coxph(LOE.stable.5days~Temp+Temp/Period,data=goodstable)
Warning message:
In coxph(LOE.stable.5days ~ Temp + Temp/Period, :
X matrix deemed to be singular; variable 2 5 6 7
1. Is this an appropriate way of nesting?
2. Can this error message be ignored?
Any help would be much appreciated,...