Procedure for separating time from a survival analysis

Piyumi — Wed, 15 Oct 2014 15:25:37 GMT

I need to find the effect of treatments on mortality rate of insects. My dependent variable is mortality rate and my independent variable is treatments. Each treatment was replicated 4 times. The exposure times of the treatments are different, but, within a treatment, the exposure times are the same. When I conducted one-way ANOVA without considering the time effect, I see treatments have a significant effect on the survival. However, the exposure time also affect the dependent variable mortality. I tried separating the effect of time using multiple logistic regression and ANOVA. However, I think the program identifies time and treatment both as a single variable. Please see the attached data sheet. Any advise on this would be much appreciated.

Death rate	Treatment	Time (days)
0.3	R2	8
0.1	R2	8
0.1	R2	8
0.4	R2	8
0.7	R4	16
0.7	R4	16
0.7	R4	16
0.7	R4	16
0.9	R6	24
0.8	R6	24
0.8	R6	24
0.9	R6	24

Re: Procedure for separating time from a survival analysis

PGStats — Wed, 15 Oct 2014 17:07:10 GMT

Treatment and time are perfectly confounded in your experimental design. There is no way you can tell them apart. - PG

topic Procedure for separating time from a survival analysis in Statistical Procedures

Procedure for separating time from a survival analysis

Re: Procedure for separating time from a survival analysis