Hello:
I would like to run a Cox proportional hazards regression on crayfish
dislodgement at different water velocities by crayfish size class and
substrate (rock) type. Additionally, there is a covariate variable, rock
movement that may be influencing crayfish dislodgment. So...
I have crayfish size class (CFSZCL) and substrate type (SUBSZ) as fixed
factors influencing the dislodgment of crayfish at different water
velocities (SLIPVEL). Thus, I am currently using the call:
coxph(Surv(SLIPVEL, FREEDOM) ~ CFSZCL + SUBSZ + CFSZCL:SUBSZ, data =
data.table)
However, I would like to add rock movement (BEDLOAD) as a random
co-variate, which is not possible with the coxph() function. Is it
possible to do so with coxme() in the kinship package? If so, what is
the proper syntax?
Thanks for any help.
Justin Montemarano
