The data below are part of a larger dataset of water velocities that caused urchins to become detached from kelp fronds. You can see that two “types” of measurement were taken for each urchin: maximum velocity (max) and sustained velocity (pe). These measurements were done randomly (with respect to order of urchin and type).
We think we should just add urchin as a random factor. Does the below mixed model seem right for dealing with these repeated measures?
library(lme4) mod <- lmer(vel_ms ~ diameter_mm * type + (1 | urchin), data)
Thanks for any feedback!
Josh (and David Connolly)