Dear Statalisters,
I'm investigating the relationship between the number of bats recorded
along a series of transects and the landscape characteristics of the
transects. I intend to model the count data using xtpoisson, then convert
the dependent variable to presence/absence and model using xtlogit.
However, my transects vary in length, which will affect both the number of
bats encountered and to a lesser extent bat presence/absence. I intend to
include transect length as an offset when using xtpoisson, but should I
also include it as an offset when using xtlogit? Does an offset work in
comparable way with binary data?
Many thanks,
Katherine Boughey
--
Centre for Ecology, Evolution and Conservation
School of Environmental Sciences
University of East Anglia
Norwich
NR4 7TJ
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