systematic_var_1 consists of simulated line transect data with large
differences in transect length. In systematic_var_2 that transect length
gradient is coupled with a strong animal gradient; exaggerating encounter
rate variance between transects.
Format
data.frame with 253 observations (systematic_var_1) or 256
observations (systematic_var_2) of 7 variables:
Region.Label stratum label (default)
Area stratum area (0.5 km^2)
Sample.Label transect identifier
Effort transect length (km)
object object ID
distance perpendicular distance (m)
Study.Area name of study area
Details
True population size is 1000 objects in the study area of size 0.5 km^2; such that true density is 2000 objects per km.
References
Fewster, R.M., S.T. Buckland, K.P. Burnham, D.L. Borchers, P.E. Jupp, J.L. Laake and L. Thomas. (2009) Estimating the encounter rate variance in distance sampling. Biometrics 65 (1): 225–236. doi:10.1111/j.1541-0420.2008.01018.x