INLA_code.R is an R script file to analyze scaup pair abundance using a Gompertz state-space model containing a covariate for snow cover extent. This script assumes that the INLA package has been downloaded from http://www.r-inla.org. The data set (ss_model_inla.csv) should be in the working directory when running this code.
ss_model_inla.csv is a comma-separated text file containing the scaup dataset. Column definitions are:
y: counts from each stratum in each year from BPOP aerial survey
stratum: each stratum number, adjusted for analysis in INLA, where ‘1’ = Stratum 13 as defined by the BPOP survey, ‘2’ = Stratum 14, ‘3’ = Stratum 15, ‘4’ = Stratum 16, ‘5’ = Stratum 17, and ‘6’ = Stratum 18
year: year since beginning of survey (1955)
stand.snow: standardized covariate for snow cover extent
N: number of segments flown in each stratum each year