spsurvey: Spatial survey design and analysis (version 5.0)
spsurvey is an R package used for spatial probability survey design and analysis. Thespsurvey package implements the Generalized Random Tesselation Stratified (GRTS) algorithm to select spatially balanced probability samples via the grts() function. The grts() function flexibly accomodates other sampling design features, including stratification, varying inclusion probabilities, legacy (or historical) sites, minimum distances between sites, and two options for replacement sites. spsurvey also implements population paraemter estimation using a suite of analysis approaches, including categorical variable analysis (cat_analysis()), continuous variable analysis (cont_analysis()), relative risk analysis (relrisk_analysis()), attributable risk analysis (attrisk_analysis()), risk difference anlysis (diffrisk_analysis()), change analysis (change_analysis()), and trend analysis (trend_analysis()).