Fig. 2
From: Spatial analysis and characteristics of pig farming in Thailand
Spatial datasets used as predictor variables for modeling the pig distribution in Thailand. The variables (1Â km resolution) include; a Travel time to the capital city (Bangkok) (log10 of time) [44], b Travel time to the provincial capitals (log10 of time) [44], c rainfed croplands (proportion within a square kilometer) [43], d irrigated croplands (proportion within a square kilometer) [43], e elevation (log10 of meter) [42], and f human population density (log10 of number of human per a square kilometer) [39]