To figure out the correct variable name for region, inspect
as.data.frame(model)
.
Usage
# S3 method for class 'SpatialPolygonsDataFrame'
fortify(model, data, ...)
# S3 method for class 'SpatialPolygons'
fortify(model, data, ...)
# S3 method for class 'Polygons'
fortify(model, data, ...)
# S3 method for class 'Polygon'
fortify(model, data, ...)
# S3 method for class 'SpatialLinesDataFrame'
fortify(model, data, ...)
# S3 method for class 'Lines'
fortify(model, data, ...)
# S3 method for class 'Line'
fortify(model, data, ...)