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