This function is deprecated as of choroplethr version 2.0.0. Please use ?state_choropleth, ?county_choropleth, ?zip_map and ?country_choroplethr instead. The last version of choroplethr in which this function worked was version 1.7.0, which can be downloaded from CRAN here: http://cran.r-project.org/web/packages/choroplethr/index.html
choroplethr(...)
All arguments are ignored.