I am trying to plot the geographical distribution of wheat production using a county-level data set.
In order to create the data set, I combined a data set of county-level fips code with unique latitude-longitude for each fips code, with a data set of county-level wheat production.
I do not know why, it shows gaps between States, instead of having them connected (figure below)
library(maps) g43 <- wheat_corn_insurance1 %>% filter(year==1989) %>% filter(wheat==1)%>% ggplot(aes(x = longitude, y = latitude, group = state, fill = stateproduction/1000)) + geom_polygon(color = NA) + scale_fill_gradient(low = "white", high = "red") + labs(title = "County-Level Choropleth Map", subtitle = "Wheat Production (thousand bu), 1989") g43
I tried using the urbnmapr package as well, but I received a similar result.
Can someone help me with this?