library(ggplot2)
library(dplyr)

## Warning: package 'dplyr' was built under R version 3.4.4

## 
## Attaching package: 'dplyr'

## The following objects are masked from 'package:stats':
## 
##     filter, lag

## The following objects are masked from 'package:base':
## 
##     intersect, setdiff, setequal, union

data("USArrests")

state_name_to_abbrev <- data.frame(
  abbrev = state.abb,
  name = state.name
)

head(USArrests)

##            Murder Assault UrbanPop Rape
## Alabama      13.2     236       58 21.2
## Alaska       10.0     263       48 44.5
## Arizona       8.1     294       80 31.0
## Arkansas      8.8     190       50 19.5
## California    9.0     276       91 40.6
## Colorado      7.9     204       78 38.7

arrests <- USArrests %>% 
  tibble::rownames_to_column(var = "name") %>% 
  inner_join(state_name_to_abbrev) %>% 
  select(name, abbrev, everything()) %>% 
  mutate(name = tolower(name))

## Joining, by = "name"

## Warning: Column `name` joining character vector and factor, coercing into
## character vector

## Warning: package 'bindrcpp' was built under R version 3.4.4

states <- map_data("state")

states %>% 
  inner_join(arrests, by = c("region" = "name")) %>% 
  ggplot() + 
  geom_polygon(aes(x = long, y = lat, fill = Murder , group = group), color = "white") + 
  coord_fixed(1.3) +
  guides(fill=FALSE) +
  theme_void()# do this to leave off the color legend

GGally::ggpairs(select_if(arrests, is.numeric))