Visualization 4: Spine Graph showing Percent of Prison Population By Race, 1940-2010

Prison Spine Graph

#Morgan Waterman
#US History Through Census Data
#Spine Graph for African American Prison Populations  

library(dplyr)
library(readr)
library(ggplot2)
library(RColorBrewer)
library(scales)

#Program to print plots
printplot <- function(plot, filename) {
  png(paste(filename,'.png', sep=''), height= 500, width = 1000)
  print(plot)
  dev.off()
}

#Read in data extract
ipums <- read_csv('data/FinalProjectDataNewest.csv', col_types = cols(PERWT=col_double()))

#Filter for age and exclude Alaska and Hawaii
a <- ipums %>% filter(AGE>=15 & AGE<=70)
aa<- a %>% filter(!(STATEFIP %in% c(2, 15)) | YEAR >=1960)

#recode RACE
b <- aa %>% mutate(Race = factor(ifelse(RACE %in% c(2), 1, 2),
      labels = c('Black', 'Other')))
      
#recode GQTYPE--create Institution
c <- b %>% mutate(Institution = factor(ifelse(GQTYPE==1, 1,
                                       ifelse(GQTYPE==2, 2, 3)),
                              labels = c('Institution', 'Prison prior to 1990', 'Other Group Quarters')))

#filter out Other Group Quarters and females
prisontotal <- c %>% filter(Institution!=3 & SEX==1)

#data frame just blacks
prisonblack <- prisontotal %>% filter(Race==2) %>% select(YEAR, Race) %>% rename(Brace=Race)

prisonpop <- left_join(prisontotal, prisonblack) %>% group_by(YEAR, Race) %>% summarise(Number=sum(PERWT))

#make total for yr
prisonyr <- prisonpop %>% group_by(YEAR) %>% mutate(totalprison=sum(Number))

prisonjoin <- left_join(prisonpop, prisonyr)

prisonpct <- prisonjoin %>% mutate(Percent = Number/totalprison)

#Prison spine graph
graphprison <- ggplot(prisonpct, aes(x= YEAR, y=Percent, fill=Race)) +
  geom_bar(stat='identity') +
  labs(fill = 'Race of Prisoners', title = 'Percent of Prisoners Who Are African American, 1940-2010', x = 'Year', y= 'Percent of Prisoners') +
  theme_bw(base_size=8) + 
  scale_x_continuous(breaks=c(1940, 1950, 1960, 1970, 1980, 1990, 2000, 2010))
  scale_y_continuous(labels=scales::percent)
printplot(graphprison, 'prisonrace')