US Census 2010 App

Coursera Data Science Specialization Department School of Public Health John Hopkins University

This Shiny app was built from the dataset counties.rds that contains demographic data for each county in the United States. It was collected using the UScensus2010 R package. This choropleth map application uses colors to display the regional variations of residents in counties across the United States who are white, black, hispanic or asian.

The dataset is in counties.rds and it contains:

• the name of each county in the United States
• the total population of the county
• the percent of residents in the county who are white, black, hispanic or asisn

A view of the demographic data for each county in the United States is shown below:

# loading the dataset using `readRDS`
counties <- readRDS("data/counties.rds")
head(counties)

             name total.pop white black hispanic asian
1 alabama,autauga     54571  77.2  19.3      2.4   0.9
2 alabama,baldwin    182265  83.5  10.9      4.4   0.7
3 alabama,barbour     27457  46.8  47.8      5.1   0.4
4    alabama,bibb     22915  75.0  22.9      1.8   0.1
5  alabama,blount     57322  88.9   2.5      8.1   0.2
6 alabama,bullock     10914  21.9  71.0      7.1   0.2

This sophisticated map application was created using the shiny package. A slider widget was added that allows you to interact with the choropleth map. This widget was added to the sidebarPanel in the ui.R script below, using min = 5, max = 100, value = c(5, 100) as the Range of Interest.

ui.R

shinyUI(fluidPage(
        titlePanel("USA Census App"),
        sidebarLayout(
                sidebarPanel(
                        h2("Overview"),
                        helpText("This shiny app creates demographic maps of the 2010 US Census."),
                        code('US Census Dataset:"counties.rds"'),
                        br(),
                        br(),
                        selectInput("var", 
                                    label = "Choose a variable to display",
                                    choices = c("Percent White", "Percent Black",
                                                "Percent Hispanic", "Percent Asian"),
                                    selected = "Percent White"),
                        sliderInput("range", 
                                    label = "Range of interest:",
                                  min = 5, max = 100, value = c(5, 100)),
                        br(),
                        br(),
                        img(src = "bigorb.png", height = 72, width = 72),
                        em("User-interface was made possible by:"), 
                        span("RStudio", style = "color:blue")),
                     mainPanel(
                        h2("The US Census Features: "),
                        br(),
                        p("* The percent of residents in the county who are white, black, hispanic, or asian"),
                        p("* The name of each county in the United States"),
                        p("* The the total population of the county"),
                        plotOutput("map")))))

server.R The helpers.R script shown in the R chunk below, uses the maps and the mapproj packages in R to create the choropleth map in the shiny census-app application.

library(maps)
library(mapproj)
counties <- readRDS("data/counties.rds")
source("helpers.R")
shinyServer(
        function(input, output) {
        output$map <- renderPlot({
                data <- switch(input$var, 
                               "Percent White" = counties$white,
                               "Percent Black" = counties$black,
                               "Percent Hispanic" = counties$hispanic,
                               "Percent Asian" = counties$asian)
                color <- switch(input$var, 
                                "Percent White" = "darkgreen",
                                "Percent Black" = "blue",
                                "Percent Hispanic" = "purple",
                                "Percent Asian" = "red")
                legend <- switch(input$var, 
                                 "Percent White" = "% White",
                                 "Percent Black" = "% Black",
                                 "Percent Hispanic" = "% Hispanic",
                                 "Percent Asian" = "% Asian")
                percent_map(var = data, 
                            color = color, 
                            legend.title = legend, 
                            max = input$range[2], 
                            min = input$range[1]
                            )})})