Exercises: 05-27-20

Packages

library(tidyverse)

Data

Flint water

flint <- read_csv("http://www2.stat.duke.edu/~sms185/data/health/flint.csv")

Each row represents a home in Flint, Michigan. Water lead contaminant value were recorded at three times as represented by draw1, draw2, and draw3.

Exercise 1

Problem

Create a visualization of the data from object flint. Utilize one of the below packages.

library(ggcorrplot) # correlogram plots
library(ggpol)      # parliment plots and more
library(patchwork)  # combining plots
library(gganimate)  # animations
library(ggiraph)    # interactive plots

Solution

# reshape the data
flint_long <- flint %>% 
  pivot_longer(cols = draw1:draw3, names_to = "draw", values_to = "pb_level")

# create a time plot
p1 <- flint_long %>% 
  filter(zip == 48507, pb_level < 75) %>% 
  ggplot(mapping = aes(x = draw, y = pb_level, group = id)) +
  geom_point() +
  geom_line(color = "grey60") +
  scale_x_discrete(labels = c("Draw 1", "Draw 2", "Draw 3")) +
  labs(y = "Lead level (ppb)", x = "") +
  theme_minimal(base_size = 16)

# create a boxplot
p2 <- flint_long %>% 
  filter(zip == 48507, pb_level < 75) %>% 
  ggplot(mapping = aes(x = draw, y = pb_level)) +
  geom_boxplot() +
  scale_x_discrete(labels = c("Draw 1", "Draw 2", "Draw 3")) +
  labs(y = "", x = "") +
  theme_minimal(base_size = 16)

# create a density plot
p3 <- flint_long %>% 
  filter(zip == 48507, pb_level < 75) %>% 
  ggplot(mapping = aes(x = pb_level, fill = draw)) +
  geom_density(alpha = .3) +
  theme_minimal(base_size = 16) +
  labs(x = "Lead level (ppb)", y = "Density", fill = "Draw time (seconds)") +
  scale_fill_discrete(labels = c("0", "45", "120")) +
  theme(legend.position = "bottom") 

# patchwork to bring everything together
(p1 + p2) / p3