This project uses data gathered by the Michigan department of environmental quality and Virginia Tech. My personal goal with this project was to implement a new type of plot (violin) and to improve my labeling clarity.
This plot uses a logarithmic scale to keep the plot in a form that can be read at a glance:
scale_y_log10(
breaks = c(0.01, 1, 10, 100),
labels = c("0", "1", "10", "100")) +
Below is the full code for this plot:
library(tidyverse)
#import data
flint_mdeq <- readr::read_csv('https://raw.githubusercontent.com/rfordatascience/tidytuesday/main/data/2025/2025-11-04/flint_mdeq.csv')
flint_vt <- readr::read_csv('https://raw.githubusercontent.com/rfordatascience/tidytuesday/main/data/2025/2025-11-04/flint_vt.csv')
#clean mdeq data and combine
flint_mdeq <- filter(flint_mdeq, is.na(notes))
flint_mdeq <- select(flint_mdeq, -c(notes, lead2))
flint <- bind_rows(flint_mdeq |> mutate(source = "MDEQ"), flint_vt |> mutate(source = "VTECH"))
flint <- flint |> filter(lead > 0)
#find mean and median for both data sets
stats <- flint |>
group_by(source) |>
summarize(median_lead = median(lead),
mean_lead = mean(lead))
#create subtitle
subtitle <- paste(
"MDEQ Median: ", round(stats$median_lead[stats$source == "MDEQ"], 2),
"| MDEQ Mean: ", round(stats$mean_lead[stats$source == "MDEQ"], 2),
"\nVTECH Median: ", round(stats$median_lead[stats$source == "VTECH"], 2),
"| VTECH Mean: ", round(stats$mean_lead[stats$source == "VTECH"], 2)
)
#plot
ggplot(flint, aes(x = source, y = lead + 0.01)) +
geom_violin(trim = FALSE, alpha = 0.6) +
coord_flip() +
scale_y_log10(
breaks = c(0.01, 1, 10, 100),
labels = c("0", "1", "10", "100")) +
labs(
title = "Lead Concentration in Flint Michigan Samples",
subtitle = subtitle,
x = NULL,
y = "Lead Concentration (ppb, log scale)") +
theme_minimal()