Creates a plot of trendlines of votes remaining vs difference between candidates

elections_2020.R

library(tidyverse)
dat <- read_csv("https://github.com/alex/nyt-2020-election-scraper/raw/master/battleground-state-changes.csv")

dat <- dat %>%
  group_by(state) %>%
  mutate(lead_first = first(leading_candidate_name),
         biden_trump = ifelse(leading_candidate_name != lead_first | leading_candidate_name == "Trump",
                                    -vote_differential, vote_differential)) %>%
  ungroup()

# a faceted plot, highlighting differences between the states
pl <- dat %>%
  ggplot(aes(x = votes_remaining, y = biden_trump, colour = leading_candidate_name)) +
  geom_hline(yintercept = 0L) +
  geom_vline(xintercept = 0L) +
  geom_smooth(aes(group = "all"), colour = "black", method = "lm", fullrange = TRUE) +
  geom_point() +
  scale_x_reverse() +
  ## coord_cartesian(xlim = c(NA, 0), ylim = range(dat$biden_trump)) +
  scale_colour_manual(values = c("Biden" = "#0015bc", "Trump" = "#ff0000")) +
  labs(title = "US Elections 2020",
       subtitle = paste("last updated on", lubridate::now()),
       caption = "Data courtesy NYT, scraped by https://github.com/alex/nyt-2020-election-scraper",
       x = "Estimate of remaining votes",
       y = "Biden votes" ~ - ~ "Trump votes",
       colour = "Candidate") +
  facet_wrap( ~ state)

ggsave("bidenvstrumplead.png", pl, width = 10, height = 7)

# a single plot with all states
pl <- dat %>%
  ggplot(aes(x = votes_remaining, y = biden_trump, colour = state)) +
  geom_hline(yintercept = 0L) +
  geom_vline(xintercept = 0L) +
  annotate("rect", xmin = -Inf, xmax = +Inf, ymin = 0, ymax = Inf, fill = "#0015bc", alpha = .3) + 
  annotate("text", x = 5e5, y = 3e5, label = "Biden win") + 
  annotate("rect", xmin = -Inf, xmax = +Inf, ymin = -Inf, ymax = 0, fill =  "#ff0000", alpha = .3) + 
  annotate("text", x = 5e5, y = -3e5, label = "Trump win") + 
  geom_smooth(method = "lm", fullrange = TRUE) +
  geom_point() +
  scale_x_reverse() +
  coord_cartesian(xlim = c(NA, 0)) +
  scale_colour_viridis_d() + 
  labs(title = "US Elections 2020",
       subtitle = paste("last updated on", lubridate::now()),
       caption = "Data courtesy NYT, scraped by https://github.com/alex/nyt-2020-election-scraper",
       x = "Estimate of remaining votes",
       y = "Biden votes" ~ - ~ "Trump votes",
       colour = "State") 

ggsave("bidenvstrump_allstates.png", pl, width = 10, height = 7)