Preferred prime minister polling, New Zealand

graphing.r

# In RStudio, Ctrl+A then Run

library(ggplot2)
library(dplyr)
library(svglite)

setwd("xxxxx") # replace with own working directory

# Read data
csvData <- read.csv("poll-data.csv")
pollingData <- arrange(csvData, desc(as.Date(Date, '%Y/%m/%d')))

# Plot data
spansize <- 0.45 # higher = smoother
ggplot(pollingData, aes(x = as.Date(Date, '%Y/%m/%d'))) +
  theme_bw() +
  
  # Ardern
  geom_point(aes(y = Ardern, colour = "Ardern"), size = 2, alpha = 0.3) +
  geom_smooth(aes(y = Ardern, colour = "Ardern"), span = spansize, se = FALSE) +
  # Collins
  geom_point(aes(y = Collins, colour = "Collins"), size = 2, alpha = 0.3) +
  geom_smooth(aes(y = Collins, colour = "Collins"), span = spansize, se = FALSE) +
  # Muller
  geom_point(aes(y = Muller, colour = "Muller"), size = 2, alpha = 0.3) +
  geom_smooth(aes(y = Muller, colour = "Muller"), span = spansize, se = FALSE) +
  # Bridges
  geom_point(aes(y = Bridges, colour = "Bridges"), size = 2, alpha = 0.3) +
  geom_smooth(aes(y = Bridges, colour = "Bridges"), span = spansize, se = FALSE) +
  # English
  geom_point(aes(y = English, colour = "English"), size = 2, alpha = 0.3) +
  geom_smooth(aes(y = English, colour = "English"), span = spansize, se = FALSE) +
  # Peters
  geom_point(aes(y = Peters, colour = "Peters"), size = 2, alpha = 0.3) +
  geom_smooth(aes(y = Peters, colour = "Peters"), span = spansize, se = FALSE) +
  # Seymour
  geom_point(aes(y = Seymour, colour = "Seymour"), size = 2, alpha = 0.3) +
  geom_smooth(aes(y = Seymour, colour = "Seymour"), span = spansize, se = FALSE) +
  
  # Y-axis
  scale_y_continuous(limits = c(0, 70), breaks = c(0,10,20,30,40,50,60,70), minor_breaks = waiver(), expand = c(0, 0)) +
  # X-axis
  scale_x_date(date_breaks = "4 months", date_labels = "%b '%y", minor_breaks = "1 month") +
  # Axis styling
  theme(
    plot.background = element_rect(fill = "white", color = NA),
    axis.text.x = element_text(angle = 0, vjust = 0.5, size = 10),
    axis.text.y = element_text(size = 12),
    axis.title.y = element_text(size = 12)
  ) +
  # Axis labels
  labs(y = "Support (%)", x = NULL) +
  # Colors and key
  scale_color_manual(
    name = "",
    # Legend
    labels = c(
      "Jacinda Ardern",
      "Judith Collins",
      "Todd Muller",
      "Simon Bridges",
      "Bill English",
      "Winston Peters",
      "David Seymour"
    ),
    # Color mapping
    values = c(
      # For color values see https://www.nceas.ucsb.edu/sites/default/files/2020-04/colorPaletteCheatsheet.pdf p.3
      "Ardern"="red",
      "Collins"="dodgerblue",
      "Muller"="darkslateblue",
      "Bridges"="blue",
      "English"="cyan",
      "Peters"="black",
      "Seymour"="gold"
    )
  ) +
  theme(
    legend.position = "bottom",
    legend.text = element_text(size = 12)
  )

# Save graph
ggsave(
  "polling-graph.svg",
  width = 12,
  height = 7
)

poll-data.csv