knitr::opts_chunk$set(echo = T,
                      warning = F,
                      message = F,
                      fig.align = "center",
                      fig.height = 8,
                      fig.width = 8)

## Load the required package: tidyverse
library(tidyverse)

## Read in the coasters.csv file as coasters
coasters <- read.csv('coasters.csv')

Data Description

The coasters data set has the information on 766 roller coasters. There are twelve variables (columns), and the relevant ones are:

  1. name: Name of the roller coaster
  2. type: The type of roller coaster (wood/steel/other)
  3. lift: The way the coaster is lifted up the first hill (chain/launch/other)
  4. length_ft & height_ft: The length and height of the roller coaster, in feet
  5. speed_mph: The max speed of the coaster, in miles per hour

Question 1: Basic GGPlot Scatterplot

Create a scatterplot of the speed_mph by height_ft with the points colored by length_ft, shaped by lift, and partially transparent. See what the graph should look like in Brightspace.

Save the graph as gg_q1 and display the graph in the knitted document.

gg_q1 <- 
  ggplot(
    data = coasters,
    mapping = aes(
      x = height_ft,
      y = speed_mph
    )
  ) +
  geom_point(
    mapping = aes(
      color = length_ft,
      shape = lift
    ),
    alpha = 0.75
  ) 
  
gg_q1

Does something seem wrong with the data? Describe what stands out as likely incorrect

Question 2: Theme and Text

Create the graph seen in question 2 in Brightspace. Save the graph as gg_q2 and display it in the knitted document.

gg_q2 <- 
  gg_q1 +
  # Adding the title, caption, and changing the label
  labs(
    title = "Roller Coasters: Speed, Height, and Length",
    x = "Height",
    y = "Speed",
    color = 'Length',
    shape = 'Lift Type',
    caption = 'Data: rcdb.com'
  ) +
  # Changing the theme
  theme_test() + 
  # Custom theme changes
  theme(
    # Centering the title
    plot.title = element_text(hjust = 0.5, size = 16),
    # Moving the legend to the bottom
    legend.position = 'bottom'
  ) + 
  # Leave this at the bottom to get the gradient bar to match 
  guides(color = guide_colorbar(barwidth = 15, barheight = 1))


gg_q2

Question 3: Changing axis and colors

Using the graph created in question 2, create the graph seen in Brightspace for question three. Make sure to pay close attention to the labels used for all 4 aesthetics!

Hint: You can use the help menu for the approbriate function to find how to get the colors to match!

Save the graph as gg_q3 and make sure to display it in the knitted document!

gg_q3 <- 
  gg_q2 + 
  # Adding units to the axes
  scale_x_continuous(
    breaks = 0:9*50,
    labels = paste0(0:9*50, 'ft')
  ) + 
  scale_y_continuous(
    breaks = 0:6*25,
    labels = paste0(0:6*25, 'mph')
  ) +
  # Changing the color and labels
  scale_color_continuous(
    type = 'viridis',
    breaks = (1:4)*2000,
    labels = c('2000ft','4000ft', '6000ft', '8000ft')
  ) +
  # Capitalizing Chain, Launch, and Other for lift
  scale_shape_manual(
    values = c('chain' = 'circle',
               'launch' = 'triangle',
               'other' = 'asterisk'),
    labels = c('chain' = 'Chain', 
               'launch' = 'Launch',
               'other' = 'Other')
    
  )


gg_q3

Question 4: Small Multiples

Using gg_q3, create three small multiples, one for Wood, one for Steel, and one for Other.

Since this is the final question, you don’t need to save the graph

gg_q3 +
  facet_wrap(
    facets = vars(type),
    ncol = 1
  )

Which type of coaster is the most common?

Which type of coaster is the rarest?