Grammar of graphics I

1. Using the mtcars data, create a scatterplot of the fuel efficiency as a function of weight.

library(tidyverse)

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mtcars |> 
  ggplot(aes(x = wt, y = mpg)) +
  geom_point()

2. Repeat the plot but only with vehicles having 4 or 6 cylinders.

mtcars |> 
  filter(cyl < 8) |> 
  ggplot(aes(x = wt, y = mpg)) +
  geom_point()

3. Repeat plot #1 but add a smooth line underneath the data points.

mtcars |> 
  ggplot(aes(x = wt, y = mpg)) +
  geom_smooth() +
  geom_point()

`geom_smooth()` using method = 'loess' and formula = 'y ~ x'

4. Make a boxplot of fuel efficiency for each cylinder size.

mtcars |> 
  mutate(cyl = as.factor(cyl)) |> 
  ggplot(aes(x = cyl, y = mpg)) +
  geom_boxplot()

5. Add ” cylinders” to the end of each value in the cylinder column of data and replot #4.

mtcars |> 
  mutate(cyl = paste0(cyl, " cylinders")) |> 
  ggplot(aes(x = cyl, y = mpg)) +
  geom_boxplot()

6. Replot #4 ordering the cylinders such that the median mpg increases from left to right.

mtcars |> 
  mutate(cyl = as.factor(cyl)) |> 
  ggplot(aes(x = fct_reorder(cyl, mpg), y = mpg)) +
  geom_boxplot()