Print the mpg
dataset to your console.
► Solution:
mpg
## # A tibble: 234 x 11
## manufacturer model displ year cyl trans drv cty hwy fl cla…
## <chr> <chr> <dbl> <int> <int> <chr> <chr> <int> <int> <chr> <ch>
## 1 audi a4 1.8 1999 4 auto… f 18 29 p com…
## 2 audi a4 1.8 1999 4 manu… f 21 29 p com…
## 3 audi a4 2 2008 4 manu… f 20 31 p com…
## 4 audi a4 2 2008 4 auto… f 21 30 p com…
## 5 audi a4 2.8 1999 6 auto… f 16 26 p com…
## 6 audi a4 2.8 1999 6 manu… f 18 26 p com…
## 7 audi a4 3.1 2008 6 auto… f 18 27 p com…
## 8 audi a4 q… 1.8 1999 4 manu… 4 18 26 p com…
## 9 audi a4 q… 1.8 1999 4 auto… 4 16 25 p com…
## 10 audi a4 q… 2 2008 4 manu… 4 20 28 p com…
## # ... with 224 more rows
View mpg
in RStudio’s dataset pane (via View()
). Display all Audis sorted by year then cylinder. What is the maximum number of highway miles per gallon in this dataset?
View(___)
► Solution:
View(mpg)
Create a few scatterplots using the following template (here with hwy
versus displ
):
ggplot(data = mpg) +
geom_point(mapping = aes(x = displ, y = hwy))
Share particularly interesting or boring examples you might encounter. Did you find anything surprising?
► Solution:
ggplot(data = mpg) +
geom_point(mapping = aes(x = displ, y = hwy))
More examples:
ggplot(data = mpg) +
geom_point(mapping = aes(x = cyl, y = drv))
ggplot(data = mpg) +
geom_point(mapping = aes(x = year, y = cyl))
ggplot(data = mpg) +
geom_point(mapping = aes(x = displ, y = manufacturer))
ggplot(data = mpg) +
geom_point(mapping = aes(x = cty, y = hwy))
Can you plot highway fuel economy given as liters per 100 kilometers against engine displacement?
Hint: Use the formula 235 / hwy
to convert from miles per gallon.
ggplot(data = ___) +
geom_point(mapping = aes(x = displ, y = ___))
► Solution:
ggplot(data = mpg) +
geom_point(mapping = aes(x = displ, y = 235 / hwy))
How can you reduce overplotting? Use your favorite search engine to find out.
ggplot(data = ___) +
geom____(_____)
Find more examples in Section 3.2.4 of the “R for data science” book (http://r4ds.had.co.nz).
Copyright © 2018 Kirill Müller. Licensed under CC BY-NC 4.0.