Lab 3.2 - Visualization Composition

library(tidyverse)
library(scales)
library(gapminder)

This document presents some modifications on the health-and-wealth plot.

Rebuilding the Health-and-Wealth Plot

Here is the code for the plot shown in class on Wednesday:

gapminder %>% 
  filter(year == 2007) %>% 
  ggplot() +
  aes(x = gdpPercap, y = lifeExp) +
  geom_point(alpha = .8) + 
  aes(color = continent) +
  aes(size = pop) + 
  scale_x_continuous(
    breaks = c(400, 4000, 40000),
    trans = "log10") +
  labs(x = "GDP per Capita") +
  labs(y = "Life Expectancy (years)") +
  labs(color = "Continent") +
  labs(size = "Population") +
  scale_size_area(labels = label_comma()) +
  theme_bw() + 
  annotation_logticks(sides = "b")

🚧 Type or copy this code into the following code chunk one line at a time, running the code for each new line to see what it does. We’ve started the process for you.

# Start with the dataset from the GapMinder package.
gapminder %>% 
  # Include only the records where ...
  filter(year == 2007)

## # A tibble: 142 × 6
##    country     continent  year lifeExp       pop gdpPercap
##    <fct>       <fct>     <int>   <dbl>     <int>     <dbl>
##  1 Afghanistan Asia       2007    43.8  31889923      975.
##  2 Albania     Europe     2007    76.4   3600523     5937.
##  3 Algeria     Africa     2007    72.3  33333216     6223.
##  4 Angola      Africa     2007    42.7  12420476     4797.
##  5 Argentina   Americas   2007    75.3  40301927    12779.
##  6 Australia   Oceania    2007    81.2  20434176    34435.
##  7 Austria     Europe     2007    79.8   8199783    36126.
##  8 Bahrain     Asia       2007    75.6    708573    29796.
##  9 Bangladesh  Asia       2007    64.1 150448339     1391.
## 10 Belgium     Europe     2007    79.4  10392226    33693.
## # … with 132 more rows

Notes:

• You can run the code chuck and see the output in the RStudio editor pane by pressing the green arrow (on the upper right of the chunk).

• Write a comment about what that line does using the # comment notation. The first 1.5 comments are written for you (e.g., # Include only the records where...).

• Omit the %>% (the pipe operator) or + at the end of a line until you’re ready to enter the next line (e.g., you’ll need to add %>% to the end of the filter line to go on).

• Practice using tab completion and the keyboard shortcut Ctrl-Shift-M to enter the %>%.

• Look up the Help for a few of the functions by clicking on the function name and then pressing the F1 key.

• Run the chunk. Observe what changed from what was there before.

Modifying the Health-and-Wealth Plot

Here is a modified version of the previous plot.

🚧 Duplicate your code chunk here, change its name (e.g., {r more-health-and-wealth}), and try these extensions:

• Change the year to your birth year or another interesting year in history. Note: here are the available years:

unique(gapminder$year)

##  [1] 1952 1957 1962 1967 1972 1977 1982 1987 1992 1997 2002 2007

• Try combining the aes lines together into a single aes command (with commas between the parts). Then try the same for the labs.

• Use commas in the x axis labels. (Find the part that adds commas to the scale for area. Use the same labels code in the part that already customizes other aspects of the scale for x.)

• Modify the scaling range of the y axis by adding this line coord_cartesian(ylim = c(40, 90)) + and setting the y limits to something you consider appropriate.

• Try some other themes. (at least try theme_gray, theme_classic, and theme_minimal).

Be prepared to submit your final RMarkdown file.