Boxplots are a type of graph that simplifies data into five numbers. If you imagine that the numbers in our dataset were sorted from lowest to highest, then the five-number summary would include:
- minimum, or smallest number
- maximum, or biggest number
- median, or middle number
- first quartile, which is located halfway between the minimum and the median
- third quartile, which is located halfway between the median and the maximum
Coders use the gf_boxplot() function like they use the gf_scatterplot() function: with two variables, in the format y_var ~ x_var.
Run the code below to see what we mean.
<iframe data-type="datacamp" id="extra-7-1" height="350" src="https://uclatall.github.io/mtucker-coding-study/data-camp/dc-extra-7-1.html"></iframe>In the example above, when we put the number 1 in place of one of the variables, we were able to use the gf_boxplot() function to view just one variable at a time (like steps). This is similar to the histogram functions we saw earlier, because histograms also view only one variable at a time.
Now, create a scatterplot for steps using 1 in place of the x variable.
Now we're ready to see what the two functions look like on the same graph. We can combine functions using the pipe symbol: %>%.
Create a layered boxplot and scatterplot for our steps data. Notice that they are different representations of the same underlying data.