# Bar Plots

A bar plot creates a bar for each level of a factor variable. An easy way to think about this is if you had a question with four possible answers, A, B, C, and D. A bar plot of the data would have a bar labeled A, and the height of the bar would be the number of times someone had answered A. Then there would be a bar labeled B, whose height was the number of times people had answered B. Etcetera.

Lets look at a concrete example. If you use the `plot()`

function on categorical data,

plot(labike$type)

you will get a bar plot that looks like this:

Each bar represents how many times each of those categories appeared in the data set. So, `bike lane`

appeared 5 times (there were five rows in the `labike.csv`

dataset that said `bike lane`

), `bike path`

and `bike route`

each appeared a little more than 5 times, and `none`

appeared 20 times. This lets you see the distribution of responses.

Another way you could have made a barplot is using the `barplot()`

function:

barplot(table(cdc$gender))

This plot shows us that both `Male`

and `Female`

appeared about 7000 times. Since these data came from a random survey, we would expect to see a 50/50 split between genders, so this makes sense.