Comparing the data set

In addition to simple mathematical operators like subtraction and division, you can ask R to make comparisons: greater than with >, less than with <, and equality with ==.

For example, we can ask if boys outnumber girls in each year with the expression present$boys > present$girls (Try it by typing it into the console). This command returns 63 values of either TRUE if that year had more boys than girls, or FALSE if that year did not.

This output shows a different kind of data than we have considered so far. In the present data frame our values are numerical (the year, the number of boys and girls). Here, we've asked R to create logical data, data where the values are either TRUE or FALSE. This is called a boolean value. In general, data analysis will involve many different kinds of data types, and one reason for using R is that it is able to represent and compute with many of them.

Try the expression present$boys > present$girls.
Inspect the result.

Exercise

Comparing the data set

Instructions