R Programming Fundamentals

Examining and Changing the Levels of Pre-existing Factor Variables

Herein, we will create factor variables in a dataset both one at a time and by using a method that converts multiple variables at once. In order to do so, the following steps have to be executed:

1. Load the dplyr library. Use levels() to see how many levels of band_instruments$plays exist, as follows:

levels(band_instruments$plays)

2. Create a new variable, plays2, using ifelse() to change the levels bass and guitar to 1 and 2 using the following code:

band_instruments$plays2 <- ifelse(band_instruments$plays == "bass", 1,ifelse(band_instruments$plays == "guitar", 2, band_instruments$plays))

3. Use levels() to see how many levels of midwest$state exist as follows:

levels(midwest$state) ...