# Value Labels

To understand value labels in R, you need to understand the data structure factor.

You can use the factor function to create your own value labels.

```
# variable v1 is coded 1, 2 or 3
# we want to attach value labels 1=red, 2=blue, 3=green
mydata$v1 <- factor(mydata$v1,
levels = c(1,2,3),
labels = c("red", "blue", "green"))
```

```
# variable y is coded 1, 3 or 5
# we want to attach value labels 1=Low, 3=Medium, 5=High
mydata$v1 <- ordered(mydata$y,
levels = c(1,3, 5),
labels = c("Low", "Medium", "High"))
```

Use the **factor()** function for **nominal data** and the **ordered()** function for **ordinal data**. R statistical and graphic functions will then treat the data appriopriately.

Note: factor and ordered are used the same way, with the same arguments. The former creates factors and the later creates ordered factors.

## To Practice

Factors are covered in the fourth chapter of this free interactive introduction to R course.