Chapter 4 Manage datasets

The previous chapter covered how to manage variables within a dataset. In this chapter, you will learn how to manage one or more datasets, including the following tasks:

• Select a subset of variables,
• Select a subset of observations,
• Exclude observations with missing data,
• Sort a dataset by values of one or more variables,
• Append (stacking) multiple datasets, and
• Merge (joining) multiple datasets.

We will use the same dataset as in the previous chapter.

load("Data/RheumArth-Chapter3.RData")
library(tidyverse)
mydat$Sex[mydat$Sex %in% c("f", "female")] <- "F"
mydat$Sex[mydat$Sex ==  "m"              ] <- "M"
mydat_tibble <- as_tibble(mydat)