R for Social Scientists: Glossary

Use RStudio to write and run R programs.

Use install.packages() to install packages (libraries).

Access individual values by location using [].

Access arbitrary sets of data using [c(...)].

Use logical operations and logical vectors to access subsets of data.

Use read_csv to read tabular data in R.

Use factors to represent categorical data in R.

Use the dplyr package to manipulate dataframes.

Use select() to choose variables from a dataframe.

Use filter() to choose data based on values.

Use group_by() and summarize() to work with subsets of data.

Use mutate() to create new variables.

Use the tidyr package to change the layout of dataframes.

Use pivot_wider() to go from long to wide format.

Use pivot_longer() to go from wide to long format.

ggplot2 is a flexible and useful tool for creating plots in R.

The data set and coordinate system can be defined using the ggplot function.

Additional layers, including geoms, are added using the + operator.

Boxplots are useful for visualizing the distribution of a continuous variable.

Barplots are useful for visualizing categorical data.

Faceting allows you to generate multiple plots based on a categorical variable.

JSON is a popular data format for transferring data used by a great many Web based APIs

The complex structure of a JSON document means that it cannot easily be ‘flattened’ into tabular data

We can use R code to extract values of interest and place them in a csv file