3.2 Additional R Packages

If a package that you want to use is not in the list on your computer, this means it is not stored on your computer and must be downloaded. You use the Install tab under the Packages tab to do this.

Try installing the psych package. Click on the Install tab and be sure that the box for Install dependencies is checked. Checking this box helps ensure that if a function in the psych package depends on another function in another package, then that package is also installed. Note the installation of the psych package adds to your list of available packages.

Be aware that now the psych package is available in your computer storage, but the package is not currently loaded for use. If you tried to use a function in the package, but the package is not loaded, R will let you know that something is amiss. How do you correct this? By using the library(psych) command to load the library into your workspace.

Finally, packages are modified over time. It is good practice to check whether updates are needed. This is done by clicking on the Update tab (right next to the Install tab).