We will switch databases, to a set of data on item attributes.

And we will work on another of the especially attractive and powerful features of R: the capacity to select and work with specific elements of a larger database: subsetting rows and columns by number or place, name, and condition.

Then we’ll use subsets of the item attribute data to further examine correlations between variables.

This will start to prepare us for linear regression.

And that will lead up to mixed-effects modeling.