In this section, we will explore the
MovieLense dataset. For this purpose, we will use
recommenderlab to build recommender systems and
ggplot2 to visualize their results. Let's load the packages and the data:
library("recommenderlab") library("ggplot2") data(MovieLense) class(MovieLense) ##  "realRatingMatrix" ## attr(,"package") ##  "recommenderlab"
MovieLense is a
realRatingMatrix object containing a dataset about movie ratings. Each row corresponds to a user, each column to a movie, and each value to a rating.
Exploring the nature of the data
Let's take a quick look at
MovieLense. As explained in the previous section, there are some generic methods that can be applied to
realRatingMatrix objects. We can extract their size ...