Regression Analysis with R

Regression trees

Decision trees are used to predict a response or class y from several input variables x₁, x₂,…,x_n. If y is a continuous response, it's called a regression tree, if y is categorical, it's called a classification tree. That's why these methods are often called Classification and Regression Tree (CART). The algorithm is based on the following procedure: at each node of the tree, we check the value of one the input x_i and depending of the (binary) answer we continue to the left or to the right branch. When we reach a leaf we will find the prediction.

This algorithm starts from grouped data into a single node (root node) and executes a comprehensive recursion of all possible subdivisions at every step. At each step, the best subdivision ...