Lesson 2: Lines, trees and forests: the classic models

Module 3 · Lesson 2 · About 45 minutes · Needs: Lesson 1 (splits, overfitting, cross-validation)

The situation

Priya has handed over 40 tickets her agents labelled by hand: refund, shipping, warranty or other. Lesson 1 trained a classifier on them without saying what was inside. Dev asks: "What does it actually do with a ticket?" Marta adds: "If it sorts a message wrongly, can you tell me why?"

This lesson opens the box, tracing one ticket, "I was charged twice for one order.", through a line, a curve, a tree, a forest and three older classifiers.