Decision trees are part of the foundation for Machine Learning. Although they are quite simple, they are very flexible and pop up in a very wide variety of situations. This StatQuest covers all the basics and shows you how to create a new tree from scratch, one step at a time. NOTE: This is an updated and revised version of the Decision Tree StatQuest that I made back in 2018. It is my hope that this new version does a better job answering some of the most frequently asked questions people asked about the old one. Note, you may also want to learn about... Regression Trees: https://www.youtube.com/watch?v=g9c66TUylZ4 Bias and Variance (and over fitting): https://www.youtube.com/watch?v=EuBBz3bI-aA Cross Validation: https://www.youtube.com/watch?v=fSytzGwwBVw Pruning Trees: https://www.youtube.com/watch?v=D0efHEJsfHo For a complete index of all the StatQuest videos, check out: https://statquest.org/video-index/ If you'd like to support StatQuest, please consider... Buying my book, The StatQuest Illustrated Guide to Machine Learning: PDF - https://statquest.gumroad.com/l/wvtmc Paperback - https://www.amazon.com/dp/B09ZCKR4H6 Kindle eBook - https://www.amazon.com/dp/B09ZG79HXC Patreon: https://www.patreon.com/statquest ...or... YouTube Membership: null ...a cool StatQuest t-shirt or sweatshirt: null ...buying one or two of my songs (or go large and get a whole album!) https://joshuastarmer.bandcamp.com/ ...or just donating to StatQuest! https://www.paypal.me/statquest Lastly, if you want to keep up with me as I research and create new StatQuests, follow me on twitter: https://twitter.com/joshuastarmer 0:00 Awesome song and introduction 0:18 Basic decision tree concepts 3:16 Building a tree with Gini Impurity 9:15 Numeric and continuous variables 12:35 Adding branches 13:56 Adding leaves 14:32 Defining output values 15:12 Using the tree 15:38 How to prevent overfitting #StatQuest #decisiontree #ML