PPT-Lecture 15: Decision Trees

Lecture 15 Decision Trees Outline Motivation Decision Trees Splitting criteria Stopping Conditions amp Pruning Text Reading Section 81 p 303314 2 Geometry of Data Recall l ogistic regression. T state 8712X action or input 8712U uncertainty or disturbance 8712W dynamics functions XUW8594X w w are independent RVs variation state dependent input space 8712U 8838U is set of allowed actions in state at time brPage 5br Policy action is function Battiti. , Mauro . Brunato. .. The LION Way: Machine Learning . plus.  Intelligent Optimization. .. LIONlab. , University of Trento, Italy, . Apr 2015. http://intelligent-optimization.org/LIONbook. trees (cont.). If we pick the adjacent nucleotide, what gene tree do we expect?. A. C. B. A-B coalescence. AB-C coalescence. Split 2. Split 1. If we pick a nucleotide from a distant part of the genome, what gene tree do we expect?. A . decision tree. is a graphical representation of every possible sequence of decision and random outcomes (states of nature) that can occur within a given decision making problem.. A decision tree is composed of a collection of nodes (represented by circles and squares) interconnected by branches (represented by lines).. Arko. Barman. With additions and modifications by Ch. . Eick. COSC 4335 Data Mining. Example of a Decision Tree. categorical. categorical. continuous. class. Refund. MarSt. TaxInc. YES. NO. NO. NO. Yes. Decision Tree. Advantages. Fast and easy to implement, Simple to understand. Modular, Re-usable. Can be learned .  . can be constructed dynamically from observations and actions in game, we will discuss this further in a future topic called ‘Learning’). Decision Trees. Gavin Brown. www.cs.man.ac.uk/~gbrown. Recap: threshold classifiers. height. weight. Q. Where is a good threshold?. 10 20 30 40 50 60. 1. 0. Also known as “decision stump”. From Decision . Training Set:. Play Tennis?. Weak. Rain Mild High Weak No. Rain Mild High Weak No. Decision Trees: Another Example. Training Set:. Play Tennis?. Sunny. Weak. Econ 404 – Jacob LaRiviere . –. Guest Lecture Brian Quistorff. May 10, 2017. Agenda. Review CART. Cross-Validation. How apply to heterogeneity. Problems. Causal Tree. Random Forests. Tree Benefits Intuition. Sibel Adali, . Sujoy Sikdar. , Lirong Xia. Multi-Issue Voting. { , } . X. . { , }. Wine (. ).  . Main dishes (. ).  . Goal: Cater to people’s preferences. issues. Dr. Halimah Alshehri. 1. Introduction to Trees. DEFINITION 1 . A . tree. is a connected undirected graph with no simple circuits.. Because . a tree cannot have a simple circuit. , . a tree cannot contain multiple edges or loops. Sultan Almuhammadi ICS 254: Graphs and Trees 1 Graph & Trees Chapters 10-11 Acknowledgement This is a modified version of Module#22 on Graph Theory by Michael Frank Sultan Almuhammadi ICS 254: Graphs and Trees AVL Trees 1 AVL Trees 6 3 8 4 v z AVL Trees 2 AVL Tree Definition Adelson- Velsky and Landis binary search tree balanced each internal node v the heights of the children of v can differ by at most 1 Decision Trees and Decision Tables 2 Decision Trees and Decision Tables Often our problem solutions require decisions to be made according to two or more conditions or combinations of conditions Decision trees represent such decision as a