4.4 Decision Tree

Decision Tree

A decision tress is an AI entity which uses algorithms to make decisions base on its current surroundings, state and well-being. Decisions tree's work in like a leaf framework but to make it work the needs to be a question, answer and then the outcome. The way this works is there will be a parent node (question) and then child nodes (answers) and each child node must come up with all possible answers that the parent node is asking. Now in a real world situation, you can see below a image (13) that is a very simple example of a decision tree in action. Now in a Call of Duty game the AI would be asking itself:

Have I taken any damage? -> Yes -> find a place to hide until healthy -> Do I now have full health?   -> No -> continue hiding until healthy -> Do I now have full health?   -> Yes -> Return to the battle scene.

Questions/conditions are Nodes. Yes/No options represent Edges. End actions are Leafs of the tree. (13)

The decision tree is a very popular algorithm used in AI gaming, it collates with states machines or FSM's (4.1 State Machines) in a way that it asks itself by using the decision tree, Am I hurt? Do I need to evade? Do I have enough health to attack? or am in any danger? If not I can wander. Like Deszhic mentions in his quote, questions represent the parent nodes, yes and no reply's represent the child and also the answers and final outcome creates the final shape of the leaf.