Learn in the textbookData Science and Modeling & Simulation
DefinitionA decision tree (デシジョンツリー, also called 決定木) is a method that shows how decisions and outcomes split, in the form of a branching diagram.
ExplanationFollow the conditions or options at each fork and the conclusion appears at a leaf, the end of the branch. Put probabilities on the branches and you can compare options by expected value, the sum of each result multiplied by its probability. Machine learning also uses this method to classify data step by step.
AnalogyIt works like following signposts: you read one at every fork, and where you end up is your answer.
Memory hookThe name is just "decision" plus "tree", and calling the endpoints "leaves" extends the same image.