Decision Tree – Improve Decision-Making Processes. A decision tree is a collection of hands-on exercises and case studies that teach you to make better decisions faster. It’s simple: Think of a tough decision you’re facing in your personal or professional life, read the chapter relevant to it and then complete the exercises and try out the techniques. The tool explores possible solutions for a given problem. The tree typically branches into two or more alternative paths based on the answer to each question. The paths can be summarised in the form of a contingency table. The table displays the number of times each action is taken for each possible outcome, which allows you to decide which solution leads to the best results. Once you have identified the facts that are relevant to your decision, you can follow the flowchart through to make your choice.