The decision tree in an interactive voice response (IVR) system is a sort of script that says what questions or prompts the system should say and what are accepted inputs from the user. The simpkest forms will use text to speach for the computer utterences and then use the phone number pad to choose between fixed alternatuves. More sophisticated systems may use speach recognition to allow a greater range of human inputs. IVR decsion trees are often built using graohical interfaces with flow lines between prompt-response blocks.
This is related to, but different from the use of decsion trees in machine learning
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Links:
gojs.net: Example IVR decsion tree at GoJS.- nngroup.com: The UX of Phone-Tree Systems: 16 Usability Guidelines