decision table

A decision table represents an input-output relationship as a table listing combinations of input variables and their corresponding outputs (sometimes a boolean yes/no value). An exhaustive list such as this is only useful for relatively simple decisions with a small nunber of variables and alternatives, but can be a lot clearer as replacement for or alongside more rule-based or algorithmic knowledge representations.

Here is a simple decision table to determine the kind of animal based on colour and size:

INPUT		OUPUT
colour	size	animal
grey	large	elephant
grey	small	mouse
blue	large	whale
blue	small	butterfly
pink	large	pink elephant
...	...	...