[Discussion] What do you do when a model isn't performing as you expect it to? • /r/MachineLearning

"Deterministic" means that if you give the model inputs the same X values you always get the same Y values. So most machine learning models are deterministic. But the models are usually also very hard to examine. A common mistake is to use variables which don't correlate with the output. Garbage in will alway lead to garbage out.