What classification does the Decision Tree make if a final node has 50% of the predicted outcome?

Course Q&A Machine Learning Specialization Advanced Learning Algorithms
1

In the lecture video Andrew says that because 1/3 of the set are cats, then the model will predict ‘Not Cat’.
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I am wondering what happens if the set had example 1 cat and 1 dog (and there were no more splits due to maximum depth, and/or information gain below a threshold, and/or number of examples below a threshold), what would it predict?

Thanks!

2

Hello @Daniel_Fourie,

It depends on the developer of the decision tree algorithm. If they determine the final class with y > .5, then the marginal case will end up as Not Cat. It is by choice.

Cheers,
Raymond