# Theoretical maximum depth of a decision tree

During my machine learning labwork, I was trying to fit a decision tree to the IRIS dataset (150 samples, 4 features). The maximum theoretical depth my tree can reach which is, for my understanding, equals to (number of sample-1) when the tree overfits the training set. So, for my training set which consists of 100 samples that would be 99. However, I am unsure what would the maximum depth be if I want to impose that no less than 2 samples are contained in a leaf. Would it just be $${100 \over 2} - 1 = 49$$?

• Yes, your formula is correct. Nov 25 at 9:08
• Yes. And just want to add that if all of your features were categorical then max depth would have been 4. Nov 26 at 6:18