I encounter such an exercise question as below and have no clue so far.
Consider using decision trees/forests to implement Boolean functions, i.e. classifiers from {0,1}n to{0,1}.
1) Give a good upper bound for the VC-dimension of decision trees with l leaves.
2) What is a good upper bound for the VC-dimension of a random forest (thresholded linear combination of decision trees) with k trees where each tree has l leaves?
For question 1), I understand the VC-dimension of a decision tree with l Leaves is at least l, but I cannot come up with the upper bound.