I am writing a report where I used a slightly modified version of MCTS (not parallelized). I thought It could be interesting if I could calculate its time complexity. I'd appreciate any help I could get.
Here's the rough idea of how it works:
Instead of tree search, I'm using graph search meaning I keep a list of visited nodes in order to avoid adding duplicate nodes.
So in the expansion phase, I add all child nodes of the current node that aren't present elsewhere in the tree.
For the remaining phases, it's essentially the same as the basic version of MCTS, with a default random policy in the simulation step.