Inherently Interpretable Q-Learning

Summary

Reinforcement Learning algorithms, especially those that utilize Deep Neural Networks (DNN), have achieved significant and many times impressive results at solving problems within a broad range of applications. Since most implementations and model architectures are based on Neural Networks (NNs), which are non-interpretable by design, there is a growing desire for Interpretable Reinforcement Learning methods development, towards improving the algorithm’s decisions tracking and increase trust to AI systems, as well as  cooperation between intelligent agents and human users. A promising approach towards interpretable methods includes utilizing inherently interpretable methods such as Decision Trees. This thesis investigates interpretability in Reinforcement Learning by introducing the Stochastic Gradient Trees algorithm as the baseline for developing intelligent agents. To that end, we propose methods that utilize Stochastic Gradient Trees to perform Q-Learning and learn effective policies on several virtual environments. Moreover, a comparison of the interpretable and their counter non-interpretable methods is made under similar settings to study comparatively their efficacy in problem solving. Additionally, as a first step to human-AI collaboration using the inherently interpretable methods proposed in this thesis, experiments have been designed and performed in a collaborative game-setting, where transparency provision plays a significant role in improving collaboration in problem solving.