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Title: Pick the Moment: Identifying Crucial Pedagogical Decisions Using Long-Short Term Rewards.
Abstract: Identifying critical decisions is one of the most challenging decision-making problems in real-world applications. In this work, we propose a novel Reinforcement Learning (RL) based Long-Short Term Rewards (LSTR) framework for critical decisions identification. RL is a machine learning area concerned with inducing effective decision-making policies, following which result in the maximum cumulative "reward." Many RL algorithms find the optimal policy via estimating the optimal Q-values, which specify the maximum cumulative reward the agent can receive. In our LSTR framework, the "long term" rewards are defined as "Q-values" and the "short term" rewards are determined by the "reward function." Experiments on a synthetic GridWorld game and real-world Intelligent Tutoring System datasets show that the proposed LSTR framework indeed identifies the critical decisions in the sequences. Furthermore, our results show that carrying out the critical decisions alone is as effective as a fully-executed policy.
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In Proceedings of the 13th International Conference on Educational Data Mining (EDM)
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National Science Foundation
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