Hierarchical Deep Reinforcement Learning for VWAP Strategy Optimization

Designing algorithmic trading strategies targeting volume-weighted average price (VWAP) for long-duration orders is a critical concern for brokers. Traditional rule-based strategies are explicitly predetermined, lacking effective adaptability to achieve lower transaction costs in dynamic markets. Numerous studies have attempted to minimize transaction costs through reinforcement learning. However, the improvement for long-duration order trading strategies, such as VWAP strategy, remains limited due to intraday liquidity pattern changes and sparse reward signals. To address this issue, we propose a jointed model called Macro-Meta-Micro Trader, which combines deep learning and hierarchical reinforcement learning. This model aims to optimize parent order allocation and child order execution in the VWAP strategy, thereby reducing transaction costs for long-duration orders. It effectively captures market patterns and executes orders across different temporal scales. Our experiments on stocks listed on the Shanghai Stock Exchange demonstrated that our approach outperforms optimal baselines in terms of VWAP slippage by saving up to 2.22 base points, verifying that further splitting tranches into several subgoals can effectively reduce transaction costs.