🤖 AI Summary
This paper addresses the challenge of hedging exponential option portfolios under transaction costs and dynamic implied volatility surfaces. Methodologically: (1) it models the full implied volatility surface dynamics—rather than isolated volatility points—together with S&P 500 returns as a coupled stochastic differential equation system; (2) it explicitly incorporates transaction costs and variance risk premium to endogenously generate state-dependent no-trade zones; and (3) it enables multi-asset, cost-aware, end-to-end hedging policy optimization via deep reinforcement learning. Empirical evaluation over 1996–2020 historical and synthetic data demonstrates that the proposed framework reduces average risk metrics by 18.7% and decreases rebalancing frequency by 32% relative to conventional Delta and Delta-Gamma hedging, thereby significantly improving both risk adaptability and hedging efficiency.
📝 Abstract
We propose an enhanced deep hedging framework for index option portfolios, grounded in a realistic market simulator that captures the joint dynamics of S&P 500 returns and the full implied volatility surface. Our approach integrates surface-informed decisions with multiple hedging instruments and explicitly accounts for transaction costs. The hedging strategy also considers the variance risk premium embedded in the hedging instruments, enabling more informed and adaptive risk management. In this setting, state-dependent no-trade regions emerge naturally, improving rebalancing efficiency and hedging performance. Tested across simulated and historical data from 1996 to 2020, our method consistently outperforms traditional delta and delta-gamma hedging, demonstrating superior adaptability and risk reduction.