🤖 AI Summary
This study addresses the limitations of traditional hedging strategies under market dynamics uncertainty, which often suffer from excessive risk exposure and high turnover. The authors propose a robust dynamic minimum-variance hedging framework that explicitly incorporates volatility forecast uncertainty into the optimization process, yielding closed-form robust hedge ratios. The approach integrates high-frequency realized variances and covariances, multi-step autoregressive volatility forecasts, and box-type uncertainty sets within a robust optimization setting. Empirical analysis using multiple ETFs from 2016 to 2024 demonstrates that the proposed framework significantly reduces portfolio turnover, enhances protection against downside risk, and improves risk-adjusted returns after accounting for transaction costs. Statistical significance of these results is confirmed through bootstrap tests.
📝 Abstract
Shorting for hedging exposes to risk when the market dynamics is uncertain. Managing uncertainty and risk exposure is key in portfolio management practice. This paper develops a robust framework for dynamic minimum-variance hedging that explicitly accounts for forecast uncertainty in volatility estimation to achieve empirical stability and reduced turnover, further improving other standard performance metrics. The approach combines high-frequency realized variance and covariance measures, autoregressive models for multi-step volatility forecasting, and a box-uncertainty robust optimization scheme. We derive a closed-form solution for the robust hedge ratio, which adjusts the standard minimum-variance hedge by incorporating variance forecast uncertainty. Using a diversified sample of equity, bond, and commodity ETFs over 2016-2024, we show that robust hedge ratios are more stable and entail lower turnover than standard dynamic hedges. While overall variance reduction is comparable, the robust approach improves downside protection and risk-adjusted performance, particularly when transaction costs are considered. Bootstrap evidence supports the statistical significance of these gains.