Low Risk, High Variability: Practical Guide for Portfolio Construction
研究了不同投资组合构建方法对低风险策略表现的影响，发现方法选择导致绩效差异大，波动率估计优于贝塔估计，交易成本显著影响排名，为投资者构建可靠低风险组合提供实用指导。
The article examines how various portfolio construction choices influence the performance of low-risk strategies, and shows that methodological decisions critically influence portfolio outcomes, causing substantial dispersion in performance metrics across weighting schemes and risk estimators. Constraints such as short-sale restrictions and size or price filters reduce this variation only marginally. Volatility-based risk estimators yield the most favorable results, outperforming beta-based approaches. A further finding is that transaction costs significantly affect performance rankings, underscoring the need to evaluate strategies under realistic implementation assumptions. The article provides practical guidance for investors seeking to build more reliable low-risk portfolios and to limit nonstandard errors in portfolio design.