Robust Spatial-Sign-Based Testing of High-Dimensional Alpha in Conditional Factor Models
条件因子模型中高维 Alpha 的稳健空间符号检验
This paper develops a new framework for alpha testing in high-dimensional factor pricing models with time-varying coefficients. To detect sparse alternatives, we propose a spatial-sign-based max-type test and derive its limiting null distribution. A key theoretical result is that our statistic is asymptotically independent of the spatial-sign-based sum-type test proposed by Zhao (2023). Exploiting this independence, we construct an adaptive testing procedure via the Cauchy…