Multi-layer Co-jump Network Under Market Asymmetric Jumps
摘要
In this paper, we propose a method to construct a multi-layer co-jump network based on a multi-layer degree-corrected stochastic block model, aims to infer risk propagation pathways from stock co‑jump patterns. Through the high-frequency price data, we extract the co-jump matrix of stocks during the positive and negative market jumps respectively, and set thresholds to construct a two-layer co-jump network. On this basis, the multi-layer normalized spectral clustering community detection algorithm is used to group stocks and identify stock communities with systematic risk correlation. The empirical results show that, compared with the single-layer co-jump network, the multi-layer co-jump network can capture a more stable and detailed community structure. The investment portfolio constructed according to this structure shows superior risk-adjusted returns, while significantly outperforming the market benchmark. These findings verify the practical value of the multi-layer co-jump network in risk management and asset allocation.