用波动率代理变量解释市场集体相关性的缓慢变化,发现其主要来自外部驱动而非内在惯性。
Conditioning on a Volatility Proxy Compresses the Apparent Timescale of Collective Market Correlation
- 通过将波动率(VIX)作为代理变量,显著压缩了市场相关性的有效弛豫时间。
- 模型拟合度提升显著,BIC降低109,其中对数波动率信息贡献最大。
- 结果在多种控制实验下稳定,适合研究金融系统非平衡动力学的学者。
针对市场集体动态中观察到的缓慢持久现象——其是内在特性还是源自持续驱动源?我们分析了标普500指数60日滚动相关矩阵的首特征值占比ψ₁=λₘₐₓ/N(237只股票,2004–2023年)。基于与VIX耦合的奥恩斯坦-乌伦贝克模型,有效弛豫时间从298个交易日缩短至61个交易日,相较纯均值回归模型的BIC改善达ΔBIC=109。在分解样本中,仅使用log(VIX)的信息残差即可保留大部分拟合增益(ΔBIC=78.6),而机械性VIX代理变量则无改进。自相关匹配的伪随机场不支持该结论(ΔBICₘₐₓ=2.7),跨周重构仍支持场耦合模型(ΔBIC=140–151),六个锚定时间点的外样本检验亦保持优势。平静期及去除场效应后的残差自相关控制显示持久性同样坍缩。更强的隐变量扩展仅部分支持。在测试的随机模型类中,条件于可观测的VIX代理变量可吸收绝大部分表观慢动态。
原文摘要 · Abstract (English)
We address the attribution problem for apparent slow collective dynamics: is the observed persistence intrinsic, or inherited from a persistent driver? For the leading eigenvalue fraction $ψ_1=λ_{\max}/N$ of S\&P 500 60-day rolling correlation matrices ($237$ stocks, 2004--2023), a VIX-coupled Ornstein--Uhlenbeck model reduces the effective relaxation time from $298$ to $61$ trading days and improves the fit over bare mean reversion by $Δ$BIC$=109$. On the decomposition sample, an informational residual of $\log(\mathrm{VIX})$ alone retains most of that gain ($Δ$BIC$=78.6$), whereas a mechanical VIX proxy alone does not improve the fit. Autocorrelation-matched placebo fields fail ($Δ$BIC$_{\max}=2.7$), disjoint weekly reconstructions still favor the field-coupled model ($Δ$BIC$=140$--$151$), and six anchored chronological holdouts preserve the out-of-sample advantage. Quiet-regime and field-stripped residual autocorrelation controls show the same collapse of persistence. Stronger hidden-variable extensions remain only partially supported. Within the tested stochastic class, conditioning on the observed VIX proxy absorbs most of the apparent slow dynamics.
Thank you to arXiv for use of its open access interoperability. PaperDance 不是 arXiv 官方产品;中文卡片由大模型生成,请以原文为准。