Paper: arXiv 2406.06860

Authors: Chen Tong, Peter Reinhard Hansen, Ilya Archakov

Abstract

We introduce a novel multivariate GARCH model with flexible convolution-t distributions that is applicable in high-dimensional systems. The model is called Cluster GARCH because it can accommodate cluster structures in the conditional correlation matrix and in the tail dependencies. The expressions for the log-likelihood function and its derivatives are tractable, and the latter facilitate a score-drive model for the dynamic correlation structure. We apply the Cluster GARCH model to daily returns for 100 assets and find it outperforms existing models, both in-sample and out-of-sample. Moreover, the convolution-t distribution provides a better empirical performance than the conventional multivariate t-distribution.

Complexity vs Empirical Score

  • Math Complexity: 8.0/10
  • Empirical Rigor: 8.5/10
  • Quadrant: Holy Grail — high math complexity, high empirical rigor

Why this score: The paper makes a strong contribution by integrating convolution-t heavy-tailed distributions into a score-driven multivariate GARCH model using a tractable block correlation matrix. The empirical rigor is outstanding, featuring both in-sample and out-of-sample backtests up to 100 assets, backed by sound statistical derivations for the likelihood score and information matrices.

Research Flowchart

  flowchart TD
    A[Goal: High-dimensional multivariate GARCH model with flexible tail dependencies] --> B[Data: Daily returns of 100 equity assets]
    B --> C[Method: Cluster GARCH with Convolution-t Distributions]
    C --> D[Compute Tractable Log-Likelihood & Score Derivatives]
    D --> E[Model Dynamic Correlations & Cluster Structures]
    E --> F[Outperforms Existing Models & Multivariate t-Distribution In/Out-of-Sample]