The popular systemic risk measure CoVaR (conditional Value-at-Risk) is widely used in economics and finance. Formally, it is defined as an (extreme) quantile of one variable (e.g., losses in the financial system) conditional on some other variable (e.g., losses in a bank's shares) being in distress and, hence, measures the spillover of risks. In this article, we propose joint dynamic and semiparametric models for VaR and CoVaR together with a two-step M-estimator for the model parameters drawing on recently proposed bivariate scoring functions for the pair (VaR, CoVaR). Among others, this allows for the estimation of joint dynamic forecasting models for (VaR, CoVaR). We prove consistency and asymptotic normality of the proposed estimator and analyze its finite-sample properties in simulations. We apply our dynamic models to generate CoVaR forecasts for real financial data, which are shown to be superior to existing methods.
翻译:在经济和金融中广泛使用流行的系统风险度量COVaR(有条件值风险值),在形式上,它被定义为一个变量(例如金融系统的损失)的一个(极端)量,条件是某些其他变量(例如银行股份损失)处于困境,从而衡量风险的溢出。在本条中,我们提出了VaR和CoVaR的动态和半参数联合模型,以及一个基于最近提议的双变量评分函数(VaR、CoVaR)的模型参数的双步M估测器。除其他外,这可以用来估计(VaR、CoVaR)的联合动态预测模型。我们证明拟议的估量器的一致性和无症状的正常性,并在模拟中分析其有限的抽样特性。我们用我们的动态模型对真实金融数据进行COVaR的预测,这些预测被证明优于现有方法。