A Simple Method for Predicting Covariance Matrices of Financial Returns
We consider the well-studied problem of predicting the time-varying covariance matrix of a vector of financial returns. Popular methods range from simple predictors like rolling window or exponentially weighted moving average (EWMA) to more sophisticated predictors such as generalized autoregressive conditional heteroscedastic (GARCH) type methods. Building on a specific covariance estimator suggested by Engle in 2002, we propose a relatively simple extension that requires little or no tuning or fitting, is interpretable, and produces results at least as good as MGARCH, a popular extension of GARCH that handles multiple assets. To evaluate predictors we introduce a novel approach, evaluating the regret of the log-likelihood over a time period such as a quarter. This metric allows us to see not only how well a covariance predictor does over all, but also how quickly it reacts to changes in market conditions. Our simple predictor outperforms MGARCH in terms of regret. We also test covariance predictors on downstream applications such as portfolio optimization methods that depend on the covariance matrix. For these applications our simple covariance predictor and MGARCH perform similarly.
Code (1)
Tasks
Portfolio OptimizationMethods 이 논문이 사용한 방법론
Similar Papers 제목 키워드 기반
Expert Opinions and Logarithmic Utility Maximization for Multivariate Stock Returns with Gaussian Drift
This paper investigates optimal trading strategies in a financial market with multidimensional stock returns where the drift is an unobservable multivariate Ornstein-Uhlenbeck process. Information about the drift is obta…
Scalable Bayesian dynamic covariance modeling with variational Wishart and inverse Wishart processes
We implement gradient-based variational inference routines for Wishart and inverse Wishart processes, which we apply as Bayesian models for the dynamic, heteroskedastic covariance matrix of a multivariate time series. Th…
Gaussian ProcessesTime SeriesTime Series AnalysisVariational InferenceA Canonical Representation of Block Matrices with Applications to Covariance and Correlation Matrices
We obtain a canonical representation for block matrices. The representation facilitates simple computation of the determinant, the matrix inverse, and other powers of a block matrix, as well as the matrix logarithm and t…
Deep Reinforcement Learning for Asset Allocation in US Equities
Reinforcement learning is a machine learning approach concerned with solving dynamic optimization problems in an almost model-free way by maximizing a reward function in state and action spaces. This property makes it an…
Deep Reinforcement LearningManagementreinforcement-learningReinforcement Learning+4Constructing Analytically Tractable Ensembles of Non-Stationary Covariances with an Application to Financial Data
In complex systems, crucial parameters are often subject to unpredictable changes in time. Climate, biological evolution and networks provide numerous examples for such non-stationarities. In many cases, improved statist…