We develop methodology and theory for a general Bayesian approach towards dynamic variable selection in high-dimensional regression models with time-varying parameters. Specifically, we propose a variational inference scheme which features dynamic sparsity-inducing properties so that different subsets of ``active'' predictors can be identified over different time periods. We compare our modeling framework against established static and dynamic variable selection methods both in simulation and within the context of two common problems in macroeconomics and finance: inflation forecasting and equity returns predictability. The results show that our approach helps to tease out more accurately the dynamic impact of different predictors over time. This translates into significant gains in terms of out-of-sample point and density forecasting accuracy. We believe our results highlight the importance of taking a dynamic approach towards variable selection for economic modeling and forecasting.
翻译:----
我们针对具有时间变化参数的高维回归模型,提出了基于贝叶斯方法的动态变量选择的方法和理论。具体来说,我们提出了一种变分推断方案,具有动态稀疏诱导属性,因此可以在不同的时间段内确定不同的“活动”预测变量子集。我们将我们的建模框架与已建立的静态和动态变量选择方法进行了比较,包括在宏观经济学和金融领域内的两个常见问题:通胀预测和股票收益可预测性。结果表明,我们的方法有助于准确分离出不同预测变量随时间变化的动态影响。这意味着在样本外点和密度预测准确性方面可以取得显著的收益。我们相信我们的结果突显了在经济建模和预测中采取动态变量选择方法的重要性。