The application of semiparametric efficient estimators, particularly those that leverage machine learning, is rapidly expanding within epidemiology and causal inference. This literature is increasingly invoking the Riesz representation theorem and Riesz regression. This paper aims to introduce the Riesz representation theorem to an epidemiologic audience, explaining what it is and why it's useful, using step-by-step worked examples.

翻译：半参数有效估计器（尤其是那些利用机器学习的估计器）在流行病学和因果推断领域的应用正在迅速扩展。相关文献越来越多地涉及Riesz表示定理和Riesz回归。本文旨在向流行病学研究者介绍Riesz表示定理，通过逐步演算的实例，阐释其基本概念与应用价值。