🤖 AI Summary
Constructing efficient debiased estimators traditionally requires manual derivation of the efficient influence function (EIF), a labor-intensive process with high technical barriers and poor scalability.
Method: This paper introduces Dimple, the first framework that models statistical functionals as compositions of differentiable primitives satisfying a novel differentiability condition; it leverages automatic differentiation to directly generate unbiased, efficient estimators while simultaneously identifying nuisance parameters. Dimple integrates probabilistic programming with functional decomposition, eliminating the need for explicit EIF derivation.
Contribution/Results: We provide an open-source Python library enabling users to define parameters, generate estimators, and perform inference in just a few lines of code. Extensive experiments demonstrate Dimple’s effectiveness across diverse causal and semiparametric models—including AIPW, DR-Learner, and doubly robust IV—significantly lowering the barrier to constructing efficient estimators without sacrificing statistical efficiency.
📝 Abstract
We introduce an algorithm that simplifies the construction of efficient estimators, making them accessible to a broader audience. 'Dimple' takes as input computer code representing a parameter of interest and outputs an efficient estimator. Unlike standard approaches, it does not require users to derive a functional derivative known as the efficient influence function. Dimple avoids this task by applying automatic differentiation to the statistical functional of interest. Doing so requires expressing this functional as a composition of primitives satisfying a novel differentiability condition. Dimple also uses this composition to determine the nuisances it must estimate. In software, primitives can be implemented independently of one another and reused across different estimation problems. We provide a proof-of-concept Python implementation and showcase through examples how it allows users to go from parameter specification to efficient estimation with just a few lines of code.