65th ISI World Statistics Congress 2025

65th ISI World Statistics Congress 2025

A General Design-Based Framework and Estimator for Randomized Experiments

Author

FS
Fredrik Sävje

Co-author

  • F
    Fredrik Sävje
  • C
    Christopher Harshaw
  • Y
    Yitan Wang

Conference

65th ISI World Statistics Congress 2025

Format: IPS Abstract - WSC 2025

Keywords: causal inference, design-based,, experiments

Session: IPS 812 - Experimental and Observational Causal Inference in the Tech Industry

Monday 6 October 10:50 a.m. - 12:30 p.m. (Europe/Amsterdam)

Abstract

We describe a design-based framework for drawing causal inference in randomized experiments. Causal effects are defined as linear functionals evaluated at unit-level potential outcome functions. Assumptions about the potential outcome functions are encoded as function spaces. This makes the framework expressive, allowing experimenters to formulate and investigate a wide range of causal questions, including interference. We describe a class of estimators for estimands defined using the framework and investigate their properties. The construction of the estimators is based on the Riesz representation theorem. We provide necessary and sufficient conditions for unbiasedness and consistency. Finally, we provide conditions under which the estimators are asymptotically normal, and describe a conservative variance estimator to facilitate the construction of confidence intervals for the estimands.