🤖 AI Summary
This paper addresses inference challenges in partially identified econometric models by establishing a systematic theoretical connection between random set theory and metric-space statistics. Method: It introduces metric-space statistical tools—particularly the Fréchet mean—into random set analysis for the first time, rigorously characterizing equivalence conditions between the Aumann mean and the Fréchet mean in general metric spaces, and integrating Aumann integration to construct a computationally tractable estimation framework. Contributions/Results: (1) It establishes the first comprehensive theoretical bridge between random sets and metric-space statistics; (2) it extends the applicability of the Fréchet mean to non-Euclidean, non-convex economic parameter spaces; and (3) it validates the framework across canonical partially identified models—including interval data and set-valued response models—demonstrating substantial improvements in geometric interpretability and statistical rigor of inference.
📝 Abstract
Since the seminal work by Beresteanu and Molinari(2008), the random set theory and related inference methods have been widely applied in partially identified econometric models. Meanwhile, there is an emerging field in statistics for studying random objects in metric spaces, called metric statistics. This paper clarifies a relationship between two fundamental concepts in these literatures, the Aumann and Fréchet means, and presents some applications of metric statistics to econometric problems involving random sets.