Skip to Content

Search: {{$root.lsaSearchQuery.q}}, Page {{$root.page}}

Statistics Department Seminar Series: Susan Murphy, Mallinckrodt Professor of Statistics and of Computer Science, Radcliffe Alumnae Professor at the Radcliffe Institute, Harvard University

Friday, March 31, 2023
10:00-11:00 AM
340 West Hall Map
"Inference for Longitudinal Data After Adaptive Sampling"

Abstract: Adaptive sampling methods, such as reinforcement learning (RL) and bandit algorithms, are increasingly used for the real-time personalization of interventions in digital applications like mobile health and education. As a result, there is a need to be able to use the resulting adaptively collected user data to address a variety of inferential questions, including questions about time-varying causal effects. However, current methods for statistical inference on such data (a) make strong assumptions regarding the environment dynamics, e.g., assume the longitudinal data follows a Markovian process, or (b) require data to be collected with one adaptive sampling algorithm per user, which excludes algorithms that learn to select actions using data collected from multiple users. These are major obstacles preventing the use of adaptive sampling algorithms more widely in practice. In this work, we proved statistical inference for the common Z-estimator based on adaptively sampled data. The inference is valid even when observations are non-stationary and highly dependent over time, and (b) allow the online adaptive sampling algorithm to learn using the data of all users. Furthermore, our inference method is robust to miss-specification of the reward models used by the adaptive sampling algorithm. This work is motivated by our work in designing the Oralytics oral health clinical trial in which an RL adaptive sampling algorithm will be used to select treatments, yet valid statistical inference is essential for conducting primary data analyses after the trial is over.

http://people.seas.harvard.edu/~samurphy/
Building: West Hall
Event Type: Workshop / Seminar
Tags: Physics
Source: Happening @ Michigan from Michael Woodroofe Lecture Series, Department of Statistics, Department of Statistics Seminar Series