Analysis & Applied Math

Event Information Adapting Real-World A/B Experimentation using Machine Learning: Balancing Enhancement of User Experiences with Statistically Robust Scientific Discovery
14:10 on Friday October 11, 2024
15:00 on Friday October 11, 2024
BA6183, Bahen Center, 40 St. George St.
Joseph Jay Williams
https://www.psych.utoronto.ca/people/directories/all-faculty/joseph-jay-williams
University of Toronto

How can we transform the everyday technology people use into intelligent, self-improving systems? For example, how can we perpetually enhance text messages for managing stress, or personalize explanations in online courses? Our work explores the use of randomized adaptive experiments that test alternative actions (e.g. text messages, explanations), aiming to gain greater statistical confidence about the value of actions, in tandem with rapidly using this data to give better actions to future users. To help characterize the problems that arise in statistical analysis of data collected while trading off exploration and exploitation, we present a real-world case study of applying the machine learning multi-armed bandit algorithm TS (Thompson Sampling) to adaptive experiments, providing more empirical context to issues raised by past work on adaptive clinical trials. We also conduct field deployments and provide software the community can use to evaluate statistical tests and algorithms in complex real-world applications. This helps provide first steps towards integrating two key approaches: (1) How can we modify statistical tests to better match the properties of the algorithms that collect data in adaptive experiments? (2) How can we modify algorithms for adaptive experimentation to be more "statistically considerate" in being better suited to inference and analysis of data, while maximizing chances of giving participants useful arms? Tackling these questions requires multidisciplinary collaboration between researchers in machine learning, statistics, and the social-behavioral sciences. This is joint work with Nina Deliu, Sofia Villar, Audrey Durand, Anna Rafferty and others. The PhD students leading this are Tong Li and Fred Haochen Song.