Statistical Seminar: Every Monday at 2:00 pm.
Time: 2:00 pm – 3:15 pm
Date: 22th January of 2024
Place : 3001

Eugène Ndiaye (Apple Research) – Finite Sample Confidence Sets with “Minimal” Assumptions on the Distribution

Abstract:

If you predict a label y of a new object with $\hat{y}$, how confident are you that ”y = $\hat{y}$”? The conformal prediction method provides an elegant framework for answering such a question by establishing a confidence set for an unobserved response of a feature vector based on previous similar observations of responses and features. This is performed without assumptions about the distribution of the data. While providing strong coverage guarantees, computing conformal prediction sets requires adjusting a predictive model to an augmented dataset considering all possible values that the unobserved response can take, and proceeding to select the most likely ones. For a regression problem where y is a continuous variable, it typically requires an infinite number of model fits; which is usually infeasible. By assuming a little more regularity in the underlying prediction models, I will describe some of the techniques that make the calculations feasible. Along similar lines, it can be assumed that we are working with a parametric model that explains the relation between input and output variables. Consequently, a natural question arises as to whether a confidence interval on the ground truth parameter of the model can be constructed, also without assumptions on the distribution of the data. In this presentation, I will provide a partial answer to the question with some preliminary results. This is mostly an ongoing project, with still a lot of open questions that I am eager to discuss and share insights for future work.

page web https://eugenendiaye.github.io/

Organizers:
Cristina BUTUCEA (CREST), Anna KORBA (CREST), Karim LOUNICI (CMAP) , Jaouad MOURTADA (CREST)
Sponsors:
CREST-CMAP