Pessimistic Off-Policy Optimization for Learning to Rank

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Cief, Matej, Kveton, Branislav, Kompan, Michal
Format: Preprint
Veröffentlicht: 2022
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866916448134234112
author Cief, Matej
Kveton, Branislav
Kompan, Michal
author_facet Cief, Matej
Kveton, Branislav
Kompan, Michal
contents Off-policy learning is a framework for optimizing policies without deploying them, using data collected by another policy. In recommender systems, this is especially challenging due to the imbalance in logged data: some items are recommended and thus logged more frequently than others. This is further perpetuated when recommending a list of items, as the action space is combinatorial. To address this challenge, we study pessimistic off-policy optimization for learning to rank. The key idea is to compute lower confidence bounds on parameters of click models and then return the list with the highest pessimistic estimate of its value. This approach is computationally efficient, and we analyze it. We study its Bayesian and frequentist variants and overcome the limitation of unknown prior by incorporating empirical Bayes. To show the empirical effectiveness of our approach, we compare it to off-policy optimizers that use inverse propensity scores or neglect uncertainty. Our approach outperforms all baselines and is both robust and general.
format Preprint
id arxiv_https___arxiv_org_abs_2206_02593
institution arXiv
publishDate 2022
record_format arxiv
spellingShingle Pessimistic Off-Policy Optimization for Learning to Rank
Cief, Matej
Kveton, Branislav
Kompan, Michal
Machine Learning
Artificial Intelligence
Information Retrieval
Off-policy learning is a framework for optimizing policies without deploying them, using data collected by another policy. In recommender systems, this is especially challenging due to the imbalance in logged data: some items are recommended and thus logged more frequently than others. This is further perpetuated when recommending a list of items, as the action space is combinatorial. To address this challenge, we study pessimistic off-policy optimization for learning to rank. The key idea is to compute lower confidence bounds on parameters of click models and then return the list with the highest pessimistic estimate of its value. This approach is computationally efficient, and we analyze it. We study its Bayesian and frequentist variants and overcome the limitation of unknown prior by incorporating empirical Bayes. To show the empirical effectiveness of our approach, we compare it to off-policy optimizers that use inverse propensity scores or neglect uncertainty. Our approach outperforms all baselines and is both robust and general.
title Pessimistic Off-Policy Optimization for Learning to Rank
topic Machine Learning
Artificial Intelligence
Information Retrieval
url https://arxiv.org/abs/2206.02593