An empirical evaluation of active inference in multi-armed bandits

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

Abstract

A key feature of sequential decision making under uncertainty is a need to balance between exploiting—choosing the best action according to the current knowledge, and exploring—obtaining information about values of other actions. The multi-armed bandit problem, a classical task that captures this trade-off, served as a vehicle in machine learning for developing bandit algorithms that proved to be useful in numerous industrial applications. The active inference framework, an approach to sequential decision making recently developed in neuroscience for understanding human and animal behaviour, is distinguished by its sophisticated strategy for resolving the exploration–exploitation trade-off. This makes active inference an exciting alternative to already established bandit algorithms. Here we derive an efficient and scalable approximate active inference algorithm and compare it to two state-of-the-art bandit algorithms: Bayesian upper confidence bound and optimistic Thompson sampling. This comparison is done on two types of bandit problems: a stationary and a dynamic switching bandit. Our empirical evaluation shows that the active inference algorithm does not produce efficient long-term behaviour in stationary bandits. However, in the more challenging switching bandit problem active inference performs substantially better than the two state-of-the-art bandit algorithms. The results open exciting venues for further research in theoretical and applied machine learning, as well as lend additional credibility to active inference as a general framework for studying human and animal behaviour.

Details

Original languageEnglish
Pages (from-to)229-246
Number of pages18
JournalNeural Networks
Volume144
Publication statusPublished - Dec 2021
Peer-reviewedYes

External IDs

Scopus 85114787792

Keywords

Keywords

  • Active inference, Bayesian inference, Decision making, Multi-armed bandits, Thompson sampling, Upper confidence bound