Personalization Aids Pluralistic Alignment Under Competition

TL;DR

This paper demonstrates that personalization among competing AI providers can lead to outcomes aligned with diverse user preferences, even when providers are self-interested, by modeling their interaction as a strategic game.

Contribution

It introduces a game-theoretic model showing how personalization enables pluralistic alignment under competition, contrasting with the limitations of anonymous policies.

Findings

Personalization achieves outcomes comparable to a perfectly aligned model.

Anonymous policies can lead to uninformative equilibria.

Stronger conditions guarantee optimal user utility even without personalization.

Abstract

Can competition among misaligned AI providers yield aligned outcomes for a diverse population of users, and what role does model personalization play? We study a setting where multiple competing AI providers interact with multiple users who must make downstream decisions but differ in preferences. Providers have their own objectives over users' actions and strategically deploy AI models to advance them. We model the interaction as a Stackelberg game with multiple leaders (providers) and followers (users): providers commit to conversational policies, and users choose which model to use, how to converse, and how to act. With user-specific personalization, we show that under a Weak Market Alignment condition, every equilibrium gives each user outcomes comparable to those from a perfectly aligned common model -- so personalization can induce pluralistically aligned outcomes, even when providers are self-interested. In contrast, when providers must deploy a single anonymous policy, there exist equilibria with uninformative behavior under the same condition. We then give a stronger alignment condition that guarantees each user their optimal utility in the anonymous setting.