cs.AIOct 11, 2026

Vision: "What Don't I Know About User's Preferences?" How Uncertainty Estimation Improves Proactive Assistant Alignment

Authors: Zhiyu An, Ziyi Xuan, Yu Yang, Wan Du

Organizations: University of California, Merced Merced, California, USA · Lehigh University Bethlehem, Pennsylvania USA

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Abstract

Proactive Smart Assistants (PSAs) increasingly use general knowledge, learned patterns from group-level data, patterns from individual user's data, and recent sensor observations to anticipate which action a user may prefer. Existing systems typically select actions from predicted user preference likelihoods, but these likelihoods alone do not reveal how reliable the prediction is, which evidence supports it, or why ambiguity remains. In this vision paper, we argue that uncertainty estimation can provide this missing information and substantially change appropriate downstream behavior. Using the example of a home assistant, we introduce the questions that uncertainty estimation aims to answer, i.e. how sure is the assistant about the predicted preference likelihood, whether the confidence come from group-level assumptions or individual's data, and whether likelihood ambiguity reflect the user's intrinsic preference variability or insufficient data for the particular situation. We further introduce uncertainty estimation applications in neighboring domains, such as human trajectory prediction, personalized activity recognition, information-collection, and model-based control. Finally, we draw on insights from neighboring domains to envision how future uncertainty-aware proactive assistants may address key challenges in proactive interaction.

Figures & tables

Figure 1. Uncertainty estimation can substantially inform proactive assistant and change its proper downstream actions.
Figure 2. Future uncertainty-aware proactive assistants may respond differently to the same predicted preference likelihoods depending on the source of uncertainty.
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