# I Know What You Meant: Learning Human Objectives by (Under)estimating Their Choice Set

arXiv: https://arxiv.org/abs/2011.06118 · HTML: https://mlsanity.com/paper/2011.06118/

## Key facts

- Cited by 9 papers in the map (data through 14 Oct 2026).
- First posted on arXiv 11 Nov 2020.

## Built on by (most cited first, 9 of 9)

- [The Effect of Modeling Human Rationality Level on Learning Rewards from Multiple Feedback Types](https://mlsanity.com/paper/2208.10687/) (2022)
- [Physical Interaction as Communication: Learning Robot Objectives Online from Human Corrections](https://mlsanity.com/paper/2107.02349/) (2021)
- [VIEW: Visual Imitation Learning with Waypoints](https://mlsanity.com/paper/2404.17906/) (2024)
- [Open-Ended Goal Inference through Actions and Language for Human-Robot Collaboration](https://mlsanity.com/paper/2512.04453/) (2025)
- [Autonomous Assessment of Demonstration Sufficiency via Bayesian Inverse Reinforcement Learning](https://mlsanity.com/paper/2211.15542/) (2022)
- [Bayesian inference for data-efficient, explainable, and safe robotic motion planning: A review](https://mlsanity.com/paper/2307.08024/) (2023)
- [Combining Bayesian Inference and Reinforcement Learning for Agent Decision Making: A Review](https://mlsanity.com/paper/2505.07911/) (2025)
- [Robots Influencing Humans to Reveal their Goals during Collaboration and Competition](https://mlsanity.com/paper/2609.05519/) (2026)
- [Using High-Level Patterns to Estimate How Humans Predict a Robot will Behave](https://mlsanity.com/paper/2409.13533/) (2024)

## Abstract (arXiv)

Assistive robots have the potential to help people perform everyday tasks. However, these robots first need to learn what it is their user wants them to do. Teaching assistive robots is hard for inexperienced users, elderly users, and users living with physical disabilities, since often these individuals are unable to show the robot their desired behavior. We know that inclusive learners should give human teachers credit for what they cannot demonstrate. But today's robots do the opposite: they assume every user is capable of providing any demonstration. As a result, these robots learn to mimic the demonstrated behavior, even when that behavior is not what the human really meant! Here we propose a different approach to reward learning: robots that reason about the user's demonstrations in the context of similar or simpler alternatives. Unlike prior works -- which err towards overestimating the human's capabilities -- here we err towards underestimating what the human can input (i.e., their choice set). Our theoretical analysis proves that underestimating the human's choice set is risk-averse, with better worst-case performance than overestimating. We formalize three properties to generate similar and simpler alternatives. Across simulations and a user study, our resulting algorithm better extrapolates the human's objective. See the user study here: https://youtu.be/RgbH2YULVRo
