Machine Teaching for Human Inverse Reinforcement Learning
Abstract
As robots continue to acquire useful skills, their ability to teach their expertise will provide humans the two-fold benefit of learning from robots and collaborating fluently with them. For example, robot tutors could teach handwriting to individual students and delivery robots could convey their navigation conventions to better coordinate with nearby human workers. Because humans naturally communicate their behaviors through selective demonstrations, and comprehend others’ through reasoning that resembles inverse reinforcement learning (IRL), we propose a method of teaching humans based on demonstrations that are informative for IRL. But unlike prior work that optimizes solely for IRL, this paper incorporates various human teaching strategies (e.g. scaffolding, simplicity, pattern discovery, and testing) to better accommodate human learners. We assess our method with user studies and find that our measure of test difficulty corresponds well with human performance and confidence, and also find that favoring simplicity and pattern discovery increases human performance on difficult tests. However, we did not find a strong effect for our method of scaffolding, revealing shortcomings that indicate clear directions for future work.
This work was supported by the Office of Naval Research award N00014-18-1-2503 and Defense Advanced Research Projects Agency (DARPA)/Army Research Office (ARO) award W911NF-20-1-0006. The views and conclusions contained in this document are of the authors and should not be interpreted as representing official policies, expressed or implied, of DARPA, ARO, or U.S. Government. The U.S. Government is authorized to reproduce and distribute reprints for government purposes notwithstanding any copyright notation herein. We would like to thank Vignesh Rajmohan and Meghna Behari for their assistance in creating the user study, and Pallavi Koppol for serving as an independent coder and for sharing her user study and data analysis templates.
BibTeX
@article{Lee-2021-128194,author = {Michael S. Lee and Henny Admoni and Reid Simmons},
title = {Machine Teaching for Human Inverse Reinforcement Learning},
journal = {Frontiers in Robotics and AI},
year = {2021},
month = {June},
keywords = {inverse reinforcement learning, learning from demonstration, scaffolding, policy summarization, machine teaching},
}