Teams without communication learn from how enemies react to them
How a group that cannot communicate knows itself by its enemy
Computer Science and Game TheoryMultiagent SystemsRobotics
Summary
Sometimes, groups can’t talk to each other but still need to share information. This paper shows how an opposing side’s reactions can actually tell the group what each person alone can’t know. By deciding in advance how to respond to the opponent, the group can learn more, even when the opponent tries to hide information. The researchers also explain when it’s better for the team to trust less and how different team members’ responses help gather truth.
What this means in practice
- •For robotic swarm operators: Coordinate a group of robots that cannot directly communicate by interpreting the behavior of a shared adversary to gain missing information.
- •For security protocol designers: Design secure protocols that rely on adversary actions as indirect communication channels when direct communication is blocked or risky.
A theory result. No direct application yet.
Authors
Gregory Falco
Abstract
Teams that cannot communicate seem stuck with what each member sees. We show that their opponent can tell them the rest. Silent hunters, jammed robots and traders who never meet all face an adversary that reacts to the group as a whole; every member can read that reaction, a tell, and learn what no member knows alone. One tell can do the work of a message from every member. The adversary would rather hide, but hiding interferes with its own task, and a team that commits in advance to how it will respond decides how much hiding is worth. A committed team never loses when its opponent cares more about its own goals, and does as well as a fully informed team exactly when the opponent's stake outweighs any gain from lying. Below that point the team learns more by trusting less: in a solved Gaussian model it obtains the truth by promising not to use all of it and keeps the cost the opponent would have paid to conceal; an exact test decides when this holds in finite games. How a team spreads its trust matters too. A lone uninformed member with a full-support prior needs a private coin, but with additive squared-error losses two interchangeable members who respond differently replace it, and a small discount on trust insures against misjudging the enemy. Information, on this view, is not only gathered or aggregated; it is produced by how a team commits to respond.