A variant of The Aumann Game where one player purposefully subverts the group estimate. Similar to The Aumann Game, the activity consists of a group jointly producing a confidence interval for an unknown, but verifiable quantity, which is then scored for accuracy and calibration. However, before the activity begins, one individual is secretly assigned the role of misleading the other members. The deceiver is scored higher the worse the final estimate is.
The activity is intended to teach accurate estimate, proper agreement techniques, and recognition of deception.