第一部分：纸牌游戏出千 · Card Switching
Mechanical Holdout
工作原理
A mechanical holdout is a device worn on the person. It keeps one or more cards out of the game and brings them back when wanted. The hand looks empty. The cards are not in it. This is not hand mucking, which hides cards in the palm. The machine does the hiding.
出现场合
Poker, and other games in which a player handles cards
有据可查
John Nevil Maskelyne describes mechanical holdouts in Sharps and Flats (1894). This entry uses that book. It does not attach a modern case.
识别与防范建议
付费部分监控室如何识别mechanical holdout，以及如何防止其再次发生——为值班人员而写，而非为普通读者。
本文作为监控、合规及博彩营运专业人员的侦测参考发布。阈值与调校由各家娱乐场自行设定。本文不构成任何操作指引：描述该方法的目的仅在于使其能够被识别。