A physics research team has members who can (and occasionally do) in secret insert false signals into the experiment the team is running. The goal is practice resistance to false positives. A very interesting approach, first time I've heard about physicists using it.

Bias combat in action :-)

The LIGO is almost unique among physics experiments in practising ‘blind injection’. A team of three collaboration members has the ability to simulate a detection by using actuators to move the mirrors. “Only they know if, and when, a certain type of signal has been injected,”...

Two such exercises took place during earlier science runs of LIGO, one in 2007 and one in 2010. ... The original blind-injection exercises took 18 months and 6 months respectively. The first one was discarded, but in the second case, the collaboration wrote a paper and held a vote to decide whether they would make an announcement. Only then did the blind-injection team ‘open the envelope’ and reveal that the events had been staged.

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