Originally posted by: 9tanki
I disagree with you completely. Polygraph test is used for screening new employee, hiring police department personnel and law enforcement agency people apart from finding truth during criminal investigation. If we start questioning one machine result is fake or unreliable then probably we have dump all the machines that we use in real life. Sensors that is used in polygraph test are also used by doctor, so does it mean all the doctor are cheating when they give medicine based on those result ? Why would anyone intentionally trick a machine when it will not help them in their final result.
Before a machine is build, they do 1000's of experiment to check it consistency and accuracy which is mentioned in the specification sheet and if it goes off then its recalibrated.
Even if its the most unreliable source of machine like you said, it is used by all the police department. I am sure police department don't use it for their own fun.
Just because some of the contestant on NB didnt the pass polygraph test doesnt mean such machines are fake or unreliable.