Reply #4: If you want to educate yourself on the polygraph

[Columbia]

Check this out: http://www.antipolygraph.org/lie-behind-the-lie-detector.pdf

There is a reason why polygraphs are not admissible in court, federal law prohibits businesses from using them for pre-employment screening and the National Academy of Sciences declared them harmful to national security.

DISCLAIMER: Knowing the deception behind the polygraph may inadvertently affect it's effectiveness and may be detrimental to passing, so peruse at your risk.