Comment by nonrandomstring | Hacker News Reader

Comment by nonrandomstring | Hacker News Reader

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nonrandomstring

"The Lie Behind the Lie Detector" had a big impact on me [1]. As a kid I made lie detectors (a 9 volt battery, 1M-Ohm resistor, BC108 transistor and buzzer) and got sent home from school for "Interrogating" the other kids. The teacher evidently thought it really worked - even though as an 8 year old I knew it was just an electronic trick.

40 years later the Iraqi government was purchasing thousands of ADE 651 "bomb detectors" [2] - basically a stick - that no doubt caused some poor dudes to get blown to bits by IEDs.

All technology (indistinguishable from magic) has a cult-like aura around it, in that there's the reality of what it does, and a separate set of human beliefs about what it does. Cybersecurity is full of wishful and magical thinking in this regard. I sometimes feel like a kind of James Randi, trying to debunk the certainty people want and project on to technologies.

[1] https://antipolygraph.org/lie-behind-the-lie-detector.pdf

[2] https://www.cnet.com/culture/divining-rod-reborn-as-explosiv...

Ulgh, knowing the polygraph is a lie is actually a huge hazard for you.

I once had to take a polygraph test, and I was freaking the fuck out because I knew being nervous will register me as a liar, and I wasn't actually lying at all. I tried my best to stay calm, but I was freaking out during the test, and I actually did fail the polygraph, but passed after a retest.

It's such bullshit. I wish they got rid of this bullshit technology from this earth, because I had so much on the line and I was absolutely miserable before and during the test.

I am sorry you had to go through that, but why would you take it if you knew it was scientifically unsound? I would just say "no, this is scientifically unsound" and refuse to participate. They're going to "detect" whatever they want from my words and punish me accordingly, so I might as well say nothing.

Well, because you don't get a choice, if you don't take it then you don't get what you want (for example, a security clearance or a job), it tends to be a non-negotiable requirement.

You wouldn't get a criminal conviction by refusing to participate, but in other contexts refusal to participate can be (and is) treated the same as failing it.

Ah yes, the good old security clearance polygraph. My friend failed that one 3 times through nervousness. I believe that whole process is just partly to make you nervous and off-balance while they ask you probing questions and partly to signal that you, as an applicant, are willing to ask "how high?" when the government says jump. I did a few clearance processes when I was in the military, ultimately got a TS-SCI, but never took a polygraph; I think because I had a clean-as-a-sheet record since I joined the military a week after my 18th birthday.

It's a compliance test.

If you'll take a polygraph (or engage in any other witchcraft ritual) then you're probably malleable enough to do other dumb things against your better judgement.

In other words you'll act dishonestly to please others or advance yourself. That is to say - it really is a lie detector, just one for seeing how well you can lie to yourself.

Every few years I come across this statement about polygraphs. I want so much to learn about them and how to “beat them.” But every time I look into it, it’s a 300-page book to read or a 4+ hour video commitment.

Why?

Here's the TLDR; polygraph tests really test for stress indictators. If you think they work and you generally stress out when lieing, and you really dwell on the 'oh my gosh, they're going to know I lied, because of the test and I just lied', your stress indicators will be off the chart, and there you go.

If you know they're bunk, and so you can lie without stressing out, then they won't detect stress, especially if you've practiced with a polygraph. But, they usually do some sort of calibration. If you're calm or stressed the whole test, the results are inconclusive. You want to be calm when giving most of your answers, but stressed during the calibration questions where they expect you to be stressed.

The only reason you should submit to a polygraph if is if you want clearance in the US. Or you want to be a on a trashy talk show (eh, someone's gotta be on those, I guess). Anywhere else, stick to your guns and refuse on the basis that they're not reliable and it's a waste of everyone's time; don't be goaded into the 'well if they don't mean anything, why don't you just take it'

Of course, sometimes you might find yourself in a situation where the easiest path to what you want is through a polygraph, and it's easier for me to say don't take it, than for you to refuse.... like, do your best, I guess?

Thank you!!

I vote for a trashy talk show full of HN crowd. Optionally with everyone on polygraphs.

The "real" TLDR (and I am not kidding here!) is that you clinch your anus during every answer. It does something to your heartrate, blood pressure, etc. that makes lies indistinguishable from the truth. Also polygraphers know this and will call you out on it if they think you are doing it. It makes all of your answers register the same and they assume that you will lie on at least one as a baseline (usually something like "have you ever told a lie in your life" or something similar).

Thank you. I had not heard of this product before. I want one.

https://en.wikipedia.org/wiki/ADE_651

> According to Iraqi police officer Jasim Hussein, "The vast majority of the people we stop, it's because of their perfume". A fellow officer, Hasan Ouda, commented that "Most people now understand it's what gets them searched, so they don't use as much."

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