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Researchers Built an 'Online Lie Detector.' Honestly, That Could Be a Problem (wired.com)

A group of researchers claims to have built a prototype for an "online polygraph" that uses machine learning to detect deception from text alone. But as a few machine learning academics point out, what these researchers have actually demonstrated is the inherent danger of overblown machine learning claims. From a report: When Wired showed the study to a few academics and machine learning experts, they responded with deep skepticism. Not only does the study not necessarily serve as the basis of any kind of reliable truth-telling algorithm, it makes potentially dangerous claims: A text-based "online polygraph" that's faulty, they warn, could have far worse social and ethical implications if adopted than leaving those determinations up to human judgment.

"It's an eye-catching result. But when we're dealing with humans, we have to be extra careful, especially when the implications of whether someone's lying could lead to conviction, censorship, the loss of a job," says Jevin West, a professor at the Information School at the University of Washington and a noted critic of machine learning hype. "When people think the technology has these abilities, the implications are bigger than a study."

10 of 70 comments (clear)

  1. Depends on "who's" online polygraph it is by mykepredko · · Score: 3, Insightful

    If this app was put online labeled as "Fred's AMAZING online truth teller" with the usual ads for bikinis, penis enlargement, crockery, the latest Chevy, I don't think you have anything to worry about in terms of it causing problems.

    If it's part of the Google home page or comes up automatically when submitting documents to the IRS, I think there is a great deal of concern regarding whether or not people believe the results are accurate.

  2. Machine Learning is going to do rocket science! by Hillie · · Score: 2

    But it can't even stop auto correct from sucking!

    --
    - Alex
  3. Likely closer to sarcasm detector by bugnuts · · Score: 4, Funny

    When it can determine its own press release is a lie, then I'll believe it.

  4. All Machine Learning systems have an error rate by sfcat · · Score: 3, Insightful

    All ML algorithms have an error rate. Its baked into the design. ML researchers talk about error rate all the time. There is even a term, 'irreducible error' in ML that refers to data points that can never be classified correctly by a specific algorithm. Its a mistake to completely trust what a computer database tells you because the wrong data could have been input or bugs could have changed that data in a weird way. Its all those risks plus the error that comes from the ML algorithm. The way to get around this is to have multiple algorithms "vote" but even then there is still an error rate. The error rate can be double digit % or lower than 1% but its always there. And all of this is on top of the risk of bad data just like a DB gives you. Garbage in/garbage out is a real principle. Trusting this stuff is tricky but the bar isn't perfection. Its better than a skilled human. And since I don't really trust a "skilled human" in lie detection, why on earth would I trust a ML algorithm that at best is only marginally better than that and could be far worse.

    --
    "Those that start by burning books, will end by burning men."
    1. Re:All Machine Learning systems have an error rate by DamnRogue · · Score: 2

      Also, most ML algorithms of this type produce a continuous score and not a binary Yes/No classification. Human users/customers provide a score cutoff that gives an acceptable confusion matrix for their use case.

      Alternatively stated, the machine does not say "Bob is lying", rather, "I think Bob is lying with X confidence".

    2. Re:All Machine Learning systems have an error rate by sfcat · · Score: 2

      Also, most ML algorithms of this type produce a continuous score and not a binary Yes/No classification. Human users/customers provide a score cutoff that gives an acceptable confusion matrix for their use case.

      Alternatively stated, the machine does not say "Bob is lying", rather, "I think Bob is lying with X confidence".

      You are confusing Regression with Classification. Classification produces a yes/no, choice A/B/C type answer. Regression produces a number or set of numbers often in a given range. You can turn a Regression system into a classifier with a simple cutoff but not vis-versa. Its common that ML algorithm implementions come in a Classification and Regression flavors. Also, getting a confidence interval out of a ML algorithm is possible but really difficult and of potentially questionable use. Its more honest to just list the overall error rate of the algorithm next to the prediction.

      --
      "Those that start by burning books, will end by burning men."
  5. I'm sure Kirk and Harry Mudd can deal with this .. by fahrbot-bot · · Score: 2

    Captain Kirk: Everything Harry tells you is a lie. Remember that. Everything Harry tells you is a lie.
    Harry Mudd: Now listen to this carefully, Norman. I am... lying.

    --
    It must have been something you assimilated. . . .
  6. It will be (ab)used by wbr1 · · Score: 2
    This 'AI' and others of it's ilk will be jumped on by law enforcement and government. They do not care if it is wrong. Just like existing polygraphs, it will be used to psychologically bully people and fool juror/the populace while having no basis in real science.

    With the current trend towards anti-intellectualism we have now, this will only get worse, not better.

    Read some of the info here about 'lie detection'. https://antipolygraph.org/

    I have some intimate experience with polygraphs. As a convicted sex offender, I have had to submit to them as part of a treatment regimen. I have passed polygraphs I lied on, and failed them while telling the truth. The judgement lies in the examiners subjective whims, not anything objective.

    --
    Silence is a state of mime.
  7. LoL by meerling · · Score: 2

    As nobody has actually built a "lie detector" that is significantly more effective than random chance, and yes that includes the polygraph, those "researchers" are fooling themselves.
    Even the inventor of the polygraph agrees that it's just b.s.

    Are we sure these people aren't actually from North Korea?
    You know, the place where "researchers" have claimed to have found a Magical Unicorn Cave, and have perfected human cloning, and so many other absurd claims.

  8. Let's feed this thing the bible and quran by HaroldJ.Wolfe · · Score: 2

    I'm dying to see what it says. It will be fooled like 85% of the population