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Don’t believe people who say they can look at your face and tell that you’re lying.

Kevin Lewis points us to this article, Lessons From Pinocchio: Cues to Deception May Be Highly Exaggerated, by Timothy Luke, which begins:

Deception researchers widely acknowledge that cues to deception—observable behaviors that may differ between truthful and deceptive messages—tend to be weak. Nevertheless, several deception cues have been reported with unusually large effect sizes, and some researchers have advocated the use of such cues as tools for detecting deceit and assessing credibility in practical contexts. By examining data from empirical deception-cue research and using a series of Monte Carlo simulations, I demonstrate that many estimated effect sizes of deception cues may be greatly inflated by publication bias, small numbers of estimates, and low power. Indeed, simulations indicate the informational value of the present deception literature is quite low, such that it is not possible to determine whether any given effect is real or a false positive.

Indeed, I’ve always been suspicious of people who claim to be able to detect lies by looking at people’s faces. Valuable information can be obtained from facial expressions, that’s for sure, but detecting lies is tough; it can just be a way for people to exercise their prejudices.

That said, when I was a kid, whenever my sister and I had a dispute, she always told the truth and I was always lying, and my parents believed her every time. It was soooo unfair: they’d believe her, even when there was no direct evidence contradicting whatever story I happened to be spinning.


  1. Michael Bailey says:

    Were your parents paying attention to base rates?

  2. Elvis says:

    So adorable! Love this.

  3. Terry says:

    So deception research is deceptive.

    The irony is strong with this one.

  4. jim says:

    One way to tell when people are lying is if what they’re saying is bullshit.

    Seriously though wouldn’t it be more interesting to study the people who are dupes for liars? I mean, the people who take one look at Wansink’s soup bowls and go “oh, OK”?

    • Andrew says:


      The usual explanation I’ve heard for why we’re often easily fooled is that this is the result of a long iterated game, played out over eons of evolution, by which the most effective strategy for speakers is to mostly tell the truth, and the most effective strategy for listeners is to mostly believe people. Short term there are benefits to lying, but long term it is costly to lie and to have to figure out whether someone is telling the truth. The strategy of default belief is, on net, a good one in a society of mostly-truth-tellers, as the costs of occasionally being fooled are outweighed by the gains of more direct coordination. In short, truth-telling and belief resolves the coordination problem. But then in such a society there is, by necessity, room for Wansinks to lie with impunity and to get away with it for years.

      • jim says:

        Andrew, thanks! I hadn’t thought it through that far, that makes a lot of sense.

        You know it’s interesting re: wansink because I think the first few times I saw the infamous refilling bowl nothing registered for me either. But when I watched wansink’s talk the lack of actual data became startling and the bowl suddenly looked ridiculously fake. So it’s interesting how perceptions change.

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