3 HN users recommended this explainer3 months2015–2023score 3
Years with an HN recommendation, 2007–2026
Recommended as a clear demonstration of confirmation bias and the value of trying to break your own hypothesis.
A Veritasium video that runs the 2-4-8 rule-guessing puzzle on people to show how they test only examples that confirm their hypothesis. It uses this to illustrate confirmation bias and falsification.
“I would suggest this video by Veritasium, which also touches on this, at a very fundamental level” (HN, 2021)
Veritasium, a pretty interesting youtube channel, posted a video on this experiment a while back. I found the discussion afterwards to be more thought-provoking than this article. [this video]
Veritasium video on this experiment, with thought-provoking discussion.
Experimental science is all based around ruling out the null hypothesis. For that it needs to be falsifiable . The hypothesis 'the dog can differentiate between A and B' is very hard to falsify. Because the dog could differentiate, but choose to not act. You would need a fairly complete understanding of the dogs mental workings, and scanners to study them. On the other hand, 'the dog can't differentiate between A and B' is much easier to falsify. If you repeat an experiment a sufficient amount of times and the dog consistently has different behavior between A and B, you can rule this null hypothesis out. That is the real reason we always 'assume the worst'. Because 'assume the worst' is the easiest to scientifically rule out. EDIT: I would suggest this video by Veritasium, which also touches on this, at a very fundamental level: [this video] .
Fundamental look at falsification and confirmation bias.
Veritasium has a great video[1] about people’s cognitive bias towards using examples that prove their mental model, rather than using examples that disprove their mental model. But if you want to actually confirm you have accurate understanding of something, testing examples that don't fit your metal model is the workable methodology (i.e. use a null hypothesis). Testing examples that do match your mental model only proves your model partially matches the actual model, but it does very little to actually identify misunderstandings, or improve your understanding. [1] [this video]
Why people test examples that confirm their mental model.
Derek Muller of Veritasium has done this test over a year ago on people in one of his videos: [this video] I've given the test to various people since then and never once came across someone who'd guess it right away, or within a short period of time. The breaking time came usually after a few minutes when they gave up and started throwing out random numbers that coincidentally did not meet the rule. Once you hit the first "No", it took a very short time to figure out the rule for almost everyone.
Veritasium runs the same rule-guessing test on people.
This is now the fourth time I've seen this exact rule. Another example: [this video] It's probably not "fair" to say I got it in zero... but I did. :) Now that the NYT has done it, this puzzle has probably attained enough popularity now that you really ought to change it up a bit now if you're going to run it yourself. Granted, the space of hypotheses as simple as "increasing/decreasing" is pretty small, but your ability to fool people with the first sample run is almost unbounded, so that helps.
Very interesting! This reminds me of a Veritasium video I watched years ago, called “The most common cognitive bias” [1]. People don’t explore solution spaces as effectively as they think they do. [1] [this video]
Related: [this video] TL;DW: I have a rule and you need to figure it out. The rule relates to a sequence of three numbers. You can propose a sequence and I’ll tell you yes/no if it meets the rule. I’ll give you the first sequence to get you started: sequence: 2,4,8 passes: Yes
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