Someone tosses a coin ten times; it comes up heads every time. What's the probability it comes up heads on the next toss? (Pretty darn high—part of @nntaleb's work is unprogramming you from your high-school rules of thumb.) Now consider the (related) Gambler's fallacy...

In this case, it's a theory about compensation: the worse one's luck is, the more likely it is to see a reversal. On the surface, it's irrational. The more bad luck you have, the more you accumulate evidence that the system is rigged.
But there's also an anthropic component. If the luck is bad enough, it starts to become inconsistent with your survival. You've accumulated evidence for correlations in the environment, but these correlations (may be) inconsistent with (people like you) being in this environment.
An example. You're in a city where everyone takes public transport. You encounter a string of bad delays. It's reasonable to conclude they'll end—otherwise people wouldn't take public transport. It's unlikely that you happened to show up right when the network collapses.
Of course, that's a bad heuristic in a casino, which relies on a constant influx of losers. But in other environments, particularly with persistent populations and no evidence for sudden changes in the underlying laws, it makes sense.
Another example: the three-card monte scam in a big city. You meet some guys on the corner, who convince you to go in on the game. You win, a few times. The more you win, the more you ought to be convinced that your luck will turn. Otherwise, how are these guys there?
(In this case, the anthropic reasoning concerns the scamsters—it's unlikely that you showed up right when their operation starts to fall apart.)
The general principle, which again is due to @nntaleb, is a new kind of failure. The "IYI", intellectual-yet-idiot. IMO, this is driven by standardized testing—we started to promote people on the basis of their ability to internalize fake-but-difficult-to-master rules...
In a previous cycle, the British ran their empire by fast-tracking twelve year olds who could master Latin grammar. The ambiguities of interpretation make this a much better idea than the SAT version, where one learns more abstract "grammars"—e.g., integration by parts.
Everything can be degraded, of course. When I give CMU students the coin-toss problem, it's usually unfamiliar enough that they're thrown back on a more complex, and life-integrated, form of reasoning. But ask that question enough, and tutors will arise to teach the solution...
...which negates the original value of the puzzle. (BTW, nearly all the students "get it", which bodes well for our future engineers.)
A final thought on this, before I get back to my real work. If you pose this kind of problem as a teacher, there's a second level to what's going on: your students are also modeling you! (and your class.)
i.e., they're asking themselves—is this a class where we're all living in la-la land, or is there some substance here, some connection to our own lived experience?
So, yes, I'm proud that most of my students get it. :)
This is lovely—yes! "I can't be the only idiot" summarizes why we keep waiting for the train with rising hope. https://t.co/s3d4aFg7Tv
You might also connect it to the bulk-vs-long-tail. "I'm not the only idiot" is true when there are repeated tests of the system of similar magnitude.
OK, truly one last thought. A scam is more likely to succeed if you're doing something new, but can convince people you've always been around, that this is "normal". Certainly psychologically obvious, but it's fun to look at it from the point of view of rational analysis.
(In the case where the scam operates by inducing the Concorde/sunk-cost fallacy—slowly extracting money from the person, who continues to believe in a final payoff.)

More from Simon DeDeo

"I lied about my basic beliefs in order to keep a prestigious job. Now that it will be zero-cost to me, I have a few things to say."


We know that elite institutions like the one Flier was in (partial) charge of rely on irrelevant status markers like private school education, whiteness, legacy, and ability to charm an old white guy at an interview.

Harvard's discriminatory policies are becoming increasingly well known, across the political spectrum (see, e.g., the recent lawsuit on discrimination against East Asian applications.)

It's refreshing to hear a senior administrator admits to personally opposing policies that attempt to remedy these basic flaws. These are flaws that harm his institution's ability to do cutting-edge research and to serve the public.

Harvard is being eclipsed by institutions that have different ideas about how to run a 21st Century institution. Stanford, for one; the UC system; the "public Ivys".

More from Crypto

You may be wondering why @bristoliver rather cryptically RT’d a chart that I posted last night. The answer is not just that he loves quadratic fits on log axes, but that this chart may –and I stress may– hint at a vaccine effect amongst the over 80s THREAD


WARNING: this is a long thread, and it’s a bit of a roller-coaster. We find some apparently strong patterns in the data, and then start to unpick them a bit. So if you start getting excited half way through you might find you’re less excited at the end. But we’ll see…

First we first have to go back a bit. @bristoliver posted a thread a few days ago explaining why, with a constant vaccination rate, a log plot of cases should show a quadratic form. In other words, it should fit an equation like: a + b.x + c.x^2

I meant to link in the model thread there - here it is


the quadratic coefficient – the ‘c’ in that equation – gives an estimate of the % of the population who are being newly protected by the vaccine each day. Please note ‘protected by the vaccine’, not ‘vaccinated’ – as we don't expect 100% protection after the first dose

You May Also Like