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Heuristics that almost always work

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Re: Heuristics that almost always work

#131

Post by pards »

The doctor rings true. I had 3 separate doctors on 3 separate occasions diagnose my 21 month old son with an ear infection, instead of the plum-sized malignant brain tumour that it was.

From their point of view, pediatric brain tumours are very rare and ear infections are common.

Their 99% heuristic almost killed him.

That was 2010. He survived and is now a vibrant 13 year old, but only because of one curious intern/fellow at the children's hospital ER that decided to order a CT to rule out the remote possibility. Her diligence got him admitted and into surgery within a day.

Re: Heuristics that almost always work

#132

Post by XorNot »

scoofy wrote: post #40
rthomas6 wrote: post #16

This is what Nassim Nicholas Taleb has been writing books about. He calls them black swan events, because if you took a sample of 1000 swans, chances are you'd conclude that all swans are white, but it just isn't so. People tend to round down the probability of very rare events to zero, even when the upside of them is small and the downside is catastrophically bad. Examples: the 2008 housing crisis, Fukushima, and ou…

These are NOT black swan events. These are probably all White Swan events (possibly grey swan events, but i'd have to review stuff that i don't want to right now). E.g. High certainty, just low predictability. From the book, when you know the statistics of a rare event, and then the even occurs, it's absolutely not a black swan event. For an event to be a Black Swan event, you literally need to have no possibly for t…

We know pandemics happen but we have no idea which viruses will become pandemic viruses - until one emerges, we're generally confident that there is not an imminent pandemic.

Re: Heuristics that almost always work

#134

Post by nefitty »

pessimizer wrote: post #114
aaronblohowiak wrote: post #100

Earlier quoted context omitted.

but the risk is independent. so once you do the N+1 time safely, you are back to N and your next time is _also_ just an N+1.

Continuing to do something regularly doesn't ever mean you're just going to do it once more.

Psychologically, behaving in a certain way makes it more likely that you'll behave in the same way in the future. That's an integral idea underpinning justice systems.

Re: Heuristics that almost always work

#135

Post by moralestapia »

robbedpeter wrote: post #65
PaulHoule wrote: post #6

You'd do a lot better with one strong example rather than seven weak examples. For instance, if you are interested in Bayes Theorem like a lot of rationalists say they are, you could talk about the medical test which is 99.99% accurate but for which 90% of the positives are false positives.

Drug testing is a good example for most people to understand why Bayesian thinking is relevant. https://www.mun.ca/biology/scarr/4250_Bayes_Theorem.html Imagine that a driver gets hit by accident. He's tested as part of company policy, and tests positive. He gets fired, even though the test only really tells us there's a 33.2% chance he was actually using the drug. Real world drug tests are a lot worse than 1% false…

>All that matters is if an officer feels like fucking up your day.

This is what most people don't seem to get. Devices like the ADE 651 or the GT200 were bought by the thousands by law enforcement agencies worldwide, not because they were stupid, but instead, so they could have another "data point" against you that they can use at their discretion.

"Sorry, this dot blinked three times so I'm gonna have to detain you: It's standard procedure, I'm only doing my job."

Re: Heuristics that almost always work

#136

Post by twobitshifter »

aaronblohowiak wrote: post #100
HPsquared wrote: post #82

Earlier quoted context omitted.

The "slippery slope" principle applies here though: N+1 enables N+2, which enables N+3 and so on.

but the risk is independent. so once you do the N+1 time safely, you are back to N and your next time is _also_ just an N+1.

True but it would be incorrect to assume that you can safely keep basejumping every day in a year, just because you haven’t died in the last 50 days. Eventually the stats say you will be 87% likely to have an accident when you consider your choice at the beginning of the year. It might be day 20 or day 300, but you won’t know what case you end up in. The chance of your next jump being your last is always the same, but that doesn’t decrease the risk of repeated trials.

Re: Heuristics that almost always work

#137

Post by montebicyclelo »

HWR_14 wrote: post #61
kbuchanan wrote: post #35

Earlier quoted context omitted.

It's a great example. This is the very reason I have scaled back the amount of time I rock climb as I've gotten older -- not because any individual outing is dangerous, but there's an element of Russian roulette wherein the mere act of doing it more often dramatically changes the risk.

> the mere act of doing it more often dramatically changes the risk. Kind of. However, you already know that the first N outings didn't have a disaster. So those should be discarded from your analysis. Doing it N times more has a lot of risk, doing it the N+1th time has barely any.

The parent comment talks about scaling back the amount of rock climbing they do in order to reduce risk.. And now you are saying that they should go one more time, because a single climb is low risk?

Re: Heuristics that almost always work

#138

Post by [deleted] »

pessimizer wrote: post #108
HWR_14 wrote: post #61

Earlier quoted context omitted.

> the mere act of doing it more often dramatically changes the risk. Kind of. However, you already know that the first N outings didn't have a disaster. So those should be discarded from your analysis. Doing it N times more has a lot of risk, doing it the N+1th time has barely any.

If you'll die if a roll of three dice comes up sixes, you're not really in a lot of danger. If you do it every day, you have about 15 months to live.

[deleted]

Re: Heuristics that almost always work

#139

Post by travisporter »

> But then you consult a bunch of experts, who all claim they have additional evidence that the thing won’t happen, and you raise your probability to 99.999%

I lose the line of reasoning here - 99.9 to 99.999 doesn't happen if you don't have new evidence, so why would you raise your probability? or maybe i'm being too literal?

Re: Heuristics that almost always work

#140

Post by 323 »

inglor_cz wrote: post #30

This story reminded me of a story written by a Czech biologist who studied animals in Papua-New Guinea and went to a hunt with a group of local tribesmen. The dusk was approaching, they were still in the forest and he proposed that they could sleep under a tree. The hunters were adamant in their refusal: no, this is dangerous, a tree might fall on you in your sleep and kill you . He relented, but silently considered…

Taleb has a similar example: the difference between playing Russian roulette once for a chance of winning $10 million, versus playing it repeatedly.
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