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Heuristics that almost always work

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351–360 of 541 posts

Re: Heuristics that almost always work

#351

Earlier quoted context omitted.

The risks are highest when learners are at a beginner to intermediate stage. They know the basics, and have gained some confidence, but don't know enough to get themselves out of trouble. This is called Stage 1 in the Gordon Model of learning: unconscious incompetence.

While this is true, in the context of alpine climbing where I first heard this statement, the bold alpinists who die young are very much not beginner-intermediates. I've interpreted this differently than just the "Bathtub Curve"[1] applied to dangerous pursuits. Rather, there is a certain amount of objective risk in alpine environments, and the more time you put yourself in that environment, especially in locations y…

Another good allegory is that, in the US Air Force, the flight crews considered most dangerous are those with the highest collective rank. Sure, the young crews are learning but the old ones still think they know it all and have often forgotten critical details.

Re: Heuristics that almost always work

#353

I read them as sloppy caricatures that provide little value to the conversation. Let's take the security guard: "The only problem is: he now provides literally no value. He’s excluded by fiat the possibility of ever being useful in any way. He could be losslessly replaced by a rock with the words “THERE ARE NO ROBBERS” on it." That is blatantly not true, the guard provide value since the wanna-be robbers don't know w…

You have a very weird idea of what security guards do. They don't sit in front of the entrance all night, scaring off would-be robbers. They are inside the building, in their booth, probably looking over some monitors. They do not provide a deterrent, they just call the cops if something does happen. Robbers have no clue if they are there or not. The heuristic works fine.

Re: Heuristics that almost always work

#354

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…

Australian here. Never ever ever park, and especially never ever ever ever camp, under gumtrees.

They can and do drop large limbs at any time without warning.

There are gum trees in PNG.

Re: Heuristics that almost always work

#355
post #199

Earlier quoted context omitted.

Which is the rub, right? How can a non-expert reasonably come to a conclusion of whether or not an expert's prediction is baseless or is actually solid/insightful?

By getting a second or third opinion, no?

Not really. Get three opinions from professionals giving the default answer and you have three default answers. Because it’s non-competitive it doesn’t even require coordination. Get three home appraisals in 2007 and they’re all coming in at the offer. They don’t have to know each other, they’re just aligned with the same individual incentives.

Re: Heuristics that almost always work

#356
Wow, the doctor story really hits close to home for me.

My mother was fat. She was feeling especially tired for several months. She went to her doctor. The doctor was historically kind of embarrassed that my mother was fat, told her to lose weight, and didn't palpate her swollen belly.

My mother went to the dentist. The dentist had known my mother for years, and palpated her belly. She sent her immediately to the emergency room.

Happily, my mother survived metastatic lymphoma after the removal of the 9" tumor in her belly, a heavy dose of chemo, and an autologous stem cell transplant. Modern cancer treatment is really impressive!

My mom has been in remission for over a decade, but I'm still really mad at her general practitioner.

Re: Heuristics that almost always work

#357
post #267
post #179

Earlier quoted context omitted.

Reminds me of the fact that on overage, one out of every hundred places you know will be experiencing a once-in-a-hundred-years event. When you hear once-in-a-hundred-year event, it makes it sound quite rare. One might look around and say (for example, in relation to climate) "why are so many of these happening?" But it is unsurprising statistically. If you know just a thousand distinct geographic places, about 10 of…

There's something intuitively misleading here, though I'm not sure what it is. I am looking at 100 square inches of floor right now and nothing unusual is happening in any of them.

It has to do with how correlated conditions are in your 100 places. Conditions on one square inch of your floor are very highly correlated with conditions on another square inch of your floor, so they wouldn't be able to experience a 1-in-100 event independently -- if one part of your floor did something unusual, the other parts probably would too. Conditions on the floor the next room over are also pretty highly correlated, but not quite as high (maybe a fissure could open up and swallow the kitchen, but not your office). So in order for the parent comment to be true, their thousand distinct geographic places would need to be statistically independent from each other.

Of course in practice, it's quite hard to know whether conditions in one location are independent from another, or whether there's some degree of correlation or an underlying causal factor. This is why we have climate scientists.

Re: Heuristics that almost always work

#358

I read them as sloppy caricatures that provide little value to the conversation. Let's take the security guard: "The only problem is: he now provides literally no value. He’s excluded by fiat the possibility of ever being useful in any way. He could be losslessly replaced by a rock with the words “THERE ARE NO ROBBERS” on it." That is blatantly not true, the guard provide value since the wanna-be robbers don't know w…

You have a very weird idea of what security guards do. They don't sit in front of the entrance all night, scaring off would-be robbers. They are inside the building, in their booth, probably looking over some monitors. They do not provide a deterrent, they just call the cops if something does happen. Robbers have no clue if they are there or not. The heuristic works fine.

There are plenty of places with visible security guards.

Re: Heuristics that almost always work

#359
post #291

Earlier quoted context omitted.

I interpret the linked article different. Can you elaborate? For example (from the summary): =============================== "CONCLUSION. Radiation exposure from the use of CT in the evaluation and management of severe traumatic brain injury causes negligible increases in lifetime attributable risk of cancer and cancer-related mortality. Treating physicians should not allow the concern for future risk of radiation-in…

Excess Cancer Mortality per 100,000 individuals exposed to 100mSv is ~1000 in the 1 year-old male cohort. A single scan is ~3mSv, which makes the mortality ~30 per 100k, or 1 in ~3333, assuming the linear no-threshold model[1]. When someone comes to the ER with a traumatic brain injury, a CT scan is the standard practice because they are at a high risk of dying and presumably the scan is important for reducing the ri…

I'm so glad you mentioned the linear no-threshold model.

Do you believe in it? I don't, particularly at the single digit mSv level.

Re: Heuristics that almost always work

#360

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…

Even if you're going to do it only once it is still very dangerous compared to the risks we normally take. 1:5000 is 200 micromorts, about 25x as dangerous as hang gliding! [1]

[1] https://en.wikipedia.org/wiki/Micromort

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