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Heuristics that almost always work

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Re: Heuristics that almost always work

#141

Post by klik99 »

the_af wrote: post #72

One interesting twist on the doctor example: we know she is almost always right that it's nothing, that it will all go away and that just two aspirins are ok. The article correctly points out that she will miss one or two cases where it was a terrible disease instead, and that her prescription of aspirin and to go away and rest will be misguided. However... doctors must do more than just cure you. They must also "do…

Good point - he assumes that false positives are always less costly than false negatives, but that may not be true in this example.

Re: Heuristics that almost always work

#142

Post by kqr »

wongarsu wrote: post #110
Fernicia wrote: post #79

Earlier quoted context omitted.

Isn't that called Pascal's Wager?

Which of course directly leads to Pascal's Mugging: I can simply say "I'm a god, give me $10000 or you will burn in hell for all eternity". Now if you follow Pascal's Wager or GP's logic you have to give me the money: I'm probably lying, but the potential downside is too great to risk upsetting me.

There's actually a rational explanation for that: humans don't care very much about burning in hell for all eternity, when it comes down to it.

There's actually a similar though experiment that might seem even more bizarre: I could tell you "give me $100 or I will kill you tomorrow" and you probably wouldn't give me the $100. That's because when it comes down to it, humans don't see the loss of their life as that big a deal as one might think. It's a big deal, of course, but in combination with the low likelihood, still not big enough to forgo the $100.

Re: Heuristics that almost always work

#143

Post by srcreigh »

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.

Under this assumption, by the principal of mathematical induction, you can easily do it K more times for any K without taking on barely any risk at each step of the way.

Re: Heuristics that almost always work

#144

Post by jrochkind1 »

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.

If you've already done it for 12 months without it happening though, the next 3 months are no more dangerous for you than for someone starting from scratch.

Re: Heuristics that almost always work

#145

Post by alexfrydl »

the_af wrote: post #72

One interesting twist on the doctor example: we know she is almost always right that it's nothing, that it will all go away and that just two aspirins are ok. The article correctly points out that she will miss one or two cases where it was a terrible disease instead, and that her prescription of aspirin and to go away and rest will be misguided. However... doctors must do more than just cure you. They must also "do…

The problem is that people are not statistics. It may sound reasonable on the surface to say that this heuristic minimizes harm on average because she doesn't perform unnecessary interventions on the 99.9%. However, there are still actual human beings in the 0.1% who are harmed. What you're really saying is that if a group of people is small enough, it's fair for them to suffer preventable harm if preventing it would expose the larger group of people to risk.

I'm not going to argue about whether that is true or not, because I think that clearly depends on many factors and may be unanswerable. But as a member of a minority group who is often denied health care, it is often denied for this very reason. If the wrong person is prescribed this treatment, it is harmful. I'm just saying that when you're in the 0.1%, it can be difficult to accept the idea that you have to sacrifice yourself because someone in the 99.9% might be at risk otherwise.

Re: Heuristics that almost always work

#146

Post by s1artibartfast »

woodruffw wrote: post #128
ravi-delia wrote: post #126

Earlier quoted context omitted.

Where are you seeing the author suggest most people in the described jobs could actually be replaced by rocks?

> Where are you seeing the author suggest most people in the described jobs could actually be replaced by rocks? I really think it's harder to get more literal than this: > He could be losslessly replaced by a rock with the words “THERE ARE NO ROBBERS” on it.

I think the point is that the person who inappropriately uses a heuristic instead of doing their job, is in fact, not doing their job.

Re: Heuristics that almost always work

#147

Post by pessimizer »

the_af wrote: post #72

One interesting twist on the doctor example: we know she is almost always right that it's nothing, that it will all go away and that just two aspirins are ok. The article correctly points out that she will miss one or two cases where it was a terrible disease instead, and that her prescription of aspirin and to go away and rest will be misguided. However... doctors must do more than just cure you. They must also "do…

I think this is a little different - it's "doing the math." The best contemporary example I think is early/frequent mammograms/checks for prostate cancer. If we check how often what we can detect will develop into a threat to health, and compare that to the consequences of treatment at that early stage, we may determine that under some conditions the results of our diagnostics kill more people than the disease would, and therefore we shouldn't do them.

That's different than not treating people at all - even if it's not treating people at all, because the reason you're not doing it is because your diagnostics and treatments are inadequate.

Re: Heuristics that almost always work

#148

Post by bentcorner »

AlexCoventry wrote: post #57
jppope wrote: post #2

One of the amazing subtleties in this article... if you're a fast reader you'll stop paying attention to the stories as they go through... kind of amazing that this article is layered like that.

I developed a rock inside my head, and the rock said "THESE PEOPLE WILL ALL FALL AFOUL OF RIGID DICTATES WRITTEN ON A ROCK."

Second-to-last story should have been about a person that did not fall afoul of the rock. Then in the last segment ask the reader if they developed their own rock.

Re: Heuristics that almost always work

#149

Post by 323 »

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.

This is called the Turkey fallacy: the turkey was feed by humans for 1000 days, and after each feed event he updated his belief that humans care for him until it's now almost a statistical certainty.

Re: Heuristics that almost always work

#150

Post by joe_the_user »

PaulHoule wrote: post #7
bryanrasmussen wrote: post #4

>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 except for the value of having a security guard visible so that 99% of the robbers who might conceivably want to rob a Pillow Mart decide to go rob Quilting Heaven down the road instead.

Instead of a rock you just need an inflatable security guard. What's frightening about all this is that this article has gotten 15 upvotes despite 100% of the comments so far being about what a pointless article this is.

I didn't unvote it and I think each of the example is missing subtle aspects.

But I think it's interesting enough to discuss. The main thing is that are a whole lot of human activities where one can imagine completely rote activity could replace thinking. But in all of these, a deeper look shows to subtle factors actually require a human being to be present.

It's a bit like self-driving cars. 90% of driving is really easy to get working. 99% is moderately hard. 100% looks like it won't arrive for quite a while.

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