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Comment author: Jiro 03 June 2017 09:13:43PM 2 points [-]

There's a reason we have a "beware fictional evidence" article. Perhaps the two tribes who think they are ruled by a powerful empire don't go bankrupt buying weapons, but the belief that they are ruled by a powerful empire causes them to do things that are so bad for them that going bankrupt buying weapons is a better deal.

Comment author: dspeyer 04 June 2017 09:43:55PM 2 points [-]

The idea of rationalist seder is to -- carefully! -- use the effect described in "beware fictional evidence" to promote ideas to our awareness.

We know that "the obviously better thing wouldn't be a Nash equilibrium" traps exist, but we have trouble seeing them, and keep seeing malice and power where there is only desperation. We know that stories can give structure to societies (or, at least, we do if we've read Haidt), but we have trouble seeing it, instead seeing madness and gullibility. We know social structures have both costs and benefits which are difficult to weigh against each other, but tend to see only the side that is effecting us right now.

So I wrote this story, this obviously not true story, stripped to its barest bones, so that it could stick in our heads. So that when we should be noticing the things from the preceding paragraph, a spark of recognition fires in our brains and we generate the hypothesis. Once the hypothesis is generated, we can evaluate it with all the tools at our disposal, and this story will (hopefully) get out of the way.

Comment author: dspeyer 04 June 2017 09:29:40PM *  2 points [-]

Two small notes for those who aren't immersed in Judaism:

The "almost has been said" refers to the saying:

Keep two truths in your pocket and take them out according to the need of the moment. Let one be “For my sake the world was created.” And the other: “I am dust and ashes.”

credited to Rabbi Simcha Bunam, a leader of the chassidic movement in the early 19th century. He said, rather than wrote, this, so the exact phrasing may have gotten cleaned up by successive quoters (of which there have been many).

As for the rhythm of dayenu and lo dayenu, that's in the traditional melody (which is itself of uncertain origin, but probably a few centuries old at least). Traditionally, the extra beats are filled in by singing "day-dayenu, day-dayenu, day-dayenu, dayenu, dayenu". Almost as if the melody wanted "lo"s in front of half of the dayenus...

Comment author: dspeyer 09 January 2016 07:41:33PM 1 point [-]

I can't avoid all my problems by drawing squirrels, but when I can, I do.

--Randall Munrow

Comment author: dspeyer 05 January 2016 08:17:15AM 15 points [-]

There's a sort of Gresham's Law of conversations. If a conversation reaches a certain level of incivility, the more thoughtful people start to leave.

--Paul Graham

Comment author: gwern 02 December 2015 08:19:13PM 0 points [-]

but timing isn't one of them.

Hm? What Pisani is pointing out here is that of the 3 major causal patterns that a cross-sectional correlation can reflect, A->B, B->A and A<-C->B, a longitudinal correlation in which observations of A are followed by observations of B, will let you rule out 1 of the 3 patterns (B->A), reverse causation, which leaves either the hypothesized direct causation or confounding. This is much better evidence than just the cross-sectional approach, although I think confounding is much more likely in general so the boost is not as big as the trichotomy makes it sound.

Comment author: dspeyer 27 December 2015 08:28:23AM 1 point [-]

Reverse causation is not ruled out because diagnosis can be delayed.

It seems entirely plausible to me that it takes several months of worsening depression symptoms (during which time sex drive is effected) before a patient sees a psychiatrist.

I suppose it's ruled out if we separate "depression" and "diagnosed with depression" into separate nodes, but that doesn't rule out anything interesting.

Comment author: dspeyer 03 December 2015 05:35:44AM *  5 points [-]

I think the common thread in a lot of these [horrible] relationships is people who have managed to go through their entire lives without realizing that “Person did Thing, which caused me to be upset” is not the same thing as “Person did something wrong”, much less “I have a right to forbid Person from ever doing Thing again”.

--Ozymandias (most of the post is unrelated)

Comment author: Jiro 04 November 2015 07:32:45PM 4 points [-]

I think that the lifespan that humans can live to if they wish, given current medical and scientific knowledge, is too low.

Comment author: dspeyer 04 November 2015 11:05:14PM 5 points [-]

I agree.

The model I use to derive that involves looking at lots of dying people who don't want to die. If we had lots of people lying around saying "I wish I could die; why can't I die?" that same model would conclude the lifespan is too long.

Comment author: elharo 02 November 2015 12:45:14PM 2 points [-]

I picked up the folders for the two courses required of every student at the school. Statistics and epidemiology. Epi—what?

In the first lecture, we ‘reviewed’ all the major study types. For example, in the case-control study you find a group of people with a disease, and then look for people who are much the same but without the disease. You compare the two groups to see if they have different risks. It’s a relatively cheap method, but it doesn’t tell you much about the order in which things happen. I can’t remember all the examples used in the lecture, but let’s say you want to look at causes of depression in women. You start with 600 depressed women, find another 600 who match them in age, ethnicity and educational status, and then ask them all about their lives. Let’s say you find out that women who are depressed are six times more likely not to have had sex in the last year as women who are cheerful. That means if you’re not having sex you get depressed, right? But hang on, couldn’t it be that women who are moping around looking miserable don’t get laid much?

Perhaps you’d be better off with a cohort study. You start off with several thousand women who are perfectly happy. Then you follow them over time, recording their behaviours, and see which of them get depressed. If you find that women who have sex are less likely to become depressed than women who aren’t getting any, it suggests it is the lack of sex that causes the depression, not the depression which stops you getting laid. You can throw out the ‘misery guts’ theory and recommend more good sex as an intervention to promote mental health.

-- Elizabeth Pisani, The Wisdom of Whores, p. 16

Comment author: dspeyer 04 November 2015 10:00:00AM 5 points [-]

Chronology is evidence of causality, but it's weak evidence. In this case, there are (at least) two problems. First, there could be some other factor (disruption of social network? increase in pro-inflamatory microbiota?) which causes both, but the sex is caused faster. Alternatively, it could be that depression causes low sex drive, but that kicks in immediately whereas it takes months to get a depression diagnosis.

There are good ways to determine causality from observational data, but timing isn't one of them.

Comment author: dspeyer 04 November 2015 09:45:53AM 10 points [-]

Don't trust any model that implies X is too low unless it's also capable of detecting when X would be too high


Comment author: dspeyer 04 October 2015 08:02:03PM 4 points [-]

The smug mask of virtue triumphant could be almost as horrible as the face of wickedness revealed. Almost as horrible, but not quite.

-- Granny Weatherwax. Carpe Jugulum, Terry Pratchett

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