Log in

No account? Create an account
I don't believe in "believing in" things - Jackdaws love my big sphinx of quartz [entries|archive|friends|userinfo]

[ userinfo | livejournal userinfo ]
[ archive | journal archive ]

I don't believe in "believing in" things [Dec. 31st, 2012|05:50 pm]

[Epistemic Status | Polemical format. If I wanted to be scrupulously fair, I could admit that processing the statistics a different way - for example taking medians rather than means - makes things less *perfect*, though I still think the numbers support my point. Also, my reasons behind my answer to the final question are more complex than I admit, and may include "being dumb".]

RationalWiki has a discussion thread up: "Does Yvain believe in cryonics?" ("Yvain" is one of my Internet handles). Since no one bothered to ask me or even tell me about the thread I feel okay making anyone who wants the answer first read through a lengthy but important deconstruction of the question.

Many LWers are signed up for or considering cryonics, or think it's a good idea. Almost no one in the general population is signed up for or considering cryonics, and they mostly think it's stupid and crazy. This might lead some very silly people to think that reading Less Wrong convinces people to "believe in cryonics" more than the average member of the general population. This is absolutely wrong and I can prove it.

I'd like to be able to prove it by comparing LWers' degree of belief in cryonics with that of a matched control population. Unfortunately I don't have the data for that. I have great numbers on LWers' degree of belief - the Less Wrong Survey, which asked participants what percent chance they thought cryonics had of working, but I don't know of any survey on anyone else's belief in cryonics, let alone an identical question asked to a matched population.

But all is not lost! We can try to extract the data we want from the Less Wrong Survey (if you have a statistics package, you're welcome to download the data, check for yourself, and keep me honest). The trick will be to compare extreme newcomers - people who have just stumbled across the community and not been influenced by any of its ideas - to veterans who have been fully "indoctrinated". If Less Wrong convinces people to believe in cryonics, we should find that the first group has relatively low belief in cryonics, and the second group relatively high.

To represent the "low exposure to Less Wrong" population, I drew out of the survey results only those people who had been on the site less than a month and had 0 karma (karma is a measure of how much you contribute on Less Wrong). There were 47 of these people who had filled in cryonics information. To confirm that these people hadn't been influenced by Less Wrong much, I checked their exposures to the Sequences, the posts by Eliezer Yudkowsky that make up the core of the site. 64% of these low-exposure people had never read any of Eliezer's posts, and another 22% said they had read very few - less than a quarter of them. Only 14% of this population had read a quarter or more of Eliezer's posts.

Among this virgin population, no one was signed up for cryonics. Two people (4%) were in the process of trying to sign up. The mean probability given that cryonics could work was 15%

Now we set up their foil, the Less Wrong Veteran Group. These people have been in the community more than two years and have 1000 karma or above. 59 of this group had filled in cryonics information. Again to confirm that these people have been influenced by Less Wrong, I checked their Sequence exposure: over 70% of this group have read all of Eliezer's posts; only one of them had read less than 25%. There are a lot of these posts, so these are some serious site users.

Among this veteran population, 10 people - over a sixth of the total - were signed up for cryonics. When you add in the people who are in the process of trying to sign up, 53% - over half! - are would-be cryonauts. And the mean probability they give that cryonics could work is...12%.

So as people go from LW virgins to LW veterans, the probability that they are planning to get frozen increases by over thirteen times, but if you ask them whether cryonics will work, they are slightly but noticeably more skeptical. How could this be?

(dramatic question intended entirely for RationalWiki readers; this makes perfect sense for anyone from Less Wrong)

Less Wrong is a site that tries to teach people how to reason and make decisions. One of the first lessons it teaches is to think in probabilities. Let me give an example of this:

Consider a perfectly normal lottery with a jackpot of a million dollars and ten million tickets each of which costs $1. If you know how to do basic expected utility calculations it's very obvious that this lottery is a bad deal.

Now consider a second lottery where the lottery company makes some sort of horrible mistake. The jackpot is still a million dollars, but now there are only three tickets, each of which costs $1 and has a 33% chance of winning. If you know how to do basic expected utility calcuations it's very obvious that this lottery is a good deal. Even if you don't know the math, just eyeballing the chance to pay a dollar for a one in three chance of winning a million bucks seems like a good idea.

Now imagine you bought a ticket for the second lottery, and a friend - let's call her Rachel Nalwiki - comes up to you. "You bought a lottery ticket?!" she asks. "Do you really believe you'll win? I asked the lottery commissioner, and he said the odds of winning were only 33%! But you seem to believe you'll win anyway! How dumb can one person be?"

The flaw in Rachel's argument is that "believe you'll win" and "believe you'll lose" aren't really the right categories to use here. Since I know the probability of winning is 33%, if you asked me outright "Do you believe you will win the lottery", I would have to admit I do not - it's more likely that I'll lose than that I'll win. And yet I was perfectly justified to buy the ticket anyway.

Rachel retorts: "But everyone knows the lottery is a tax on people who are bad at math! Only stupid people play the lottery!" This is true. You definitely look stupid for playing, at least until the results come in. And there's a 2/3 chance you'll look stupid forever. But for a 1/3 shot at a million dollars, it's worth looking a little stupid.

Cryonics is much the same. Rachel tells the salesman: "Cryonics only has a 10% chance of success! That's less than 50%! That means it probably won't work! You are a bad person, to sell people this thing that probably won't work!"

You tell the salesman: "Wait, you mean I can buy a 10% shot at living forever for only $25 a month? That's less than I pay for car insurance! Where have you been my whole life?"

The difference between the newbie Less Wrongers who don't like cryonics and the veteran Less Wrongers who do like cryonics isn't that the veterans have a higher probability of it working. It's that they know what to do with probabilities once they have them, and they have a better estimate of the relative costs and benefits of looking stupid versus living forever.

To which Rachel might reasonably retort: "Well that just means that everyone, including the general population, has too high an estimate of cryonics. And it's only after people learn Less Wrong's techniques for thinking in probabilities that their ignorance has adverse consequences. You know what they say about a little learning being a dangerous thing..."

In fact, let's have that conversation:
Rachel: The general population is hopelessly biased in favor of cryonics. I am smarter than they are and I'm certain it won't work.

Scott: But we both know one hundred percent certainty is mathematically impossible. So exactly how sure are you that cryonics doesn't work, Rachel?

Rachel: Oh, at least ninety-nine percent certain.

Scott: And are you aware that when people say they're ninety-nine percent certain on a difficult question, they're wrong twenty to forty percent of the time?

Rachel: Uh, no?

Scott: It's a pretty universal problem. So unless you have personally studied techniques for estimating probability estimates and gone through some kind of laborious calibration training, I'm just going to mentally adjust every time you say "ninety-nine percent certain" on a difficult non-mathematical question to "approximately seventy percent certain".

Rachel: Um...

Scott: So, I hear you're only approximately seventy percent certain that cryonics doesn't work...

I guess if anyone from RationalWiki read all the way through here I might as well finally answer their original question of "whether I believe cryonics works".

I haven't really looked into it at all, so my default mode is to go with the opinions of smart people who have. I don't know of any neuroscientists who have given a precise numerical estimate, and even if they did I wouldn't expect them to know how to use probabilities and to avoid the "99% sure actually means 70% sure" problem. If some smart unbiased neuroscientists with calibration training have given some probability estimate on cryonics, I will happily accept whatever they say.

In the absence of that, I'll just go with that 12% number.

Am I signed up for cryonics? No, and I am not planning to. This isn't because I'm less crazy than the rest of Less Wrong, it's because I'm much, much crazier.

Page 1 of 4
<<[1] [2] [3] [4] >>
From: (Anonymous)
2013-01-01 04:42 am (UTC)
I'm just going to mentally adjust every time you say "ninety-nine percent certain" on a difficult non-mathematical question to "approximately seventy percent certain".

I am 99.9999994% (175 million to one odds) sure that if I buy a Powerball ticket, I won't win the jackpot. Should I update that to 30%?
(Reply) (Thread)
[User Picture]From: squid314
2013-01-01 05:11 am (UTC)
Things where you can get the correct answer by simple arithmetic (like calculating number of tickets vs. number of winners) is what I meant to exclude by "difficult non-mathematical questions".
(Reply) (Parent) (Thread)
(no subject) - (Anonymous) Expand
[User Picture]From: selenite
2013-01-01 04:51 am (UTC)
After I see reliable reports of someone getting thawed out or otherwise revived after cryosuspension I'll apply math to it. Otherwise it's just another variant on Pascal's Wager.
(Reply) (Thread)
[User Picture]From: gwern branwen
2013-01-01 05:17 am (UTC)
Refusing to think about it doesn't make risks or opportunity go away.
(Reply) (Parent) (Thread) (Expand)
(no subject) - (Anonymous) Expand
(no subject) - (Anonymous) Expand
[User Picture]From: gwern branwen
2013-01-01 05:42 am (UTC)
Well, that's pretty surprising. I would have predicted increasing belief in cryonics plus increasing likelihood of signing up. Just the latter surprises me. But the stats look quite different:

R> lw <- read.csv("2012.csv")
R> lw <- subset(lw, !is.na(as.numeric(lw$TimeinCommunity)))
R> lw <- subset(lw, !is.na(as.numeric(lw$PCryonics)))
R> cor.test(as.numeric(lw$TimeinCommunity), as.numeric(lw$PCryonics))

Pearson's product-moment correlation

data: as.numeric(lw$TimeinCommunity) and as.numeric(lw$PCryonics)
t = 0.1946, df = 1065, p-value = 0.8457
alternative hypothesis: true correlation is not equal to 0
95 percent confidence interval:
-0.05407 0.06595
sample estimates:
R> cor.test(as.numeric(lw$TimeinCommunity), as.numeric(lw$CryonicsStatus))

Pearson's product-moment correlation

data: as.numeric(lw$TimeinCommunity) and as.numeric(lw$CryonicsStatus)
t = 4.157, df = 1065, p-value = 3.485e-05
alternative hypothesis: true correlation is not equal to 0
95 percent confidence interval:
0.06685 0.18497
sample estimates:

Plotting time in community against belief in cryonics shows nothing, per the lack of correlation:


But visually, at least, there's also nothing going on with likelihood of signing up despite the small correlation:


So the effects we're looking at can't be very big.
(Reply) (Thread)
From: (Anonymous)
2013-01-02 07:26 am (UTC)




As you elsewhere appear to be aware, the correct form is:

Remember: as.numeric(factor(5:10))
[1] 1 2 3 4 5 6
(Reply) (Parent) (Thread) (Expand)
[User Picture]From: naath
2013-01-01 05:44 pm (UTC)
No-one has yet demonstrated that cryonics works. So it's the question of how much money are you willing to pay for something that has some unknown chance of working to give you some unknown amount of extra life at some unknown point in the future...

Now, I'd certainly like some extra life! But on the other hand I have uses for my money in the here-and-now. Also as a frequent on-road cyclist it's most likely I'll die of having a bus turn me to road-jam which, er,well you have to have something worth freezing for cryonics to work even in theory right?

I discovered in physics class that I have a very unusual ability to say "no idea" when asked something I have no idea about. A thing I hate a lot is other people trying to push me to "have an opinion" about something that I HAVE NO IDEA about; not even enough of an idea to attempt a reasonable estimate. Maintaining this zen state of ignorance is quite hard when asked to make practical choices about things of course.
(Reply) (Thread)
From: unnamedlw
2013-01-01 05:53 pm (UTC)
I did some analyses of the cryonics question last year, and the main result was that people with strong ties to Less Wrong were less likely to assign a high (>50%) probability to cryonics working.

This year, if you compare people who have read "nearly all of the sequences" (n=297) with those who "never even knew they existed until this moment" (n=90), the mean probabilities are similar (18.0 vs. 15.7, not significantly different), but the distributions are very different. The sequence-readers are much less likely to assign a probability of p<.05 to cryonics (27% of sequence-readers vs. 50% of sequences-unaware), and that difference is almost entirely concentrated in those who assigned a probability of 0 (2% vs. 21%). Sequence-readers are much more likely to assign a probability of at least .05 but less than .20 (41% vs. 21%); that makes up most of the difference (and leaves about 30% of each group assigning a probability of at least .20). Graph here, broken down into 6 categories:

If you look at p(cryonics) by cryonics status, the groups that give the highest probability (and are most likely to give p>.50) are the ones who are not signed up but would like to sign up. The people who already are signed up for cryonics have the narrowest distribution, with few giving p<.05 and few giving p>.50. Graph here ("signed up" group on the far right, "would like to" groups next to them towards the right, "never thought about it" group on the left):
(Reply) (Thread)
[User Picture]From: xiphias
2013-01-02 12:42 am (UTC)
So, basically, your thoughts on cryonics are Pascal's Wager based on Cartesian mind-body duality?
(Reply) (Thread)
From: (Anonymous)
2013-01-02 02:53 am (UTC)
It's only Pascal's Wager if you think that any expected value calculation is Pascal's Wager; this one, as has been pointed out already, doesn't resemble the canonical Wager very closely. Descartes is not relevant or mentioned at all and I have no idea why you brought him up.
(Reply) (Parent) (Thread)
From: (Anonymous)
2013-01-02 05:36 am (UTC)
Vaguely related annoyance: Kickstarter. Oh, the debates I've seen people get into over whether putting money into a KS project should be called "buying" or "investment" or "donation", with each of the groups being called by the others naive, cynical, and ignorant respectively. Because apparently the only sorts of transactions that exist are those where you have a 100% percent guarantee of getting stuff, and those where you might as well just put it all on roulette, and there's no middle ground.

-ari (who's not logged in because LJ is the one site on the internet that's more often hilariously slow or completely down than Bastion)
(Reply) (Thread)
From: (Anonymous)
2013-01-02 02:35 pm (UTC)
How did you average the probabilities? I suspect the best way to do it is to average the log-odds.
(Reply) (Thread)
From: deiseach
2013-01-03 06:47 pm (UTC)
My objections to cryonics don't rely on mathematical probabilities (because I am hopeless at maths), they boil down to: (1) do I think cryonics will ever work? Possibly, at some future point but at present - no. Have they frozen and then revived any animals such as dogs to test how the processes work or are they hoping that in fifty/two hundred years' time, medical science will be able to fix the damage that freezing and thawing out causes? Besides that you have to be legally dead when frozen, and if they can revive the 'dead' in the future, why do you think they'll bother with reviving frozen dead when they will have a plentiful supply of their own population to revive?

(b) Okay, imagine that you are dropped into the past of one or two hundred years' ago by time machine. Explain to me how, with your current skills or abilities, you are going to fit into society and make a living. Then tell me how you think you're going to fit into and make a living in the society of one or two hundred years from now, when they can have uplifted weasels in entry-level jobs working to cromify the tapabules rather than educating and training some relic of the past in order to get an entry-level job cromifying the tapabules.
(Reply) (Thread)
From: (Anonymous)
2013-02-06 11:41 am (UTC)

you can buy cheap mulberry bags uk sale here

ryxmp [url=http://www.im-mulberrybags.co.uk]mulberry bags[/url] yyyyum http://www.im-mulberrybags.co.uk dwlzm [url=http://www.im-mulberryoutlet.co.uk]mulberry outlet[/url] blcyek http://www.im-mulberryoutlet.co.uk yxiue [url=http://www.pay-mulberrybags.co.uk]mulberry outlet[/url] hebqoj http://www.pay-mulberrybags.co.uk xyzr [url=http://www.online-mulberry.co.uk]mulberry outlet[/url] pqzhif http://www.online-mulberry.co.uk nqfhl [url=http://www.goodcelinehandbags.com]mulberry outlet[/url] kavpio http://www.goodcelinehandbags.com fdmud [url=http://www.onlinecelinebags.com]mulberry outlet[/url] pjgoqi http://www.onlinecelinebags.com tkwn
(Reply) (Thread)
From: (Anonymous)
2013-03-04 11:12 pm (UTC)

where to use cheap beats by dre for sale?

ekccl [url=http://www.beatsbydrenewsale.com]beats by dre[/url] qfkgk http://www.beatsbydrenewsale.com yqssk [url=http://www.beatsbydrelo.com]cheap beats by dre[/url] ccstb http://www.beatsbydrelo.com wnapj [url=http://www.beatsshop2013.com]cheap beats by dre[/url] weazn http://www.beatsshop2013.com evnvz [url=http://www.vip-beatsbydreoutlet.com]beats by dre[/url] iihmb http://www.vip-beatsbydreoutlet.com wxnik [url=http://www.beatsbydreonsale1.com]cheap beats by dre[/url] cmuxu http://www.beatsbydreonsale1.com ksfwh [url=http://www.cheapbeatsbydreonsale1.com]dr dre beats[/url] wgrly http://www.cheapbeatsbydreonsale1.com lmeuy
(Reply) (Thread)
From: (Anonymous)
2013-03-09 01:22 pm (UTC)

where to buy louis vuitton handbags online sale?

uqa [url=http://louisvuittonoutletbny.com]discount louis vuitton[/url] xny http://louisvuittonoutletbny.com ayfc [url=http://louisvuittonboutlet.com]louis vuitton outlet[/url] xejl http://louisvuittonboutlet.com uce [url=http://hollisterboutlet.co.uk]Hollister Outlet[/url] ldq http://hollisterboutlet.co.uk fpfp [url=http://okhollisteroutlet.co.uk]Hollister Jeans[/url] tts http://okhollisteroutlet.co.uk jlz [url=http://beatsbydrehfwh.co.uk]Beats By Dre UK[/url] hfm http://beatsbydrehfwh.co.uk mlp [url=http://christianlouboutinac.com]christian louboutin outlet[/url] nsa http://christianlouboutinac.com hsk
(Reply) (Thread)
From: (Anonymous)
2013-03-09 01:33 pm (UTC)

where to buy cheap louis vuitton online sale?

zod [url=http://www.louisvuittonoutletmvpo.com]louis vuitton handbags[/url] yjn http://www.louisvuittonoutletmvpo.com yrr [url=http://www.ccelinebags.com]celine bags[/url] zky http://www.ccelinebags.com qim [url=http://www.beatsbydre-chen.com]dr dre beats[/url] nut http://www.beatsbydre-chen.com xajs [url=http://cheapdrdrebbeats.com]beats by dre[/url] yrtp http://cheapdrdrebbeats.com cfj [url=http://christianlouboutinab.com]christian louboutin outlet[/url] fqm http://christianlouboutinab.com hfi
(Reply) (Thread)
From: (Anonymous)
2013-03-09 10:30 pm (UTC)

where can i buy cheap louis vuitton online outlet

haowcw http://abc-louisvuittonoutlet.com uqaaen http://www.canadagoosehut.com xygakz http://www.mymontblancforcheap.com swvrtv http://beatsbydrecheapp.com egztqe http://alouisvuittonoutlet-au.com nivhxi [url=http://abc-louisvuittonoutlet.com]louis vuitton outlet[/url] nzite [url=http://www.canadagoosehut.com]canada goose outlet[/url] mksdy [url=http://www.mymontblancforcheap.com]mont blanc pens[/url] khcmr [url=http://beatsbydrecheapp.com]cheap beats by dre[/url] zvytbn [url=http://alouisvuittonoutlet-au.com]louis vuitton sale[/url] yecs
(Reply) (Thread)
From: (Anonymous)
2013-03-09 11:20 pm (UTC)

you can get louis vuitton handbags sale here

xzrbuh http://pa-louisvuittoncheap.com pspwak http://www.mccanadagooseoutlet.com fooptb http://www.sale-cheapmontblanc.com vfdufl http://cheaperbeatssbydre.com bdclzq http://palouisvuittonoutlet.com ankylw [url=http://pa-louisvuittoncheap.com]louis vuitton handbags[/url] xxanx [url=http://www.mccanadagooseoutlet.com]canada goose jacket[/url] qahpg [url=http://www.sale-cheapmontblanc.com]cheap mont blanc[/url] nnbzn [url=http://cheaperbeatssbydre.com]dr dre beats[/url] bbhrzk [url=http://palouisvuittonoutlet.com]louis vuitton bags[/url] krgz
(Reply) (Thread)
Page 1 of 4
<<[1] [2] [3] [4] >>