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Open thread, March 13 - March 19, 2017

2 Post author: Elo 13 March 2017 03:46AM

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Comments (116)

Comment author: niceguyanon 16 March 2017 02:24:53PM *  3 points [-]

I am reading Expecting Better, a book about evidence based pregnancy and in it, there are passages about the high rates of C-sections and why it might be. The conclusion was that one medical intervention, whether by drugs or over-monitoring, usually leads to another and another and you end up with a C-section. Non C-section births have better outcomes. So you want to avoid it if you can. The book also mentions that the use of a doula can reduce rates of C-sections to less than 10% from modern U.S. rates of 30%. That is very impressive. Why and how?

I interviewed a professional doula and just asked quite plainly how does her service provide such a dramatic decrease in C-sections. Her personal experience if she is to be believed, is in line with the 10% figure. Her answer is that by being an advocate for the mother and delaying any unnecessary medical intervention in the delivery room, and by providing a calm and coping environment for the mother, she is able to have better outcomes. This means not bringing the mother to the hospital too early.

The way she described it was that the delivery room is a high stress situation where there are doctors and nurses who are supposed to be doing something, and when nothing is happening, they tend to make things happen, when the right thing to do is just wait. Doulas often go to your home before you are in active labor and bring you to the hospital no earlier than you have too. This is the key, by going to the hospital too early you are increasing your chances of having some medical intervention.

So the take away is that there is good evidence that doulas are effective and do so by:

  • timing the right time to go to the hospital
  • preparing a mother to be calm and mentally strong
  • advocating for a mother in the delivery room for more time, before intervention
Comment author: MrMind 17 March 2017 03:35:26PM *  2 points [-]

Non C-section births have better outcomes. So you want to avoid it if you can.

This is highly suspicious to me. Do C-sections follow or cause worse outcomes?

Comment author: niceguyanon 17 March 2017 06:59:15PM 0 points [-]

I think there was a distinction made between planned C-sections and unplanned C-sections (medical emergencies), so that they were able differentiate outcomes following emergencies like a breech baby vs a completely planned C-section. And I think it showed that show C-sections overall were more risky than vaginal birth and long term health was better for vaginal births.

I haven't done any google fu on this topic, other than reading a few passages in a book.

Comment author: SnowSage4444 17 March 2017 07:10:21PM 0 points [-]

It would make more sense if C-sections were better. After all, nature is notoriously irrational and inefficient.

Comment author: Viliam 18 March 2017 09:57:31AM 0 points [-]

Scar tissue is less flexible than the original one, and flexibility in the areas that need to be stretched during childbirth is important. Having a C-section when you don't need one increases the chance that the next time you will need one.

...which probably doesn't seem like a problem if you have already decided to have C-sections only.

Arguably, doing childbirth the "unnatural" way can mess up with your or your baby's instincts, because they were evolved expecting certain circumstances. Some instincts depend on timing. I am not sure if this is the situation here, but some people prefer to play it safe.

Seems to me that frequently used arguments for (medically unnecessary) C-section is that it is supposed to be less painful and heal better. As far as I know, the better healing was never proved empirically; and with pain it seems like you are kinda trading more intense pain in short time for less intense pain in long time; but I am not certain about these two things.

Comment author: Douglas_Knight 18 March 2017 06:17:52PM 0 points [-]

Arguably, doing childbirth the "unnatural" way can mess up with your or your baby's instincts, because they were evolved expecting certain circumstances. Some instincts depend on timing. I am not sure if this is the situation here, but some people prefer to play it safe.

That seems totally crazy to me. Claims about transfer of bacteria (both good and bad) are much more plausible differences with a C-section.

Comment author: Viliam 18 March 2017 06:35:37PM *  0 points [-]

More crazy than this?

Lorenz demonstrated how incubator-hatched geese would imprint on the first suitable moving stimulus they saw within what he called a "critical period" between 13–16 hours shortly after hatching.

Comment author: Lumifer 16 March 2017 02:39:37PM *  2 points [-]

a book about evidence based pregnancy

!!!

Non C-section births have better outcomes.

The devil is in the details: what you control for and what you don't. Compare: "Not being in a hospital bed has better outcomes than being in a hospital bed".

So the take away is that there is good evidence that doulas are effective

Maybe the book cited some, but you didn't show any.

Comment author: niceguyanon 16 March 2017 03:01:19PM 1 point [-]

Ideally 100% of those that medically need C-sections will get it, and those that don't wont.

I think there was a study that was cited in the book about the reduced C-sections rates, but of course the devil is in the details like you say, best to do your own research. I have personally updated my beliefs in favor being more resilient to time pressures of labor and that use of a doula isn't just a waste of money as I previously had thought.

Comment author: Lumifer 16 March 2017 03:06:55PM 0 points [-]

Ideally 100% of those that medically need C-sections will get it, and those that don't wont.

You speak as if women don't have preferences. Hint: they do.

Comment author: niceguyanon 16 March 2017 03:11:49PM 1 point [-]

I am constantly reminded of that fact daily!

Comment author: Lumifer 16 March 2017 03:21:07PM 0 points [-]

:-)

Comment author: Viliam 17 March 2017 11:28:14AM *  1 point [-]

In my country the C-sections rate is very high (not sure I can trust my memory on the exact number). We pretty much decided to have our child born in a neighbor country, just to reduce the related risks, even if that included a risk that any medical complication would make the costs skyrocket (because our health insurance system does not like this kind of healthcare shopping).

From what I was told, seems like the most important factor is that C-section is more convenient for the doctor. For example, doctors can choose exact timing, to avoid a situation when two babies decide to get naturally born at exactly the same moment. Or they can make more babies get born during the day, when there is more staff at the hospital, and less during the night. (There are also other ways to artificially influence the timing, and yes, those are used too.) Another factor is that in my country it is more-or-less mandatory for mother during the childbirth to lie on her back... which again is most convenient for the doctor, but also happens to increase some risks associated with childbirth (which can be then conveniently solved by the C-section). If I understand it correctly, the position on the back is more dangerous because the child needs to be pushed uphill (over the tail bone).

What is even worse, when there are too many C-sections, a feedback loop appears -- suddenly people (both the doctors and the patients) need to protect their egos by rationalizing that, actually, C-section is the best way to go. Which in turn further increases the rate of the C-sections, because if "everyone is doing that" then it is "perfectly normal" and certainly "happens for a good reason", and people who think otherwise must obviously be wrong. So now you have mothers expecting to be given C-section, because that's how it is usually done. And you have doctors giving C-sections at a smallest opportunity, because that's what most mothers want them to do.

And communicating this with doctors is almost impossible. When you mention that, they will start lecturing you that sometimes the C-section is necessary to save the baby's or mother's life or health. And when you say "okay, of course in such case I would want you to do it, but if there is no complication, then I don't want you to do that needlessly... I am even willing to pay to extra to compensate for all related inconvenience", then the doctor usually gets offended or treats you like an idiot and says that "of course we are doing that only when it is necessary". Except, comparing statistics across countries shows that somehow, in neighbor countries it is "necessary" in maybe 15% of cases, but in our country it is close to 50%... but of course, for each specific case the doctor can argue that this specific case happened to be an exception where the C-section was necessary. And no, they are not going to allow the mother to give birth in a different position, because that is simply not how things are done, full stop. (Cross the border to the nearest country though, and the local doctors are like "yeah, sure, no problem".)

Generally, comparing medicine across countries can make you mad. Seems like in each country, doctors have a consensus on how things are supposed to be done, and they always claim that their opinions are backed by science. Yet somehow the "science" says sometimes completely opposite things in different countries. (I suspect "science" is a shorthand here for "what they taught me at university, a few decades ago".) And if you look into peer-reviewed journals to find what the science actually says, you will usually get yet another opinion. (Though we noticed the trend that the peer-reviewed journals usually agree more with the "science" of our neighbor country than with the "science" of my country.)

Comment author: Douglas_Knight 18 March 2017 06:15:38PM 0 points [-]

Without claiming that it is directly relevant to the question, let me quote Atul Gawande, from "The Score: How childbirth went industrial"

Yes, he said, many studies did show fabulous results for forceps. But they only showed how well forceps deliveries could go in the hands of highly experienced obstetricians at large hospitals....Forceps deliveries are very difficult to teach—much more difficult than a C-section

Gawande is great. Collect them all. Also, Lewis Thomas.

Comment author: fubarobfusco 17 March 2017 02:56:59AM 2 points [-]

Composing a comment and then deciding not to post it can be a good form of rubber-ducking.

Comment author: Viliam 17 March 2017 11:34:01AM *  0 points [-]

Or an e-mail. (If you leave the "To:" field empty, there is no risk of sending it accidentally.)

Comment author: MrMind 17 March 2017 08:25:10AM 0 points [-]

Ha, it's true, good catch. I usually let a long comment ferment some minutes before clicking the 'comment' button. Sometimes I end up deleting the whole thing.

Comment author: MaryCh 14 March 2017 08:02:17PM *  2 points [-]

I'm reading The Last Psychiatrist's 'Don't hate her because she's successful' and having trouble with:

'No, she just means when you get married, to pick someone who supports your goals."  In other words, a business relationship?  Arranged marriage, only this time by Match.com's algorithm?  "No, a marriage based not on passion but on mutual respect and shared values--" Stop, listen to what you are saying.  Why would you want a man who agreed to this?  Why would a man want a woman who thought like this?'

I mean, why would I not want a man who agreed to this? It seems so obvious.

Edit - I am speaking as a woman of low lust levels (I think - at least some of my friends seem to have higher lll), so I don't value 'passion' highly (either that, or I misread 'passion' and it includes something of what I would classify as 'shared values' - it is also possible.)

Comment author: username2 15 March 2017 08:29:58AM 1 point [-]

I mean, why would I not want a man who agreed to this? It seems so obvious.

Why? Genuine question because no, it is not obvious to me.

Comment author: MaryCh 15 March 2017 11:15:28AM 0 points [-]

Because I have (I think) low leves of carnal desires, and a desire for external validation of my cleverness and justness. And I certainly don't want a marriage with a man who cannot respect me.

Comment author: username2 15 March 2017 07:12:16PM 1 point [-]

The you should edit/clarify your original post as I had the opposite interpretation, hence confusion.

Comment author: Oscar_Cunningham 14 March 2017 10:19:30PM 0 points [-]

Obviously a husband who supports your goals is better than one that doesn't. But if your potential husband doesn't support your goals then they must not value your happiness and fulfilment, in which case your relationship has already failed. There's no possible potential husband who it's a good idea to marry except for the single factor that they don't support your goals. Such a person can't exist. So it's just not a useful decision criterion to ask whether they support your goals; there are other criteria which are strictly better.

Comment author: 9eB1 15 March 2017 07:44:34AM *  5 points [-]

I've read a lot of TLP and this is roughly my interpretation as well. Alone's posts do not come with nicely-wrapped thesis statements (although the conclusion of this one is as close as it gets). The point she is making here is that the system doesn't care about your happiness, but you should. The use of "goals" here isn't the LessWrong definition, but the more prosaic one where it implies achievements in life and especially in careers. Real people who want to be happy do want someone who is passionate, and the juxtaposition of passionate with "mutual respect and shared values" is meant to imply a respectful but loveless marriage. If someone asks you about your partner and you most central characteristic you have to define your marriage is "mutual respect and shared values" that says something very different than if your central characteristic is "passionate." It's sterile, and that sterility is meant to suggest that the person who says "passionate" is going to be happier regardless of their achievements in the workplace.

Comment author: username2 15 March 2017 08:32:27AM *  1 point [-]

Passion fades. If you want a lifelong relationship, and not an eventual divorce, it does require comparability / sharing of life goals.

Comment author: Good_Burning_Plastic 15 March 2017 09:29:57AM 0 points [-]

I was about to comment something to the effect that those two desiderata aren't mutually exclusive -- but the Berkson paradox thing does apply.

Comment author: MaryCh 15 March 2017 11:57:36AM 0 points [-]

I think I understood the place, and I almost agree with you, but

There's no possible potential husband who it's a good idea to marry except for the single factor that they don't support your goals. Such a person can't exist.

I think it happens. I know a person in Crimea who wanted to live and work according to her specialty in Ukraine, but her groom did not want to leave his (and hers) homeland, the Crimea, and they married and live there. If there are people who decided to marry, and (hypothetical, but I think probable) people who decided not to, doesn't it show that some of them decided 'not sharing my goals' is enough of a reason?

Comment author: Oscar_Cunningham 15 March 2017 02:35:50PM 0 points [-]

They had two conflicting vaues and made a choice, but I would hope that the groom still support her goals within constraints, like "Thank you for agreeing to stay in Crimea with me, lets plan together how you can achieve success while staying here."

Comment author: MaryCh 15 March 2017 02:51:50PM 0 points [-]

From what I heard of him he's wonderful and probably does that:)

Comment author: Daniel_Burfoot 14 March 2017 05:14:43PM 2 points [-]

Why is it so hard to refrain from irrational participation in political arguments? One theory is that in the EEA, if you overheard some people talking covertly about political issues, there was a good chance that they were literally plotting against you. In a tribal setting, if you're being left out of the political conversation, you're probably going to be the victim of the political change being discussed. So we've probably evolved a mental module that causes us to be hyperaware of political talk, and when we hear political talk we don't like, to jump in and try to disrupt it.

Anyone have any good mind hacks to help stay out of political conversations?

Comment author: Viliam 15 March 2017 11:28:25AM *  4 points [-]

When people are plotting, there is going to be an "inner group". And your winning choices are either to join the "inner group" (if you predict it will win) or express disinterest publicly (if you predict it will lose). This is true both in EEA and at high school.

In other environments, people overestimate their importance essentially for two reasons: First, with larger numbers of people in general, each individual matters less. A marginal new ally is more important to a group with ten members, than to a group with thousand members. Second, mere numbers of people matter less than their power. For a high-school clique another average person can be a valuable asset, but a political party some people are orders of magnitude more worth than an average person.

Anyone have any good mind hacks to help stay out of political conversations?

I try to remind myself of (what I believe to be) the big picture. If you are going to participate in online political debates, you essentially have two choices to make: (1) is this going to be a casual opinion expressing, or are you going to play it like a pro? and (2) are you going to present sane opinions, or will you make yourself into a two-dimensional caricature of human being?

I believe that if you are not playing it like a pro, you are just wasting your time, achieving nothing good (neither for you, nor for the world in general). I also believe that unless you are already very famous, presenting sane opinions is a losing strategy (because sane opinions are suboptimal for signalling loyalty to a tribe). Therefore, most likely the only winning strategy for you is in the "insane pro" quadrant. Now the question is whether you are going to do it, or if it seems like too much work and too little fun. For me, laziness usually wins at this point.

To explain, "doing it like a pro" means that instead of commenting on other people's websites or social networks, you will make your own trademarked content. You will post articles on your own website (where you have absolute moderator powers), and where you will build your own personal reader base. (A YouTube channel is also okay, but always have a Plan B in mind if YouTube decides they don't like you; for example because your political opponents decide to spam your videos with fake complaints; that could happen any time and could ruin overnight everything you built.) Do not forget a Patreon link, or some other way to monetize your hard work!

And by "two-dimensional caricature" I mean this: humans are complex, but they enjoy simple solutions. Also, political fans are more likely to punish disagreement than to reward agreement. That means, if you only express your opinion on one issue, and your opinion on that issue is completely black-and-white, congratulations, half of the politically active people will think you are a genius! (The other half will think you are a moron, but that's inevitable.) However, if you express your opinion on ten issues, guess what: only one reader in a thousand will think you are a genius, and the remaining 999 will think you are a moron. (The disagreement on one important topic will hurt them more than the agreement on nine topics will make them happy.) Oh, and if you express arguments both in favor and against something, then everyone is going to think you are a moron. To optimize for reader base size, you must care fanatically strongly about one issue, and not to touch anything else. Of course, you are allowed to have more than one opinion, as long as those opinions are strongly correlated in the population.

So, at this moment I (1) have a specific plan how to do political commenting correctly, and (2) realize that I actually don't want to do it this way, because it's too much work and too little fun. On the other hand, knowing the optimal way, I am now less tempted to do it the obviously suboptimal way.

To overcome the temptation, make the whole idiocy visible to your System 1, so now it will feel repulsive.

Comment author: Lumifer 15 March 2017 03:35:24PM 0 points [-]

If you are going to participate in online political debates, you essentially have two choices to make:

There is the third choice, which is the best: troll :-D

I tend to treat online political discussions as a source of amusement. Better than soap operas.

Comment author: tristanm 14 March 2017 08:19:56PM 0 points [-]

I see no issue with engaging in rational political discussion. The key is avoiding the overly tribal arguments that proliferate throughout social media. I think those are a lot like sports arguments - you want to join in just to root for your team. I doubt that it has to do with the kind of social gossip that was used to determine the status hierarchy in our early tribal environments - that still exists in almost the same form as it did then I think.

Comment author: Thomas 13 March 2017 08:05:52AM *  2 points [-]
Comment deleted 15 March 2017 01:53:34PM [-]
Comment author: Oscar_Cunningham 15 March 2017 06:04:12PM 0 points [-]

Do you mean that a score arbitrarily close to 0 can be achieved?

Comment author: Thomas 15 March 2017 02:41:02PM *  0 points [-]

What shape could that possibly be?

Comment author: Good_Burning_Plastic 15 March 2017 06:19:17PM *  0 points [-]

I was about to say "Since you never specified that the shape must be a measurable set ..." and link to here, but since you mention the area of the shape, you do (implicitly) require it to have one.

Comment author: Oscar_Cunningham 15 March 2017 07:29:52PM 0 points [-]

Are all those pieces congruent though?

Comment author: Thomas 15 March 2017 07:12:34PM 0 points [-]

Yes, you are right. I want the area of the shape and therefore no kinky shapes are permited.

Comment author: Oscar_Cunningham 13 March 2017 07:09:46PM 0 points [-]

My first thought is that we can't hit exactly 0 because gur engvb bs gurve nernf vf veengvbany, but we might be able to get arbitrarily close.

Comment author: Thomas 13 March 2017 08:05:02PM 0 points [-]

If we could come arbitrarily close, then some very weird covering shapes would be possible.

Comment author: 9eB1 13 March 2017 10:19:33PM 0 points [-]

You can come arbitrarily close by choosing any tiling shape and making it as small as necessary.

Comment author: Oscar_Cunningham 13 March 2017 10:57:07PM *  0 points [-]

No, because the degree of failure of the tiling is judged against the area of the covering shape.

Comment author: 9eB1 14 March 2017 01:33:04AM *  0 points [-]

This is one of the more confusing problem statements, but I think I understand. So if we choose a regular hexagon with height = 0.5, as in this link, the scoring for this solution would be ((area of triangle - area of hexagon) + (area of square - 3 * area of hexagon)) / area of hexagon?

edit: Gur orfg fbyhgvba V pbhyq pbzr hc jvgu jnf whfg gur n evtug gevnatyr gung'f unys gur nern bs gur rdhvyngreny gevnatyr. Lbh pna svg 4 va gur fdhner naq gjb va gur gevnatyr, naq gur fpber vf cbvag fvk. V bayl gevrq n unaqshy bs erthyne gvyvatf gubhtu.

Comment author: Oscar_Cunningham 14 March 2017 03:20:46PM *  1 point [-]

I can beat your solution and get a score of 0.433....

Gnxr gur pbirevat funcr gb or gur jubyr fdhner naq pbzcyrgryl snvy gb pbire gur gevnatyr.

:-P

EDIT: Va snpg, jul abg trg n ernyyl tbbq fpber ol gnxvat n pbzcyrgryl tvtnagvp funcr gung qbrfa'g pbire nalguvat.

Comment author: Thomas 14 March 2017 04:29:25PM 0 points [-]

Yes, well ... If the shape is gigantic and therefore doesn't cover anything ... this is a cunning solution, but in a sense trivial.

A non-trivial solution would be (even) better. ;)

Comment author: Oscar_Cunningham 14 March 2017 08:56:41PM *  1 point [-]

Okay, here's a non-trivial answer. I believe I can get arbitrarily close to a score of 1/sqrt(3) = 0.57735... .

Pick any natural number n, and let x = sqrt(3)/2. Using the theory of continued fractions one can find natural numbers p and q such that q > n and x < p/q < x + 1/(4sqrt(3)q^2). Now let our covering shape be a right angled triangle with sides 1/(2p) and x/p. The area is x/(4p^2). Clearly 2p^2 such triangles can cover the equilateral triangle exactly.

Now consider how many we can fit in the square. By using two of our covering triangle we can make a rectangle of sides 1/(2p) and x/p. By arranging such rectangles in a 2p by q grid we can perfectly tile a big rectangle with sides 1 and qx/p. Since x < p/q we have qx/p < 1, so this rectangle fits into the square.

The remaining area is 1 - qx/p, and since p/q < x + 1/(4sqrt(3)q^2) we have that this area is less than 1/(4sqrt(3)pq). Comparing this to the area of our covering triangle we find that our score is at most (p/q)(1/x)(1/sqrt(3)) which is less than (x + 1/(4sqrt(3)q^2))(1/x)(1/sqrt(3)) which is less than (1+1/(4sqrt(3)xn^2))(1/sqrt(3)). Since n was arbitrary this can come arbitrarily close to a score of 1/sqrt(3).

EDIT: I made a picture of the tiling of the square when p=13, q=15. The uncovered area is the tiny red line at the top. The score is 0.57756... .

Comment author: Thomas 15 March 2017 06:06:16AM 0 points [-]

I will publish my solution next Monday.

Comment author: Thomas 14 March 2017 06:24:15AM 0 points [-]

The score point is not 6 at your solution.

Comment author: Oscar_Cunningham 14 March 2017 08:01:43AM 0 points [-]

They means point six, i.e. 0.6. In fact their score is 0.6188....

Comment author: Thomas 14 March 2017 08:34:03AM 0 points [-]

True.

As I also see now, my problem formulations are a problem before the problem itself.

Comment author: Oscar_Cunningham 14 March 2017 08:59:25AM 0 points [-]

That's okay since the actual problems are interesting.

Comment author: Oscar_Cunningham 13 March 2017 11:47:57AM 0 points [-]

What do you mean by

no part of the covering shape may lie outside both polygons.

and by

A shape that leaves a smaller percentage of its own area uncovered is a better solution.

?

Comment author: Thomas 13 March 2017 01:34:05PM *  1 point [-]

You may not put the covering shape (even partly) outside the triangle or square.

The edges of both polygons may be tangents, but not secants of the covering shape.

Those covering shape has its own area - A. By tiling those two polygons some area could stay uncovered. This whole uncovered area of both polygons together has to be a smallest possible percentage of A. Preferably 0.

Comment author: gjm 13 March 2017 04:29:21PM 2 points [-]

So is the following what you mean?

We have S, the unit square, and T, the unit-side equilateral triangle. We are to find some other shape A, and consider copies (to which Euclidean congruences have been applied) A1 ... Am lying within S and pairwise disjoint (aside from boundaries) and B1 ... Bn lying within T and pairwise disjoint (aside from boundaries) -- but we do not require that the union of the A's be all of S, nor that the union of the B's be all of T. And the puzzle is then to choose A and those congruences so that the ratio (total area of S and T left uncovered) / (area of A) is as small as possible (ideally, of course, zero).

Is that right?

(If so, then the original problem statement's use of the verb "tile" confused the hell out of me.)

Comment author: Thomas 13 March 2017 05:44:25PM 0 points [-]

Yes, this is the case, I couldn't have put it better myself! ;)

Comment author: michaelkeenan 13 March 2017 06:02:49PM 1 point [-]

I hope someone can help me find a blog post or webpage that I've seen before but can't find: it's someone describing a power law of scientists. There's a top level who have drastically more output than the level below, who are drastically more productive than the level below that. There's only a few at the top level, and a few hundred at level 2, and a few thousand at level 3. I think he mentions one scientist being level 0.5 - notably more productive than almost anyone else. It was on a relatively unstyled website, maybe Scott Aaronson's.

Anyone familiar with that?

Comment author: satt 13 March 2017 07:50:25PM 5 points [-]
Comment author: michaelkeenan 13 March 2017 09:15:13PM 1 point [-]

Thank you!

Comment author: morganism 13 March 2017 09:33:09PM 1 point [-]

and a blogpost on hiring those "star players", and the outlooks for the rest...

STEM: Still No Shortage On a myth that just won’t die

https://medium.com/i-m-h-o/stem-still-no-shortage-c6f6eed505c1#.d8prbrkvk

Comment author: morganism 18 March 2017 10:28:51PM 0 points [-]

Native GPU programming with CUDAnative.jl

http://julialang.org/blog/2017/03/cudanative

"You can now write your CUDA kernels in Julia, albeit with some restrictions, making it possible to use Julia’s high-level language features to write high-performance GPU code."

"The programming support we’re demonstrating here today consists of the low-level building blocks, sitting at the same abstraction level of CUDA C. You should be interested if you know (or want to learn) how to program a parallel accelerator like a GPU, while dealing with tricky performance characteristics and communication semantics."

Comment author: Viliam 18 March 2017 10:24:05AM *  0 points [-]

On science reddit there is a link to an article about confirmation bias. About 1500 comments in the discussion are deleted, here are some examples:

So how do you work to get out of this? I'm really afraid that I'm falling into thought bubbles and can't find my way out. I've always believed in many different ideas but as of recent, I feel like I'm in an echo chamber.

Doubt everything and become a cynical son of a bitch that nobody wants to be around. Or self-reflect regularly. It's a thin line. Good luck.

What gives a person the ability to self reflect and to question what they believe? I was once a very strong fundamentalist christian and far right republican who believed any evidence against my beliefs were lies. Somehow though I was able to break out of both of those things after evaluating them. I don't know what was different about the initial evaluation that caused the break other than it seemed to be self lead someone through tangential and research. I have no clue how to apply it to other people. I've found even very gentle, bible-backed evidence causing my family and friends to become defensive and angry and immediately throw up walls. I'm not even sure how to make sure I am evaluating new ideas outside of my own bubble.

You could try looking into a personality trait known as "need for closure." People with a high need for closure are rigid thinkers. They are very intolerant of ambiguity and are uncomfortable challenging their worldview, and thus tend to form beliefs quickly and are then less open to changing them. Conversely, people who have a low need for closure (this can also be termed "need for cognition") are not as uncomfortable with ambiguity and are more cognitively flexible. They are more interested in actively constructing their understanding of the world, and tend to be more intellectually engaged and comfortable with changing their beliefs. I believe variance of this trait plays a role in answering the question of why some people change their worldview over time and others do not. [...] there is some situational variability as well. People who are stressed, angry, tired, hungry, pressed for time, etc. demonstrate much less cognitive flexibility than they otherwise would have.

It's been my finding that you can never convince someone if they don't want to be convinced and you announce your opposition to their ideas before entering the debate. It's much more effective to go for the Socratic method. Make them think they're teaching you and use well placed questions to force them to think on thoughts that they might otherwise be uncomfortable with. And they'll do it because it the idea of gaining a convert usually outweighs the fear of this "innocent" corrupting their viewpoint.

Just try to remember that there are usually, at minimum, two sides to any argument, and those sides usually have, at least at some level, reasonable and arguable points that favor them. If you constantly challenge your own beliefs and argue convincingly for sides you may personally disagree with it can, at minimum, help you see things from the opposite point of view and empathize with the beliefs.

Actively pursue disproving what you believe. Play devils advocate with yourself. If you think you can't poke any more holes in what you believe, look for people who can; others may have ideas or arguments you haven't thought of. It also helps to work to identify your core values and rank them. Johnathan Haidt's breakdown of what these may be is popular, but they are only one way of identifying and categorizing them. Use that as a starting point and Google your way to some criticism. Weight the criticism. There's also a sub-reddit, /r/changemyview, that I don't really frequent, and so, can't really endorse or criticize, but I know exists. Just always question everything and step outside your comfort zone. Embrace intellectual conflict, but keep it classy; argue, don't fight.

Realize that it's OK to have an opinion without expressing it to others. I have deeply held beliefs on the usefulness of religion and the proper way to hang toilet paper, but I don't generally share them because I don't enjoy arguing, and I don't need validation. They're beliefs, not facts, so who cares what I think? By the same token, also know that it's OK to have NO opinion on something (particularly things which you accept you're unable to affect). You can listen to both sides of a debate, and choose neither. I'm largely agnostic about politics, for example.

On the other hand, if you do care about an issue and want to know more for the sake of empathy, asking people for their point of view without the need to give an opinion on it works just fine too.

I guess the comments broke some rule, probably that they don't present scientifically supported statements. It's still sad to see so much quality text removed. I understand that this is probably necessary to prevent a slippery slope from "science" to "just posting my random opinions". Still, it's sad.

Comment author: morganism 17 March 2017 10:59:13PM 0 points [-]

This looks like a great tool, a good philanthropy target. Simple, cheap, and temp insensitive blood testing tech. Graphene based,

http://www.spacedaily.com/reports/Graphene_sheets_capture_cells_efficiently_999.html

"They did this by enzymatically coating the treated graphene oxide surface with peptides called nanobodies - subunits of antibodies, which can be cheaply and easily produced in large quantities in bioreactors and are highly selective for particular biomolecules."

The findings are reported in the journal ACS Nano in a paper co-authored by Neelkanth Bardhan, an MIT postdoc, and Priyank Kumar PhD

Comment author: morganism 17 March 2017 10:56:18PM 0 points [-]

interesting time based economic model for stock market stalls...

http://www.marketwatch.com/story/crash-guru-warns-the-dow-could-plunge-to-14800-and-todays-a-date-to-watch-2017-03-13

"He’s currently on the lookout for the benchmark to approach that upper green line, which represents a range of 21,800 to 22,000. "

“Don’t just go short,” he said. “ That’s where the public gets it all wrong. You have to wait for a break of the low of that weekly bar, and put a stop above the high.”

And here’s the crux of Jadeja’s concerns: If the rally inspired by last year’s presidential election continues, the Dow industrials could hit that 22,000 level — but if it fails, the pullback could be steep, or even steeper, based on history.

One level down would take the DJIA to 18,600, while moving two full levels lower would bring it to the aforementioned 14,800 level.

Comment author: Lumifer 18 March 2017 03:26:59PM 2 points [-]

Rubbish.

Comment author: gjm 18 March 2017 12:35:15PM *  1 point [-]

This sort of technical analysis is usually nonsense. Is there any reason to think this case is better? This person claims a strong track record of predicting market crashes on particular dates. Here's an example from July 2016; he says to look out for trouble in the Dow Jones (1) between 2016-08-26 and 2016-08-30, (2) on 2016-09-26, and (3) on 2016-10-20. No prizes for guessing the outcome: the Dow Jones was just fine on and around all three of those dates.

(That example was the first one I found, by the way. No cherrypicking on my part.)

So I think he's a bullshitter who makes a lot of predictions and then afterwards points to the ones that happened to be somewhere in the vicinity of the truth.

[EDITED to add:]

One reason articles like this call him a "crash guru" is that he allegedly predicted the "flash crash" of August 2015. But let's just look a little more closely at these impressive results (which you can be sure are the ones he quotes to impress journalists):

On July 31, 2015, the chart specialist went on CNBC and warned of a major volatile move to come between Aug. 7 and 18, which turned out to be the so-called “flash crash” of Aug. 24. He also flagged another period to be careful of — Sept. 13 to Sept. 23.

He then went back on CNBC on Aug. 28, 2015, and told viewers there would be a drop on Sept. 14 or 17. A nearly 290-point plunge hit the Dow industrials on Sept. 18; the index proceeded to lose more even ground over several trading days.

Looks good. Until you actually read carefully. This lists three predictions. (1) A major volatile move between the 7th and 18th of August. Allegedly fulfilled by a crash on ... the 24th of August. Nope, sorry, if you quote a particular date range then something happening outside that date range does not count as a correct prediction. (2) A "period to be careful of" between the 13th and 23rd of September. The DJIA was just fine during that period. (3) A drop on the 14th or 17th of September. Allegedly fulfilled by a drop on the 18th. Nope, if you predict specific dates then something on a different date does not count as a correct prediction.

What actually happened: the DJIA was pretty stable through the "major volatile move" period. Then a week later it had a crash which Jadeja didn't predict. Then it was rather volatile for a month or so, a period in which Jadeja mentioned a couple of specific bad dates that were in fact no worse than any others during that volatile period.

So, again, I reckon: bullshitter with no actual predictive ability.

Comment deleted 17 March 2017 06:53:51PM [-]
Comment author: SnowSage4444 17 March 2017 05:50:50PM *  0 points [-]

I've decided I'm going to write... Rational Jojo's Bizarre Adventure.

Comment deleted 17 March 2017 05:36:24PM [-]
Comment author: Viliam 18 March 2017 10:01:01AM 0 points [-]

Mods are sleeping, but when they wake up, they are probably going to delete some of your comments. You had enough time to find the "Reply" button and learn about threads. Please try to keep related comments at one place in the future.

Comment author: Douglas_Knight 18 March 2017 06:06:47PM 0 points [-]

We need more mods in Europe. You used to be a moderator, so why not reclaim that power?

Comment author: Viliam 18 March 2017 06:28:56PM 0 points [-]

I am actually trying (completely unsuccessfully, but there is always hope) to get rid of my Less Wrong addiction. That would be a step backwards.

Comment author: SnowSage4444 17 March 2017 05:36:18PM 0 points [-]

The wiki said I need more karma to post outside of this thread.

Comment author: madhatter 16 March 2017 02:12:55AM 0 points [-]

Is neuroscience research underfunded? If so, I've been thinking more and more that trying to understand human consciousness has a huge expected value, and maybe EA should pay it more attention.

Comment author: MrMind 16 March 2017 08:44:34AM 0 points [-]

understand human consciousness has a huge expected value

Does it? What do you think would be an expected return of the discovery of the precise mechanics of consciousness? Or what if neuroscience dissolves consciousness?

Comment author: madhatter 16 March 2017 11:58:32AM 0 points [-]

Well, suppose it increases awareness of the threat of AGI, if we can prove that consciousness is not some mystical, supernatural phenomenon. Because it would be more clear that intelligence is just about information processing.

Furthermore, the ethical debate about creating artificial consciousness in a computer (mindcrime issues, etc.) would very shortly become a mainstream issue, I would imagine.

Comment author: ingive 17 March 2017 08:44:35AM *  0 points [-]

I'm not sure if intelligence and consciousness are one and the same thing, and with your words, consciousness/intelligence is information processing. If you conclude that intelligence is information processing, then this might be an aspect of the body, an attribute, in roughly the same way as consciousness. Then that aspect of the body is evolving in machines, called artificial intelligence, independent of conscious experience.

Consciousness has such a wide variety of states, whether it be mystical, religious experiences, persistent non-symbolic experiences, nonduality or even ordinary states and so forth. It's fine that these states are seen from the perspective of neurons firing in the brain, but from the state of the beholder, it's well, you know... maybe unsatisfactory to conclude the source is the brain? William A. Richards[1], for example, have the view that the 'hard problem of consciousness' is a philosophical question, and I don't doubt many others who have experienced these states have a more open appreciation for this idea. [4]

But as a philosophical question, even with the assertion that consciousness is information processing, it could be this 'brain being a receiver or reducing valve' philosophical idea. Hence, creating conscious machines means inducing a reduction valve of Mind-At-Large or receiver, however you want to look at it.

Recent neuroimaging studies have sparked the light of Aldous Huxley's philosophical idea[2] that the brain is a reducing valve for Mind-At-Large, consciousness, by showing that reductions in blood flow to certain regions of the brain with for example psychedelics lead to a more intense experience.

"As you can see here, there was a negative correlation between the blood flow to these areas and the intensity of the subjective experience by the subjects, so the lower the blood flow, the more intense the subjective experience. " [3]

Probably the most efficient way to accelerate neuroscience research is with AGI and I wouldn't be surprised if DeepMind's coming AGI will be utilized for this purpose as for example Hassabis is a neuroscientist and been a strong proponent for AGI scientists.

1] [https://www.theguardian.com/books/2015/dec/07/william-a-richards-psychedlics-entheogens-book

2] [https://www.goodreads.com/quotes/327452-aldous-huxley-compared-the-brain-to-a-reducing-valve-in

3] [https://blogs.scientificamerican.com/scicurious-brain/this-is-your-brain-on-psilocybin/

4] [https://www.psychologytoday.com/blog/unique-everybody-else/201604/psychedelic-drugs-and-the-nature-personality-change

Comment author: Sandi 15 March 2017 10:28:23PM *  0 points [-]

I have two straight-forward empirical questions for which I was unable to find a definitive answer.

1) Does ego depletion exist? There was a recent meta-study that found a negligible effect, but the result is disputed.

2) Does visualizing the positive outcome of a endeavor help one achieve it? There are many popular articles confirming this, but I've found no studies in either direction. My prediction is no, it doesn't, since the mind would feel like it already reached the goal after visualizing it, so no action would be taken. It has been like this in my personal experience, although inferring from personal experience is incredibly unreliable.

Comment author: gjm 15 March 2017 11:11:04PM 3 points [-]

On #2, I've seen it claimed -- but have no idea how good the science behind it is -- that better than visualizing positive or negative outcomes alone is doing both and paying attention to the contrast. "If I do X, then the result will look like Y. If I don't do X, the result will look like Z. Wow, Y is much better than Z: better get on with doing X".

Comment author: Unnamed 15 March 2017 11:40:48PM 3 points [-]

The keyword for that research is mental contrasting. It was previously discussed on LW here.

My impression is that the quality of the science is relatively good, compared to other psychology research that was done in 2000-2012. But as far as I know it has not yet been tested with the improved research methods that have come out of the replication crisis (e.g., I don't know of any large sample size, preregistered studies of mental contrasting).

Comment author: Sjcs 16 March 2017 09:00:52AM 0 points [-]

As a bit of a tangent to 2)

Certainly using visualisation as practice has some evidence (especially high-fidelity visualisation increasing performance at comparable rates to actual practice; one course I've been to advocated for the PETLEPP model in the context of medical procedures/simulation) - in this sense it may help achieving an endeavor but 1. It's got nothing (much) to do with positive visualisation and 2. It feels like its moving the goal-posts by interpreting the 'endeavor' as 'performing better'.

I've definitely also heard people discussing positive and negative visualisation as tools for emotional stabilisation and motivation - although the more persuasive (read: not sounding like new age/low brow self help BS) usually favour using both together or just negative visualisation - see gjm's and Unnamed's posts

Comment author: MrMind 16 March 2017 08:50:37AM 0 points [-]

1) We still don't know yet. If we are not observing some statistical noise, then it's possible that it's either bimodal (some have it, some don't) or it has a very weak effect.

2) Visualizing only the positive outcome, as far as I know, doesn't work. There's an interesting book about it: Rethinking positive thinking, by G. Oettingen. I've only skimmed it though, and I don't know how sound are the citations.

Comment author: Elo 16 March 2017 03:14:40AM 0 points [-]
  1. we don't know either way. It seems that believing it exists causes your ego to be depleted though.

  2. it probably relates to the original context in which you do the visualisation. You have given one example of a context where conflicting results might come out, there are several similar situations, so it's hard to know. I would feel safe saying that it seems to work some of the time for some people.

Comment deleted 15 March 2017 02:00:11PM [-]
Comment author: Viliam 17 March 2017 12:03:00PM 2 points [-]

Here are the components of doing everything on your own:

1) You need to acquire the domain; that means, to have it officially recognized that "snowsage4444 . com" legally belongs to you. That costs about 10 dollars a year, and it allows you to create web pages like "snowsage4444 . com / welcome .html" or e-mails like "snowsage4444 @ snowsage4444 . com". What it actually does is that when anyone on the internet says "snowsage4444 . com", they will be redirected to a computer of your choice. But for this all to actually work, you also need...

2) A computer that is connected to internet 24 hours a day, 7 hours a week. That is usually someone else's computer, and they will give you a directors in it, where you can put your pages, pictures, programs, etc. This is called web hosting, and usually also comes with an e-mail service. The costs... can depend a lot, basically on how many gigabytes of space you need, on which programming languages do you want to have installed there, how much are you willing to pay extra for security or reliability, etc. For example, I pay about 100 dollars a year, but it could be much cheaper. (I am a programmer, so I want to experiment there with some things.)

3) Okay, so you have a computer connected to the internet, and whoever types in your e-mail or web address, is sent to that computer. Now, in case of web addresses, what will be waiting for them there? For a passive web site, you can just put there a few text files, and it's done. If you want some interaction, such as posting comments below your articles, you will need a program. There are some free programs available, such as WordPress, but then you have to learn how to use them.

...or you can use an existing service, such as Fanfiction . Net and avoid all these problems. You will have less freedom and flexibility, but those come with a price.

You could also use a less specialized service, for example instead of "something to post fan fiction" you will use "something to post articles", i.e. a generic blogging or CMS software. You may lose some functionality, but gain more choice in the remaining things.

It seems like for you it would be safest to go with "whatever requires least configuration", that is using either Fanfiction . Net or some free blogging platform that is already installed there, where you just need to create an account and start posting.

By the way, you are free to change your mind later, and move the stories to a new place, if you decide so.

Comment author: gjm 15 March 2017 03:48:19PM 2 points [-]

The magic words you are looking for are "web hosting".

Comment author: fubarobfusco 15 March 2017 11:46:27PM 2 points [-]

And "domain registration", which many web hosting providers will do for you. You can also start with the domain and then add services such as web sites and email, for instance via Google Domains:

https://domains.google.com/registrar?s=snowsage

Comment author: Lumifer 15 March 2017 03:31:39PM 0 points [-]

Sacrifice a chicken to the great god Google and pray really really hard.

Comment deleted 15 March 2017 01:59:53PM [-]
Comment author: gjm 15 March 2017 09:24:19PM *  1 point [-]

When you write a comment, like this one, that only makes sense in the context of another -- in this case your earlier question -- you should make your later comment a reply to your earlier one.

More generally, you've posted these questions, all within a few minutes of one another:

  • How do I post a fanfic?
  • Is there a guide on how to write rationalist fanfiction?
  • Am I meant to post my fanfic on fanfiction.net or AO3?
  • Or should I create a new article for it?
  • How do I get my own website?

These really don't need to be separate comments. Better would have been a single comment in the open thread saying something like "I am interested in writing rationalist fanfiction. Has anyone written a guide to doing this? Where should I post it -- on fanfiction.net, AO3, or here, or somewhere else? If I want to put it on my own website, how do I get one?".

Comment author: SnowSage4444 15 March 2017 01:59:43PM 0 points [-]

Am I meant to post my fanfic on Fanfiction.Net or Archive of our own?

Comment deleted 15 March 2017 01:53:58PM [-]
Comment author: fubarobfusco 15 March 2017 11:47:11PM 1 point [-]
Comment author: SnowSage4444 17 March 2017 07:32:38PM 0 points [-]

I read it.

Which is better, rationalreads.com or rationalfiction.io?

Comment author: ingive 14 March 2017 01:11:23AM 0 points [-]

Important insight which LessWrong can comment on: link

To me, it's a very concise summary of what we all know yet stupidly enough, ignore because of irrational societies and educational systems. I'm not saying that I am taking it in. That would be the equal excuse as of any other. What do you think?

Comment author: MrMind 14 March 2017 07:59:43AM *  1 point [-]

My 2 cents: it's a heap of unproved assumptions, told as if they were Reality 101. It's very clear that it was written with an aim in mind, it meanders and misinterprets until it arrives at the desired conclusion. It's very far from an honest discussion of fundamentals.