Rationality Quotes June 2014

It's sort of an odd example, though, since Gladwell himself consistently succeeds.

ETA: Given the downvote, maybe I should clarify that I don't mean that Gladwell succeeds at being the kind of writer that I would want to read. I mean that he consistently succeeds at writing best-selling books. The "igon-value" thing was cringe-inducing, but it plausibly hasn't done any significant harm to his sales. Apparently, you can be careless in that way and still succeed fantastically, again and again, with his target audience.

So, in that sense, he's not a good example for the claim that "people who success many times in the row, tend to employ eigenvalues rather than use igon value." (Though, of course, his existence doesn't disproves the claim, either.)

Let me point out that you can make very straightforward Bayesian estimates of performance/skill/alpha by starting with, say, zero-alpha prior and then updating on monthly returns.

It's good enough.

No, I don't think so.

But all you really need to know is that regardless of how easy or hard it is to guess how a business will do, the market will ensure that you're competing with other people who are really good

This can be applied to anything from looking for a job to dating.

So, no, that's not all you really need to know.

Coincidentally, I was actually heading out to meet my dad (a physics Ph.D.), and I mentioned the paper and blog post to him to get his reaction. He asked me to send him a link, but he also pointed me at Feynman's lecture on electrostatic analogs, which is based on one of those simple ideas that invites bullet-swallowing: The same equations have the same solutions.

This is one of those ideas that I get irrationally excited about, honestly. The first thing I thought of when you described these hydrodynamic experiments was the use of similitude in experimental modeling, which is a special case of the same idea: after you work out the equations that you would need to solve to calculate (for example) the flow of air around a wing, instead of doing a lot of intractable mathematics, you rewrite the equations in terms of dimensionless parameters like the Reynolds number and put a scale model of the wing in a wind tunnel. If you adjust the velocity, pressure, &c. correctly in your scale model, you can make the equations that you would need to solve for the scale model exactly the same as the equations for the full-sized wing ... and so, when you measure a number on the scale model, you can use that number the same way that you would use the solution to your equations, and get the number for the real wing. You can do this because the same equations have the same solutions.

For that matter, one of the stories my dad wrote on his blog about his Ph.D. research mentions a conversation in which another physicist pointed out a possible source of interesting complexity in gravitational waves by metaphor to electromagnetic waves - a metaphor whose validity came from the same equations having the same solutions.

I have to say, though, that my dad does not get excited about this kind of thing, and he explained to me why in a way which parallels Feynman's remark at the end of the lecture: these physical models, these analog computations, are approximate. Feynman talks about these similarities being used to design photomultiplier tubes, but explains - in a lecture delivered before 1964, mind - that "[f]or the most accurate work, it is better to determine the fields by numerical methods, using the large electronic computing machines." And at the end of section 4.7 of the paper you linked to:

From the value of alpha, it seems that the electrostatic force is about two orders of magnitude weaker than the mechanical force between resonant bubbles. This suggests one limitation of the bouncing-droplet experiment as a model of quantum mechanics, namely that spherically-symmetric resonant solutions are not a good model for the electron.

On the basis of these factors, I think I would fully endorse Brady and Anderson's conclusions in the paper: that these experiments have potential as pedagogical tools, illuminating some of the confusing aspects of quantum mechanics - such as the way multiple particles interacting produce a waveform that is nevertheless defined by a single amplitude and phase at every point. By contrast, when the blogger you link to says:

What are the quantum parallels for the effective external forces in these hydrodynamic quantum analogs, i.e. gravity and the vibrations of the table? Not all particles carry electric charge, or weak or color charge. But they are all effected by gravity. Is their a connection here to gravity? Quantum gravity?

...all I can think is, "does this person understand what the word 'analogue' means?" There is no earthy reason to imagine that the force of gravity on the droplet and liquid surface should have anything to do with gravity acting on particles in quantum waveforms. Actually, it's worse than that: we can know that it does not, in the same way that, among simple harmonic oscillators, the gravity force on pendulums has nothing to do with the gravity force on a mass on a spring. They are the same equations, and the equations in the latter case don't have gravity in them ... so whatever work gravity does in the solution of the first equation is work it doesn't do in the solution of the second.

I may be doing the man a gross injustice, but this ain't no way to run a railroad.

Because we've known damn well for decades that it's an incomplete theory! If it cannot be unified with the other best-supported theory in the same domain (General Relativity), then it is incomplete. Period.

We don't actually know that. Weinberg has suggested that GR might be asymptotically safe. Most people seem to think this isn't the case, but no one has been able to show that he is wrong. We can rephrase your argument, and instead of putting weight on theories for which we have no evidence, dump the "built up" probability mass on the idea that the two theories don't actually disagree.

Certainly the amount of "contradiction" between GR and quantum field theories are often overblown. You can, for instance, treat GR as an effective field theory and compute quantum corrections to various things. They are just too small to matter/measure.

...huh.

I have to go, but downvote this comment if I don't reply again in the next five hours. I'll be back.

Edit: Function completed; withdrawing comment.

If considering a new hypothesis fundamentally changes the way you think about priors, and the arguments you used to justify ratios between hypotheses no longer hold, then, yes, you will have to look at the evidence again.

I feel a little odd about calling that process 'updating', since I think it's a little more involved than taking into account a single new piece of evidence.

The first is: does this prompt me to think in a way I did not before? If so, it is not evidence, but it allows you to better way the evidence by providing you with more possibilities.

I think that this would only be true if it prompts you to think in a new and random way. Fiction which prompts you to think in a new but non-random way (that is, all fiction) could very well make it worse. It could very well be that the author selectively prompts you to think only in cases where you got it right without doing the thinking. If so, then this will reduce your chance of getting it right.

For a concrete example, consider a piece of homeopathic fiction which "prompts you to think" about how homeopathy could work. It provides a plausible-sounding explanation, which some people haven't heard of before. That plausible-sounding explanation either is rejected, in which case it has no effect on updating, or accepted, making the reader update in the direction of homeopathy. Since the fiction is written by a homeopath, it wouldn't contain an equally plausible sounding (and perhaps closer to reality) explanation of what's wrong with homeopathy, so it only leads people to update in the wrong direction.

Furthermore, homeopathy is probably more important to homeopaths than it is to non-homeopaths. So not only does reading homeopathic fiction lead you to update in the wrong direction, reading a random selection of fiction does too--the homeopath fiction writers put in stuff that selectively makes you think in the wrong direction, and the non-homeopaths, who don't think homeopathy is important, don't write about it at all and don't make you update in the right direction.

If you are actually offered this bet, you probably should not take it.

When I was a young man about to go out into the world, my father says to me a very valuable thing. He says to me like this... "Son," the old guy says, "I am sorry that I am not able to bank roll you to a very large start, but not having any potatoes which to give you, I am now going to stake you to some very valuable advice. One of these days in your travels, a guy is going to come to you and show you a nice, brand new deck of cards on which (Sky snaps fingers) the seal has not yet been broken. This man is going to offer to bet you that he can make the jack of spades jump out of that deck and squirt cider in your ear. Now son, you do not take this bet, for as sure as you stand there, you are going to wind up with an earful of cider."

• Sky Masterson(Marlon Brando)Guys and Dolls

I shall cheerfully bet at very high odds against this happening the next time I roll a standard die.

I almost said "so shall I, but... " - but then caught myself, because I may very well NOT bet at very high odds against this happening the next time I roll what I perceive to be a standard die.

If I believe my opponent is motivated to cheat, and capable of cheating in a manner that turns "roll a standard die" into "listen to my narrative interpretation of why whatever-just-happened means I won", then I'm apparently willing to take some of the resources I would have otherwise put on that bet, and instead put them on "watch out for signs of cheating and/or malfunctioning dice".

I read him as saying his empire was so powerful he didn't need to care about existing reality or to plan ahead; he could make it up as he went and still expected to succeed no matter what, so he didn't need to judiciously study the existing reality before overwriting it.

We are left to guess what alternative decision procedure the speaker is proposing. eli_sennesh's interpretation is one possibility, do you have another?

I read him as saying that the people he is talking to and about are out of the loop. They write about what the politicians are doing, but only after the fact. The politicians have their own sources of information and people to analyse them, and the public-facing writers have no role in that process.

No need to lynch anyone: after all, Marx didn't feel that capitalists were evil, he felt that they were just doing what the prevailing economic system forced them to do: to squeeze profit out of workers to avoid being outcompeted and driven to bankruptcy by the other capitalists. But (most of them) are not actively evil and don't need to be punished. So you could just let them live but take their stuff, and there does exist wide support for the notion of forcibly taking at least some of people's stuff (via taxation).

What evidence moves you to say that the primary reason for rejection of violent revolution is morality rather than practicality? (And why do you/the majority of people think that violent revolution has to end in lynchings? Is there another widely-held opinion that simply stripping the capitalists of their defining trait - wealth - would be insufficient?)

Well if you ignore all the predictions for what should happen afterwards, the mere idea that it's possible to have a violent revolution that would topple an old authoritarian regime wasn't exactly original to Marx.

I suspect that the root of the problem goes to the fact that the universities are supposed to be both centers of research and teaching institutions.

In my estimation (having worked at several universities of various size and prestige, and more recently having consulted at all sorts of businesses) the problem is a common problem in a lot of American business/government since the 1970s/80s- the rise of professional management.

At large flagship U down the street from my house, professor labor costs have dropped markedly (the trend has been to replace tenure track lines with adjuncts and grad students as well as to increase grant overhead. In the science departments, many professors turn a net profit because grant overhead is larger than their salary costs). Enrollment is way up, tuition is way, way up. A drive to leverage university held patents has created massive profits for the university (with some absurdity along the way- a professor tried to start a company only to get a cease and desist order from a semi-conductor company. The university had sold the rights to his research to the semi-conductor company.)

And yet- the university finds itself on the verge of bankruptcy- why? Because management has exploded. The university now has a fellowship office (staffed entirely by managers who add no direct value), not one, but two bureaucratic offices devoted to education quality (how many people does it take to administer teacher feedback forms? Apparently about 20, of which several make more than 100k a year (roughly 5x an adjunct teaching a full load of 10 courses). Twenty years ago, all of the deans were tenured professors who rotated into the job for a few years, now all but one are outside hires who are deans full time. The last president they hired made an absurd amount of money, and brought with him several subordinates all making 150k+ a year. I often wonder how that negotiation went- "I need not only my salary, but I need these extra people to do the parts of the job I don't like."

The problem is insidious- you hire some managers to deal with work no one wants to do. But then, they start hiring people to deal with work THEY don't want to do, so on and so on. Pretty soon all your recent hires have nothing to do with the core competency of your business and they are eating all your profit from within. Its also damn near impossible to get rid of them, because by this point all the hiring and firing that no one wanted to deal with has become their domain.

Its not just education, I've consulted with companies that have more IT project managers than developers, that spend more money on medical benefits-management then they would have spent if they simply paid every claim that walked through the door,etc.

But it doesn't work well for the delivery of education to the masses.

Maybe not, though I would like to see some statistics on that. My prior on this is that education has probably followed the pattern of pretty much every other good thing in 1st world society: it is decade by decade both better and more widely available than it ever has been before.

If your hunches have a good track record, I think you should explore that and come up with a rational explanation, and make sure it's not just a coincidence.

My explanation is that hunches are based on aggregate data that you are not capable of tracking explicitly.

Additionally, while following your hunches isn't inherently bad, rational people shouldn't be convinced of an argument merely based on somebody else's hunch.

Hunches aren't scientific. They're not good for social things. Anyone can claim to have a hunch. That being said, if you trust someone to be honest, and you know the track record of their hunches, there's no less reason to trust their hunches than your own.

Nobody is suggesting we ignore emotions, merely that we don't let them interfere with rational thought (in practice this is very difficult).

I mean ignore the emotion for the purposes of coming up with a solution.

I don't follow this argument.

Overconfidence bias causes you to take too many risks. Risk aversion causes you to take too few risks. I doubt they counter each other out that well. It's probably for the best to get rid of both. But I'd bet that getting rid of just one of them, causing you to either consistently take too many risks or consistently take too few, would be worse than keeping both of them.

I'm not sure I agree with this, do you think that The Big Bang Theory is based on emotion?

Emotions are more about considering theories than finding them. That being said, you don't come up with theories all at once. Your emotions will be part of how you refine the theories, and they will be involved in training whatever heuristics you use.

You can draw a path from emotion to the people who came up with the Big Bang Theory, but you can do that with things other than emotion as well.

I'm certainly not arguing that rationality is entirely about emotion. Anything with a significant effect on your cognition should be strongly considered for rationality before you reject it.

So you can use emotions to better understand your own goals. But you won't be able to convince people who don't know your emotions that your goals are worth achieving.

This looks like you're talking about terminal values. The utility function is not up for grabs. You can't convince a rational agent that your goals are worth achieving regardless of the method you use. Am I misunderstanding this comment?