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The clocks in Grand Central are off by 1 minute:

But Grand Central, for years now, has relied on a system meant to mitigate, if not prevent, all the crazy. It is this: The times displayed on Grand Central’s departure boards are wrong — by a full minute. This is permanent. It is also purposeful.

The idea is that passengers rushing to catch trains they’re about to miss can actually be dangerous — to themselves, and to each other. So conductors will pull out of the station exactly one minute after their trains’ posted departure times. That minute of extra time won’t be enough to disconcert passengers too much when they compare it to their own watches or smartphones … but it is enough, the thinking goes, to buy late-running train-catchers just that liiiiiitle bit of extra time that will make them calm down a bit. Fast clocks make for slower passengers. “Instead of yelling for customers to hurry up,” the Epoch Times notes, “the conductors instead tell everyone to slow down.”

Not everyone is going to equilibrate, just the regulars.  But that’s exactly what you want.  If you set the clock right then everyone is rushing to the train just when its departing.  If you set the clock 1 minute off and everyone equilibrates then still everyone rushes to the train when its departing.

The system works because some of the people adjust to the clock and others don’t.  So the rush is spread over two minutes rather than one.

Cuckoos lay their eggs in other birds’ nests and when the cuckoo chick is born it kicks all of the eggs out of the nest and monopolizes the care and attention of the cuckolded parent.  Fairy wrens have evidently evolved a countermeasure:

Diane Colombelli-Negrel from Flinders University in Australia has shown that mothers sing a special tune to their eggs before they’ve hatched. This “incubation call” contains a special note that acts like a familial password. The embryonic chicks learn it, and when they hatch, they incorporate it into their begging calls. Horsfield’s bronze-cuckoos lay their eggs too late in the breeding cycle for their chicks to pick up the same notes. They can’t learn the password in time, and their identities can be rumbled.

Which is incredibly cool.  An ingenious solution and a testament to the resourcefulness of the evolutionary invisible hand.  Especially when you notice that the cuckoo chick “is a huge, grey monster that looks completely unlike a warbler chick.”  Apparently evolution favors the complex system of teaching and repeating a singing password rather than the boring solution of just staring at the invader and noticing that he looks nothing like a cute little fairy wren.

I was having coffee outside and I saw ants crawling on my feet so I moved to another table.

Then I rewound my stream of consciousness about 30 seconds and I was able to recall that in fact there was a little more going on than that. I was daydreaming while sipping my coffee and I felt ticklishness on my toes and ankles. That made me look down and that’s when I saw the ants.

Now the fact that I had to rewind to remember all of this says something interesting. Had I looked down and not seen ants, i.e. if it turned out it was just the precious Singapore wind blowing on my cozy bare feet, then this episode would never have penetrated my conscious mind. I would have gone on daydreaming without distraction.

The subconscious mind pays attention to a million things outside of our main line of being and only when it detects something worth paying attention to does it intervene in some way. There are two very common interventions. One is to react at a subconscious level. I.e. shooing a fly while I go on daydreaming. Another is to commandeer consciousness and force a reaction. I.e. pay attention to an attractive potential mate passing by.

Both of these involve the subconscious mind making a decisive call as to what is going on, what is its level of significance, and how to dispense with it. It’s all or nothing: let the conscious mind go on without interruption or completely usurp conscious attention.

But the ant episode exemplifies a third type. My subconscious mind effectively said something like this :”I am not sure what is going on here, but I have a feeling that its something that we need to pay attention to. But to figure that out I need the expertise and private information available only to conscious visual attention and deliberation. I am not telling you what to do because I don’t know, I am just saying you should check this out.”

And so a tiny slice of consciousness gets peeled off to attend to that and only on the basis of what it sees is it decided whether the rest has to be distracted too.

As the director of recruiting for your department you sometimes have to consider Affirmative Action motives.  Indeed you are sympathetic to Affirmative Action yourself and even on your own your recruiting policy would internalize those motives.  But in fact your institution has a policy.  You perceive clear external incentives coming from that policy.

Now this creates a dilemma.  For any activity like this there is some socially optimal level and it combines your own private motivations with any additional external interests.  But the dilemma for you is how these should be combined.  One possibility is that the public motive and your own private interest stem from completely independent reasons.  Then you should just “add together” the weight of the external incentives you feel plus those of your own.  But it could be that what motivates your Dean to institutionalize affirmative action is exactly what motivates you.  In this case he has just codified the incentives you would be responding to anyway,  and rather than adding to them, his external incentives should perfectly crowd out your own.

There is no way of knowing which of these cases, or where in between, the true moral calculation is.  That is a real dilemma, but I want to think of it as a metaphor for the dilemma you face in trying to sort out the competing voices in your own private moral decisions.

Say you have a close friend and you have an opportunity to do something nice for them, say buy them a birthday gift.  You think about how nice your friend has been to you and decide that you should be especially nice back.  But compared to what? Absent that deliberative calculation you would have chosen the default level of generosity.  So what your deliberation has led you to decide is that you should be more generous than the default.

But how do you know?  What exactly determined the default?  One possibility is that the default represents your cumulative wisdom about how nice you should be to other people in general.  Then your reflection on this particular friend’s particular generosity should increment the default by a lot.  But surely that’s not the relevant default.  He’s your friend, he’s not just an arbitrary person (you would even be considering giving a gift to an arbitrary person.)  No doubt your instinctive inclination to be generous to your friend already encodes a lot of the collected memory and past reflection that also went into your most recent conscious deliberation.  And as long as there is any duplication, there should be crowding out. So you optimally moderate the enthusiasm that arises from your conscious calculation.

But how much?  That is a dilemma.

If you take your placebos on time and never miss a “dose” you are less likely to die.

Here’s the big finding: in the placebo group of 1174 patients, the people who took all of their placebo pills on time (the good adherers), were significantly less likely to die than the patients who missed lots of doses. People who took over 75% as directed were 40% less likely to die than those with less than 75% adherence

Neuroskeptic has the story, and it appears not to be simply because healthy people are also more responsible, they controlled for measures of health.

This is something I have wondered about for a long time.

When the muscle is stretched, so is the muscle spindle (see section Proprioceptors). The muscle spindle records the change in length (and how fast) and sends signals to the spine which convey this information. This triggers the stretch reflex (also called themyotatic reflex) which attempts to resist the change in muscle length by causing the stretched muscle to contract. The more sudden the change in muscle length, the stronger the muscle contractions will be (plyometric, or “jump”, training is based on this fact). This basic function of the muscle spindle helps to maintain muscle tone and to protect the body from injury.

One of the reasons for holding a stretch for a prolonged period of time is that as you hold the muscle in a stretched position, the muscle spindle habituates (becomes accustomed to the new length) and reduces its signaling. Gradually, you can train your stretch receptors to allow greater lengthening of the muscles.

Some sources suggest that with extensive training, the stretch reflex of certain muscles can be controlled so that there is little or no reflex contraction in response to a sudden stretch. While this type of control provides the opportunity for the greatest gains in flexibility, it also provides the greatest risk of injury if used improperly. Only consummate professional athletes and dancers at the top of their sport (or art) are believed to actually possess this level of muscular control.

This clarified a lot for me.

Suppose our minds have a hot state and a cool state.  In the cool state we are rational and make calculated tradeoffs between immediate rewards and payoffs that require investment of time and effort.  But when the hot state takes over we abandon deliberation and just react on instinct.

The hot state is there because there are circumstances where the stakes are too high and our calculations too slow or imperfect.  You are being attacked, the food in front of you smells funky, that bridge looks unstable.  No matter how confident your cool head might be, the hot state grabs the wheel and forces you to do the safe thing.

Suppose all of that is true.  What does that mean when a situation looks borderline and you see that instincts haven’t taken over?  Your cool, calculating head rationally infers that this must be a safer situation than it would otherwise appear.  And you are therefore inclined to take more risks.

But then the hot state better step in on those borderline situations to stop you from taking those excessive risks.  Except that now the borderline has moved a little bit toward the safe end.  Now when the hot state doesn’t take over it means its even more safe, etc.

And of course there is the mirror image of this problem where the hot state takes over to make sure you take an urgent risk.  A potential mate is in front of you but the encounter has questionable implications for the future.  Physical attraction receives a multiplier.  If it is not overwhelming then all of the warning signs are magnified.

Here’s what you already know:  it’s a parasite that reproduces in the digestive system of cats.  The eggs are excreted out and the vehicle is consumed by other animals in whose brains the eggs develop. Only when those brains are consumed by other cats does the cycle continue.  In order to facilitate this process, chemicals are secreted inside the hosts’ brain to make them do things to increase the chance they will be eaten by cats.  For example, rats with toxoplasma in their brains are not afraid of cats.

Here’s what’s new:  toxoplasma is transferred from host to host through sexual contact in order to get closer to cats.

These are Toxoplasma cysts moving from rat to rat, so this exchange is kind of like a side track on the parasite’s life cycle. But it still benefits Toxoplasma, because it means it can infect even more potential prey that may get eaten by cats. And so the logic applies once more: if Toxoplasma can raise the odds of getting from infected males to uninfected females, it may have more reproductive success.

You know where this is going–it’s turning into a David Cronenberg horror movie with an all-rodent cast. Vyas wondered if there’s any difference in how female rats mate with infected and uninfected males. So he and his colleagues put a male rat with Toxoplasma at one end of a two-armed maze, and an uninfected male in the other arm. Females then got to choose which rat to approach. Vyans found that they preferred the infected males, spending more time with them and mating more often.

Tyler Cowen quotes Richard Dawkins:

Isn’t it plausible that a clever species such as our own might need less pain, precisely because we are capable of intelligently working out what is good for us, and what damaging events we should avoid? Isn’t it plausible that an unintelligent species might need a massive wallop of pain, to drive home a lesson that we can learn with less powerful inducement?

There is an alternative to pain as an incentive mechanism:  dispensing with incentives altogether and just programming the organism with instructions to follow. And if the organism doesn’t already have “feelings” as a part of its infrastructure then the instructions are the only alternative.  The big question for theories of pain and pleasure as an incentive mechanism is why mother nature as Principal bothers with incentives at all.

Emperor penguins form a group huddle to share warmth as they wait for eggs to hatch.  How do they coordinate?

Emperor penguins are the only vertebrates that breed during the austral winter where they have to endure temperatures below −45°C and winds of up to 50 m/s while fasting. From their arrival at the colony until the eggs hatch and the return of their mates, the males, who solely incubate the eggs, fast for about 110–120 days [1][3]. To conserve energy and to maintain their body temperature[4], the penguins aggregate in huddles where ambient temperatures are above 0°C and can reach up to 37°C [1][3].

Huddling poses an interesting physical problem. If the huddle density is too low, the penguins lose too much energy. If the huddle density is too high, internal rearrangement becomes impossible, and peripheral penguins are prevented to reach the warmer huddle center. This problem is reminiscent of colloidal jamming during a fluid-to-solid transition [5]. In this paper we show that Emperor penguins prevent jamming by a recurring short-term coordination of their movements.

What are the individual incentives in the huddle?  It would seem that the dynamics would be governed by the need to prevent manipulation by a self-interested penguin.

Check out this video (unfortunately you have to click to download it, its about 30MB.  there is no streaming version.)

That was the title of a very interesting talk at the Biology and Economics conference I attended over the weekend at USC.  The authors are Juan Carillo, Isabelle Brocas and Ricardo Alonso.  It’s basically a model of how multitasking is accomplished when different modules in the brain are responsible for specialized tasks and those modules require scarce resources like oxygen in order to do their job.  (I cannot find a copy of the paper online.)

The brain is modeled as a kludgy organization.  Imagine that the listening-to-your-wife division and the watching-the-French-Open division of YourBrainINC operate independently of one another and care about nothing but completing their individual tasks.  What happens when both tasks are presented at the same time? In the model there is a central administrator in charge of deciding how to ration energy between the two divisions.  What makes this non-trivial is that only the individual divisions know how much juice they are going to need based on the level of difficulty of this particular instance of the task.

Here’s the key perspective of the model.  It is assumed that the divisions are greedy:  they want all the resources they need to accomplish their task and only the central administrator internalizes the tradeoffs across the two tasks.  This friction imposes limits on efficient resource allocation.  And these limits can be understood via a mechanism design problem which is novel in that there are no monetary transfers available.  (If only the brain had currency.)

The optimal scheme has a quota structure which has some rigidity.  There is a cap on the amount of resources a given division can utilize and that cap is determined solely by the needs of the other division.  (This is a familiar theme from economic incentive mechanisms.)  An implication is that there is too little flexibility in re-allocating resources to difficult tasks.  Holding fixed the difficulty of task A, as the difficulty of task B increases, eventually the cap binds.  The easy task is still accomplished perfectly but errors start to creep in on the difficult task.

(Drawing:  Our team is non-hierarchical from www.f1me.net)

As I was walking toward my locker at the gym I checked my pocket for the little card with the locker combination written on it.  It wasn’t there.  In a panic I tried to recall the combination.  It was just 30 minutes ago that I had that combination in my head.  But I couldn’t remember it.  So I searched all of my pockets and finally felt the card in my back pocket.  Panic over, I left the card in my pocket and kept walking, my mind quickly wandering to some random topic.

When I reached the locker, without thinking I opened it from memory without looking at the card.

I often have that sense that trying too hard makes it hard to remember something.  There is even a physical feeling that comes with it.  It’s like the brain seizes up and gets locked into a certain part of memory storage with no way of retracing steps back to neutral and starting the search over.  After enough experience with this I sometimes notice the potential for panic before starting to search intensively for a memory that feels like its going to be hard to find.  You have to pretend like you don’t really have something to remember.  And most of all you have to make sure not to think of the thing that you are trying to remember because you know that if you do, the search will start by itself and get stuck.  If you can do a little Zen breathing for a minute and let that feeling pass over, then you can safely start to think about it and recover the memory with ease.

At least that’s how I imagine it would work.

Apart from a certain solitary activity, all other sensations caused by our own action are filtered out or muted by the brain so that we can focus on external stimuli.  There is a famous experiment which demonstrates an unintended consequence of this otherwise useful system.

You and I stand before each other with hands extended.  We are going to take turns pressing a finger onto the other’s palm.  Each of us has been secretly instructed to each time try and match the force the other has applied in the previous turn.

But what actually happens is that we press down on each other progressively harder and harder at every turn. And at the end of the experiment each of us reports that we were following instructions and it was the other that was escalating the pressure.  Indeed, the subjects in these experiments were asked to guess the instructions given to their counterpart and they guessed that the others were instructed to double the pressure.

What’s happening is that the brain magnifies the sensastion caused by the other’s pressing and mutes the sensation caused by our own.  Thus, each of us underestimates the pressure when it is caused by our own action.  (In a control experiment the force was mediated by a mechanical device –and not the finger directly– and there was no escalation.)  So each subject believes he is following the instructions but in fact each is contributing equally to the escalating pressure.

You are invited to extrapolate this idea to all kinds of social interaction where you are being perfectly polite, reasonable, and accomodating, but he is being insensitive, abrasive, and stubborn.

Native English speakers never have difficulty learning which prepositions to use.  On the other hand I often hear even quite fluent second-languagers stumble over things like “Independent from, er… independent of.” (As in, X is independent of Y.) Is this just because children are better at learning language than adults?  That probably explains a lot.  But as I have speculated before I think there are some aspects of the difference between adults and children that don’t require an appeal to brain differences.

Adults are building on stuff they already know, children are learning for the first time.  Adults know what a preposition is and that “from” and “of” are both prepositions.  They know grammar and they think in terms of grammatical structure.  So they search through the prepositions they know that would play the right grammatical role.

Children don’t think about language, they just copy what they hear.  They don’t hear “independent from” so they never consider saying that.  Of course adults learning English don’t hear “independent from” either.  The fact that they still make the mistake means that they don’t learn purely by imitation like children.  They make use of the rules they already know.

And yes, I am just making this up. Claire?

Female digger wasps prey on katydids.  But they don’t kill them.  They paralyze them and then store them in little holes they dig in the ground.  They are preparing nests where they will lay eggs and when the eggs hatch, the larvae will feast on the katydids.

Richard Dawkins and John Brockman observed that it sometimes happens that two digger wasps are unknowingly tending the same nest.  Naturally, once they figure this out, there’s going to be a fight.  Dawkins and Brockman noticed two things about these fights.  First, the wasp that wins is usually the one that has contributed more katydids to the common nest.  Second, the duration of the fight is predicted by the number of katydids contributed by the eventual loser.

For Dawkins and Brockman the wasps are revealing a sunk-cost fallacy.  Evidently, their willingness to fight is not determined by the total reward, but instead by the individual wasp’s past investment.  The more they invested, the more they are willing to fight.

A more nuanced interpretation is that the wasps’ behavior is not a fallacy at all, but a clever hack.  The wasps really do care about the total value of the nest, but their best estimate of that value is (proportional to) their own contribution to it.  For example, a wasps may be able to “remember” the number of katydids she paralyzed (and she must if she is able to condition her fighting intensity on that number) but not be able to count the number of katydids in the nest.  The former is going to be correlated with the latter.

Sunk cost bias:  a handy trick.

Emotions are Nature’s incentive schemes getting us to do what’s in our evolutionary interest.  But unlike the textbook principal-agent relationship, there is no intrinsic conflict of interest.  The principal gets to design the agent, essentially dictating the terms of the contract. However, in practice the contract is incomplete.  Instead of being programmed with an exhaustive set of instructions for every contingency we are designed to respond to emotions.

This second-best solution has its costs.  For example, fear can kill you.  In fact, your enemies can scare you to death.

From Not Exactly Rocket Science:

In the Old English of Beowulf, seven different rules competed for governance of English verbs, and only about 75% followed the “-ed” rule. As the centuries ticked by, the irregular verbs became fewer and far between. With new additions to the lexicon taking on the standard regular form (‘googled’ and ‘emailed’), the irregulars face massive pressure to regularise and conform.

Today, less than 3% of verbs are irregular but they wield a disproportionate power. The ten most commonly used English verbs – be, have, do, go say, can, will, see, take and get – are all irregular. Lieberman found that this is because irregular verbs are weeded out much more slowly if they are commonly used.

To get by, speakers have to use common verbs correctly. More obscure irregular verbs, however, are less readily learned and more easily forgotten, and their misuse is less frequently corrected. That creates a situation where ‘mutant’ versions that obey the regular “-ed” rule can creep in and start taking over.

That seems to be the thesis of this paper by neurobiologist Jerome Siegel:

Sleep can be seen as an adaptive state that benefits animals by increasing the efficiency of their activity. It does this by suppressing activity at times that have maximal predator risk and minimal opportunity for efficiently meeting vital needs, and by permitting activity at times of maximal food and prey availability and minimal predator risk.

I read this as arguing that if an animal is not sleeping it will do things that are not in its interest.  So sleep stops it from doing those things. Of course natural selection could instead have simply taught the animal not to do what’s against its self interest but instead, under this theory, sleep acts like a commitment device to blunt a self-control problem.

Via neuroskeptic.

Mindhacks has the scoop:

…in summary it seems that the brain simulates of the outcomes of actions based on your intentions to move because the actual sensory information from the body takes so long to arrive that we’d be dangerously slow if we relied only on this.This slower information is used for periodic updates to keep everything grounded in reality, but it looks like most of our action is run off the simulation.

We can also use the simulation to distinguish between movements we cause ourselves and movements caused by other things, on the basis that if we are causing the movement, the prediction is going to be much more accurate.

If the prediction is accurate, the brain reduces the intensity of the sensations arising from the movement – for good safety reasons, perhaps – we want to be more aware of contact from other things than touches from ourselves.

Via BoingBoing, here is a lovely list of kludges under the heading of “worst evolutionary designs.”  My favorite

6 Shark-fetus teeth. A few shark species have live births (instead of laying eggs). The Jaws juniors grow teeth in the womb. The first sibling or two to mature sometimes eat their siblings in utero. Mmm … siblings.

I mention viviparous sharks in my paper “Kludged” becuase most sharks lay eggs and requires a large and coordinated mutation to switch to live birth without producing a fatal misfit.  This example shows that whatever doesn’t kill it only makes it more kludgey.

I collect kludges.  Its an especially welcome addition to the collection when it involves a tasty snack:

DunceCap Doff:  There I Fixed It.

Psyblog has a rundown of 18 failures of the brain’s system of attention.  My favorite:

9. Ironic processes of control

In fact sometimes attention is a real bear. What about when you really want to get something right, like putt the ball, hit a beautiful serve right in the corner or reverse the car into a narrow space? Naturally you concentrate even harder than normal, really focus. Unfortunately that just seems to make things worse: you miss the putt by a mile, frame the ball 50ft in the air and ding the car. What gives? These are what Wegner et al. (1998) call ‘ironic processes of control’. Sometimes too much attention is just as detrimental as too little.

I normaly strive to pay as little attention as possible.

Start your QJE clocks!  I just submitted my paper Kludged (rhymes with Qjed) to the Quarterly Journal of Economics.  The QJE has a reputation for speedy rejections.  For me this is a virtue.  Obviously I prefer not to be rejected, (although for some a QJE rejection is a well-earned badge of honor) but conditional on being rejected (always the most likely outcome), the sooner the better.

Addendum: Alas, the paper was rejected :(  It took about 3 1/2 months and I received 4 thoughtful referee reports.  All in all I would say I was treated fairly.

I collect examples of KludgesLuis Rayo has sent me a very nice one.

In mammals, for instance, the recurrent laryngeal nerve does not go directly from the cranium to the larynx, the way any competent engineer would have arranged it. Instead, it extends down the neck to the chest, loops around a lung ligament and then runs back up the neck to the larynx. In a giraffe, that means a 20-foot length of nerve where 1 foot would have done. If this is evidence of design, it would seem to be of the unintelligent variety.

Apparently, some evolutionary biologists take this to be evidence of our fish ancestry.

“The circuitous path of the left recurrent laryngeal nerve in humans is evidence for their evolution from a fishlike ancestor… because the nerve remained behind this arch but still connected to a structure on the neck, it was forced to evolve a pathway that travels down to the chest, loops around the aorta and the remnants of the sixth aortic arch, and then travels back up to the larynx. The indirect path does not reflect intelligent design but can be understood only as the product of our evolution from ancestors having very different bodies.”

The latter quote is from “Why Evolution is True” by Jerry A. Coyne.

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