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Why Transitivity Violations Can Be Rational
ananyo writes "Organisms, including humans, are often assumed to be hard-wired by evolution to try to make optimal decisions, to the best of their knowledge. Ranking choices consistently — for example, in selecting food sources — would seem to be one aspect of such rationality. If A is preferred over B, and B over C, then surely A should be selected when the options are just A and C? This seemingly logical ordering of preferences is called transitivity. Furthermore, if A is preferred when both B and C are available, then A should 'rationally' remain the first choice when only A and B are at hand ... But sometimes animals do not display such logic. For example, honeybees and gray jays have been seen to violate the Independence of Irrational Alternatives, and so have hummingbirds ... Researchers have now used a theoretical model to show that, in fact, violations of transitivity can sometimes be the best choice (original paper) for the given situation, and therefore rational. The key is that the various choices might appear or disappear in the future. Then the decision becomes more complicated than a simple, fixed ranking of preferences. So while these choices look irrational, they aren't necessarily."
It might also have to do with competition. If there's little competition for my preferred food source, I will eat it last, knowing it will last longer. My wife hates dark chocolate, but I prefer it, so if there's a bag of chocolate bars and dark chocolate, I'll dig into the milk chocolate first, knowing that my wife will actively consume those as well, then when they're gone, I still have the dark chocolate to enjoy afterwards, while she's without.
http://www.beanleafpress.com
What about humans have we seen to suggest humans are rational or are hard-wired make 'optimal' choices?
For biologists (or economists) to make this assumption has always struck me as terribly flawed, because in the real world, we see quite the opposite.
In the case of humans, cultural biases and any number of things skew our decision making to be less than perfect. And any theoretical model which assumes otherwise is pretty much the equivalent of assuming a perfectly spherical cow.
Lost at C:>. Found at C.
In fact it is the opposite - scientists previously didn't understand the criteria, and now they think that they do. It is progress in our understanding of the natural world.
W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
And here we have someone whose biases are based entirely in the null hypothesis, using the null hypothesis to justify ignoring the conclusion. It's a good chance to see this behavior outside of its normal habitat of politics/religion.
If your wife reads Slashdot this little game could end quite badly... never get between a woman and her chocolate!
Yes, this is the point of the article. Your ability to look into the future may make you change your current preferences. You know the dark chocolate won't run out, so to maximize your chocolate intake, you eat the milk chocolate first. If your wife were visiting her sister for an extended period of time, you'd probably eat the dark chocolate first, because you like it better.
This is, of course, not nice (wife "I bought the dark for you and the milk for me"), but is probably rational.
Might as well face it I'm addicted to data.
My wife hates dark chocolate, but I prefer it, so if there's a bag of chocolate bars and dark chocolate, I'll dig into the milk chocolate first, knowing that my wife will actively consume those as well, then when they're gone, I still have the dark chocolate to enjoy afterwards, while she's without.
So, you purposefully over indulge, pigging out on the thing your wife likes to intentionally deprive here, meanwhile stashing back stuff you know she won't eat?
I do not expect your marriage is going to last all that long...
An enigma, wrapped in a riddle, shrouded in bacon and cheese
One of my pet peeves with discussions on evolution is the assumption, in general, that any given trait or behavior evolved for a particular reason, or that any one concept such as "logical rationality" can explain the whole evolution of a single such trait. In fact this sounds more like intelligent design than evolution. It's an interesting exercise to track a trait through evolution, but there's a fine line between that and presupposing that every behavior must occur due to some underlying logic.
We're talking about behavior that evolved due to an absurd amount of chaos; how was it not obvious that a "decision becomes more complicated than a simple, fixed ranking of preferences"? And who gets to decide what's "rational"... from a basic evolutionary perspective, anything that has evolved to this point and is still alive and kicking is doing well; it's almost impossible to call any such evolution "irrational", so finding ways to prove it so is just silly. I mean, there's plenty of evolution that seems odd... flightless birds, blind species with eyes, animals that eat their young and their mates... but these species all survive and procreate and carry on from one generation to the next. Why does everything have to be nice and tidy... what's the obsession with "rational"? In fact, the behavior described in the article sounds more rational than the opposite... consider Pandas, who exist almost entirely on one food (bamboo)... these animals are very nearly extinct due to this behavior (some people assert that they would be if it weren't for human efforts to save them). Is that rational from an evolutionary perspective?
I'm sure I sound annoyed, but some times we try to oversimplify things way too much. happy_place is correct; competition could matter, and individual preference clearly exists all over the place... why does there have to be a rationalization? Is it an evolutionary benefit that happy_place likes dark chocolate while their wife hates it? More likely it's just a quirk of evolution, not a grand result of evolution having evolved precisely so that our species won't starve when cocoa is the last remaining food on the planet.
Let me put it this way... given whole of evolution, I would wager that for any categorization of traits that are well defined (such as "rational"), there exists at least one example that is both in and out of that category. SOMETHING has evolved irrationally, oddly, stupidly, and without purpose, due only to quirks of evolution that didn't really get in the way of a species survival, but didn't necessarily help it along either.
If you're trying to find a balanced diet using many ingredients and take one of those away, the rest of the diet might change totally. For example, let's assume the removed ingredient was a very good source of protein. Now you're scrambling to replace it with other protein sources, introducing foods you didn't need before. And now you're high on carbs, so your high-carb food goes out and is replaced by something else, so now you lack vitamin D so we add another new food and so on. It's a set ordering not a factor ordering because if you've eaten beef all week you'd rather eat pork, even if you prefer beef.
Live today, because you never know what tomorrow brings
You obviously know nothing about women.
My wife loves chocolate as well, but hates to eat it because she likes being skinny more than she likes eating chocolate (and if you ask any woman, the two are mutually exclusive). So, if I have chocolate in the house, I must compete with her and ensure that I eat most of it, otherwise she gets upset.
Stereotypes generally have a damned good reason to be stereotypes. Getting called misogynistic or not, if it's true of a significant enough subsample of the population, it can and should be used.
Violence is like duct tape. If it doesn't solve the problem, you didn't use enough.
C'mon that was obviously a joke... How cranky can one be?
You might be surprised - I once knew a lesbian femi-nazi who could, somehow, find offense in you hugging someone, assuming you have a penis.
Welcome to 'Murica, Land of the Cranks, Home of the Narcissistic.
An enigma, wrapped in a riddle, shrouded in bacon and cheese
You are the most knee-jerk racist hiding in a "liberal" sheep's coat that I've ever read comment here.
Do you not realize that in saying things like "femi-nazi," you are one of the cranks you deride?
Unpredictability is a necessary trait when evading predators, so an organism that always chose C when C > B and B > A would be more predictable and easier for an intelligent predator to catch. This tendency not to would need to be deeply hardwired into the nature of the organism, since otherwise it would rarely kick in and, again, the organism would be easy prey. Optimising a small subset of a problem (and the whole problem is survival and procreation) often leads to locally optimal yet seriously globally subobtimal solutions. The greedy algorithm works on only a few cases (sometimes called monoids if I remember my combinatorial optimisation text, though that was over a decade ago); and with only slightly more complex problems it is often easy to construct pathological cases where the greedy algorithm gets it wrong. I see this result about organisms as another example of the principle that straightforward rational solutions are only the best when the problem is straightforward and simple.
John_Chalisque
There is great value in looking at behavior that appears to be irrational and trying to figure out what unconsidered factor makes it rational after all.
For example, the pandas. It may be that their dietary choice is a problem for them now, but prior to the dominance of another species that can and will slash and burn a whole forest, if you're going to depend on a single food, one that grows so fast you can sometimes actually see it growing isn't a bad choice.
Similarly, the potato monoculture decision in Ireland wasn't irrational, it was just made before some very important factors were known.
They are using the word "rational" to describe a specific, common-sense-to-humans, transitive property of preferences. That is all. You are reading way to much into their choice of words. The whole point of evolution by natural selection is that certain traits emerge because they are adaptive. What this paper sets out to show is that the behavior we see is not "rational" in the common sense, but it is still adaptive. It did not evolve "due to an absurd amount of chaos." They're basically arguing that long-term adaptivity trumps short-term logic.
Really there's a pretty good allegory to human behavior here. People frequently prefer to do things that are not in their long-term best interest, because they only think about their short-term best interest. Eating your second-favorite chocolate first could lead to your wife only buying milk chocolate, since you obviously like it better. Shooting the guy in the row in front of you might seem like a good way to get him to stop texting, but it's a terrible way to enjoy the rest of your movie. Faking being in the CIA might sound like a great way to get a nice paid vacation, but you will eventually get busted. Groups of people (think governments) are particularly bad at this, too. If I list any examples, I'll get modded as flamebait, but I'm sure you can think of several.
You know, I never liked the fried chicken or watermelon stereotypes. Who the hell doesn't like fried chicken or watermelon?
Anyway, stereotypes exist because someone observed that, on average, foo is true of a significant portion of demographic bar. They simplify decision making at the expense of some accuracy.
Like many things, there are times when stereotypes are useful and times when using them is a dick move. Recognizing that a fair majority of women like flowers and chocolate is generally fine to both use and say. Recognizing that a good percentage of pregnant women are often freaking insane is impolite to say but you'd damned well better be prepared to deal with it if you're married to one.
Recognizing that most anyone replying like you did is a self-hating lib who cares about feelings more than truth and logic, that one's just too easy.
Violence is like duct tape. If it doesn't solve the problem, you didn't use enough.