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There are now going to be ten nominees for the best picture category. This poses a danger with choosing the film that gets the most votes as the “best picture”: what if it is the worst film according to people who put other movies at the top? Maybe they all agree on the second-best movie and if you take this into account, you’d have a quite different “best picture” winner. To take this kind of thing into account, the Academy of Motion Pictures has come up with a new scheme:
Voters will be asked to rank the 10 best picture nominees in order of preference, one through 10. Davis says that the category will be listed on a special section of the Oscar ballot, detachable from the rest so that a separate team of PricewaterhouseCoopers staffers can undertake the more complicated tabulation process.
Initially, PwC will separate the ballots into 10 stacks, based on the top choice on each voter’s ballot. If one nominee has more than 50 percent of the vote (unlikely, but conceivable some years), we have a winner.
But if no film has a majority, then the film ranked first on the fewest number of ballots will be eliminated. Its ballots will then be redistributed into the remaining piles, based on whichever film is ranked second on those ballots.
If those second-place votes are enough to push one of the other nominees over the 50 percent threshold, the count ends. If not, the smallest of the nine remaining piles is likewise redistributed. Then the smallest of the eight piles, then the smallest of the seven…
Eventually, one film will wind up with more than 50 percent.
Which is the voting system that is more manipulable via strategic voting, the original one or the new one? How is it manipulable? Harvey Weinstein will be willing to pay for advice.
Update: As Mallesh says below and David Austen-Smith pointed out to me in an email, this voting system is the Single Transferable Vote system. It violates Arrow’s independence of irrelevant alternatives and is manipulable as the Gibbard-Satterthwaite Theorem applies when IIA fails. I guess manipulability per se is not the right criterion. One should study the (Bayesian?) Nash equilibria of the voting system in question and compare them via some notion of welfare to the equilibria of the original system. The original system (as far as I can tell – I am not an Oscar voter), was simply one man-one vote with the movie getting the most votes picked as the winner. The new system is much more complicated as you have to report a whole ranking.
After a day of conference talks, but before drinks arrive, game theorists have been known to debate whether what is known as Zermelo’s theorem was actually proved by Zermelo. Eran Shmaya (who is always fun to talk to with or without drinks) decided to go and look at the paper (recently translated) and all but strips Zermelo of his theorem.
So, Zermelo clearly did not set out to prove his eponymous theorem. But was he aware of it ? I guess the answer depends on what you mean by being aware of a mathematical statement (were you aware of the fact that any even number greater than 2 can be written as a sum of a prime number and an even number before you read this sentence ?). But I do believe that some of the logical implications in Zermelo’s paper only make sense if you already assume his theorem.
Suppose two crossword puzzle compilers start with the same key word.
1. The word has to be divided and embedded into phrases.
2. Puzzle designers share the same sense of “taste”: It is considered elegant to divide the key word into as many separate words as possible.
3. Puzzles have to have a certain shape (“180 degree rotational symmetry”).
So, if two or three puzzle designers start off with the same keyword they are highly likely to come up with very similar crosswords as there are only so many solutions given the constraints.
Interestingly, while same problem can occur in economics research, I believe it is less likely than in design of crossword puzzles. For example, I attended at NBER conference on relational contracting. This area of contract theory studies how incentives between a firm and its supplier might be aligned as they interact repeatedly (eg early “cheating” might be punished by a worsening of the relationship later on).
Many researchers at the conference had the same motivation: Why does Toyota deal with a core group of suppliers while GM acquires parts via competitive bidding? So, there are two constraints: same motivation and same theoretical approach (ie relational contracting). And yet the papers were quite different.
The universe of potential models is infinite, unlike natural language, and hence accidental and near identical replication is less likely. To enjoy the infinite, the human brain must know no bounds. Some say this is the case though their claims are controversial.
(Hat tip: Matt Gaffney at Slate)
Via kottke, Clusterflock gives five simple rules for effective bidding on eBay:
Step One:Find the product you want.
Step Two:
Save the product to your watch list.
Step Three:
Wait.
Step Four:
Just before the item ends, enter the maximum amount you are willing to pay for the item.
Step Five:
Click submit.
This is called sniping. That’s a pejorative label for what is actually a sensible and perfectly straightforward way to bid. eBay is essentially an open second-price auction and sniping is a way to submit a “sealed” bid. It’s a popular strategy and advocated by many eBay “experts.” But does it really pay off?
Tanjim Hossain and I did an experiment (ungated version.) We compared sniping to another straightforward strategy we call squatting. As the name suggests, squatting means bidding your value on an object at the very first opportunity, essentially staking a claim on that object. We bid on DVDs and randomly divided auctions into two groups, sniping on the auctions in the first group and squatting on the other.
The two strategies were almost indistinguishable in terms of their payoff. But for an interesting reason. A lot of eBay bidders use a strategy of incremental bidding. That’s where you act as if you are involved in an ascending auction (like an English auction) and you bid the minimum amount needed to become the high biddder. Once you are the high bidder you stop there and wait to see if you are outbid, then you raise your bid again. You do this until either you win or the price goes above the maximum amount you are willing to pay.
Against incremental bidders, sniping has a benefit and a cost (relative to squatting.) You benefit when incremental bidders stop at a price below their value. You swoop in at the end, the incremental bidders have no time to respond, and you win at the low price.
The cost has to do with competition across auctions for similar objects. If I squat on auction A and you are sniping in auction B, our opponents think there is one fewer competitor in auction B and more opponents enter auction B than A. This tends to raise the price in your auction relative to mine. In other words, squatting scares opponents away, sniping does not.
We found that these two effects almost exactly canceled each other out for auctions of DVDs. We expect that this would be true for similar objects that are homogeneous and sold in many simultaneous auctions. So the next time you are bidding in such an auction, don’t think too hard and just bid your value.
Now, I am still trying to figure out what I am going to do with all these copies of 50 First Dates we won in the experiment.
Steven Landsburg set 10 questions for honors graduates at Oberlin College. #8 is a great undergraduate game theory exercise:
Question 8. The five Dukes of Earl are scheduled to arrive at the royal palace on each of the first five days of May. Duke One is scheduled to arrive on the first day of May, Duke Two on the second, etc. Each Duke, upon arrival, can either kill the king or support the king. If he kills the king, he takes the king’s place, becomes the new king, and awaits the next Duke’s arrival. If he supports the king, all subsequent Dukes cancel their visits. A Duke’s first priority is to remain alive, and his second priority is to become king. Who is king on May 6?
visor volley: BoingBoing.
Chris Blattman writes:
Strategy part 3: Figure out the national bargaining fraction. Anchor too low and some cabbies will simply stop talking to you. Unfortunately, that fraction is hard to predict. In Ethiopia, it seems to be about 70%. He’ll counter with 130% the target, and you get to the price you want in about two rounds. Very civilized. This, of course, is based on a sample of four. But my standard error is very low.
I especially love discovering the bargaining fraction and number of rounds in a country. Within a city it is surprisingly consistent, from taxis to markets. Cross-country variation is huge.
Based on travel this year, here is my guesstimation of starting fraction and rounds:
- Ethiopia: 0.7 with 2 rounds
- Argentina: no less than 0.9 and 1 round.
- Canada: 1 and 0
- Uganda: 0.5 and 4 rounds
- Liberia: 0.1 and 8 rounds
- Morocco: 0.001 and upwards of 754 rounds (including mint tea).
I don’t do that much exotic international travel, but I do recall in Singapore that there was no negotiation at all but still it was impossible to know what the fare was because the meter was programmed with all kinds of fixed charges, surcharges and variable mileage rates depending on time of day. Plus major roads have tolls that are adjusted every second depending on traffic and the risk was born by the passengers. So I would call Singapore a 1, -1. (It was always dirt cheap in the end anyway.)
I am a lousy mathematician. I can’t do algebra. My eyes glaze over when asked to follow calculations on the board. And I have a really bad memory. These are just a few of my keys to success.
Because I have minimal facility with technical arguments I had to learn early on how to translate them into natural language so that I could understand them. It takes a long time. And quite often its just impossible to do. In those cases I have to give up.
But when it works, I come away with a unique way of explaining things that are otherwise “left to the appendix.” It makes for good seminars. And it makes teaching time consuming but fun.
Best of all is that enough practice with this and it begins to pay off in research. I can’t “figure things out” with a pen and pad in front of me. Instead I start with an intuition, explain it to myself in a natural language, and see where that goes. Progress usually means formalizing the intuition, seeing some implications on paper, and then retranslating those back, etc. (It helps when I have the talented co-authors I work with.)
I count this liability as a virtue because a) I have to find something to say I am good at, b) being able to explain things in plain language is a valuable skill which I am forced to acquire and c) I’d like to think that it acts as a mild fiddle-filter. If I try hard and I can’t explain it convincingly it words, I am content to say that it must not be a compelling idea. (Not to say that silly ideas don’t nevertheless sometimes slip through the filter.)
1. Ahmad Jamal Trio at the Newport Jazz Festival 1959. I love every version I’ve ever heard of Poinciana.
2. Newton’s letter describing his theory of light, diagrams from his optics book..and much more amazing stuff.
3. Lego version of Matrix scene
One of the least enjoyable tasks of a journal editor is to nag referees to send reports. Many things have been tried to induce timeliness and responsiveness. We give deadlines. We allow referees to specify their own deadlines. We use automated nag-mails. We even allow referees to opt-in to automated nag-mails (they do and then still ignore them.)
When time has dragged on and a referee is not responding it is typical to send a message saying something like “please let me know if you still plan to provide a report, otherwise i will try to do without it.” These are usually ignored.
A few years ago I tried something new and every time since then it has gotten an almost immediate response, even from referees who have ignored multiple previous nudges. I have suggested it to other editors I know and it works for them too. I have an intuition for why it works (and that’s why I tried it in the first place) but I can’t quite articulate it, perhaps you have ideas. Here is the clinching message:
Dear X
I would like to respond soon to the authors but it would help me a lot if I could have your report. I realize that you are very busy, so if you think you will be able to send me a report within the next week, then please let me know. If you don’t think you will be able to send a report, then there is no need to respond to this message.
I listen to Pandora whenever I am in my office. It does a pretty good job of finding music that matches my taste, sometimes a really good job. In the past few weeks I’ve found some stuff that was completely new to me that I really liked. I created a station based on these tunes:
- Beep! Marty’s Mishap. I have never heard of this trio and as far as I can tell google has not either. The rhythm is an instrument if that makes any sense. This is exactly the kind of music I like.
- Nels Cline, Alstromeria. I don’t know how to classify this music. The guitar playing is virtuosity without showing off. The composition is academic without feeling pretentious.
- Tomasz Stanko Quartet, Kattorna. I first learned of this quartet in a roundabout way. The rhythm section has a few albums as a trio (The Marcin Waslez-somethingPolish-ski Trio) that I found on Pandora and really like. Then I learned that their main gig is this quartet led by trumpeter Tomasz Stanko. The quartet may be even better. Listen to what the piano is doing during the trumpet solos.
- Erik Friedlander, Quake. He plays cello. Lots of other people play lots of other instruments. Sometimes all at once. The music ranges from controlled chaos to the beautifully melodic.
- Rolf Lislevand, Toccata. Nuove Musiche with a modern sensibility. Beautiful.
- Moraz & Bruford, Living Space. Piano and drums, that’s it. But the pianist thinks he is playing the drums and the drummer thinks he is playing the piano.
All week this will be my music to read job-market files to. Join me.
Ahh, Evans Hall… (this is old yes, but still funny.)
I am very, very interested in studying one particular one: 18,000 bottles from the cellar of La Tour d’Argent are being auctioned off. It’s their first auction since the restaurant started in 1582. They are going through some tough times but:
Adversity is nothing new to La Tour d’Argent, which was pillaged in 1789 during the French Revolution. In the late 1980s, the wine cellar was flooded by the Seine River. And it was plundered in World War II, when the Nazis occupied the city.
The top wine is
a bottle of Corton, a red Burgundy, vintage 1895, its label blurred with mold and its price estimated at 1,000 ($1,488) to 1,200 euros ($1,786) .
The whole list is here. No “star” wines are being sold buy maybe that means there are bargains. It’s better to focus on wines that under the radar. If you still get excited and overbid, at least you can drink away your sorrow.
Tongue-in-cheek relationship advice from evolutionary psychology (via Mindhacks.)
Some Darwinists might say your optimal strategy would be to pair-bond with the older male but surreptitiously allow the younger, sexy male to fertilise you. But be careful, most men consider being cuckolded the greatest of betrayals.
And how about this?
You should have your husband medically assessed. It may be that some form of genetic disorder underlies his erratic behaviour, in which case he will need counselling and support. But you will also need to inform your daughters so that, if they are carriers, they do not themselves mate with men suffering from the same condition.
My 3rd-grade daughter had some interesting social science homework this week. Classify each of the following statements as either a fact or an opinion. (The first two are easy warm-ups.)
- As footwear, moccasins are better than sneakers.
- There are Iroquois living in New York State today.
- Many Native Americans were expert craftsmen.
- The Native American diet was more nutritious than our own.
- Europeans had no right to settle in North America.
- Native Americans should be treated with great respect.
The answers are after the jump. This is a public school. Still, be careful with your expectations about political correctness (and reverse political correctness.)
A simple implication of sexual selection is that there should be a correlation between features that attract us sexually and characteristics that make our offspring more fit. Here is an article that studies the link between physical attraction and success in sport.
The better an American football player, the more attractive he is, concludes a team led by Justin Park at the University of Bristol, UK. Park’s team had women rate the attractiveness of National Football League (NFL) quarterbacks: all were elite players, but the best were rated as more desirable.
Meanwhile, a survey of more than a thousand New Scientist Twitter followers reveals a similar trend for professional men’s tennis players.
Neither Park nor New Scientist argue that good looks promote good play. Rather, the same genetic variations could influence both traits.
“Athletic prowess may be a sexually selected trait that signals genetic quality,” Park says. So the same genetic factors that contribute to a handsome mug may also offer a slight competitive advantage to professional athletes.
Studies like this are prone to endogeneity problems because success also feeds back on physical attraction. At the extreme, we know who Roger Federer is and that gets in the way of judging his attractiveness directly. More subtly, if you show me pictures of two anonymous athletes, the one who is more successful has probably also trained better, eaten better, been raised differently and these are all endogenous characteristics that affect attractiveness directly. Knowing that they correlate with success doesn’t tell us whether “success genes” have physically attractive manifestations.
One way to improve the study would be to look at adopted children. Show subjects pictures of the athletes’ biological parents and ask the subjects to rate the attractiveness of the parents. Then correlate the responses with the performance of the children. If these children were raised by randomly selected parents (obviously that is not exactly the case) then we would be picking up the effect of exogenous sources of physical attractiveness passed on only through the genes of the parents.
And why stop with success in sport. Physical attractiveness should be correlated with intelligence, social mobility, etc.
Why is blackmail illegal? Sure it’s mean and all but what makes it a crime? This article raises some questions about the legal scholarship behind blackmail. (The background is the Letterman case.)
Whether or not this is how Hollywood really works, Shargel does have a point of logic. The reasoning that makes blackmail illegal–and a great many other similar business activities not illegal — is something that’s never been satisfactorily explained by legal scholars. It remains a paradox of the law. That said, Halderman and Shargel shouldn’t hold their breath until January, when a judge will rule on their motion to dismiss. Even if it makes no sense, blackmail remains a serious crime.
What about the economics of blackmail? There is one obvious economic rationale for making blackmail a crime: rent-seeking. Seeking out and producing incriminating evidence for the express purpose of ultimately keeping it secret is a waste of labor resources and should be discouraged. And this idea explains an otherwise puzzling asymmetry. That is, presumably I can legally accept payment in return for publicizing good information about you. That is tantamount to threatening not to publicize it if you don’t pay me. Whether I threaten withold good information about you or actively publicize bad information about you I am arguably doing the same thing: threatening to lower your reputation relative to what it would otherwise be.
The economic difference is that allowing blackmail leads to unproductive rent-seeking whereas allowing me to charge you for good publicity incentivizes productive information-gathering.
In rare cases blackmail is efficient. If I want you to dig up the dirt on me (perhaps to keep it out of more dangerous hands) we have an incentive problem. I can’t pay you up front because then you have no incentive to do the search. You will come back claiming that my record is so clean that despite all your efforts you came up empty-handed. Instead I would like to pay you ex post in return for the documents. But once you’ve already sunk the cost of searching, I will hold you up and try to renegotiate the fee. The information is not worth anything to you since blackmail is illegal. We would both prefer to allow you to blackmail me ex post. That way I am effectively commited to pay you for your service and you will work hard.
You can trust me to pay you for the information but now the problem is that I can’t trust you. You will show me only half of what you found and blackmail me to keep that a secret. Once you have your money you will show me the other half and blackmail me again. Forseeing this I won’t pay you the first time.
Once you think of this its hard to see how blackmail works at all and why we need to even make it illegal. The blackmailer has to somehow prove that he is not hiding any additional information. That is probably impossible because any incriminating evidence can be copied.
Maybe the problem can be solved with a reciprocal arrangement. You dig up some dirt on me and yourself. Then you offer me the following deal. I pay you the hush money and you hand over the information about you. I will pay you because in return I get a threat against you which deters you from blackmailing me again.
In 2006, the pharma company Cephalon faced entry by generic drug producers. It’s blockbuster drug Provigil was coming to the end of its patent protection. The solution – buy off the competitors for an extra six year window:
Cephalon negotiated separate deals with four generic drug makers — Teva Pharmaceuticals, Ranbaxy Laboratories, Mylan Pharmaceuticals and Barr Laboratories — seeking to develop generic versions of Provigil.
Under those settlement agreements, Cephalon granted the generic drug makers non-exclusive, royalty-bearing rights to market and sell a generic version of Provigil starting in October 2011, or April 2012 if Cephalon obtains a pediatric extension for the drug. Cephalon maintains it has valid patents for Provigil until that time frame.
In documents filed with the Securities and Exchange Commission, Cephalon disclosed it received licenses to certain modafinil-related intellectual property developed by the generic-drug companies. In exchange for the licenses, Cephalon agreed to make payments to Barr, Ranbaxy and Teva “collectively totaling up to $136.00 million over the next several years.”
And this is legal apparently.
(Hat tip: Zachary Roth at Talking Points Memo)
From an entertaining article in the Financial Times that develops the analogy between the interconnectedness of financial instruments and biological ecosystems.
“From an individual firm’s perspective, these strategies looked like sensible attempts to purge risk through diversification: more eggs are being placed in the basket,” says Mr Haldane. “Viewed across the system as a whole, however, it is clear now that these strategies generated the opposite result: the greater the number of eggs, the greater the fragility of the basket – and the greater the probability of bad eggs.”
That is what a mathematical ecologist would have predicted if he or she had known what was going on in the world of finance. The tropical rainforest, for example, has so many interdependent species that it is more vulnerable to an external shock than the simpler ecological diversity of savannahs and grasslands.
I wonder what prescription naturally arises from this perspective? Total laissez-faire so that the financial system can suffer enough crashes, extinctions, and re-organizations to find a configuration that is stable for the long run? Would we someday see Business schools sending missions out to shuttering financial institutions clamoring for intervention in the name of preserving derivative-diversity. What is the analog of sexual reproduction and random genetic mixing?
Straight from the horse’s mouth….well, Dubner and Levitt’s, as interviewed by Jorn-Steffen Pischke of LSE.
You have to scroll down to Nov 9, 2009 to find the video. Lots of other interesting videos there…..Sen, Krugman, Bueno de Mesquita.
This article from New Scientist asks whether sleep walkers can be held morally responsible for acts committed while unconscious. A different question is what effect a sleepwalker exception would have on crime. Would it encourage sleepwalkers to commit more crimes, or on the extensive margin would it encourage more to people to take up sleepwalking?
I have no personal experience, but if sleepwalkers believe they are awake, then they would not be motivated by an exemption for sleepwalkers. Of course at any moment in time all of us may be sleepwalking and assuming we all account for that small probability, a sleepwalker exemption would encourage more crime across the board. This could be easily compensated by a small, uniform increase in penalties.
We shold worry that non-sleepwalkers will make use of the additional defense at trial (the “jammie defense?”)
Nightcap Nod: Mindhacks.
For the operative who is confused about polite, Talibany behavior, the senior leadership has been kind enough to offer a code of conduct. It is written in a spartan and logical fashion, point by point, a bit like the work of Ludwig Wittgenstein.
Number 15 is their policy on torture:
If some one admits that he is spy because you forced or tortured him, that does not make this person a spy and you can’t punish him. lt is prohibited for a Mujahid to promise to someone that if he admits then he will not be killed, he will be let go, or will not be tortured. There are two kinds of promises: the first is forcing, like you are telling him if you admit then we will let you go or we are not going torture you or put you in jail. lf you use force to cause admission, this is not legitimate. Second, you do not use force but you tell him that if you admit we will give you money or a high ranking position. This method also is not legitimate.
They recognize the possibility of false confessions using stick-based incentives like torture. Interestingly, the humble Mujahid is not even allowed to use carrot-based incentives. There is a problem of generating false confessions from an informant who just wants to get a reward.
The Taliban also know a little elementary implementation theory. One method to determine if someone is a spy is if (point 14): “There are two witnesses
that testify such person is a spy” (my emphasis). We can improve incentives to tell the truth if we can cross-check what one person reports against what another reports. If only one person says someone is a spy, there is the possibility the informant is lying for some reason – personal animosity, theft of the purported spy’s possessions once he is killed or incarcerated etc. But if we require two informants to say the person in question is a spy, if the two contradict each other, the senior Taliban can at the very least investigate further. The simplest way to encourage truthtelling is to punish both informants if they contradict each other. The document does not elaborate on this and relies on ambiguity of outcome (fear of repercussions?) to suffice to give incentives. The contract is incomplete in other words….another issue that is a concern of mechanism design and contract theory.
I didn’t see any repeated games insights though. Maybe in the next version.
I am going to write an insurance contract with you. We agree that if an accident happens I will cover you unless you a type prone to accident or you don’t try hard enough to avoid an accident.
There are two ways we can implement these conditionals. We could investigate whether they hold at the time we sign the contract or we could wait until an accident happens. Since an accident is unlikely to happen, the second method often avoids unnecessary costs of investigation and makes it cheaper to enforce the contract. That means I can offer you a lower premium.
All of this assumes that the conditions that would nullify the contract are
- completely described either in the contract or in law,
- fully understood by the insured, and
- within the information set of the insured
Arguments against rescision can be based on any one of these three being violated. Certainly #1 is violated in practice if insurance companies are free to present any evidence suggestive of, for example, pre-existing conditions. Violations of #2 plagues all economic analysis of contracts, no doubt it is a problem here as well. And an argument against recision could be based on #3, even if we assume that contracts are complete and voluntary.
Indeed I believe that #3 is the basis for a response to the obvious “If allowing for recision is against the interests of the insured, why don’t insurers compete by offering no-rescision contracts.” These would have higher premiums for the reasons given above. Insurees would tend to reject these in favor of lower-premium rescision-permitting contracts when they are not aware of buried, jargon-laden, medical records that would nullify their coverage. In fact, the asymmetric access to this information superimposes an artificial asymmetric information problem on an insurance market that is already plagued by adverse selection.
Here’s a research problem: what does a competitive equilibrium look like in an insurance market where both types of contract can be offered? Assume that the insurer has superior information about documentation of pre-existing conditions, and conditions contract terms on its private information.
Cheap Talk 