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Two public service announcements. The first about post-doc positions. The second about nominations for SIGecom dissertation awards.
Penn’s newly-launched Warren Center for Network and Data Sciences seeks nominations for 2014 Warren Postdoctoral Fellowships. Warren Fellow candidates should have research interests in the subjects supported by the center, which include but are not limited to network science (including the study of social, technological, economic, organizational and biological networks, as well as underlying foundational areas such as graph theory, game theory, mechanism design) and data science (including machine learning, statistics, data privacy and security). The ideal candidate will have a strongly interdisciplinary research agenda with a demonstrated track record, and would be nominated by faculty affiliates of the Warren Center in two or more Penn departments who will act as hosts, advisors and collaborators of the candidate.
Warren Postdoctoral Fellows will receive generous and competitive stipends and research support, and will participate in a vibrant and community of Warren Center faculty affiliates, postdocs and students. We expect to fund multiple Warren Fellows for the 2014-15 academic year. Fellowships are for a one-year period, extendable to two by mutual agreement.
SIGecom Doctoral Dissertation Award for dissertations defended in 2013. Nomination deadline end of February, 2014.
The journal Econometrica is spelt as I just wrote. The journal Biometrika, however, has a `k’ in place of the letter `c’. Biometrika has it right, and Pearson its founder credits Edgeworth for this:
……like a good German he knew that the Greek `k’ is not a modern `c’, and, if any of you at any time wonder where the `k’ in Biometrika comes from, I will frankly confess that I stole it from Edgeworth. Whenever you see that `k’ call to mind dear old Edgeworth.
If there is a heaven, the creators of the Dos Equis adverts about the most interesting man in the world will go there. In idle moments, I cannot help but recall some of them:
his two cents are worth $37 and change.
Which prompts one to wonder about what the most interesting Economist in the World is like. So has someone else. Therefore, imagine, the music of the Dos Equis ad playing in the background and the velvet voice of William Lyman purring:
He is the life of seminars that he has never attended.
He once submitted a paper to Econometrica under a pseudonym just to see what rejection felt like.
Adam Smith quotes him.
He is the most interesting Economist in the world.
My colleague James Schummer was kind enough to point me to the following news item, which quotes George Lucas as predicting that one day a cinema ticket will cost $150. Mr. Lucas and (and Mr. Spielberg) believe that the movie industry will, over time, concentrate on big budget productions and these will cost more to see in the cinema. Indeed, one senior equity analyst at Morningstar is quoted as saying:
differentiated pricing according to the movie’s budget makes economic sense.
I think this is the sentence that caught my colleague’s eye.
He and I teach a class on pricing. In it we emphasize the simple point that fixed costs are irrelevant for deciding the price. If I could repeat this FACT in large friendly letters like the warning on the Hitchiker’s Guide to the Galaxy, I would. So, the idea that a movie’s budget should determine its price is not merely wrong but risible.
It is based on a proposal by Merrifield and Saari. This is not the only proposal for revamping peer review based on mechanism design ideas. See Robinson. Solomon provides a brief summary of other proposals to upend peer review and how they fared.
Merrifeld & Saari assert that an ideal peer review process must solve the following problems ( quote from the paper):
a) Some incentive should be put in place to reduce the pressure toward ever more applications.
b) The workload of assessment should be shared equitably around the community.
c) The burden on each individual should be maintained at a reasonable level so that it is physically
possible to do a fair and thorough job.
d) There should be some positive incentive to do the task well.
e) The ultimate ranked list of applications should be as objective a representation of the
community’s perception of their relative scientific merits as possible.
Their proposed mechanism (with extraneous but important practical details omitted) is as follows:
1) There are N agents each of whom submits a proposal.
2) Each agent receives m < N proposals to review (not their own).
3) Each agent compiles a ranked list of the m she receives, placing them in the order in which she thinks the community would rank them, not her personal preferences.
4) The N ranked lists are combined to produce an optimized global list ranking all N applications.
5) Failure to carry out this refereeing duty by a set deadline leads to automatic rejection of one's proposal.
6) Individual rankings are compared to the positions of the same m applications in the globally-optimized list. If both lists appear in approximately the same order, then proposer is rewarded by having his proposal moved a modest number of places up the final list relative to those from proposers who have not matched the community’s view as well.
What is missing from the paper or the summary on the NSF site is a clear specification of an environment in which such a mechanism is any sense the best such mechanism satisfying (a-e). In this sense it is not a `mechanism design' approach to peer review. One could dismiss this as pettiffogging, but it would be mistaken. To illustrate, lets posit an environment. Suppose N=3 and m=2. So each agent reviews the proposals by the other two. Suppose also each proposal is either good or bad, and conditional on its state anyone reviewing it receives a signal of its quality. So, good proposals generate a high quality signal with probability 1 and bad proposals generate a low quality signal with probability 1. The signals are independent across reviewers. Finally, the cost of effort to review a proposal is zero.
Proposers read the proposals assigned to them, and report their signals. If two proposers disagree on the same proposal, both are shot (and extreme version of item (6) above). Thus, truthfully reporting one's signal is an equilibrium. However, it is not the only equilibrium. Randomizing one's report would also be an equilibrium……..which may obtain if there is a non-negligble cost of effort. Now, Merrifield & Saari might argue that the environment I've set up presumes there are objectively good proposals which is ruled out by them. They write `……it should be borne in mind that there is no objective right answer in this kind of peer review process.' I would argue, this is semantic. The `true' quality is simply the commonly known community perception of quality.
There may a way a round the multiplicity of equilibria problem here using an idea explicated by David Rahman in his aptly titled paper which I render in latin: Quis custodiet ipsos custodes? What is it? Insert proposals with known quality into the review, i.e., test the agents.
I have also assumed the cost of effort is zero, and one goal of the Merrifield & Saari proposal is to encourage effort because it is costly. However, this suggests a trade-off between costly effort and information revealed. Might Merrifield and Saari’s proposal encourage too much effort?
By the by, why exclude agents reviewing their own proposals? Presumably item (6) will discourage grossly inflated rankings of one’s own proposals. It does bring to mind David Lodge’s parlour game `Humiliation’ in Changing Places. Players name classics of literature that they have not read, the winner being the one who confesses the most embarrassing omission. (In the book an untenured professor desperate to impress his colleagues admits to skipping Hamlet and for this lacunae is subsequently denied tenure.)
Step away, now, from the proposal and focus on the desidarata (a-e) that Merrifield and Saari identify. Some of it has to do with the moral hazard problem. Effort is costly, how can I ensure that you exerted effort? The interesting twist in the present context, is that there is no obvious signal of effort that can be relied upon. Thus, any mechanism that meets criteria (a-e) must simultaneously elicit private information, and induce the right level of effort without the injection of outside resources. I think, this has to be impossible. So, there is an impossibility result lurking here to be formulated and proved.
There is a debate underway about how effective Israel’s iron dome system is in protecting populated areas from missile attacks. On the pro side it is argued that somewhere between 85% to 90% of incoming missiles are destroyed. The con side argues that the proportion is much smaller, 40% or less. A large part of the difference comes from how one defines `destroy’. Perhaps a better term would be intercept. It is possible that about 90% of incoming missiles are intercepted. However, a missile once intercepted may not have its warhead disabled, making at least one of the fragments that falls to ground (in a populated area) dangerous.
While nailing down the actual numbers may be interesting, it strikes me as irrelevant. Suppose that any incoming missile has a 90% chance of being intercepted and destroyed (which is the claim of the builder of the iron dome technology). If the attacker launches N missiles and iron dome is deployed, the probability (assuming independence) not a single one making it through is (0.9)^N. Thus, the probability of at least one missile making it through the `dome’ is 1 – (0.9)^N. If N is large, this is large. For example, for N = 10, the probability that at least one missile makes its way through is at least 60% (thanks to anonymous below for correction). Thus, as long as the attacker has access to large quantities of missiles, it can be sure to get missiles through the dome.
In the course of a pleasant dinner, conversation turned to dictatorship and the organization of markets. At this point, Roger Myerson, remarked upon the absence of inter-species trade. He was not, of course, referring to trade with alien beings from another planet (who would have discovered correlated equilibrium before Nash equilibrium). Rather, the absence of trade with, say, monkeys. Adam Smith, went further and denied the possibility of trade between animals.
Nobody ever saw a dog make a fair and deliberate exchange of one bone for another with another dog. Nobody ever saw one animal by its gestures and natural cries signify to another, this is mine, that yours………
There is a long history of interactions between men and monkeys of various kinds. Monkeys have been marauders of crops, domestic companions, religious symbols and commodities (meat). The interactions between the species seems to fall into one of three categories: pure conflict (keeping out marauders), long run relationships (pets) or exploitation (used in labs and as entertainment). However, no examples of what one might call trade in the sense of voluntary arms length transactions involving barter. For example, why don’t villagers `pay’ bands of roving monkeys to not pillage?
There is evidence to indicating they would be capable of understanding such transactions. Gomes and Boesch, for example, suggest that monkeys trade meat for sex. Then, there is Keith Chen’s monkey study which suggests that one could teach (some) monkeys about money. From the Jesuit traveller Jose de Acosta in the 1500′s we have the following charming account:
I sawe one [monkey] in Carthagene [Cartagena] in the Governour’s house, so taught, as the things he did seemed incredible: they sent him to the Taverne for wine, putting the pot in one hand, and the money in the other; and they could not possibly gette the money out of his hand, before he had his pot full of wine.
A little known fact about Canada is that it is the world’s largest producer of famous Americans. Recall, for example, John Kenneth Galbraith, Wayne Gretzky, William Shatner, Michael J. Fox, Malcolm Gladwell, Shirley Tilghman and Keanu Reeves. Some have suggested that Obama is a Canadian, leading to a split in the birther movement between the original birthers and the neo-birthers. Originalists believe that Obama was sired in a Kenyan village, imbued with an anti-colonial mindset, leavened by Saul Alinsky radicalism and smuggled into the US with the intent of turning the US into an Islamic caliphate. The neo-birthers believe that this beggars belief. It is simpler, they say, to believe that Obama is Canadian.