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The District of Columbia is testing a system to allow overseas military personnel submit absentee electronic ballots via the internet. Obviously security is a major concern and the followed a suggestion often made by the security community to open the system to the public and allow white-hat hackers to try and find exploits. Here is the account of one team who participated and found a vulnerability within 36 hours.
By formatting the string in a particular way, we could cause the server to execute commands on our behalf. For example, the filename “ballot.$(sleep 10)pdf” would cause the server to pause for ten seconds (executing the “sleep 10” command) before responding. In effect, this vulnerability allowed us to remotely log in to the server as a privileged user
As a result, deployment of the system has been delayed.
This is exactly the kind of open, public testing that many of us in the e-voting security community — including me — have been encouraging vendors and municipalities to conduct.
But it could have turned out differently. If a black-hat got there first, they could fix the vulnerability after first leaving themselves a backdoor. Then the test comes out looking like a success, it goes live, and …
Here are votes from some interested subset from NU Econ and Kellogg. NU and Kellogg Management and Strategy have lots of I.O. specialists and Dale Mortensen is in the Economics Department. Plus we have lots of theorists. The closest I have to a coherent story from this data is a prize for “search theory” with Diamond, Mortensen and Pissarides.
Tyler Cowen invites us to ponder this game:
Rejection Therapy is a real life game with one rule: to be rejected by someone every single day, for 30 days consecutive. There are even suggestion cards available for “rejection attempts” (although they are not essential to the game).
I am not sure about rejection as therapy, any more than the general principle that it is therapeutic to expose yourself to new, perhaps uncomfortable experiences all the time.
But rejection is a very simple yardstick by which to judge how often and how hard you are trying, how high you are aiming. We should push those margins as far as they can go, up to the point of negative marginal returns. We have not passed that threshold until the rejection rate is positive.
So, whether or not it is an end in itself, a daily dose of rejection is the hallmark of a life lived to the fullest.
Ariel Rubinstein wrote the Afterword for the 2007 reprinting of the book that launched Game Theory as a field, von Neumann and Morgenstern’s Theory of Games and Economic Behavior. Here is a representative excerpt:
Others (including myself) think that the object of game theory is primarily to study the considerations used in decision making in interactive situations. It identifies patterns of reasoning and investigates their implications on decision making in strategic situations. Accordingto this opinion, game theory does not have normative implications and its empirical significance is very limited. Game theory is viewed as a cousin of logic. Logic does not allow us to screen out true statements from false ones and does not help us distinguish right from wrong. Game theory does not tell us which action is preferable or predict what other people will do. If game theory is nevertheless useful or practical, it is only indirectly so. In any case, the burden of proof is on those who use game theory to make policy recommendations, not on those who doubt the practical value of game theory in the first place.
And, by the way, I sometimes wonder why people are so obsessed in looking for “usefulness” in economics generally and game theory in particular. Should academic research be judged by its usefulness?
Tam o’Shanter Toss: Russ Roberts
If a tree falls in a forest and no one is around to hear it, does it make a sound?
This old philosophical conundrum can be mapped into the dilemma facing the aging academic:
If I publish a paper and nobody reads it, teaches it or cites it, can it ever be a truly great paper?
As with all questions with no Platonic certitude, economists say: Let the market speak and tell us the answer.
Glenn Ellison has studied a more serious version of my question in his paper “How Does the Market Use Citation Data? The Hirsch Index in Economics.” The Hirsch index for an author is the highest number h such that the author has h papers with at least h citations. So, an index of 5 means you have five papers with at least five citations and that you do not have six papers with at least six citations etc.
Glenn points out that the Hirsch index doesn’t do a great job at ranking economists. Nobel prize winner Roger Myerson’s Hirsch index is a mere 32. But he has a few papers with over a thousand citations. Seminal papers in economics tend to get a huge number of citations but most only get a few. So, the plain vanilla Hirsch index needs to be re-evaluated.
Glenn turns to the market to guide his measure. He studies an index of the form h is the highest number such that the author has at least h papers with at least a times h to the power b citations. The plain vanilla Hirsch index sets a=b=1. Glenn estimates a and b in various ways. In one method, he looks at the NRC department rankings and finds the variables a and b that best predict the NRC rank of a (young) economist’s department. To cut a long story short, a=5 and b=2 come out as the best predictors. With this estimation in hand, we can perform various comparisons – Which fields are highly cited? Which economists are highly cited? Etc..
Here are some tasty morsels of information. International finance, trade and behavioral economics are highly cited fields (Table 6). Micro theory and cross-sectional econometrics are the worst and IO does not do too well either. These facts mean Yale and NU, which are strong in these three areas, are under-cited economics departments. But basically one gets the picture that an economists citations are closely connected to the rank of the university where s/he is employed.
Ranking young economists, it is pretty obvious who is going to come out on top: Daron Acemoglu with an index of 7.84 (Table 7). This means Daron has 7.84 papers with roughly 300 citations. Ed Glaeser and Chad Jones are close behind. Once you adjust by field, more theorists start to rank highly: Glenn, Ilya Segal, Stephen Morris and Susan Athey pop up. Also, my friend Aviv Nevo gets a shout out as an underplaced guy.
A few comments:
Most of these people are tenured well before their citations go crazy. Expert opinion not data-mining leads to their tenure. This tells you how well expert opinion predicts citations. Also, to the extent that citations take time, expert opinion will always play a role in tenure decisions. There is a difference between external opinion and internal opinion. The same few people always get asked to write letters and they will do a good job. But internal opinions may be more noisy and depend on the quality of the department. Then, Glenn’s field-adjusted citation measure gives you some idea of a candidate’s quality and might be a valuable input into the tenure decision.
Finally, there are citations and citations. A paper getting regular cites in top journals is better than a paper getting cites in lower tier journals. This can be dealt with by improving the citation index.
At another extreme, some papers may be journalistic, not academic, and then their citations mean less. For example, Malcom Gladwell gets high citations for the Tipping Point but he did not do any of the original scientific research on which his book is based. Of course he writes wonderfully and comes up with amazing examples and he is clearly an intellectual. I bet Harvard would love to have him an as an adjunct professor but they will not give him a tenured professorship.
Despite these caveats, the generalized Hirsch index is an interesting input for academic decision-making.
Poker players know that the eyes never lie. Indeed your eyes almost always signal your intentions for the simple reason that you have to see what you intend to do.
This is an essential difference between communication with eye movement/eye contact and other forms of communication. The connection between what you know and what you say is entirely your choice and of course you will always use this freedom to your advantage. But what you are looking at and where your eyes move are inevitably linked.
Naturally your friends and enemies have learned, indeed evolved to exploit this connection. Even the tiniest changes in your gaze are detectable. As an example, think of the strange feeling of having a conversation with someone who has a lazy eye.
Given that Mother Nature reveals such a strong evolutionary advantage for reading another’s gaze the question then arises why we have not evolved to mask it from those who would take advantage? The answer must be that it would in fact not be to our advantage.
With any form of communication, sometimes you want to be truthful and other times you want to deceive. The physical link between your attention and your gaze means that, for this particular form of communication you can’t have it both ways. Outright deception being impossible, at best Nature could hide our gaze altogether, say by uniformly coloring the entire eye.
But she chose not to. By Nature’s revealed preference, this particular form of honesty is evolutionarily advantageous, at least on average.
Ray Fisman at Slate describes a new paper by David Card, Alexandre Mas, Enrico Moretti and Emanual Saez . These researchers use publicly available salary data for the University of California to study whether workers are disgruntled when they learn they are earning less than their colleagues. The Sacramento Bee has a website which allows anyone to search for salaries by name or institution. The researchers told some employees about the website so they could search for information about their colleagues’ salaries. They then asked all employees about their job satisfaction. Comparing the groups gives an estimate of the impact of knowing salaries on job satisfaction. Fisman reports:
On average, receiving SacBee information via e-mail had little effect on job satisfaction or job-search plans. But when the researchers divided the sample in half—those above the median pay level for comparable individuals in their department and those below—they found low earners were significantly more likely to report low job and wage satisfaction if they received the SacBee e-mail. The SacBee e-mail had an even greater impact on the likelihood of low wage earners responding that they would be looking for a job in the coming year. (One respondent even sent a note to the researchers letting them know that he handed in his resignation shortly after checking his colleagues’ salaries on the SacBee Web site.) Surprisingly, high earners didn’t revel in their relative superiority—exposure to the SacBee Web site had no effect on their job satisfaction or likelihood of looking for a new job. (The researchers also found that both low and high earners expressed greater concern for income inequality in America after poking around the SacBee’s salary database.)
I’ve dressed up this post to look intellectual but really I know and you know that we want the juicy stuff:
1. Fisman’s link to the SacBee website is here.
2. What about other universities? Dan Hamermesh’s Gossip Files provide some more information….
There’s only so much time in the day so we can’t talk about everything. Given the opportunity cost, ideas that are obviously bad aren’t worth talking about, even if you are someone who always considers both sides of every issue. This means that if you discuss an idea you demonstrate that you don’t think it’s obviously bad, even if what you conclude from your discussion is that the idea is obviously bad.
Now if I think that an idea is obviously bad and I hear a friend, or politician, or media outlet engage in a discussion of both sides of that issue, I conclude that they have the wrong priorities, even if they ultimately agree with me on the idea. Therefore, my friends, politicians who want my vote, and media who want me to listen to them will not even bring up ideas that I think are obviously bad. Even if I am wrong.
You can subscribe to a service and receive calls reminding you that you are awesome (ht MR).
You can probably think of people who would buy this service thinking it will bolster their self-esteem. You might even imagine that you yourself would get a little boost from having someone call you personally and tell you that you rock. But you probably think that this is leveraging some kind of behavioral, kludgy, semi-rational wiring in your personality and that you would quickly get de-sensitized to it.
But I disagree. I think that it would be a valuable motivator even for the most hyper-rational among us. Because it’s not a trick at all but really just a way to preserve mindsets over time. Suppose I tell you about something great I did. Then later on, when I am about to take on some challenge, like let’s say I am about to give a big lecture to an intimidating audience, you call me and remind me of the great thing I did. And you add your own interpretation of why it was great and how it shows that I am awesome. I don’t need to believe anything about your motivations, your reminder restores my brain to the state it was in when I myself was thinking about how great I am and why. And if your added color convinces me that you honestly agree with me then all the better.
Simply “writing it down” or memorizing the state of mind is not a perfect substitute. At a very minimum this is simply based on cost-minimization. Someone else is doing the remembering for me and that is worth something. But it’s even more than that.
If you have been following me it will come as no surprise that I have no trouble at all remembering what an stupendous guy I am and all the super-amazing feats of astounding splendifery I have accomplished in my life. Yet even with that overflowing supply of memories of greatness, I still get nervous in the face of a challenge. When that happens I have my daughter repeat something she once said to me at a minor moment of greatness: “you’re so smart daddy.” The memory of that moment is imprinted on the sound of her voice. That sound hooks into the vivid edges of my direct experience of the event. Immediately it’s “oh yeah, that’s how it’s done” and my perspective on the situation is totally new. And yet on the surface all she is doing is duplicating a memory that I had in there already.
Daughters are great, and not just for fueling your ego, but they cost more than $40 a month. By comparison, Awesomeness Reminders look like a pretty good deal.
They say you can’t compare the greats from yesteryear with the stars of today. But when it comes to Nobel laureates, to some extent you can.
The Nobel committee is just like a kid with a bag of candy. Every day (year) he has to decide which piece of candy to eat (to whom to give the prize) and each day some new candy might be added to his bag (new candidates come on the scene.) The twist is that each piece of candy has a random expiration date (economists randomly perish) so sometimes it is optimal to defer eating his favorite piece of candy in order to enjoy another which otherwise might go to waste.
The empirical question we are then left with is to uncover the Nobel committee’s underlying ranking of economists based on the awards actually given over time. It’s not so simple, but there are some clear inferences we can make. (Here’s a list of Laureates up to 2006, with their ages.)
To see that it is not so simple, note that just because X got the prize and Y didn’t doesn’t mean that X is better than Y. It could have been that the committee planned eventually to give the prize to Y but Y died earlier than expected (or Y is still alive and the time has not yet arrrived.)
When would the committee award the prize to X before Y despite ranking Y ahead of X? A necessary condition is that Y is older than X and is therefore going to expire sooner. (I am assuming here that age is a sufficient statistic for mortality risk.) That gives us our one clear inference:
If X received the prize before Y and X was born later than Y then X is revealed to be better than Y.
(The specific wording is to emphasize that it is calendar age that matters, not age at the time of receiving the prize. Also if Y never received the prize at all that counts too.)
Looking at the data, we can then infer some rankings.
One of the first economists to win the prize, Ragnar Frisch (who??) is not revealed preferred to anybody. By contrast, Paul Samuelson, who won the very next year is revealed preferred to kuznets, hicks, leontif, von hayk, myrdal, kantorovich, koopmans, friedman, meade, ohlin, lewis, schulz, stigler, stone, allais, haavelmo, coase and vickrey.
Outdoing Samuelson is Ken Arrow, who is revealed preferred to everyone Samuelson is plus simon, klein, tobin, debreu, buchanan, north, harsanyi, schelling and hurwicz (! hurwicz won the prize 37 years later!), but minus kuznets (a total of 25!)
Also very impressive is Robert Merton who had an incredible streak of being revealed preferred to everyone winning the prize from 1998 to 2006, ended only by Maskin and Myerson (but see below.)
On the flipside, there’s Tom Schelling who is revealed to be worse than 28 other Laureates. Leo Hurwicz is revealed to be worse than all of those plus Phelps. Hurwicz is not revealed preferred to anybody, a distinction he shares with Vickrey, Havelmo, Schultz (who??), Myrdal (?), Kuznets and Frisch.
Paul Krugman is batting 1,000 having been revealed preferred to all (two) candidates coming after him: Williamson and Ostrom.
Similar exercises could be carried out with any prize that has a “lifetime achievement” flavor (for example Sophia Loren is revealed preferred to Sidney Poitier, natch.)
There’s a real research program here which should send decision theorists racing to their whiteboards. We deduced one revealed preference implication. Question: is that all we can deduce or are there other implied relations? This is actually a family of questions that depend on how strong assumptions we want to make about the expiration dates in the candy bag. At one extreme we could ask “is any ranking consistent with the boldface rule above rationalizable by some expiration dates known to the child but not to us?” My conjecture is yes, i.e. that the boldface rule exhausts all we can infer.
At the other end, we might assume that the committee knows only the age of the candidates and assumes that everyone of a given age has the average mortality rate for that age (in the United States or Europe.) This potentially makes it harder to rationalize arbitrary choices and could lead to more inferences. This appears to be a tricky question (the infinite horizon introduces some subtleties. Surely though Ken Arrow has already solved it but is too modest to publish it.)
Of course, the committee might have figured out that we are making inferences like this and then would leverage those to send stronger signals. For example, giving the prize to Krugman at age 56 becomes a very strong signal. This would add some noise.
Finally, the kid-with-a-candy-bag analogy breaks down when we notice that the committee forms bundles. Individual rankings can still be inferred but more considerations come into play. Maskin and Myerson got the prize very young, but Hurwicz, with whom they shared the prize, was very close to expiration. We can say that the oldest in a bundle is revealed preferred to anyone older who receives a prize later. Plus we can infer rankings of fields by looking at the timing of prizes awarded to researchers in similar areas. For example, time-series econometrics (2003) is revealed preferred to the theory of organizations (2009.)
The Bottom Line: There is clear advice here for those hoping to win the prize this year, and those who actually do. If you do win the prize, for your acceptance speech you should start by doing pushups to prove how virile you are. This signals to the world that you were not given the award because of an impending expiration date but that in fact there was still plenty of time left but the committee still saw fit to act now. And if you fear you will never win the prize, the sooner you expire the more willing will the public be to believe that you would have won if only you had stuck around.
A California Classic. Totally delicious. Three distinct phases of the palette. Fruit at first: Strawberry but also Cherry, like a Burgundy. That leaves to be replaced by acid and then finally a long, spicy finish. Lots of Clove and Pepper.
Wish it was a bit lower in alcohol – I hard a hard time waking up this morning!
I believe this wine was one of the original Rhone Rangers – California’s attempt to replicate Rhone style wines. It’s way cheaper ($30 approx.) than a good, reliable CdP and there is considerable complexity and none of the usual fruity, oaky availability of usual California style wines.
Cheap Talk 