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See the notice on the Game Theory Society website.

hardy's 11

G. H. Hardy leading his cricket team out onto the pitch.

A word that Paul Romer used in a recent piece in the Papers and Proceedings of the AER. Its inspired, no doubt, by Stephen Colbert’s notion of `truthiness’. Romer defines it as

Like mathematical theory, mathiness uses a mixture of words and symbols, but instead of making tight links, it leaves ample room for slippage between statements in natural versus formal language and between statements with theoretical as opposed to empirical content.

Romer is not the first to coin the term. Credit goes, I think, to Jordan Ellenberg. Ellenberg defined it as

…..a series of fervent gestures that gives the impression that mathematical ideas are being expressed, but doesn’t actually deliver the goods.

The recent turmoil in Baltimore and the news of Ray Fisman’s impending move to Boston University reminded me that he (along with Tim Sullivan) had penned a column for Slate on Jan 7, 2013 entitled:

Excellent Police: What the Baltimore P.D. can teach your office about multitasking and incentives.

In hindsight, the title seems ironic. The article itself is an excerpt from the author’s book on Organizations (in the genre pioneered by Freakanomics) and can be interpreted as illustration of Goodhart’s law. The article itself does not align perfectly with the title. Apparently, what the Baltimore PD has to teach us is what not to do as the following quote suggests:

To illustrate the double-edged sword of arrest incentives, Moskos recounts the example of a fellow officer who decided to set a record for monthly arrests. His plan: lock people up for violating bicycle regulations. At night, all bikes need a light. The officer would stop cyclists in breach of the bike light rule (which was most of them), ask for ID, and pull out his pad to write a citation. Most riders, though, were biking without ID, and since all offenses become arrestable without identification, the officer’s little scheme netted 26 arrests in a single month. A record. His sergeant was thrilled, telling Moskos, “Look, I don’t know what his motivations are. But I think it’s good. He’s locking people up, which is more than half the people in this squad.”

Finally got around to reading the PCES report on economics education at Manchester. The Francis Urquhart  half of my dual selves was duty bound to dislike it. My Urquhart self, would urge the authors to switch subjects and find  fulfilling careers in one of the caring professions, like, personal incontinence counselor. My milquetoast self prevailed and I buckled down to read it.

The report raises two issues and its writers have made the mistake of conflating them or at least not separating them clearly enough. The first is the effectiveness with which economics is taught. The second is what is to be taught.

On the first, the report makes for depressing reading. It summarizes an economics education as dull as ice fishing. For those unfamiliar with ice fishing, it is a sport (and thats being charitable) practiced by the inhabitants of Minnesota and the remoter parts of Wisconsin. In dead of winter, one drives a large vehicle over a frozen lake. If that were insufficient to tempt fate, one then cuts a hole in the ice for the ostensible purpose of catching fish. In practice one sits around the hole drinking prodigously while trying not to fall in. Beans, flatulance and an absence of sanitation figure prominently.

On the second, the report’s authors write

Our economics education has raised one paradigm, often referred to as neoclassical economics, to the sole object of study. Alternative perspectives have been marginalised. This stifles innovation, damages creativity and suppresses constructive criticisms that are so vital for economic understanding. Furthermore, the study of ethics, politics and history are almost completely absent from the syllabus. We propose that economics cannot be understood with all these aspects excluded; the discipline must be redefined.

Exposure to history, psychology and politics? Of course, yes. Within the US system this happens naturally as a function of breadth requirements. Students are not shy about trying to reconcile what they have learnt in Psychology and what they are mastering in Economics. It makes for a lively classroom.

What about these alternative perspectives? In for a penny in for a pound, so I decided to read a paper  by Steven Keen. Keen, as far as I can gather is one of the leading lights of these alternative perspectives. The paper I read (co-authored with Russell Standish) appeared in Physica A and can be found here. If you’ve not heard of it, there is a good reason for that. Continue to ignore it. Pauli might have described it thus:

Das ist nicht nur nicht richtig, es ist nicht einmal falsch!

Reading it lowered my IQ, something I can scarce afford to do. If this is representative of what passes for alternative perspectives, the writers of the PCES should leave economics and find fulfilling careers as incontinence counselors. Finally, for those who think my description of Keen and Standish uncharitable, I refer them to the following by Chris Auld.  Stamping out ignorance is a thankless task and one is cheered to see there are some who take it on.

The urge to promote these alternative perspectives is to be found  across the Channel as well. There, a sub group of scholars and  nescafe society currently wished to form a separate group so that they may be evaluated by different norms.  Jean Tirole, in a letter to  the State secretary in charge of Higher education and Research in France, argued against this. A response can be found here.

Stanford University, based in California, has once again anticipated the future. In addition to providing subsidized housing to attract and retain faculty, faculty can now choose to be paid in water. The University has quietly been buying up farms to acquire ownership of water rights and has even signed futures contracts with the Great Lakes Regional Water authority for the delivery of water 15 years from now. In addition they have a joint venture with Elon Musk, to harvest water from comets. Google meanwhile, is behind the curve. They’ve only gone as far as allowing their employees to take long showers on site.

Having caught your eye, I direct you to an article in the April 9, 2015 edition of the Grey Lady. It discusses attempts by various countries to boost domestic birthrates. The same issue had been considered earlier by Noah Smith. There are two questions lurking here. First, what is the optimal population size for a country? If the goal was to shrink the population then a declining birth rate is not a bad thing. Suppose the goal is keep the population fixed, because, say of pension obligations. Then, one wants a replacement birth rate of roughly 2 per couple.

If the birth rate is below the target, what should one do? Interestingly, I cannot recall anyone I have asked or read who does not turn to Government interventions of various kinds. Noah Smith, for example, only discusses Government interventions before concluding one should imitate the French. If the birth rate is below what is optimal for society, why doesn’t the market take care of it?  Do we have a missing market? Is this a public goods problem? (If so, then, Mankiw who is often castigated for being a selfish beast, is, in this case, an unstinting provider of public goods, see here.)

Analogies are sometimes helpful (if biology is the study of bios, life; geology is the study of geos, earth, what does that make analogy?). Farmers plant crops and after a period, the fruits of their labor are harvested and sent to market.  The Farmer must anticipate what will be demanded in the future to decide what to plant now. What if she plants turnips when what is desired are parsnips? This problem is solved with a futures market for parsnips (or turnips or pork etc). Why not a futures market for babies? Those who want warm bodies in the future to support them in their dotage pay for babies now. Swiftian, I know, but interesting to consider. Once one thinks about how to implement the idea, difficulties emerge. One might, for example, be concerned with moral hazard on the part of parents. However, these same difficulties are present even with various Government subsidies.

According to the NY Times,  some Californians

would have to cut their water consumption by 35 percent under the terms of a preliminary plan issued by state officials on Tuesday to meet a 25 percent mandatory statewide reduction in urban water use.

There is an obvious way to achieve this, raise the price of water. If its obvious why isn’t it the first thing California did some years back when it was clear that water was scarce? In some cases the hands of the state are tied by water rights allocated for commercial purposes, so lets focus on household consumption.

We know that the first tool the state reaches for is regulation. See, for example, the following memo from the California State water board. Interestingly, it begins by noting that the state is in the 4th year of a drought! Eventually, it is clear that regulation is insufficient and then, price increases are considered. In fact, the water reduction targets quoted from the NY Times above come from a report by the Governor of the state that also urges the use of

rate structures and other pricing mechanisms

to achieve reductions. Again, why is price last rather first? Is this because the state must maintain a credible reputation for not exploiting its monopoly power with water?

If one is going reduce consumption by raising prices, should it be an across the board price increase? Note that consumption is metered so the exact amount that is purchased by a household is known to the provider. The state also has access to other information: location, home size, family size and income. In principle, the state could price discriminate. Here is an example from the Irvine Ranch Water district. Each household is given an initial `allotment’ that depends on household size and area that is landscaped. Exceed the allotment and the price of water rises. For more details and the impact on consumption see the following paper. Is it obvious that this is the `correct’ mechanism?

 

 

There is a brief period in a professor’s life when they are the lion of the dinner table and toast of the town. Its when the children of their friends and contemporaries are about to enter college. To my colleagues near and far I say enjoy the attention while you can.

What advice did I offer when called upon to do so?

Don’t worry. Your child has already made the most important decision of their lives and done so correctly. They chose you as a parent.

`No, seriously, how can my child make it to a top school?’, was the invariable reply. Followed by a reminder of the ostensibly low acceptance rates at `top’ colleges. `Don’t worry,’ I would repeat, `arithmetic is on your side.’

Each year about 30,000 students apply to Harvard. About 10,000 of these will be summarily rejected on academic grounds. That leaves about 20,000. Not all of them will get into Harvard. However, most of them are applying to the same subset of schools. There are 7 Ivy League schools, plus MIT, Stanford & Caltech. Throw in the University of Chicago and Berkeley. Collectively, these institutions enroll about 20,000 students in their freshman classes. This is not counting Duke, Northwestern, Michigan and UCLA.

`But, but, isn’t all that hard work, focus and diligence wasted if they don’t get into Stanford, MIT or Harvard?’

No, those habits will serve them throughout their lives not just at admission. Admissions is a lottery among those who make the `grade’. If the `losing ticket’ is Cornell or Chicago, its a lottery with no downside! How often does life present you with with such an opportunity.

Two articles in the March 3rd, 2015 issue of the NY Times. One by the columnist Nocera marvels at Buffet’s success and concludes that it must be due to Buffet’s genius. The second, in the business section of the same, summarizes Buffet’s annual letter that attempts to explain his success. As usual, neither considers the possibility that luck may have a role in Buffet’s success. Buffet may indeed be a Vulcan, but based on the data alone one cannot reject the possibility that luck may explain Buffet’s record. I won’t repeat the argument but will point to this paper by my colleagues (Foster & Stine) that does so.

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