Tuesday, August 30, 2011

Easychair never forgets!

When I log on to Easychair and select “My conferences” it returns a list of thirteen conferences (going back to 2007) with which I’ve been involved with in various capacities. If you were chair, you get to see everything that was submitted, and what the reviews were. A PC member can see all submitted papers, and discussions on the papers he/she was assigned. For some conferences, it seems like a PC member can in fact see the reviews of all papers; I guess it depends on what settings were originally chosen by the chair. Thus, if you submit a flakey paper to a conference that used easychair, and you got a well-deserved rejection, it remains possible for various people to log on subsequently and roar with laughter as they review your ineptitude.

Actually I quite like easychair; I even like the fact that it’s possible to dig up some vaguely-recalled paper that you reviewed in the past. But it may be a matter of concern to some people. It seems like the chair(s) of a conference/workshop can delete any submissions to that meeting, but I don’t see an obvious facility for cleanly closing the book on discussions that have served their purpose. My question: does anyone think it’s a problem that all those rejected papers and discussions continue to be available, year after year?

Saturday, August 20, 2011

Disappearing money

This post relates to a minor gripe about academic life, and since it has not arisen for me very recently, now is a good time to air it. While money always tends to disappear, there’s a certain kind of money that disappears automatically, much like the leprechaun gold in Harry Potter. By way of example, some time ago I had some cash, or rather my employer owned the cash on my behalf, and it was available to be spent on business travel or equipment. Then one day my employer said: you must spend it all by such and such a date, after which you lose the money1. So, I bought a laptop that I didn’t really need, and underused it subsequently. The result of slapping a use-by date on the money was that it was used less effectively.

A colleague of a colleague (OK, this is like “friend of a friend” but never mind) had to urgently find a PhD student to fill a place he or she had; due to time pressure the CoaC would accept even a weak candidate. More time would presumably let the CoaC find a stronger candidate. Funding agencies impose onerous time constraints on grants — researchers rush to spend against grants that are about to expire, or make suboptimal hiring choices due to time limits.

This is not to argue that funds should be held by researchers on a completely open-ended basis. Presumably such funds were awarded at a time when there was evidence that the researcher would use them effectively, and the longer you wait, the less certainty there is that the usage will be effective. But there is scope for discussion about the length of deadlines, which would probably result in longer deadlines. Better yet would be an acknowledgement that these kind of deadlines result in an unnecessary all-or-nothing situation, where there is scope instead for a smooth transition between one extreme and the other. An institution could tax unspent money at some fixed rate, if inflation is not depreciating it fast enough. How about using Chiemgauer notes... see this recent article in the FT, or from this web page:
The "Chiemgauer" currency (named for the Bavarian region of Chiemgau) is the most successful to date. The project was started by Christian Gelleri, a Waldorf school teacher, and six of his students in Bavaria in 2002. The regional currency's annual turnover climbed to an impressive €1.5 million ($2 million) last year. About 90,000 Chiemgauers are currently in circulation. Unlike the Urstromtalers, they can be converted back into euro for a fee. "Our currency circulates three times more rapidly than the euro," says Gelleri. But in order to achieve this, the system puts pressures on currency holders to spend: The Chiemgauer loses two percent of its value every three months and has to be "topped up" by purchasing a coupon.

The idea for a so-called "depreciative currency" was pioneered by Silvio Gesell, a German merchant and social reformer. Gesell witnessed a serious economic crisis in Argentina at the end of the 19th century. He explained it in terms of excessive hoarding and insufficient monetary circulation. His solution was to make money perishable like other commodities -- bank notes, he believed, should "rust."

There’s an analogy with the way we impose deadlines on students to hand on coursework. There are two ways to penalise students who are late, both of which I have experienced. One of them is to give them zero credit if they miss the deadline. The other way to penalise at the rate of (say) 5% per day of lateness. Of course, the first of these leads to tedious disputes about whether a coursework submission should be deemed to be handed in on time. Under the second regime, if a student is slightly late and has a weak excuse, he takes the 5% penalty and hopefully notes that the way to be sure to make a deadline is to get the work done some time in advance, without getting pushed into making excuses in order to avoid wasting the work he wanted to turn in.

1Of course, it doesn’t really vanish; it reverts to the employer/funder, which hopefully puts it to some good use. But there’s a widespread —and rather regrettable— attitude that it vanishes entirely.

Thursday, August 18, 2011

Staying connected

I did not write any email during a vacation over the last 10 days. I occasionally checked my inbox for messages of the reply-to-this-or-you’re-fired variety, and so watched the inbox backlog build up, with the same kind of gruesome fascination with which I watched the stock market. Is this failure to reply to emails in violation of a social convention? Plenty of academic colleagues seem to send email while on holiday, but I reckon it’s a behaviour that’s fairly specific to academics.

In support of answering emails while on vacation, is the notion that you let the world know that you’re a virtuous workaholic, and (by being online at all hours) a truly modern academic. In opposition, there’s the point that we end up cultivating the expectation that we answer emails promptly, without in fact gaining any credit for workaholism. Email gets in the way of deep thought. I know one distinguished academic — now retired — who insists that he got all his best ideas while holed up in his vacation retreat, since it had no telephone. Also, while the post-vacation hangover is no doubt painful, email is most efficiently dealt with in batch mode rather that on-line. Indeed, some of the problems that were emailed to me had fixed themselves before I had time to assist (some feedback forms were lost, then found, for example), and some of the documents colleagues sent me got superseded by later versions that were re-sent a few days later. Finally, by ignoring your inbox you take a valiant last stand against the fate of being a truly modern academic.

(added later:) Recent article on “worliday” — not sure the word will catch on though.

Friday, August 05, 2011


I went along to some talks at ICEC 2011 here at Liverpool, including an interesting invited talk by Robert May on Stability and Complexity in Banking Ecosystems, along with some others in the general area of agent-based computational economics (ACE). A lot of this research is experimental: you set up a virtual marketplace along with traders who compete in it, then “The modeler then steps back to observe the development of the system over time without further intervention” (to quote the wikipedia page).

Of course, current economic problems serve to motivate this topic a great deal and perhaps will cause it to attract a bigger share of research funds, over the next few years. Robert May's talk reported on some experiments involving models of interbank lending aimed at predicting the spread of bank failures, along with some basic (by the standards of most theory people, I would guess) calculations of how the probability of systemic failure is affected by the extent to which banks diversify their assets. Another talk that I went to, compared two markets in which traders bought and sold a single good: one version was a centralised market in which a single price was maintained, while the other version worked by bringing together pairs of traders at random, and a trade would go ahead if the trader with higher value, could afford to buy from the other one. The latter version does not perform “price discovery” so effectively, since trades can take place at the same time at different prices, but there’s apparently a sense in which it’s more stable. Also, incompetant traders get “weeded out” in the decentralised version since they get ripped off, while in the centralised version they can free-ride on the wisdom of the crowd, due to the single current price. You may or may not consider that to be a good thing. The trading strategies were produced by some kind of evolutionary algorithm in which the poorly-performing ones get eliminated while the good ones prevail (and maybe get mutated, I can’t remember).

I would conjecture that there is scope for the theory community to contribute to this research area, somewhat by analogy to Ingo Wegener’s work on genetic programming: genetic and evolutionary algorithms was purely experimental, and he and co-workers contributed the first proofs of performance guarantees for some of these. Such a contribution could help to guide experimental design in computational economics, or address concerns about the realism of the models used in simulations.

Here is a video of an earlier similar talk by Robert May.