On Fri, 22 Feb 2002 15:11:07 -0700 (MST) [EMAIL PROTECTED] wrote: > > > There isn't anything substantive here. . . > > Chris Auld
I think the point the article makes is an important one. In general, regardless of how sophisticated someone's econometrics work is, other economists almost always disbelieve the results if they conflict with their prior beliefs. If in the profession econometric studies are so unpersuasive, then why should the general public put any more credence in them? Daljit Dhadwal Here's a (long) excerpt from D. McCloskey's Summer 1994 article in the Eastern Economic Journal Why don't economists believe empirical findings? [He's writing about the bulletin from the Centre for Policy Research] . . . "But what surprised me is how uncommon the experience was and how often I doubted what my fellow scientists were earnestly telling me. The result of reading 44 pages of hundreds of scientific results from the front line of applied economics was mainly that I believed surprisingly little of it. The minuses and zeroes outnumbered the pluses. . . . Sometimes it contradicted itself, leading to indifference. Margaret Thatcher's reforms are said in successive sentences to have worked and to have not worked in raising British performance. Or on one page John Kendrick said that OECD countries converged after the War and on the next page Bart van Ark said they did not. Brief summaries, of course, can hardly do justice to a demonstration that the share of tradeables in Swedish national income has fallen, but on its face it's hard to believe, and I for one don't. No one really believes a scientific assertion in economics based on statistical significance. . . . I therefore am not being weird when I disbelieve the statistically significant finding that knowledge services (e.g. computer consultations) don't affect manufacturing productivity. . . . "I think you would have the same reaction. In fact I think you have it daily when you read the journals or listen to a colleague's talk or browse through the conference volumes produced by the Centre or the Bureau. Scientific results pour over you daily, but only a small percentage of them stick. Economists don't believe each other. "Now in a way this is not shocking. Most science has to be wrong or irrelevant, or else science would advance at lightening speed. It doesn't. The crystallographer and philosopher of science Michael Polanyi pointed out long ago that science supersedes itself and therefore most of what even the best scientists do will eventually be proven to be mistaken. As John Maddox, the editor of Nature, put it recently, "Journal editors, if they are honest with themselves, will acknowledge that much, perhaps most, of what they publish will turn out to be incorrect." "But I think it's worse in economics than in what we English speakers call "science." And I know it's worse than in historical science. Historians don't believe everything they read in the library. But they expect, rightly, to be able to rely on sheer factual assertions by their colleagues, and to have some confidence in their interpretations, if the signs of haste or of party passion are absent. (You can work out the signalling equilibrium here and make a pretty accurate prediction about what the profession of history is like.) "I would claim that in economics we have nothing like this degree of scientific agreement. To repeat, I don't believe it's merely a matter of my personal priors crashing up against the facts. You could put a minus sign in front of my priors and come to similar results. Most of the Bulletin, and most allegedly empirical research in economics, is unbelievable or uninteresting or both. It doesn't get down to the phenomena. It's satisfied to be publishable or clever. It's unbelievable unless you have to believe temporarily to get tenure. "The explanation is that economists when they write are tendentious. Good word, that: it means what we understand by "strong priors." Because they know always already (a useful phrase from German philosophy), they are not curious about the world. Contrast the books in history or biology or astronomy. The results come thick and fast and surprising. I read a book a while ago by E. C. Pielou called After the Ice Age: The Return of Life to Glaciated North America [Chicago University Press, 1992], and it was a page-turner, though it concerned three-spined sticklebacks and the East Coast refugia. Like economics, evolutionary biology and geology use stories constrained by simple principles of maximization. So why don't economists write books as gripping as Adrian Desmond's The Hot-Blooded Dinosaurs [Radius, 1990]? I have a British friend, Michael Summerfield, who is a geomorphologist . . . wrote a textbook, Global Geomorphology [Harlow, 1991], 537 big pages in double columns filled with fact and argument about the landscape, without a dull paragraph. Why? Because it's all about the world, and it's all documented and believable. It's motivated by curiosity (which is why a lot of economic history or legal economics is better economic science than most economics). "Other fields have the same problem. I suspect that physics, for all its prestige, has something like the same oversupply of dull or clever unbelievabilities. Anthropologists, who on the whole fear and loath economics and therefore never bother to learn any, seem at first more curious. But read anthropology that takes the journalistic book by Karl Polanyi in 1944 (Karl was Michael's less smart brother) as the last word on What Happened Under Capitalism and you'll find that they too are reading the world as they want it to read, tendentiously and therefore unbelievably. "Economists in other words are not curious enough to get their own data, talk to the economic actors, get right down into what is certainly the most interesting set of events in social life, the economy. They already know. How? This diagram on a blackboard. This clause in the platform of the Democratic Party. What economist do you know who has changed her mind? Bob Fogel has, four times. I have twice. Both are well above the mean and modal number of times, which is zero. But it's not a record of which either of us can be proud. "I think we should be worried that so much of economics is unbelievable tendentiousness. I think--don't you?--that economics ought to start getting serious about learning the economy. If even the Centre for Policy Studies, and the NBER, are going in circles, we've got a scientific problem."
