On Fri, 22 Feb 2002 15:11:07 -0700 (MST) [EMAIL PROTECTED] wrote:
>
>
> There isn't anything substantive here. . .
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> 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 believa
