Tale dva zapisa od Krugmana sta “obvezno branje” za tiste, ki bi radi vedeli, kdaj in zakaj se je zgodila “državljanska vojna v ekonomiji” oziroma “Veliki razkol” (saltwater/freshwater oziroma neokeynesianizem/neoklasika). Gre za to, ali imajo nominalni šoki lahko realne posledice oziroma ali na ekonomsko aktivnost vpliva šok v agregatnem povpraševanju (padec povpraševanja) ali realni šok (tehnološke spremembe). In še bolj preprosto, gre za fundamentalno vprašanje: zakaj v času krize plače in cene ne padejo (kot predvidevajo modeli)? (Če plače ne padejo, morajo podjetja odpuščati, da prilagodijo stroške manjšemu povpraševanju, kar ustvari brezposelnost, ki pa je modeli, ki temeljijo na racionalnih pričakovanjih ne predvidevajo)
Tja, za neakademske ekonomiste je to najbrž brezvezna debata, toda na žalost je še kako pomembna, saj je vplivala na smer razvoja ekonomije in na to, kako modeliramo gospodarstvo, ali znamo napovedati gospodarske šoke ter ali znamo izbrati prava “zdravila” (ukrepe), ko se krize zgodijo. Če bi imeli manj enostransko mainstream ekonomijo, tega petletnega tavanja ekonomske politike, kot ga opazujemo, ne bi bilo.
So, if you had to choose a beginning, it would be the famous Phelps volume. The papers in that volume all started with two observations, of which the first was that there was overwhelming evidence for some kind of short-run non-neutrality of money. … But as the papers also observed, it was hard to explain that fact in terms of standard microeconomics: with everyone acting rationally, money should have been neutral even in the short run. Traditional Keynesian analyses simply said that people aren’t completely rational, that they have money illusion – or maybe that contracts are focal points in which nominal wages or prices matter because of salience, even though they should be arbitrary. But these were ex post rationalizations rather than being derived from some kind of fundamentals.
So the Phelps crowd came up with a lovely story: you see, it was all about information. Individuals and firms couldn’t tell, in the very short run, whether a rise in the price they were being offered represented a shock specific to them – people for some reason wanted more of their widgets — or a general change in demand. It was rational to respond to an idiosyncratic rise in demand by producing more, so confusion could explain why short-run aggregate supply seemed upward-sloping.
But here’s the thing: after that initial success, Phelps-Lucas/type microfoundations quickly collapsed both intellectually and empirically. Intellectually, the problem was that rational individuals simply should not have been confused in the way the models demanded; there’s too much information out there, whether in newspapers or in asset prices. You just couldn’t get a Lucas supply curve out of a model looking even vaguely like the real economy.
Empirically, the problem was that slumps last too long. Even if you wave away the information problem, confusion about aggregate versus idiosyncratic shocks can last for quarters, maybe, but not years.
Preberite več v Paul Krugman, Microfoundations and the Parting of the Waters
Well, back in the 1990s the economist Truman Bewley — an economist heretofore known for high theory in microeconomics — did something novel on the subject of wages, and why they don’t fall in recessions: he went out and asked people. And what he found was that issues of fairness and morale were key. Employers didn’t cut wages, even when unemployment was high and they knew that employees had no place to go, because they believed that morale and workplace cooperation would collapse if their employees felt that the company was exploiting a bad economy for its own gain.
The parallel should be obvious — and of course it’s a lot more important to feel that your employer won’t betray you than it is to feel good about your car service.
Is there a rigorous way to model this kind of behavior? Not yet. Someday, one suppose, we’ll be able to put it all in equations — after all, everything is quantum mechanics in the end. But two things are certain right now. One is that this kind of thing really happens; the other is that it can’t be derived from the narrow notion of maximization that underlies what passes for “microfounded” macroeconomic models in the early 21st century.