I can envision a pure barter economy with incorrect price expectations in which individual plans are in a state of discoordination. Or consider a Fisherian debt-deflation economy in which debts are denominated in terms of gold and gold is appreciating. Debtors restrict consumption not because they are trying to accumulate more cash but because their debt burden is so great, any income they earn is being transferred to their creditors. In a monetary economy suffering from debt deflation, one would certainly want to use monetary policy to alleviate the debt burden, but using monetary policy to alleviate the debt burden is different from using monetary policy to eliminate an excess demand for money. Where is the excess demand for money?
Evidently, Scott doesn’t quite find my argument that coordination failures are possible, even without an excess demand for money, persuasive. So he puts the following question to me.
Why is it different from alleviating an excess demand for money?
I suppose that my response is this is: I am not sure what the question means. Does Scott mean to say that he does not accept that in my examples there really is no excess demand for money? Or does he mean that the effects of the coordination failure are no different from what they would be if there were an excess demand for money, any deflationary problem being treatable by increasing the quantity of money, thereby creating an excess supply of money. If Scott’s question is the latter, then he might be saying that the two cases are observationally equivalent, so that my distinction between a coordination failure with an excess demand for money and a coordination failure without an excess demand for money is really not a difference worth making a fuss about. The first question raises an analytical issue; the second a pragmatic issue.
As far as I know the demand for money is usually defined as either M/P or the Cambridge K. In either case, a debt crisis might raise the demand for money, and cause a recession if the supply of money is fixed. Or the Fed could adjust the supply of money to offset the change in the demand for money, and this would prevent any change in AD, P, and NGDP.
I don’t know what Scott means when he says that the demand for money is usually defined as M/P. M/P is a number of units of currency. The demand for money is some functional relationship between desired holdings of money and a list of variables that influence those desired holdings. To say that the demand for money is defined as M/P is to assert an identity between the amount of money demanded and the amount in existence which rules out an excess demand for money by definition, so now I am really confused. The Cambridge k expresses the demand for money in terms of a desired relationship between the amount of money held and nominal income. But again, I can’t tell whether Scott is thinking of k as a functional relationship that depends on a list of variables or as a definition in which case the existence of an excess demand for money is ruled out by definition. So I am still confused.
I agree that a debt crisis could raise the demand for money, but in my example, it is entirely plausible that, on balance, the demand for money to hold went down because debtors would have to use all their resources to pay the interest owed on their debts.
I don’t disagree that the Fed could engage in a monetary policy that would alleviate the debt burden, but the problem they would be addressing would not be an excess demand for money; the problem being addressed would be the debt burden. but under a gold clause inflation wouldn’t help because creditors would be protected from inflation by the requirement that they be repaid in terms of a constant gold value.
Perhaps David sees the debt crisis working through supply-side channels—causing a recession despite no change in NGDP. That’s possible, but it’s not at all clear to me that this is what David has in mind.
The case I had in mind may or may not be associated with a change in NGDP, but any change in NGDP was not induced by an excess demand for money; it was induced by an increase in the value of gold when debts were denominated, as they were under the gold clause, in terms of gold.
I hope that this helps.
PS I see that Nick Rowe has a new post responding to my previous post. I have not yet read it. But it is near the top of my required reading list, so I hope to have a response for him in the next day or two.