Let me begin by saying that I’m with the new Keynesians on the central issue here. I believe real world markets break down. A stunning point for me is the juxtaposition between the fact that much of modern macro began by trying to incorporate micro foundations into their models, but in the end, many of the proponents of the extreme version of fresh-water economics have ignored 30 years of micro that is pretty specific on all sorts of ways that markets can fail to clear.

That said, one can argue about the role of government on many levels. I take a variety of positions on these issues. I’m a deficit hawk, but a big believer in well-timed intervention. I’m in sympathy with the comment from our treasury secretary that we need to pay serious attention to the deficit, just not this year. I sure as heck hope he means the second part, though. The long chain of budget deficits forecast by the CBO scares the heck out of me.

Today, however, I want to make two reflections on the right form of stimulus.

The first is an easy one. In talking about the purported wastefulness of direct stimulus spending, I think it is well worth noting that very few people would argue that this country has been spending too much on infrastructure. Clearing up a lot of deferred maintenance seems like a fine idea to me, and getting our transportation system back up to something approaching the quality viewed as normal in much of the developed (and developing) world a pretty good idea too. For much the same reason, I get less worked up than many about “pork-barrel” spending; sure, it would be nice to have a more transparent process, and maybe doing a little better on allocating scarce resources on the margin, but we seem so far from a sensible amount of public goods in this country that I’m doubtful that much of the spending is truly a waste.

Now to my second, and maybe less trivial point about stimulus spending. One theme that has recurred in left-of-center blog land of late is that if only we could have another round of “real” stimulus, we wouldn’t need to be doing back door stuff like cash for clunkers and the tax subsidy for home purchasers. I disagree! If one wants to stimulate economic activity at reasonable cost, this seems like a good way to go. Why? Because it is pulling exactly the right lever if you think hard about why spending has fallen in the first place.

One reason, of course, is because some people have less money. Extending unemployment insurance benefits seems a good idea in this context. State governments, many of which have mandatory budget balance mechanisms, are also in the class of entities to which  a direct cash transfer is likely to stimulate spending.

But, the bulk of the reduction in spending, by both firms and consumers, is not “we have no money to spend, or nothing worth spending it on”. Rather, they are properly exercising option value in a setting of wildly increased uncertainty. In the months after the financial meltdown, a new TV suddenly needs to meet a much higher hurdle: the question is not “do I think the flow of services from the TV over the next 8 years is more than worth the cost”, but “do I expect to derive enough value from owning this TV now instead of 3 months from now that I wouldn’t rather wait a bit, and see how the situation develops.” If things look less apocalyptic in three months, one can always buy the TV then, having foregone only a few months of HDTV heaven. On the flip side, if in three months the situation has shifted for the worse, then one has avoided being saddled with a TV/car/house/factory that does not make sense in the new environment.

If I’m waiting to buy a new house because I’m waiting to see if I get tenure, this delay is economically efficient. But, if the uncertainty is aggregate and extreme, so the we all want to exercise the option value of delay, and if one believes that markets don’t always clear, then if we all start delaying economic activity because we want to see if the future is bad, the future has a decent chance of being just that.

In such a context, a tax cut, or a check from the government, is likely to have very little effect. I’m a little more flush than I was (although I’m also guessing that my future tax liability is going to be higher), but heck, I had money to spend before anyway. If the issue is uncertainty, then the right thing to do with extra money that appears is to simply stick it in the bank.

On the other hand, if the choice is “new car today at huge discount” vs. car in 3 months at normal prices, then I may well pull the trigger even if I face a moderate degree of uncertainty. Note then, though, that cash for clunkers and the housing subsidy are particularly effective precisely to the extent that people think they will end. If I am pretty sure the program will be renewed, then the original calculation is back in effect, and waiting is probably the right thing to do.

This brings us to one of the most important points made by Lucas, Phelps, and company: economic policy based on consistently fooling people is unlikely to be a great idea. Here, the problem is to avoid the temptation to go back and re-new each program as it nears expiration. If people grow to expect this, they lose their oomph.

This has been illustrated in a paper by Megan Busse, Duncan Simester, and Florian Zettelmeyer. In the wake of 9/11, GM ran “The best deal you’ll ever get.” Precisely because it had a well-defined end date, and one that seemed credible given the extraordinary circumstances, the program was extremely effective in raising sales for GM despite the uncertainty rampant that fall. But, when GM renewed it, the effect was much smaller, probably because people no longer saw the cost of delay as being large.