The Role of Monetary Policy, Revisited

I am giving a talk Thursday May 30, titled  "The Role of Monetary Policy, Revisited."  The event is at Booth's Gleacher Center in downtown Chicago, reception 4:30 and talk 5:15. It's part of a series of talks sponsored by the Becker-Friedman Institute.

The talk is based on  an essay I'm working on, and will be presenting at a few central banks this summer. Once per generation we re-think what central banks do, can't do, should do, and shouldn't do. Milton Friedman's famous 1968 address marked the last big transition. I think, we are in a similar moment. I will look at the big picture in the same spirit. I'm aiming at a serious talk, grounded in academic research, but accessible.

Blog followers, students, colleagues, friends, and even glider pilots are most welcome. Please rsvp so they know how many people to plan for.

The event announcement invitation and rsvp links are here on the BFI webpage

There is also an event announcement and rsvp link on the Booth Alumni events webpage here.

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The Becker Friedman Institute for Research in Economics of the University of Chicago cordially invites you to The Role of Monetary Policy Revisited A talk by John H. Cochrane, AQR Capital Management Distinguished Service Professor of Finance at the University of Chicago Booth School of Business Thursday, May 30, 2013 4:30 p.m. Reception 5:15 p.m. Talk and Q&A Executive Dining Room, Sixth Floor University of Chicago Gleacher Center 450 North Cityfront Plaza Drive Chicago, Illinois (map and directions) Please join us as University of Chicago Booth School of Business Professor John Cochrane reexamines Milton Friedman's 1968 presidential address to the American Economic Association. In this famous speech on the role of monetary policy, Friedman argued, "There is always a temporary trade-off between inflation and unemployment; there is no permanent trade-off." Starting from this perspective, Cochrane will reevaluate the role of monetary policy 45 years later. Is it effective? Can it fill all the roles people expect of it? How should monetary policy be conducted going forward? RSVP Please respond online by May 23. Please extend this invitation to others who might find the program of particular interest. Complimentary valet parking will be available at the Gleacher Center entrance. QUESTIONS If you have questions or require advance assistance, please contact Maria Bardo-Colon at 773.834.1898 or bfi@uchicago.edu. John H. Cochrane The AQR Capital Management distinguished service professor of finance at the University of Chicago Booth School of Business, Cochrane's scholarly work focuses on finance, monetary economics, macroeconomics, health insurance, time-series econometrics, and other topics. He is the author of Asset Pricing, a coauthor of The Squam Lake Report, a research associate of the National Bureau of Economic Research, a senior fellow of the Hoover Institution at Stanford University, and an adjunct scholar of the CATO Institute. He blogs as The Grumpy Economist. Cochrane earned a bachelor's degree in physics at Massachusetts Institute of Technology and PhD in economics at the University of California, Berkeley. He was a member of the University of Chicago Department of Economics before joining Chicago Booth.

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More Interest-Rate Graphs

For a talk I gave a week or so ago, I made some more interest-rate graphs. This extends the last post on the subject. It also might be useful if you're teaching forward rates and expectations hypothesis. 

The question: Are interest rates going up or down, especially long term rates?  Investors obviously care, they want to know whether they should put money in long term bonds vs. short term bonds.  As one who worries about debt and inflation, I'm also sensitive to the criticism that market rates are very low, forecasting apparently low rates for a long time. Yes, markets never see bad times coming, and markets 3 years ago got it way wrong thinking rates would be much higher than they are today (see last post) but still, markets don't seem to worry.

But rather than talk, let's look at the numbers. I start with the forward curve. The forward rate is the "market expectation" of interest rates, in that it is the rate you can contract today to borrow in the future. If you know better than the forward rate, you can make a lot of money.

Here, I unite the recent history of interest rates together with forecasts made from today's forward curve. The one year rate (red) is just today's forward curve. I find the longer rates as the average of the forward curves on those dates. Today's forward curve is the market forceast of the future forward curve too, so to find the forecast 5 year bond yield in 2020, I take the average of today's forward rates for 2020, 2021,..2024.

I found it rather surprising just how much, and how fast, markets still think interest rates will rise. (Or, perhaps, how large the risk premium is. If you know enough to ask about Q measure or P measure, you know enough to answer your own question.)


How can the forecast rise faster than the actual long term yields? Well, remember that long yields are the average of expected future short rates, and if short rates are below today's 10 year rate for 5 years, then they must be above today's 10 year rate for another 5 years. So, it's a misconception to read from today's 2% 10 year rate that markets expect interest rates to be 2% in the future. Markets expect a rise to 4% within 10 years. 

The forward curve has the nice property that if interest rates follow this forecast, then returns on bonds of all maturities are always exactly the same. The higher yields of long-term bonds exactly compensate for the price declines when interest rates rise. I graphed returns on bonds of different maturities here to make that point.

So, Mr. Bond speculator, if you believe the forecast in the first graph, it makes absolutely no difference whether you buy long or short. Otherwise, decide whether you think rates will rise faster or slower than the forward curve.

Now, let's think about other scenarios. One possibility is Japan. Interest rates get stuck at zero for a decade. This would come with sclerotic growth, low inflation, and a massive increase in debt, as it has in Japan. Eventually that debt is unsustainable, but as Japan shows, it can go on quite a long time. What might that look like?

Here is a "Japan scenario." I set the one year rate to zero forever. I only changed the level of the market forecast, however, not the slope. Thus, to form the expected forward curve in 2020, I shifted today's forward curve downwards so that the 2020 rate is zero, but other rates rise above that just as they do now.

This scenario is another boon to long term bond holders. They already got two big presents. Notice the two upward camel-humps in long term rates -- those were foreasts of rate risks that didn't work out, and people who bought long term bonds made money.

In a Japan scenario that happens again. Holders of long-term government bonds rejoice at their 2% yields.  They get quite nice returns, shown left, as rates fail to rise as expected and the price of their bonds rises. Until the debt bomb explodes.

OK, what if things go the other way? What would an unexpectedly large rise in interest rates look like? 
For example Feburary 1994 looked a lot like today, and then rates all of a sudden jumped up when the Fed started tightening.  

To generate a 1994 style scenario from today's yields, I did the opposite of the Japan scenario. I took today's forward curve and added 1%, 2%, 3% and 4% to the one-year rate forecast. As with the Japan scenario, I shifted the whole forward curve up on those dates. We'll play with forward steepness in a moment.

Here are cumulative returns from the 1994 scenario. Long term bonds take a beating, of course. Returns all gradually rise, as interest rates rise. (These are returns to strategies that keep a constant maturity, i.e. buy a 10 year bond, sell it next year as a 9 year bond, buy a new 10 year bond, etc)

These have been fun, but I've only changed the level of the forward curve forecast, not the slope. Implicitly, I've gone along with the idea that the Fed controls everything about interest rates. If you worry, as I do, you worry that long rates can go up all on their own. Japan's 10 year rate has been doing this lately. When markets lose faith, long rates rise. Central bankers see "confidence" or "speculators"  or "bubbles" or "conundrums." What does that look like?

To generate a "steepening" scenario, I imagined that markets one year from now decide that interest rates in 2017 will spike up 5 percentage points. This may be a "fear" not an "expectation," i.e. a rise in risk premium.

Then, the 5 and 10 year rates rise immediately, even though the Fed (red line) didn't do anything to the one-year rate. The bond market vigilantes stage a strike on long term debt.

Here are the consequences for cumulative returns of my steepening scenario. The long term bonds are hit much more than the shorter term bonds. This really is a bloodbath for 10 year and higher investors, leaving those under 5 years much less hurt.

So what will happen? I don't know, I don't make forecasts. But I do think it's useful to generate some vaguely coherent scenarios. The forward curve is not a rock solid this is what will happen forecast. The forward curve adds up all of these possiblities, with probabilities assigned to each, plus risk premium. There is a lot of uncertainty, and good portfolio formation starts with risk management not chasing alpha.

Debt and growth in 10 minutes

This is a short video from last year. I only just found out it exists. It still seems pretty topical, and (for once) condensed because Lars Hansen really forced me to obey the 10 minute time limit!

There is a better link here from the BFI page here that covers the whole event, but I couldn't figure out how to embed those.

Buffett Math

Warren Buffett, New York Times on November 25th 2012:

Suppose that an investor you admire and trust comes to you with an investment idea. “This is a good one,” he says enthusiastically. “I’m in it, and I think you should be, too.”

Would your reply possibly be this? “Well, it all depends on what my tax rate will be on the gain you’re saying we’re going to make. If the taxes are too high, I would rather leave the money in my savings account, earning a quarter of 1 percent.” Only in Grover Norquist’s imagination does such a response exist.

MBA final exam question: Explain the mistake in this paragraph.

How do we decide whether to invest in a project?  Discounted cash flow.

For example, suppose you’re thinking of building a factory (or starting a business). Once built, your best guess is that the factory will produce $10 profit every year. Discounting at a 5% required return, typical of stock market investments, the value of that profit stream is 1/.05=20 times the yearly profit, or $200. If the factory costs $150 to build, it’s a good deal and will return more than its costs. You build it. If the factory costs $250 to build, you walk away.

Did you forget to put in after-tax cash flows? Whoops, that's a B- now at best. For example, if the tax rate is 50%, then your after-tax profits are only $5 each year. Now the value of the profit stream is only $100. The factory still costs $150 to build however, so now you’d be a fool to do it. It truly is better to leave your money in the bank earning a quarter of a percent.

Mr. Buffett made an elementary accounting mistake. How did he get it wrong? Implicitly, he is thinking that he pays $100, then gets back $100 for sure, and only the profit is taxed. He's thinking that a 5% rate of return gets cut to 2.5%, which is still better than 0.025%. But when you build a factory or start a business, you are not guaranteed return of principal. You only get the profits, if any. If the government taxes half the profits, that’s like taking half the initial investment away.

This is perhaps an understandable mistake for a financial investor such as Mr. Buffett. In my example, the market value of the factory was $200, and falls to $100 when the tax is imposed. Mr. Buffett doesn't build factories or start businesses, he buys them.  Now, Mr. Buffett -- ever the "value" investor -- can swoop in, buy the factory for $100, and a $5 per year after-tax cashflow generates the same 5% rate of return. But nobody will build new factories, and that’s the economic damage.

Ok, now you get an A. Let's go for the A+.

Mr Buffett ignored risk. If somebody offers you a 5% rate of return, risk free, when Treasury bills offer you a quarter of 1 percent, his name is Madoff, not Buffett-Buddy.

Mr. Buffett wants you to think his investments are arbitrage opportunities, and a 2.5% arbitrage is as attractive as a 5% arbitrage. That's false. Investments involve bearing risk, and taxes make those investments directly worse.

Now, the effect of taxes here is subtle. Yes, a 50% tax rate cuts a 5% expected return down to 2.5%. But it also cuts volatility too. Isn't this just like deleveraging? Answer: no, because unless you're investing in green energy boodoggles only available to Administration cronies, the government takes your profits, but does not reimburse your losses.

If the investment makes 10%, you get 5%. If it makes 5%, you get 2.5%. But if it loses 10%, you lose 10%. It's a strictly worse investment when taxed. (Yes, you might be able to sell the losses if the IRS doesn't notice what you're up to... but now you know why Buffett is a "master of tax avoidance.")

And there is always another margin: If rates of return on investment look lousy, just stop investing at all and go on a consumption binge. The estate tax is a big subsidy to the round-the-world cruise and private jet industries. 

I am really amazed by how this argument has evolved. Only a few months ago, supporters of the Administration's plans for higher tax rates admitted the plain fact that higher tax rates on investment are bad for growth. But, they argued that higher taxes would be good for other goals, like "fairness," redistribution, or winning elections important for other policies they like such as ACA. (These taxes are not going to put a dent in the deficit.)  And we had a sensible argument about how bad the growth effects would be, and how long it would take for them to kick in.

Now they're trying to argue that taxes aren't bad for the economy at all.  Some are suggesting higher investment tax rates are actually good for the economy.  All in the face of the natural experiment playing out in front of us across the Atlantic. The contortions needed to make this argument are just embarrassing. As above.

It seems clear to me that the Administration wants to raise the tax rate on high income people for political reasons, whether or not they raise tax revenues from such people; witness the deafening silence about reforming the chaotic tax code. The Buffetts of the world who can exploit the loopholes in the tax code and lobby for more will do fine in the new world. But they shouldn't stoop to such obvious silliness to try to fool the rest of us that pain don't hurt.

(Thanks to Cliff Asness who brought this to my attention and suggested some of the arguments.)

Unraveling the Mysteries of Money

Harald Uhlig and I did a fun interview run by Gideon Magnus (Chicago PhD) at Morningstar. We talk about the foundations of money, fiscal theory, monetary policy, European debt problems, etc. Gideon framed it well, and Harald is really sharp. Somebody combed my hair. A cleaned up version of the interview appeared in the Morningstar Advisor Magazine (html) (A prettier pdf)



A link in case the video doesn't work or doesn't embed well (if you see "server application unavailable" the link usually still works), or if you want the original source.

The video starts a little abruptly, as it left out Gideon's thoughtful introduction (it's in the Magazine) and framing question:

Gideon Magnus: I want to discuss the value of money and the idea that money is valued similarly to any other asset. Are there really assets backing money? If so, what are they? John, please explain.

Price and volatility in the great crash

I made the following cool graph last week. (Well, I think it's cool):

The black line is the VIX volatility index. You can think of it as a market forecast of volatility over the next month. It starts at about 25, reflecting a 25% per year standard deviation of stock returns. In the financial crisis, it shoots up to 80%. Yes, 80% annualized standard deviation. Then it tails back again with another jump in early 2010. (The VIX tracks realized volatility almost perfectly in this episode, so it's not about volatility risk premiums.)

The blue line is the cumulated return on the Fama-French total stock market index. (Data from Ken French's website.)  If you had a dollar in the market in January 2008, it shows you the percent gain or loss through time. (The level of the S&P500 shows almost exactly the same pattern.) That's also pretty dramatic: you lose half your money by March 2009, before the market recovers.

The negative correlation between these two lines is striking. Yes, we've known for a long time that lower prices are associated with higher volatility, but it's not often that you see such a striking correlation.

What do we make of it? It seems to revive the idea that mean returns and volatility are related. If volatility goes up, then mean returns must go up too, so that the average investor keeps holding the market portfolio. The only way for mean returns to go up is for the price to decline. You can almost blame the fall in prices on the rise in volatility.

The challenge is to get the numbers to add up.  The standard portfolio allocation rule says

share in risky assets = 1/(risk aversion) x mean return / variance of return

Variance is volatility squared, so if volatility goes from 20 to 80, the denominator rises by a factor of 80^2/20^2= 16!  If you have all your money in stocks, share = 1, we need the mean also to rise by a factor of 16; say from 6% to nearly 100%. Did  participants expect the entire 50% stock market decline to be reversed in 6 months? I've written about time-varying expected returns, but even for me a market risk premium of +100% seems like a lot.

I think the answer is, this is the wrong equation. It's time to get serious about Merton portfolio theory for long-lived investors. The real (Merton) portfolio theory adds to the last equation

... + (aversion to volatility risk) x (covariance of return with changes in volatility)

So, something about this term must be screaming "get in" to counteract the last equation's advice to "get out."  Why do people care about volatility risk? ("aversion") Why does this term vary strongly over time?

Something in this event seems to be crying to explain "state variable risk" in an intuitive way, but doing so is just out of my reach. (I've been puzzling about this for a while, see p. 1082 of "Discount Rates". )

Of course, volatility is not the ultimate "state variable," and understanding the movement of stock prices will eventually means we need to dig deeper to underlying events. 

Context: I was discussing two nice papers at the NBER asset pricing meetings:  "Volatility, the Macroeconomy and Asset Prices,  by  Ravi Bansal, Dana Kiku, Ivan Shaliastovich, and Amir Yaron, and  "An Intertemporal CAPM with Stochastic Volatility" by John Y. Campbell, Stefano Giglio, Christopher Polk, and Robert Turley.  Both papers explore  time-varying volatility and attempt to answer this puzzle. (Google for latest versions of the papers.)

Cambpbell et. al. also argue that the value effect (higher returns for value stocks than growth stocks) is explained by value stock's tendency to move with changes in volatility.  That's why I included the value stock cumulative return in the graph.

Update

Pedro Santa-Clara sent this graph:

It shows a nice correlation between the VIX and the earnings/price ratio. In turn, the earnings/price ratio is one of the best return forecsaters. So, conditional mean and conditional variance of returns do move together.

That's nice, as it sometimes seems that volatility and mean return wander off in different directions, in response to different state variables, and at different frequencies. A united view of the two moments is essential.

But don't get too exited. The graph certainly does not document a constant Sharpe ratio, or even a constant mean to variance ratio. The earnings yield corresponds roughly 1 to 1 ("roughly" means between 1 to 1 and 1 to 3) with one-year expected returns, so you're seeing expected returns vary roughly from 4 to 7 percent. The VIX is moving orders of maginitude more. So one-year Sharpe ratios and mean/variance ratios are still moving a lot over time! But perhaps we can coalesce the state variables somewhat, and find common factors in conditional mean and variance. 

Japan

I'm in Japan, one great data point on the ineffectiveness of fiscal stimulus, and the reason for blog silence for the last week or so. I will be giving a talk about asset pricing, based on the "Discount Rates" paper, at a Chicago Booth  event on Friday evening March 23 at the American Club in Tokyo, details here. Blog readers and ex-students most welcome. It's a public event, but you have to register.  

All the world's troubles in 10 minutes

Last month, John Taylor asked me to give some  lunch-time remarks at a conference on "Restoring Economic Growth" at the Hoover institution. "Oh," said John, "Just talk about what's going on in Europe and how to fix the U.S. economy. Keep it to about 10 minutes." As any economist knows, it's easy to talk for an hour and nearly impossible to talk for 10 minutes. Then I looked at my fellow panelists, who turned out to be George Schultz and Alan Greenspan. Heady company, I feel like a kid again.

The euro crisis,some emerging thoughts on how to create a run-free financial system, a review of why everything on the current policy agenda does not have a prayer of working, and a note of cation to economists'  collective habit of jumping from bright idea to policy. (There is a permanent version on my webpage)

In case you’re not reading the papers, we’re in financial crisis 3.0, a run on European banks stemming from their sovereign debt losses.

This is not high finance. European banks have been failing on sovereign debt since Edward III stiffed the Perruzzi in 1353. This is not a “multiple equilibrium,” a run of self-confirming expectations. People are simply getting out of the way of sovereign default, since it’s pretty clear that governments are at the end of the bailout rope.

By dutiful application of bad ideas and wishful thinking, the Europeans have turned a simple sovereign restructuring into a currency crisis, a fiscal crisis, a banking crisis, and now a political crisis. They could have had a lovely currency union without fiscal union. The meter in Paris measures length. The Euro in Frankfurt measures value. And sovereigns default, just like companies. They could do what George Schulz beautifully called the “simple obvious” things, and return to the kind of strong growth that would let them pay off large debts. Alas, the ECB is full in, both buying debt and lending to banks who buy debt, so now a sharp euro inflation – which is just a more damaging and wider sovereign default -- seems like the most likely outcome.

How did we get here? Financial crises are runs. No run, no “crisis.” People just lose money as in the tech bust. (Let me quickly plug here Darrell Duffie’s “Failure Mechanics of Dealer Banks.” This wonderful article explains exactly how our financial crisis was a run in dealer banks.)

For nearly 100 years we have tried to stop runs with government guarantees -- deposit insurance, generous lender of last resort, and bailouts. That stops runs, but leads to huge moral hazard. Giving a banker a bailout guarantee is like giving a teenager keys to the car and a case of whisky. So, we appoint regulators who are supposed to stop the banks from taking risks, in a hopeless arms race against smart MBAs, lawyers and lobbyists who try to get around the regulation, and though we allow – nay, we encourage and subsidize –expansion of run-prone assets.

In Dodd-Frank, the US simply doubled down our bets on this regime. The colossal failure of Europe’s regulators to deal with something so simple and transparent as looming sovereign risk hints how well it will work. (European banks have all along been allowed to hold sovereign debt at face value, with zero capital requirement. It’s perfectly safe, right?)

The guarantee – regulate - bailout regime ends eventually, when the needed bailouts exceed governments’ fiscal resources. That’s where Europe is now. And the US is not immune. Sooner or later markets will question the tens of trillions of our government’s guarantees, on top of already unsustainable deficits.

What financial system will we reconstruct from the ashes? The only possible answer seems to me, to go back to the beginning. We’ll have to reconstruct a financial system purged of run-prone assets, and the pretense that nobody holds risk. Don’t subsidize short-term debt with a tax shield and regulatory preference; tax it; or ban it for anything close to “too big to fail.” Fix the contractual flaws that make shadow-bank liabilities prone to runs.

Here we are in a golden moment, because technology can circumvent the standard objections. It is said that people need liquid assets, and banks must borrow short and lend long to provide such assets. But now, you could pay for coffee with an electronic transfer of mutual fund shares. The fund could hold stocks, or mortgage backed securities. Nobody ever ran on a (floating-NAV) mutual fund. With instant communication, liquidity need no longer coincide with fixed value and first-come first-serve guarantees. We also now have interest-paying reserves. The government can supply as many liquid assets as anyone wants with no inflation. We can live the Friedman rule.

Short-term debt is the key to government crises as well. Greece is not in trouble because it can’t borrow one year’s deficits. It’s in trouble because it can’t roll over existing debt. Governments can be financed by coupon-only bonds with no principal repayment, thereby eliminating rollover risk and crises. The new European treaty, along with wishing governments would mend their spending ways, should at least insist on long-maturity debt.

You may say this is radical. But the guarantee – regulate – bailout regime will soon be gone. There really is no choice. The only reason to keep the old regime is to keep the subsidies and bailouts coming. Which of course is what the banks want.

On to the US: Why are we stagnating? I don’t know. I don’t think anyone knows, really. That’s why we’re here at this fascinating conference.

Nothing on the conventional macro policy agenda reflects a clue why we’re stagnating. Score policy by whether its implicit diagnosis of the problem makes any sense: The “jobs” bill. Even if there were a ghost of a chance of building new roads and schools in less than two years, do we have 9% unemployment because we stopped spending on roads & schools? No. Do we have 9% unemployment because we fired lots of state workers? No.

Taxing the rich is the new hot idea. But do we have 9% unemployment – of anything but tax lawyers and lobbyists -- because the capital gains rate is too low? Besides, in this room we know that total marginal rates matter, not just average Federal income taxes of Warren Buffet. Greg Mankiw figured his marginal tax rate at 93% including Federal, state, local, and estate taxes. And even he forgot about sales, excise, and corporate taxes. Is 93% too low, and the cause of unemployment?

The Fed is debating QE3. Or is it 5? And promising zero interest rates all the way to the third year of the Malia Obama administration. All to lower long rates 10 basis points through some segmented-market magic. But do we really have 9% unemployment because 3% mortgages with 3% inflation are strangling the economy from lack of credit? Or because the market is screaming for 3 year bonds, but Treasury issued at 10 years instead? Or because 1.5 trillion of excess reserves aren’t enough to mediate transactions?

I posed this question to a somewhat dovish Federal Reserve Bank president recently. He answered succinctly, “Aggregate demand is inadequate. We fill it. ” Really? That’s at least coherent. I read the same model as an undergraduate. But as a diagnosis, it seems an awfully simplistic uni-causal, uni-dimensional view of prosperity. Medieval doctors had four humors, not just one.

Of course in some sense we are still suffering the impact of the 2008 financial crisis. Reinhart and Rogoff are endlessly quoted that recessions following financial crises are longer. But why? That observation could just mean that policy responses to financial crises are particularly wrongheaded.

In sum, the patient is having a heart attack. The doctors are debating whether to give him a double espresso or a nip of brandy. And most likely, the espresso is decaf and the brandy watered.

So what if this really is not a “macro” problem? What if this is Lee Ohanian’s 1937 – not about money, short term interest rates, taxes, inadequately stimulating (!) deficits, but a disease of tax rates, social programs that pay people not to work, and a “war on business.” Perhaps this is the beginning of eurosclerosis. (See Bob Lucas’s brilliant Millman lecture for a chilling exposition of this view).

If so, the problem is heart disease. If so, macro tools cannot help. If so, the answer is “Get out of the way.”

People hate this answer. They want to know “what would you do?” What’s the bold new plan? What’s the big new idea? Where is the new Keynes? They want FDR, jutting his chin out, leading us from the fear of fear itself. Alas, the microeconomy is a garden, not an army. It grows with property rights, rule of law, simple and non-distorting taxes, transparent rules-based regulations, a functional education system; all of George’s “simple obvious steps,” not the Big Plan for the political campaign of a Great Leader.

You need to weed a garden, not just pour on the latest fertilizer. Our garden is full of weeds. Yes, it was full of weeds before, but at least we know that pulling the weeds helps.

Or maybe not. This conference, and our fellow economists, are chock full of brilliant new ideas both macro and micro. But how do we apply new ideas? Here I think we economists are often a bit arrogant. The step from “wow my last paper is cool” to “the government should spend a trillion dollars on my idea” seems to take about 15 minutes. 10 in Cambridge.

Compare the scientific evidence on fiscal stimulus to that on global warming . Even if you’re a skeptic, compared to global warming, our evidence for stimulus -- including coherent theory and decisive empirical work -- is on the level of “hey, it’s pretty hot outside.” And compared to mortgage modification plans, strange “unconventional” monetary policy, the latest creative fix-the-banks plan, and huge labor market interventions, even stimulus is well-documented.

There are new ideas and great new ideas. But there are also bad new ideas, lots of warmed over bad old ideas, and good ideas that happen to be wrong. We don’t know which is which. If we apply anything like the standards we would demand of anyone else’s trillion-dollar government policy to our new ideas, the result for policy, now, must again be, stick with what works and the stuff we know is broken and get out of the way.

But keep working on those new ideas!