Owner-Occupied Housing and Wealth Inequality

On VoxEU, Gianni La Cava summarizes his research on the secular rise in the housing share of US income.

In the US national accounts, income accruing to the housing sector is measured as ‘net housing capital income’, or simply, net rental income (i.e. gross rents less housing costs, such as depreciation and property taxes). This measure includes rental income going to both owner-occupiers (imputed rent) and landlords (market rent). The very detailed nature of the Bureau of Economic Analysis’ regional economic accounts allows for similar estimates of housing capital income to be constructed for each US state spanning several decades. …

The owner-occupier share of aggregate income has risen from just under 2% in 1950 to close to 5% in 2014 … . The share of income going to landlords (i.e. market rent) has also doubled in the post-war era. But, in aggregate, the effect of imputed rent is larger … because there are nearly twice as many home owners as renters in the US economy. …

… the long-run rise in the housing capital income share is fully concentrated in states that face housing supply constraints.

Pawn Shops, Information Insensitivity, and Debt-on-Debt

In a BIS working paper (January 2015), Bengt Holmstrom summarizes some of the implications of the research on information insensitive debt. He cautions against moves to increase transparency in debt markets and defends the shadow banking system. He explains why opacity and information insensitivity are valuable and argues that debt-on-debt arrangements are (privately) optimal.

It all started with pawn shops:

The beauty lies in the fact that collateralised lending obviates the need to discover the exact price of the collateral. …

Today’s repo markets … are close cousins of pawn brokering with similar risks for the parties involved. … the buyer of the asset (the lender) bears the risk that the seller (the borrower) will not have the money to repurchase the asset and just like the pawnbroker, has to sell the asset in the market instead. The seller bears the risk that the buyer of the asset may have rehypothecated (reused) the posted collateral and cannot deliver it back on the termination date. … the risk that a pawnbroker may sell or lose the pawn was a big issue in ancient times and could explain why the Chinese pawnbrokers were Buddhist monks. …

People often assume that liquidity requires transparency, but this is a misunderstanding. What is required for liquidity is symmetric information about the payoff of the security that is being traded so that adverse selection does not impair the market. …

… stock markets are in almost all respects different from money markets …: risk-sharing versus liquidity provision, price discovery versus no price discovery, information-sensitive versus insensitive, transparent versus opaque, large versus small investments in information, anonymous versus bilateral, small unit trades versus large unit trades. … money markets operate under much greater urgency than stock markets. There is generally very little to lose if one stays out of the stock market for a day or longer. This is one reason the volume of trade is very volatile in stock markets. In money markets the volume of trade is very stable, because it could be disastrous if, for instance, overnight debt would not be rolled over each day. …

… debt-on-debt is optimal … . It is optimal to buy debt as collateral to insure against liquidity shocks tomorrow and it is optimal to issue debt against that collateral tomorrow. In fact, repeating the process over time is optimal, too, so debt is in a very robust sense the best possible collateral. This provides a strong reason for using debt as collateral in the shadow banking system. …

Panics always involve debt. Panics happen when information insensitive debt (or banks) turns into information-sensitive debt.

“Central Banking and Bitcoin: Not yet a Threat,” VoxEU, 2016

VoxEU, October 19, 2016. HTML.

  • Central banks are increasingly interested in employing blockchain technologies.
  • The blockchain threatens the intermediation business.
  • Central banks encounter the blockchain in the form of new krypto currencies, and as the technology underlying new clearing and settlement systems.
  • Krypto currencies bear the risk of “dollarization,” but in the major currency areas this risk is still small.
  • New clearing and settlement systems benefit from central bank participation. But central banks benefit as well; those rejecting the new technology risk undermining the attractiveness of the home currency.
  • See the original blogpost.

“Causes of the Transformation of the US Fiscal System in the 1930s,” VoxEU, 2016

VoxEU, October 11, 2016, with Martin Gonzalez-Eiras. HTML.

  • The US fiscal system underwent a radical transformation around the time of the Great Depression.
  • Perceived cost differences of revenue collection across levels of government, due to general equilibrium effects, can partly explain the rise of tax centralization and intergovernmental grants.
  • We develop a micro-founded general equilibrium model that blends politics and macroeconomics. (See the working paper.)

Nobel Laureates? École Normale Supérieure

In Nature, Tom Clynes reports about research indicating that École Normale Supérieure has the highest proportion of undergraduates that eventually win a Nobel prize. The California Institute of Technology comes second ahead of Harvard, Swarthmore, Cambridge, École Polytechnique, MIT, Columbia, Amherst, and Chicago.

Are We Real?

In the Guardian, Olivia Solon reports about the discussion on whether life as we experience it likely is a simulation.


… videogames are becoming more and more sophisticated and in the future we’ll be able to have simulations of conscious entities inside them. … If there are many more simulated minds than organic ones, then the chances of us being among the real minds starts to look more and more unlikely.

… That we might be in a simulation is … a simpler explanation for our existence …


… if we are in a simulation then we have no clue what the laws of physics are.


On Hygge and Gemütlichkeit

The Economist suggests that Danish Hygge (or German Gemütlichkeit) might go hand in hand with exclusion of strangers.

Denmark’s own natives may rank it top for happiness, but the immigrants in the survey [among expatriates] ranked it 60th in terms of friendliness, 64th for being made to feel welcome, and 67th for the ease of finding friends. … If cultures are obsessed with the joys of relaxing with old friends, perhaps it is because they find it stressful to make new ones.

Triple Coincidence in International Finance

On VoxEU, Stefan Avdjiev, Robert McCauley, and Hyun Song Shin discuss how a focus on net capital flows between countries can mislead policy analysts if they neglect heterogeneity between sectors in a country and/or non-congruence of economic and currency area that is, if they assume the “triple coincidence” between economic area, decision-making unit, and currency area.

The triple coincidence misleads

because it obscures gross flows, …

in that it gives insufficient weight to international funding currencies that are extensively borrowed outside the borders of their home countries …

if it glosses over the relevant decision-making unit by aggregating too much.

Puerto Rico and its Control Board

In the FT, Eric Platt offers an update on the debt situation in Puerto Rico:

  • The U.S. territory carries a USD 70 billion debt burden.
  • It has defaulted multiple times over the past year, “including on bonds backed with a constitutional guarantee.”
  • It did not have access to a court-backed restructuring process until Congress recently passed and President Obama signed the Puerto Rico Oversight, Management and Economic Stability Act (Promesa).
  • A seven-person control board controls the island’s finances and will oversee negotiations with creditors.
  • Puerto Rico has two weeks to submit a turnaround plan to the board.


15 years ago, Swissair stopped operating. Many of the fleet’s airplanes were grounded at Zurich airport. Staff and passengers could not understand the world, official Switzerland was in a state of shock, and public perceptions of UBS management which was considered to have acted in treacherous ways, started their long descend.

The movie: Grounding. Werner Enz looks back in the NZZ.


Cognitive Computing

On IBM Research Labs’ beautiful campus in Rüschlikon near Zurich, researchers are developing “cognitive computing” tools and applications, among others.

An IBM paper written in response to a White House request for information explains:

At IBM, we are guided by the term “augmented intelligence” rather than “artificial intelligence.” It is the critical difference between systems that enhance and scale human expertise rather than those that attempt to replicate all of human intelligence. We focus on building practical AI applications that assist people with well-defined tasks, and in the process, expose a range of generalized AI services on a platform to support a wide range of new applications.

We call our particular approach to augmented intelligence “cognitive computing.” Cognitive computing is a comprehensive set of capabilities based on technologies such as machine learning, reasoning and decision technologies; language, speech and vision technologies; human interface technologies; distributed and high-performance computing; and new computing architectures and devices. When purposefully integrated, these capabilities are designed to solve a wide range of practical problems, boost productivity, and foster new discoveries across many industries. This is what we bring to market today in the form of IBM Watson.

Cognitive computing in the kitchen: IBM chef Watson.

Doubts about Empirical Research

The Economist reports about research by Paul Smaldino and Richard McElreath indicating that studies in psychology, neuroscience and medicine have low statistical power (the probability to correctly reject a null hypothesis). If, nevertheless, almost all published studies contain significant results (i.e., rejections of null hypotheses), then this is suspicious.

Furthermore, Smaldino and McElreath’s research suggests that

the process of replication, by which published results are tested anew, is incapable of correcting the situation no matter how rigorously it is pursued.

With the help of a model of competing research institutes, Smaldino and McElreath simulate how empirical scientific research  progresses. Labs that find more new results also tend to produce more false positives. More careful labs try to rule out false positives but publish less. More “successful” labs are allowed to replicate. As a consequence, less careful labs spread out. Replication—repetition of randomly selected findings—does not stop this process.

poor methods still won—albeit more slowly. This was true in even the most punitive version of the model, in which labs received a penalty 100 times the value of the original “pay-off” for a result that failed to replicate, and replication rates were high (half of all results were subject to replication efforts).

Smaldino and McElreath conclude that “top-performing laboratories will always be those who are able to cut corners”—even in a world with frequent replication. The Economist concludes that

[u]ltimately, therefore, the way to end the proliferation of bad science is not to nag people to behave better, or even to encourage replication, but for universities and funding agencies to stop rewarding researchers who publish copiously over those who publish fewer, but perhaps higher-quality papers.


At the recent Karl Brunner Centenary event, Ernst Baltensperger characterized Monetarism as a set of five convictions:

  • Money matters (as accepted in the neoclassical synthesis)
  • Rules are preferred over discretion (in contrast to the views of Modigliani, Samuelson or Klein), but some flexibility is accepted
  • Inflation and inflation expectations are key (in contrast to traditional Keynesian views)—adaptive expectation formation, parallels to Phelps
  • Money growth targeting is useful—Brunner and Meltzer favored the monetary base, Friedman M1
  • Money, credit and the “details” of financial markets matter for the monetary transmission mechanism—Brunner and Meltzer pushed the credit view, parallels to Tobin

Baltensperger concluded that the macroeconomic mainstream has absorbed many of these convictions, as it has absorbed many pillars of Keynesian thought.

World War I Turned the Swiss Franc Into a Strong Currency

In Die Volkswirtschaft, Ernst Baltensperger and Peter Kugler summarize the history of the Swiss Franc since the mid 19th century:

  • After 1973, the Swiss Franc has been strong. Swiss Franc yields have been lower than what uncovered interest parity would suggest.
  • Before 1914, the Swiss Franc was weak in the sense that it enjoyed only limited credibility. In periods with fixed exchange rates, Swiss Franc yields typically exceeded yields in French Franc or Sterling.
  • Throughout the 20th century, the Swiss Franc appreciated by more than what inflation differentials would suggest, potentially reflecting the Balassa-Samuelson effect.

Pet Health Care

In an NBER working paper, Liran Einav, Amy Finkelstein, and Atul Gupta document similarities between healthcare for humans and pets in the US:

(i) rapid growth in spending as a share of GDP over the last two decades; (ii) strong income-spending gradient; (iii) rapid growth in the employment of healthcare providers; and (iv) similar propensity for high spending at the end of life.

The Trouble with Macroeconomics

The “Trouble with Macroeconomics,” according to a working paper by Paul Romer that is posted on his website, relates to dishonest identification assumptions, in particular in DSGE models used for policy analysis. Romer singles out calibration, assumptions about distribution functions and strong priors as culprits.

Romer argues that

[b]eing a Bayesian means that your software never barfs


I agree with the harsh judgment by Lucas and Sargent (1979) that the large Keynesian macro models of the day relied on identifying assumptions that were not credible. The situation now is worse. Macro models make assumptions that are no more credible and far more opaque.

Romer also offers a meta-model of himself as a critic of “post-real models” and “facts with unknown truth value.”

Karl Brunner

The SNB commemorated Karl Brunner’s 100th birthday with a Centenary Event and the first of a new lecture series, the Karl Brunner Distinguished Lecture Series. Allan Meltzer, Benjamin Friedman, Charlie Plosser, and Ernst Baltensperger reviewed Karl Brunner’s life and work at the event; Kenneth Rogoff delivered the lecture.

In the NZZ, Allan Meltzer writes about Karl Brunner. Ditto Kurt Schilknecht.


In the FAZ, Patrick Bernau und Manfred Schäfers report that the German Federal Ministry for Economic Affairs invited five research institutes to produce economic forecasts although the call for bids had stated that the Ministry would contract with at most four institutions. Legal experts agree that this procedure is illegal.

The report suggests that the institution that just made it (DIW) is led by Marcel Fratzscher who is politically close to the Minister.

Secular Stagnation Skepticism

I was asked to play devil’s advocate in a debate about “secular stagnation.” Here we go:

Alvin Hansen, the “American Keynes” predicted the end of US growth in the late 1930s—just before the economy started to boom because of America’s entry into WWII. Soon, nobody talked about “secular stagnation” any more.

75 years later, Larry Summers has revived the argument. Many academics have reacted skeptically; at the 2015 ASSA meetings, Greg Mankiw predicted that nobody would talk about secular stagnation any more a year later. But he was wrong; at least in policy circles, people still discuss and worry about secular stagnation. As we do tonight.

In his 2014 article, Summers does not offer a definition of “secular stagnation,” in fact the article barely mentions the term. But Summers tries to offer a unifying perspective on pressing policy questions. The precise elements of this perspective change from one piece in the secular stagnation debate to the other.

Summers (2014) emphasizes a conflict between growth and financial stability: He argues that before the crisis, growth was built on shaky foundations that resulted in financial instability; and after the crisis, projections of potential output were revised downwards.

Summers frames this conflict in terms of shifts in the supply of savings on the one hand and investment demand on the other, which are reflected in lower real interest rates.

He identifies multiple factors underlying these shifts:

  • The legacy of excessive leverage
  • Lower population growth
  • Redistribution to households with a higher propensity to save
  • Cheaper capital goods
  • Lower after tax returns due to low inflation
  • Global demand for CB reserves
  • Later added: Lower productivity growth
  • Risk aversion which creates a wedge between lending and borrowing rates

All this, Summers argues, is aggravated by the fact that nominal interest rates are constrained by the ZLB, and that low rate policies induce risk seeking and Ponzi games—that is, new financial instability—by investors.

I am not convinced by the diagnosis. First, I feel uncomfortable with “secular” theories of “lack of aggregate demand.” I guess I believe in some variant of Says’ law; I agree that the massive surge of CB reserves is relevant in this context but even this cannot rationalize “secular” demand failure (presumably, the surge will stop and may even be reversed or prices will adjust).

Second, I disagree on population growth. We have two workhorse models in dynamic macroeconomics, the Ramsey growth model and the overlapping generations model. In the former, population growth does not affect the long-term real interest rate (R = gamma^sigma / beta). In the latter, population growth can have an effect by changing factor prices; but in this model the real interest rate is unrelated to the economy’s growth rate.

Third, productivity growth clearly is relevant. Gordon would support the view that the outlook is bleak on that front, others would disagree and predict the opposite. We will know only in a few decades.

Fourth, domestic factors cannot be the dominant explanation. With open financial markets, global factors shape savings and interest rates.

Fifth, real interest rates have trended downward for thirty years, including in decades when no one worried about “demand shortfalls.” (Nominal rates trended downward too, but that is easy to explain.) But it is true that historically, low real rates tend to coincide with low labor productivity growth. Over the last years, low real rates have gone hand in hand with a stock market boom; this suggests financial frictions or increased risk aversion.

There are competing narratives of what is going on. For example, Kenneth Rogoff argues that we are experiencing the usual deleveraging process of a debt supercycle; in Rogoff’s view, the secular stagnation hypothesis does not attribute sufficient importance to the financial crisis. Bob Hall has identified an interesting structural break: Since 2000, households and in particular, the teenagers and young adults in those households supply less labor (they play video games instead).

Summers discusses three policy strategies in his 2014 article:

  • Wait and see (he associates this with Japan)
  • Policies that lower nominal interest rates to stimulate demand; Summers mentions various risks associated with this strategy, related to bubbles, redistribution, or zombie banks
  • Fiscal and other stimulus policies: Fiscal austerity only if it strongly fosters confidence; regulatory and tax reform; export promotion, trade agreements, and beggar thy neighbor policies; and public investment

I am not convinced by the medicine either. In general, I miss a clear argument for why policy needs to respond. We might be very disappointed about slower future growth. But this does not imply that governments should intervene. The relevant questions are whether we identify market failures; whether governments can improve the outcome (or whether they introduce additional failures); and whether it’s worth it. And this must be asked against the background that some of the trends described before may reverse sooner than later. For example, aggregate savings propensities are likely to fall when baby boomers start to dis-save, and Chinese savings have started to ebb.

More specifically, the Japanese approach over the last decades strikes me as following the third, stimulus strategy favored by Summers rather than the first, wait and see strategy that he dislikes. So we should discount this argument. (In any case, Japan might be a bad example since its per capita growth is not that low.) I agree that I don’t see much scope on the monetary policy side. Monetary policy also has the problem that interest rate changes have income in addition to substitution effects, and that it has lost effectiveness, both fundamentally and in terms of public perceptions. I believe that our views on monetary policy transmission will dramatically change in the next ten years (think for example about the discussion on Neo-Fisherianism). The interesting thing about Summers’ third, stimulus strategy is that it is much less demand focused than conventional wisdom would have it (think of regulation and taxes and confidence to some extent as well).

Finally, the argument for public investment as the instrument of choice is much weaker than Summers suggests. One can think of a situation where private investment is held back for various reasons and as a consequence, interest rates are low and public investment is “cheap.” Nevertheless, the optimal policy response need not be to invest; it could be preferable to eliminate the friction on private investment. For example, with excessively tight borrowing constraints, tax cuts for private investors could be appropriate. If we believe that demographics is the problem then investment could be counter productive as well (dynamic inefficiency in the OLG context). And public investment as an instrument for stimulus is problematic for politico-economic reasons. Low interest rates do not imply that debt is “for free.” It indicates that the supply of risk-free savings is ample, for example because markets are very concerned about tail risks.


Lawrence H. Summers (2014), “U.S. Economic Prospects: Secular Stagnation, Hysteresis, and the Zero Lower Bound,” Business Economics 49(2), 65—73.


Young Men in the US Work Fewer Hours

More discussion about falling employment of young men in the US:

  • John Rust publicizes the facts in a speech: Unskilled young men spend more time playing video games and less time in the labor market. “In 2015, 22 percent of lower-skilled men aged 21–30 had not worked at all during the prior 12 months.” They live in the basement of their parents’ houses and are not married. (And on his 12-year old son: “If we didn’t ration video games, I am not sure he would ever eat. I am positive he wouldn’t shower.)
  • Jason Richwine argues that the trend is restricted to natives as opposed to immigrants.
  • A critical assessment on We the Pleeple.

One of the first to point to the phenomenon was Bob Hall, for example at the 2015 ASSA meetings in Boston.

Have Banks Become Less Risky?

In BPEA, Natasha Sarin and Larry Summers argue that bank stock has not:

… we find that financial market information provides little support for the view that major institutions are significantly safer than they were before the crisis and some support for the notion that risks have actually increased. …

… financial markets may have underestimated risk prior to the crisis … Yet we believe that the main reason for our findings is that regulatory measures that have increased safety have been offset by a dramatic decline in the franchise value of major financial institutions, caused at least in part by these new regulations.

This table is taken from their paper:


However, their finding need not be as bad as it sounds. After all, bank regulators intended to insulate taxpayers against bank failure and to render the financial system more shock proof, not bank equity.