Complexity in Monetary Policy: The Mechanisms Do Matter

Beware manufactured stability: "expectations management" is inherently fragile

A recent working paper adds to the discussion on monetary policy and growth.  In the model, monetary policy affects growth by allowing credit-intensive industries to engage in larger projects.  It does so by easing liquidity needs and, thus, giving firms the "breathing space" to invest.  The paper finds evidence for this by looking at industry-level financial constraint variables as well as the performance of the industry in response to monetary policy.  The key finding is that countercyclical monetary policy can have a significant positive impact on long run productivity growth, especially for recessions.  This result is robust to controlling for:

...the interaction between these measures of financial constraints and country-level economic variables such as inflation, financial development, and the size of government which are likely to affect the country’s ability to pursue more countercyclical macroeconomic policies (5).

Moreover, the regressions shed light on another unique internal link from monetary policy to growth: countercyclical monetary policy promotes higher levels of R+D spending.  While the model explains it through liquidity needs, the concept of "signal-processing" causing firms to invest inefficiently likely applies.  This suggests that if we really are in a "great stagnation" of growth and innovation, a stable nominal economy vis-a-vis monetary policy will be increasingly important.

To extend the model, if monetary policy exerts a diverse range of effects on what is considered money through safe asset creation, the effect of countercyclical monetary policy is probably stronger than what the interest rate would state.  By increasing liquidity through countercyclical policy, this allows firms to invest more:

The intuition for this proposition is simple. Firms need to hoard liquidity in order to weather liquidity shocks if the aggregate state is bad. This liquidity hoarding is costly...because of the lack of commitment of consumers. Reducing interest rates in bad times lowers the amount of hoarded liquidity, by increasing the ability of firms to leverage their net worth. This effect is weaker when the aggregate state is good because in that state, short-term profits are enough to cover reinvestment needs so that no liquidity needs to be hoarded to weather liquidity shocks that occur in that aggregate state of the world. Hence a higher marginal benefit of reducing interest rates in bad times relative to good times. This effect is strong enough to overcome a countervailing effect arising from the fact that lowering interest rates in bad times leads to an implicit subsidy from consumers to entrepreneurs, explaining that optimal interest rate policy is countercyclical (14, my emphasis).

And now the Nassim Nicholas Taleb homonculus starts screaming into my ear.

To what extent does this mechanism of monetary policy just create more interlocking fragilities?  I've previously argued that one of the problems with NGDP targeting is that it hides the complexity of the ecology of markets.  In this model, the world is encouraged to increase complexity because of a monetary regime that promotes more stable growth.  The firms with "unshakeable" expectations can leverage themselves to the hilt to try to maximize future growth.  But finance is fragile; what would happen if an unseen risk arises?  More seriously, although a debt crisis would wipe these firms out, nobody would be able to tell in the short run while those debt instruments are still there.

The issue here is that "average growth" is nowhere near as important as "variant growth".  While growth is stable most of the time, the impact of tail events rises as markets become more interconnected.  Leverage is inherently dangerous in an interconnected world because it enables complex cascading effects that go beyond the ability of our models to predict.  This uncertainty is heightened by the fact that even slight miscalibration errors can cause monstruous miscalculations.  These problems aren't solved by monetary policy either because financial crises are aggregate supply problems.  If credit mediation crashes, resources are no longer allocated efficiently, raising unit costs for all factors of production.

A possible way to get around this is if we can commit to more equity instead of leverage.  From Taleb's 10 principles for a Black-Swan free society:

5. Counter-balance complexity with simplicity. Complexity from globalisation and highly networked economic life needs to be countered by simplicity in financial products. The complex economy is already a form of leverage: the leverage of efficiency. Such systems survive thanks to slack and redundancy; adding debt produces wild and dangerous gyrations and leaves no room for error. Capitalism cannot avoid fads and bubbles: equity bubbles (as in 2000) have proved to be mild; debt bubbles are vicious.

This way, the net worth of companies can be converted into equity stakes, and funding can be obtained this way.  Given the outsize role of large events, this shift to a more black swan free society should occur before the adoption of monetary policies that could increase fragility.  In this world, monetary policy would allow for increased efficiency of markets while also preventing Black Swans from coming to roost.

Debt and Growth: The Chicken or the Egg?

..., and what to put in the European omelet?


How does debt affect growth?  The well-known correlation found by Rheinhart and Rogoff in their analyses of financial crises found that growth tends to substantially slow down as the debt to GDP ratio approaches 90%.  Based on this correlation, policy makers began to advocate austerity as a way to reduce debt, and thereby restore growth.

Of course, correlation does not prove causation, and Paul Krugman jumped at that, pointing out that it was quite likely that causation ran the other way.  As a result of anemic growth, countries would pursue countercyclical fiscal policy.  This would create the appearance that only low growth countries pursue higher levels of debt.  However, the association between the two variables actually arises from textbook countercyclical fiscal policy.  Had the government decided to retrench, the economy would have suffered even more, compounding the growth problem.

So how to resolve these issues?  A recent VoxEU article on the relationship between debt and growth caught my eye, as it proposed a novel mechanism to estimate the effect of debt on growth.  While I don't understand the full mechanics, the working paper seems to use the stock of foreign debt as a variable to instrument the stock of debt.  At the end of the analysis, the authors conclude that, while R+R find a strong correlation, the new data instrumented for endogenity cannot reject the null hypothesis that debt has no effect on growth.  This then has a critical role in determining policy because it suggests that countries, when in dire output straits, should not ignore the role of fiscal policy.  The debt effects are unlikely to be strong enough to overwhelm any first order effects from fiscal stimulus.  Especially given the recent interest in hysteresis and reductions in potential output, it seems almost certain that fiscal retrenchment is not the answer.  Along these lines, I also found some older articles, one an old study looking at old U.S. time series data, and another on Latin American growth, that both suggest we should be worry about the output gap.  Long run growth can be seriously affected by temporary deviations, and therefore we need to fill the gap, whether by fiscal or monetary policy.

Another note in the paper that was particularly interesting was that the authors traced much of the negative correlation between debt and growth to the destructive policies governments would pursue when at high levels of debt.  In the words of the authors:

We believe that there is a subtle channel through which high levels of public debt can have a negative effect on growth. In the presence of multiple equilibria, a fully solvent government with a high level of debt may decide to put in place restrictive fiscal policies aimed at reducing the probability that a change in investors’ sentiments would push the country towards the bad equilibrium. These policies, in turn, may reduce growth (Perotti 2012), especially if implemented during a recession (such policies may even be self-defeating and increase the debt-to-GDP ratio, DeLong and Summers 2012, UNCTAD 2011).3 In this case, it would be true that debt reduces growth, but only because high debt leads to panic and contractionary policies.

This argument piqued my interest for two key reasons.  The first is that it echoes a paper by Bernanke on the effect of supply shocks on the economy.  In the paper, Bernanke argued that a lot of the damage from a supply shock wasn't actually from the shock itself, but rather from the monetary policy response.  In the case of debt, much of the harm from high levels of debt isn't from the debt, but rather from the fiscal policy response.

The second is that this advice on debt and growth seems particularly pertinent for the Eurozone.  This paper provides strong evidence that the austerity cure is anything but.  Even if growth is needed, but fiscal retrenchment is not the answer.  Netherland's recent rejection of harsh cuts, and France's electoral shift both show that democracy is having its say and is refusing this cup of self-defeating suffering.  They recognize that cutting budgets cannot be the only way forward, and that policy needs to be fundamentally changed to recognize the elaborate chicken and egg relationship between debt and fiscal policy.  I only hope that they figure out that omelet before the bond markets take away the chance.