March 21, 2019
By YiLi Chien and Yi Wen
We build a tractable infinite-horizon Aiyagari-type model with quasi-linear preferences to address a set of long-standing issues in the optimal Ramsey taxation literature. The tractability of our model enables us to analytically prove the existence of Ramsey steady states and establish several strong and novel results: (i) Depending on the government’s capacity to issue debts, there can exist different types of Ramsey steady state and their existence depends critically on model parameter values. (ii) The optimal capital tax is exclusively zero in a Ramsey steady state regardless of the modified golden rule and government debt limits. (iii) Along the transition path toward a Ramsey steady state, optimal capital tax depends positively on the elasticity of intertemporal substitution. (iv) When a Ramsey steady state (featuring a non-binding government debt limit) does not exist but is erroneously assumed to exist, the modified golden rule always “holds” and the implied “optimal” long-run capital tax is strictly positive, reminiscent of the result obtained by Aiyagari (1995). (v) Whether the modified golden rule holds depends critically on the government’s capacity to issue debts, but has no bearing on the planner’s long-run capital tax scheme. (vi) The optimal debt-to-GDP ratio in the absence of a binding debt limit, however, is determined by a positive wedge times the modified-golden-rule saving rate; the wedge is decreasing in the strength of the individual self-insurance position and approaches zero when the idiosyncratic risk vanishes or markets are complete. The key insight behind our results is the Ramsey planner’s ultimate concern for self-insurance. Since taxing capital in the steady state permanently hinders individuals’ self-insurance positions, the Ramsey planner prefers (i) issuing debt rather than imposing a steady-state capital tax to correct the capital-overaccumulation problem under precautionary saving motives, and (ii) taxing capital only in the short run regardless of its debt positions. Thus, in sharp contrast to Aiyagari’s argument, permanent capital taxation is not the optimal tool to achieve aggregate allocative efficiency despite overaccumulation of capital, and the modified golden rule can fail to hold in a Ramsey equilibrium whenever the government encounters a debt-limit.
The literature on optimal capital taxation seems endless with conclusions getting reversed frequently, like whether eggs are healthy or not. This is another, but important, contribution that maybe will get us closer to resolution.
March 18, 2019
By Stefan Hohberger, Romanos Priftis and Lukas Vogel
This paper compares the distributional effects of conventional monetary policy and quantitative easing (QE) within an estimated open-economy DSGE model of the euro area. The model includes two groups of households: (i) wealthier households, who own financial assets and can smooth consumption over time, and (ii) poorer households, who only receive labor and transfer income and live “hand to mouth.” We compare the impact of policy shocks on constructed measures of income and wealth inequality (net disposable income, net asset position, and relative per-capita income). Except for the short term, expansionary conventional policy and QE shocks tend to mitigate income and wealth inequality between the two population groups.
This is an interesting result that absolves central banks from the criticism that their unconventional policies exacerbate inequality. However, I am afraid that the heterogeneity in this model is much too simple to be convincing. Indeed, their are really two representative agents in here: one who saves and one who does not. inequality is much more granular than that, and multidimensional. But one has to start somewhere.
March 14, 2019
By Pawel Krolikowski
This paper disciplines a model with search over match quality using microeconomic evidence on worker mobility patterns and wage dynamics. In addition to capturing these individual data, the model provides an explanation for aggregate labor market patterns. Poor match quality among first jobs implies large fluctuations in unemployment due to a responsive job destruction margin. Endogenous job destruction generates a burst of layoffs at the onset of a recession and, together with on-the-job search, generates a negative comovement between unemployment and vacancies. A significant job ladder, consistent with the empirical wage dispersion, provides ample scope for the propagation of vacancies and unemployment.
This is a cool paper that shows interesting heterogeneity in a labor search model. It should be applied to understand how demographic change alters the labor market and its dynamics.
March 3, 2019
By Robert Calvert Jump and Paul Levine
This paper provides a bird’s eye view of the behavioural New Keynesian literature. We discuss three key empirical regularities in macroeconomic data which are not accounted for by the standard New Keynesian model, namely, excess kurtosis, stochastic volatility, and departures from rational expectations. We then present a simple behavioural New Keynesian model that accounts for these empirical regularities in a straightforward manner. We discuss elaborations and extensions of the basic model, and suggest areas for future research.
Nice paper that considers extensions to the standard assumptions of the three-equation New-Keynesian model. It would be nice to see a similar one for DSGE models.
February 6, 2019
By Roger Farmer and Pawel Zabczyk
We demonstrate that the Fiscal Theory of the Price Level (FTPL) cannot be used to determine the price level uniquely in the overlapping generations (OLG) model. We provide two examples of OLG models, one with three 3-period lives and one with 62-period lives. Both examples are calibrated to an income profile chosen to match the life-cycle earnings process in U.S. data estimated by Guvenen et al. (2015). In both examples, there exist multiple steady-state equilibria. Our findings challenge established views about what constitutes a good combination of fiscal and monetary policies. As long as the primary deficit or the primary surplus is not too large, the fiscal authority can conduct policies that are unresponsive to endogenous changes in the level of its outstanding debt. Monetary and fiscal policy can both be active at the same time.
This is intriguing and further opens the discussion about possibly multiple regimes in the economy, which has dramatic implications for the conduct of policy.
February 2, 2019
By Benjamin Hartung, Philip Jung and Moritz Kuhn
A key question in labor market research is how the unemployment insurance system affects unemployment rates and labor market dynamics. We revisit this old question studying the German Hartz reforms. On average, lower separation rates explain 76% of declining unemployment after the reform, a fact unexplained by existing research focusing on job finding rates. The reduction in separation rates is heterogeneous, with long-term employed, high-wage workers being most affected. We causally link our empirical findings to the reduction in long-term unemployment benefits using a heterogeneous-agent labor market search model. Absent the reform, unemployment rates would be 50% higher today
I am really puzzled by the paper. Usually, when you have an economy with high unemployment rate, the job finding rate and the separation rate are both really low. A labor market reform then typically involves allowing the separation rate to increase, and then the job finding rate increases as well. But here, the separation rate decreased even further, with little consequence for the job finding rate. In other words, the labor market became even less flexible, yet the unemployment rate decreased substantially.
February 1, 2019
By Boris Chafwehé, Rigas Oikonomou, Romanos Priftis and Lukas Vogel
We propose a novel framework where forward guidance (FG) is endogenously determined. Our model assumes that a monetary authority solves an optimal policy problem under commitment at the zero-lower bound. FG derives from two sources: 1. from commiting to keep interest rates low at the exit of the liquidity trap, to stabilize inﬂation today. 2. From debt sustainability concerns, when the planner takes into account the consolidated budget constraint in optimization. Our model is tractable and admits an analytical solution for interest rates in which 1 and 2 show up as separate arguments that enter additively to the standard Taylor rule. In the case where optimal policy reﬂects debt sustainability concerns (satisﬁes the consolidated budget) monetary policy becomes subservient to ﬁscal policy, giving rise to more volatile inﬂation, output and interest rates. Liquidity trap (LT) episodes are longer, however, the impact of interest rate policy commitments on inﬂation and output are moderate. ’Keeping interest rates low’ for a long period, does not result in positive inﬂation rates during the LT, in contrast our model consistently predicts negative inﬂation at the onset of a LT episode. In contrast, in the absence of debt concerns, LT episodes are shorter, but the impact of commitments to keep interest rates low at the exit from the LT, on inﬂation and output is substantial. In this case monetary policy accomplishes to turn inﬂation positive at the onset of the episode, through promising higher inﬂation rates in future periods. We embed our theory into a DSGE model and estimate it with US data. Our ﬁndings suggest that FG during the Great Recession may have partly reﬂected debt sustainability concerns, but more likely policy reﬂected a strong commitment to stabilize inﬂation and the output gap. Our quantitative ﬁndings are thus broadly consistent with the view that the evolution of debt aggregates may have had an impact on monetary policy in the Great Recession, but this impact is likely to be small.
I do not think we yet a good theory of forward guidance, even less of forward guidance policy formation. This paper offers an interesting perspective in this respect. It may also offer an answer as to how forward guidance could have contributed to avoiding significant inflation despite the large increase in money supply.