This paper studies the macroeconomic effects of seven key TCJA provisions, including the tax cuts for individuals and businesses, the bonus depreciation of equipment, the amortization of R&D expenses, and the limits on interest deductibility. I use a dynamic general equilibrium model with interest deductibility and accelerated depreciation. I find that, initially, the tax reform had a small positive effect on output and investment. In the medium term, however, the effect on output will diminish, and the effect on investment will turn negative. The tax reform will depress investment in R&D. Government debt will surge.

In practice, firms face a number of scarce innovation projects. They choose one towards which to direct their effort, but do not coordinate these choices. This gives rise to coordination frictions. This paper develops an expanding-variety endogenous growth model to study the implications of these frictions for growth and welfare. We find that the coordination failure generates a number of foregone innovations and reduces the economy-wide research intensity. Both effects decrease the growth rate. This creates a general equilibrium effect that endogenously amplifies the fraction of wasteful simultaneous innovation. Furthermore, formalizing the coordination frictions uncovers a novel link between the “stepping on toes” and “standing on shoulders” externalities—their magnitudes are endogenously determined through the ratio of firms to innovation projects. We find that the “stepping on toes” externality is larger for all parameter values.

We use a labor search model with heterogenous households and firms to study the efficacy of a wage subsidy during a pandemic, relative to enhancing unemployment benefits. A large proportion of the economy is forced to shut down, and firms in that sector choose whether to lay off workers or keep them on payroll. A wage subsidy encourages firms to keep workers on payroll, which speeds up labor market recovery after the pandemic ends. However, a wage subsidy can be costlier than enhancing unemployment benefits. If the shutdown is long or profit margins are low, then a wage subsidy is preferable and vice versa. The optimal mixture of policies includes a wage subsidy that covers 90$\%$ of the first $200/week of earnings and expands unemployment benefits to cover all salary up to $275/week. Low-income workers, as well as those in less productive jobs, benefit the most from a wage subsidy.

I develop a dynamic model of consumption variety in status goods by introducing a realistic aspect that is new in the existing literature—that a good will not carry status appeal unless it is advertised. As advertisements will divert resources from new product research, growth in new products will be reduced. However, status-good advertisements also enhance distinctiveness of a good and increase a firm’s profit. This will motivate more researches. With the two effects offsetting each other, the original market bias in a standard product-development model—insufficient research due to a general knowledge spillover—cannot be overcome. While introducing advertising into models of this kind does not reverse the original welfare implication of suboptimal growth, this makes available a new and better intervention option—taxing advertisements. This tax is superior to consumption tax, the conventional solution to inefficient status competition, as consumption tax is found to be ineffective in the present model. It is also superior to research subsidies, the conventional solution to suboptimal growth, as subsidies must be financed and is not a self-sufficient policy.

We estimate the elasticity of substitution between high-skill and low-skill workers using panel data from 32 countries during 1970–2015. Most existing estimates, which are based only on US microdata, find a value close to 1.6. We bring international data together with a theory-informed macro-approach to provide new evidence on this important macroeconomic parameter. Using the macro-approach, we find that the elasticity of substitution between tertiary-educated workers and those with lower education levels falls between 1.7 and 2.6, which is higher than previous estimates but within a plausible range. In some specifications, estimated elasticity is above the value required for strong skill-bias of technology, suggesting strong skill-bias is possible.

What determines the strength of the relationship between money growth and inflation? A large literature suggests that it has weakened since the 1980s, without a definitive explanation of the cause. I explore how population age structure explains changes in the pass through of money growth rates to inflation. I show that the quantity theory of money holds over long time horizons, with sizable estimates of the impact of money growth on inflation in the short to medium term. Various measures of population age structure have significant impact on the strength of this relationship. These demographics account for an increase in the transmission of money growth to prices in the 1970s and a weakening throughout the great moderation. The baby boomer cohort, now in the age groups around retirement, may exert upward pressure on this money transmission to prices at present, with ambiguous implications in the future as low fertility and rising longevity persist.

Using monthly headline inflation data covering 184 countries for the period between January 1971 and December 2020, this paper investigates the role of standard gravity variables on inflation convergence across country pairs. The convergence analysis by unit root tests is based on ten-year rolling windows to control for potential structural changes over time, whereas the corresponding results are connected to the standard gravity variables in the preceding year to investigate the drivers of inflation convergence and its speed. Regarding the existence of inflation convergence, empirical results show that having a common currency, a free trade agreement, proximity, a common border, or a colonial relationship between countries increases the probability of inflation convergence. Regarding the speed of inflation convergence, the very same gravity variables are shown to reduce the half-life of convergence. In both cases, the effects of having a common currency are shown to dominate those of other gravity variables.

This paper examines whether changes in US presidential administration and central bank turnover during the period 1976–2016 caused regime shifts in Taylor rule deviations. Using a dynamic stochastic general equilibrium model to construct the welfare-maximizing policy rule and deviations from the optimal rule, we find evidence that politics indeed play a key role in explaining these deviations. In addition to politics, unemployment rates and the interest rate spread significantly account for regime shifts in Taylor rule deviations.

In a canonical model of heterogeneous agents with precautionary saving motives, Aiyagari [(1995) Journal of Political Economy 103(6), 1158–1175.] breaks the classical result of zero capital tax obtained in representative-agent models. Aiyagari argues that with capital overaccumulation the optimal long-run capital tax should be strictly positive in order to achieve aggregate allocative efficiency suggested by the modified golden rule (MGR). In this paper, we find that, depending on the sources of capital overaccumulation, capital taxation may not be the most efficient means to restore the MGR when government debt is feasible. To demonstrate our point, we study optimal policy mix in achieving the socially optimal (MGR) level of aggregate capital stock in an infinite horizon heterogeneous-agents incomplete-markets economy where capital may be overaccumulated for two distinct reasons: (i) precautionary savings and (ii) production externalities. By solving the Ramsey problem analytically along the entire transitional path, we reveal that public debt and capital taxation play very distinct roles in dealing with the overaccumulation problem. The Ramsey planner opts neither to use a capital tax to correct the overaccumulation problem if it is caused solely by precautionary saving—regardless of the feasibility of public debt—nor to use debt (financed by consumption tax) to correct the overaccumulation problem if it is caused solely by production externality (such as pollution)—regardless of the feasibility of a capital tax. The key is that the MGR has two margins: an intratemporal margin pertaining to the marginal product of capital (MPK) and an intertemporal margin pertaining to the time discount rate. To achieve the MGR, the Ramsey planner needs to equate not only the private MPK with the social MPK but also the interest rate with the time discount rate—neither of which is equalized in a competitive equilibrium. Yet public debt and a capital tax are each effective only in calibrating one of the two margins, respectively, but not both.

We revisit the Friedman rule in a labor search model and extend Heer (2003), Cooley and Quadrini (2004), and Wang and Xie (2013) to one that allows for endogenous growth. We show that, even without a liquidity effect or a CIA constraint on firms’ wage payment, our model offers a different channel for moderate money growth to increase welfare. Intuitively, in a one-sector endogenous growth economy, the technology is of constant returns with respect to capital. When the labor market is frictional, a moderate increase in money growth induces an expansion in vacancy and employment. Labor and capital are complements in production. With an increase in employment, when the technology is neoclassical, the decreasing return in capital leads to a lower marginal product of labor. However, in an endogenous growth framework wherein the technology exhibits socially constant returns in capital, the marginal product of labor is constant. Due to a constant marginal product of labor, modest inflation raises employment, enlarges economic growth, and increases welfare. Moreover, the optimal long-run inflation rate departs from the Friedman rule, even when the Hosios rule holds. Finally, we find that our model with sustainable growth fits the data better than that without sustainable growth.