This paper quantifies the welfare gains from Social Security when individuals face uninsurable longevity risk. While past researchers have studied this basic question, we do so from a unique perspective. In contrast to traditional macroeconomic models that abstract from specific linkages between parents and children, in our model, children are born to specific parents whose longevity is uncertain. And because parental asset holdings evolve over the life of the parent, children face uninsurable bequest income risk in addition to their own longevity risk. We find that Social Security improves ex ante expected utility by 3.4% of lifetime consumption (for the second generation). Because our baseline analysis assumes full information and optimal hedging of longevity risk, we treat these welfare gains as a conservative estimate, and we show that the gains are significantly larger when individuals fail to hedge their longevity risk.

The previous conclusion that a uniform lump-sum estate tax could implicitly provide annuity income was reached by ignoring the inheritance that agents receive. However, when the agents leave a bequest, they should also receive an inheritance from their parents. Thus, we make the inheritance received—bequests left cycle complete and fully endogenous. Interestingly, the differential timing and sizes of inheritance then generate unequal wealth effects even with actuarially fair annuity markets. To restore the first best, the government has to adopt an estate tax regime that is no longer uniform. Thus, once bequest is fully endogenized, a uniform estate tax no longer bears the annuity role. Further, the differential timing in receiving inheritance creates an unequal wealth distribution, which is also nonstationary. The paper manifests the importance of accounting for and tracing the inheritance received by agents for any crucial policy recommendation.

We assess the long-run growth effects of automation in the overlapping generations framework. Although automation implies constant returns to capital and, thus, an AK production side of the economy, positive long-run growth does not emerge. The reason is that automation suppresses wage income, which is the only source of investment in the overlapping generations model. Our result stands in sharp contrast to the representative agent setting with automation, where sustained long-run growth is possible even without technological progress. Our analysis therefore provides a cautionary tale that the underlying modeling structure of saving/investment decisions matters for the derived economic impact of automation. In addition, we show that a robot tax has the potential to raise per capita output and welfare at the steady state. However, it cannot induce a takeoff toward positive long-run growth.

Dynamic spatial theory has been a fruitful approach to understanding economic phenomena involving time and space. However, several central questions still remain unresolved in this field. The identification of the social optimal allocation of economic activity across time and space is particularly problematic, not been ensured yet in economic growth. Developing a monotone method, we study the optimal solution of the spatial Ramsey model. Under fairly general assumptions, we prove the existence of unique social optimum. Considering a numerical implementation of our algorithm, we study the role played by capital mobility in the neoclassical growth environment. With capital irreversibility and economic openness, space allows for transitional dynamics. Moreover, in this context, capital mobility is beneficial as well in terms of social welfare and inequality. We also consider an application of our method to an extension of the spatial Ramsey model for optimal land-use planning.

This paper analyzes a regime-switching New Keynesian model to understand what happens to the aggregate economy when the nominal interest rate hits the zero lower bound (ZLB). Contrary to the literature, our model predicts that the aggregate demand curve is not always upward sloping when the ZLB binds. Instead, it depends on expectations. If the expected duration of the ZLB is short but consistent with expectations surveys, the AD curve can be downward sloping. In that case, the fiscal multiplier is moderate and supply-side reforms are expansionary. These results complement existing findings in the literature.

This paper examines the effect of a tariff on long-run growth and welfare in a two-country innovation-led growth model. We show that although raising the home country’s tariff reduces the growth and GDP of the foreign country, it will backfire by depressing R&D and growth of the home country. The Nash equilibrium tariffs can be positive, and they are larger when the government expenditure is more beneficial to private production and/or when the productivity of innovation is higher. The presence of positive Nash equilibrium tariffs provides a theoretical explanation for why countries have incentives to implement a tariff policy regardless of its negative effect on growth. Finally, the Nash equilibrium tariffs are higher than the globally optimal tariffs, that is, the levels that maximize the joint welfare of both countries.

We explore R&D subsidies in a hybrid growth model which may exhibit semi-endogenous growth or fully endogenous growth. We consider two types of subsidies on variety-expanding innovation and quality-improving innovation. R&D subsidies on quality-improving innovation only have effects in the fully endogenous-growth regime, in which more subsidies cause an earlier activation of quality-improving innovation and increase the transitional/steady-state growth rate. R&D subsidies on variety-expanding innovation have contrasting effects in the two regimes. In the semi-endogenous-growth regime, more subsidies on variety-expanding innovation increase transitional growth but have no effect on steady-state growth. In the fully endogenous-growth regime, more subsidies on variety-expanding innovation continue to increase short-run growth but delay the activation of quality-improving innovation and reduce long-run growth. Increasing subsidies on variety-expanding (quality-improving) innovation makes the semi-endogenous-growth (fully endogenous-growth) regime more likely to emerge. Finally, we calibrate the model and find that under reasonable parameter values, the fully endogenous-growth regime is more likely to emerge.

This paper shows that the ability of the credible wage bargaining model to match the observed unemployment volatility hinges on an unrealistic assumption about disagreement payoffs to the firm. Relaxing this assumption can lead to the substantial wage flexibility. As a consequence, the model is unable to capture the observed unemployment volatility.

This paper examines how population aging affects the output effect of a government spending shock by using a panel data of OECD countries. The government spending shock is identified as a forecast error of government spending, and its output effect is estimated by using the local projection method. We find that population aging affects the output effect of the government spending shock. While in non-aging economies, government spending shock increases output significantly in both short- and medium-terms, in aging economies, output responses are not statistically significant.

Fixed search costs, that is, costs that do not vary with search duration, can amplify the cyclical volatility of the labor market. To assess the size of fixed costs, we analyze the relation between search costs and search duration using German establishment data. An instrumental variable estimation shows no relation between search duration and search costs. We conclude that search costs are mainly fixed costs. Furthermore, we show that a search and matching model, calibrated for Germany with fixed costs close to 75%, can generate labor market volatility that is consistent with the data.