Health insurance reform and economic growth: Simulation analysis in Japan

This paper evaluates the drastic reforms of Japanese public health insurance initiated in 2006. We employ a computable general equilibrium framework to numerically examine the reforms for an aging Japan in the dynamic context of overlapping generations. Our simulation produced the following results: first, an increase in the co-payment rate, a prominent feature of the 2006 reform, would promote economic growth and welfare by encouraging private saving. Second, the ex-post moral hazard behavior following the increase in co-payment rates, however, reduces economic growth. Third, Japan's trend of increasing the future public health insurance benefits can mainly be explained by its aging population, and increasing the co-payment rate does little to reduce future payments of public health insurance benefits. Fourth, the effect on future economic burdens of reducing medical costs through efficiencies in public health insurance, emphasis on preventive medical care, or technological progress in the medical field is small. Finally, a policy of maintaining public health insurance at a fixed percentage of GDP will require reducing public health insurance benefits, perhaps up to 45% by 2050. Such a policy also reduces economic growth until approximately 2035. Our simulation indicates that the reform does not significantly reduce future public health insurance benefits, but it can enhance economic growth and welfare by encouraging private saving.     

Endogenous Role in Mixed Markets: A Two-Production-Period Model

In this paper, I investigate endogenous roles in a mixed duopoly, where private and state-owned public turns compete, by allowing two production periods. I find that many equilibria exist, including the Coumot-type equilibrium and one Stackelberg-type equilibrium where the public firm becomes the follower. However, another Stackelberg-type equilibrium where the public firm becomes the leader does not exist. If small inventory costs are introduced, the unique equilibrium outcome becomes the Stackelberg type where the public firm is the follower.     

Consumer‐benefiting exclusive territories

Abstract.  I investigate the effect of exclusive territories, which are typical vertical controls imposed by upstream firms. Using shipping spatial models, I consider an industry that consists of many independent local markets. An upstream monopolist restricts competition between downstream firms using exclusive territories. I find that exclusive territories reduce the prices of final products in all local markets in quantity‐setting competition. In price‐setting competition, they raise prices in half the local markets, reduce them in other markets, and also reduce the total consumer surplus. JEL classification: L42, R32     

Corporate Social Responsibility or Payoff Asymmetry? A Study of an Endogenous Timing Game

We revisit an endogenous timing game by introducing corporate social responsibility into firms' payoffs. Previous research investigates an endogenous timing game in a mixed oligopoly, wherein one welfare‐maximizing public firm competes against profit‐maximizing private firms. It shows that the outcome is completely different from that of private oligopoly. In contrast to its result, we find that this change in payoff does not matter as long as the payoffs are symmetric. Our result indicates that asymmetry, and not welfare‐concerning objectives, yields specific results in the literature on mixed oligopoly.     

The spatial selection of heterogeneous firms

We show that heterogeneous firms choose different locations in response to market integration. Specifically, decreasing trade costs lead to the gradual agglomeration of efficient firms in the larger country where they have access to a bigger pool of consumers. In contrast, high-cost firms seek protection against competition from efficient firms by locating in the smaller country. However, when the spatial separation of markets ceases to be a sufficient protection against foreign competition, high-cost firms choose to set up in the larger market. Hence, the relationship between economic integration and international productivity gap first increases and then decreases with market integration.     

Endogenous Timing in Mixed Duopolies With Externality

We investigate endogenous timing in a mixed duopoly with a negative externality. We find that quantity (price) competition yields a simultaneous‐move (sequential‐move) outcome under a significant negative externality. These results indicate that mixed duopolies yield the same results as private duopolies under a significant negative externality, which is in sharp contrast to the results in mixed duopolies without a negative externality. Unless the negative externality is insignificant, public leadership yields greater welfare than private leadership, and public leadership is more robust than the private leadership as equilibrium. If optimal environmental tax policy is introduced, however, private leadership yields the greatest welfare and this an equilibrium outcome in the endogenous timing game under quantity competition.     

The dynamics of open-market operations and the assignment problem

The purpose of this paper is to examine the implications of expansionary monetary policy financed by open-market purchases and to reconsider the assignment problem. We present a strict definition of open-market operations: a swap of money against bonds is achieved by just buying or selling bonds in the open market all through the adjustment process. Under this definition the open-market paradox given by Blinder and Solow is avoided. Even in the case of zero capital mobility, the assignment problem has an important economic meaning.     

Firm heterogeneity and Ricardian comparative advantage within and across sectors

This paper incorporates Melitz’s Econometrica (71:1695–1725, 2003) heterogeneous-firm trade model in the Ricardian model of comparative advantage with a continuum of sectors introduced by Dornbusch et al. (Am Econ Rev 67(5), 823–839, 1977). In particular, we characterise the equilibrium outcomes when neither sectors nor countries are symmetric. We find that trade patterns can follow Ricardian comparative advantage, while wage rates are proportional to market size due to a home market effect. Interestingly, trade liberalisation hurts the large country but benefits the small one by reducing the number of sectors with two-way trade and expanding those with specialised (one-way) trade. I would like to thank Mike Artis, Richard Baldwin, Frederic Robert-Nicoud, Matthias Helble, Giovanni Facchini, Thierry Verdier and a referee for their helpful comments and suggestions. Also I would like to thank Mike Artis for his excellent proof reading.