Koichi Futagami

Keeping One Step Ahead of the Joneses: Status, the Distribution of Wealth, and Long Run Growth

Assuming that the utility of each agent depends on its relative wealth position in the society, this chapter constructs an endogenous growth model. It is shown that even if the subjective discount rates differ across agents, there exists a unique balanced growth equilibrium in which each agent owns a positive share of the world wealth. It is also shown that if the agents are identical then an increase in savings incentives always raises the long run growth rate but if they are heterogeneous then an increase in savings incentives may lower the long run growth rate.

Population aging and economic growth

This paper investigates how population aging affects economic growth in a general equilibrium model of life cycle savings combined with endogenous growth. It shows that population aging is not necessarily a negative factor for growth. Introducing an old age pension system into the model, the paper also examines the effects of a policy of postponing the retirement age, and suggests that such a policy would slow growth.

Dynamic analysis of patent policy in an endogenous growth model

Abstract In this paper, we explore the dynamic properties of an endogenous growth model with finite patent length. We show that there exists a unique equilibrium growth path and that this path exhibits damped oscillations in contrast to the equilibrium path of an endogenous growth model with infinite patent length. We also examine the effects of patent policy on social welfare and show that infinite patent length does not maximize social welfare. Furthermore, we show that, in a growth model that does not exhibit scale effects, a finite patent length maximizes social welfare on the balanced growth path.

Debt Policy Rule, Productive Government Spending, And Multiple Growth Paths

This paper constructs an endogenous growth model with productive government spending. In this model, the government can finance its costs through income tax and government debt and has a target level of government debt relative to the size of the economy. We show that there are two steady states. One is associated with high growth and the other with low growth. It is also shown that whether the government uses income taxes or government bonds makes the results differ significantly. In particular, an increase in government bonds reduces the growth rate in the high-growth steady state and raises the growth rate in the low-growth steady state. Conversely, an increase in the income tax rate reduces the growth rate in the low-growth steady state and there exists some tax rate that maximizes the growth rate in the high-growth steady state. Finally, the level of welfare in the low-growth steady state is lower than that in the high-growth steady state.

Growth Effects of Bubbles in an Endogenous Growth Model

This paper examines the possibility of the existence of bubbles and their effects on the growth rate by using an endogenous growth model. A necessary and sufficient condition for the existence of steady-state equilibrium with bubbles is provided. If non-zero rates of the useless asset supply are allowed, a steady-state equilibrium with bubbles exists even if the growth rate of the bubbleless equilibrium is lower than the market interest rate. The growth rate in the steady state with bubbles depends positively on the supply rate of the useless asset. Dynamic properties of bubbles are also analysed.

The Quality Ladder and Product Variety: Larger Economies May Not Grow Faster

This paper constructs an endogenous growth model that combines the quality ladder model and the variety expansion model. Firms enter an imitation race. After the imitation process, monopolistic competition prevails and a new innovation race begins. A successful firm, by inventing a higher quality product, can take over the entire market. However, the existence of a variety of products limits the price that the successful firm can charge. We show that the present model exhibits an inverted U-shape relationship between market size and growth rate. Relatively large and small economies grow slowly while medium-sized economies grow rapidly.

Demographic transition pattern in a small country

Abstract We investigate how the population growth rate changes along the transition path when the mortality rate decreases. It is shown that the existence of an altruistic household and child rearing costs is one of the factors which can explain the stylized fact called the ‘demographic transition pattern.’

Dynamic analysis of reductions in public debt in an endogenous growth model with public capital

We construct an endogenous growth model that includes productive public capital and government debt. We assume that the government debt-to-GDP ratio is gradually adjusted to a target level, reflecting the permanent commitment rules in the Stability and Growth Pact or the Maastricht Treaty in the European Union (i.e., the well-known 60% rule). These rules affect government borrowing and public investment. Here, we examine the welfare implications of the permanent commitment rules. We find that fiscal consolidation based on the rules improves social welfare. Moreover, the improvement in welfare accelerates as fiscal consolidation progresses more rapidly. Last, we also discuss and derive the optimal long-run debt-to-GDP ratio.

A Non-Unitary Discount Rate Model

The standard economic model of intertemporal decision making assumes that a single discount rate applies equally to discount (dis)utility from all different sources. However, studies such as psychology and behavioral economics have provided evidence that people might discount (dis)utility from different sources at different rates. This paper develops a simple model where the agent discounts utility from consumption at a different rate from disutility of labor supply. We show that in our non-unitary discount rate model, the preferences of the agent are time-inconsistent. The source of the time inconsistency is the difference between relative impatience with consumption and labor supply. It is shown that the policy effects in our model are quite different from those in the standard model. For example, when the agent discounts utility from consumption at a higher rate than the disutility of labor supply, the Friedman rule (the zero nominal interest rate) is no longer optimal. We also make comparisons between our results and those obtained in a model with a time variable discount rate where the preferences are time-inconsistent. It is also shown that the policy effects in our model are quite different from those in a model with a time variable discount rate.

Debt Policy and Economic Growth in a Small Open Economy Model with Productive Government Spending

In this paper, we examine the effects of introducing constraints on government borrowing using a continuous-time overlapping generations model of a small open economy. We consider government placing constraints on the amount of government bonds outstanding by establishing an upper limit, or target level, for the ratio of government bonds to gross domestic product. We first show that there exist multiple steady states in the model small open economy. One is a steady state with high growth, the other a steady state with low growth. We next examine how changes in the target level for bonds affect economic growth rates at the steady states. If the economy has a positive amount of asset holdings, we obtain the following results. When the government runs budget surpluses, an increase in the target level for government bonds reduces the growth rate of the low-growth economy, but raises the growth rate of the high-growth economy. However, when the government runs budget deficits, an increase in the target level for government bonds raises the growth rate of the low-growth economy, but reduces the growth rate of the high-growth economy. If the economy has a negative amount of asset holdings, the results are ambiguous.