Noisy selection model and the evolution of firm size and within-firm earnings distributions: a unified approach

Striking parallels observed in the evolution of firm size and within-firm earnings distributions over time are documented. At the time of entry, the distribution of the whole sample and that of eventual survivors look similar, but the distribution of survivors subsequently shifts to the right. The left tails thins out while the right tail thickens, and the variance increases. While separate theories in industrial organization and labor literature are offered to account for this evidence, we demonstrate that it can be explained in a unified framework presented by noisy selection. In particular, we show explicitly that noisy selection implies the shift of the conditional distribution to the right because less efficient workers (firms) face higher hazard rates before their true efficiency is revealed with certainty.     

Technology Choice,Overtaking, and Comparative Advantage*

This paper argues that the basic concept of comparative advantage, used in international trade theory to establish choices of commodities exported, can also be used to explain choice of technology by a firm. A firm with a current leading position in a given technology may spurn a new technology, which is developed by a currently lagging firm, leading to future overtaking.     

A theory of competitive industry dynamics with innovation and imitation

Empirical evidence on industry life-cycle reveals a pattern in which innovation rates remain fairly stable or are perhaps even higher at early stages, while patenting increases sharply as the industry matures. This increase in patenting in later stages is accompanied by net exit and lower rates of output growth and price decline. In this paper, we develop a dynamic model of a competitive industry with innovation and imitation that is consistent with these stylized facts. We derive an equilibrium growth path, along which leading firms invest in increasing the stock of technological knowledge and choose not to prevent imitation by other firms as long as the industry remains relatively small. As the industry expands including new entry, the leaders' optimal amount of investment gradually declines. We show that under some rather general conditions, there would exist a scale of the industry where innovating firms would choose to start preventing free imitation, bringing further expansion of the industry through new entry to a halt and causing net exit.     

Monopolistic Competition, Increasing Returns and International Coordination of Entry Policy

This paper presents a new model of monopolistic competition in which firms produce differentiated products under decreasing costs. This model is used to confirm and illustrate the limitations of the excess entry hypothesis, well known in the literature on industrial organization. The validity of the theorem is limited in the sense that it fails to hold in the present model if the properly defined degree of love for variety is sufficiently large. The model is extended to allow for intraindustry trade and to examine the conditions for gains (or losses) from trade in a two-country framework. It is shown how the degree of love for variety affects them. The significance and nature of international coordination of competition policy in the present setting is considered. The degree of love for variety is again shown to be of crucial importance in the characterization of the optimal policy coordination.     

The effects of Bank of Japan’s liquidity provision on the year-end premium

The premium on interbank money market rates arises over year-end periods as a result of the Japanese business practice of periodic settlement. This paper examines to what extent the Bank of Japan’s liquidity provision reduced the year-end premium in Japan. We find that the funds-supplying operations over the year-end and the fiscal year-end of 2008 had the largest effects during the period from 2006 to 2008, reflecting the fact that the Bank of Japan significantly expanded liquidity provision in response to the decrease in market liquidity under the financial turmoil.     

Regime uncertainty and optimal investment timing

We construct a real options model in which a regime change is expected at a pre-determined future time and study the effects of regime uncertainty on a firm's strategic investment decision, taking into consideration the remaining time to the regime change and the probability of each regime state. We show that just before the time of a regime change, firms should act as if the worst-case scenario was about to happen, even if a good state is highly possible.     

Market, Trade and Welfare in General Equilibrium

This paper develops a tractable general equilibrium model of an economy with an arbitrary number of industries under increasing returns to scale and imperfect competition. The market structure of the model economy is expressed by two basic sets of parameters: the degree of competition, and the markup ratio prevailing in each industry. The government is supposed to control the degree of competition through antitrust policy and the markup ratio through entry policy. Using this model, I re-examine the results of traditional competitive equilibrium analysis and explore the effects of competition policies on economic welfare and international trade.
JEL Classification Numbers: D43, D50, F11, F12, L13, L41.     

On the sharing of trade gains by resource-poor and resource-rich countries

A model of an asymmetric world composed of resource-poor and resource-rich countries. The scopes of ‘economic imperialism’ and ‘resource nationalism’ are then examined. It is shown that self-seeking resource-poor countries will completely exploit their resource-rich trading partners but that the latter will exploit the former only partially.