Technology Choice and Patent Scope

本稿の目的は,特許範囲の変更が,企業の技術選択にどのような影響を与えるかを,Mills and Smith (1996)の論文を援用しつつ分析することである.2企業が,第一ステージで旧技術と新技術のどちらを採用するかを同時に選択,第二ステージでクールノー競争を行なうというモデルを構築した.その際,新技術がdrastic innovationであるかどうかを考慮した.本稿で得た主な結論は次の通りである.(1)特許の保護範囲の拡大は,drastic innovationの場合,R&D投資企業数を増加させることはあるが,減少させることはない.non-drastic innovationの場合,R&D投資企業数を増加させることも減少させることも起こりうる.(2)経済厚生を比較した場合,特許範囲の拡大が厚生水準を増加させることはない.(3)経済厚生の観点から見ると,特許範囲の狭さ広さに関わらず,費用低下と投資費用の水準如何では,投資企業数が過少になることも過剰になることもある.(4)特許範囲の拡大によって社会的に望ましい投資企業数を達成できる場合は極めて限定的である.The purpose of this paper is to investigate the effect of the expansion of patent scope on the technology choice in an extended Mills and Smith (1996)\u27s model where patent is introduced. In the first stage, each of two firms simultaneously chooses one of two types of technology (a new technology and an old one). In the second stage, each of them competes in Cournot fashion. We establish : (1) If the new technology is drastic (non-drastic) innovation, then the expansion of patent scope facilitates (does not facilitate) each firm\u27s R & D investment. (2) The expansion may bring about socially optimal (excessive) number of firms engaging in R & D investment under some (other) pair of the level of unit cost and that of R & D expenditures

Social Inefficiency of Entry under Imperfect Competition : A Consistent Explanation

We consistently explain the excess entry theorem from the standpoint of the difference between the social planner's objective and each firm's one under standard oligopoly model. We introduce industry cost function which is derived from fitting-in function, and establish as follows : (1) Under second-best regulation, the real objective discrepancy results in the social inefficiency of entry from the first-best viewpoint. (2) Under no intervention the fictitious objective discrepancy generates entry bias from the second-best viewpoint, and both discrepancies generate this bias from the first-best one

On the Uniqueness of the Welfare-maximizing Number of Firms Under Cournot Oligopoly

Under Cournot oligopoly with a homogeneous product, we present a sufficient condition that guarantees the uniqueness of the welfare-maximizing number of firms to attain the global maximum level of welfare by implementation of a piecemeal policy changing the number of firms gradually. We adopt Selten's (1973) 'fitting-in function' method, which relates an individual firm's output to an industry's output. When the number of firms is unique, then introducing a lump-sum profit tax (subsidy) can attain the optimal level of welfare. Indirect entry regulation is superior to direct entry regulation from the standpoint of welfare if each entrant engages in rent-seeking activities. Copyright Blackwell Publishing Ltd and the Board of Trustees of the Bulletin of Economic Research 2003.

Location choice, competition, and welfare in non-tradable service FDI

We investigate whether non-tradable service FDI is efficient from a welfare point of view. A fixed number of firms strategically decide which markets to locate in and then compete in quasi-Cournot fashion. Considering firm location in two symmetric markets, non-tradable service FDI may or may not be efficient for the source country, depending on the total number of firms, competition in markets and the curvature of the demand function. In contrast, non-tradable service FDI is always efficient for the host country and the overall economy. This implies that any policy that affects firm location between two symmetric markets will not be beneficial from a welfare viewpoint.Non-tradable service FDI Location choice Quasi-Cournot behavior