Dynamic analysis of patent policy in an endogenous growth model

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.     

Patent term extensions and commercialization lags in the pharmaceutical industry: A growth-theoretic analysis

Due to the lags in commercialization, the effective life of a patent is generally less than its statutory term. We introduce commercialization lags into the Schumpeterian growth model and explore the effects of patent term extensions on pharmaceutical R&D and social welfare. Our results show that extending patent terms stimulates the consumption of homogeneous goods but generates an ambiguous effect on the consumption of pharmaceuticals. When patent extensions have an inverted-U effect on social welfare, the optimal patent extension increases with the length of commercialization lags but decreases with the input intensity of commercialization lags. Finally, we calibrate the model and find that increasing patent breadth reduces the optimal patent extension.     

Human capital use,innovation, patent protection,and economic growth in multiple regions

We provide the first theoretical analysis of the effects of human capital use, innovative activity, and patent protection, on economic growth in a model with many regions. In each region, consumers have constant relative risk-aversion preferences, there is no human capital growth, and there are three kinds of manufacturing activities involving the production of blueprints for inputs (machines), the inputs themselves, and a single final consumption good. Our analysis generates four results. For any given region, we first describe the balanced growth path (BGP) equilibrium and show that the BGP growth rate depends negatively on the rate at which patents expire. Second, we characterize the transitional dynamics in our model. Third, we determine the value of the patent expiry rate that maximizes the equilibrium growth rate of a region. Finally, we show that a policy of offering perpetual patent protection does not necessarily maximize social welfare in a region.     

Commodity Taxation and the Effects of Entry: A Case of Variety Preferences

We study the relationship between commodity taxation and the effect of entry with imperfect competition. We develop a simple general equilibrium model with imperfect competition in which consumers have variety preferences. As a result, we see that introducing specific taxes increases social welfare. Furthermore, we show that the optimal tax rule is contrary to the inverse elasticity rule.Acknowledgement We wish to thank two anonymous referees for their helpful comments.     

Effects of a blocking patent on R&D with endogenous survival activities

This study analyzes the effect of strengthening patent protection for innovation and economic growth by introducing a blocking patent into the endogenous growth model developed by Furukawa (Econ Lett 121(1):26–29, 2013a), which features survival activity of patent holders in the R&D sector with a variety-expansion model. Results show that strengthening patent protection can raise the economic growth rate and social welfare through an endogenous survival investment. Additionally, this study examines the effects of increasing subsidies for R&D. We find that increasing R&D subsidy rate can negatively affect economic growth and social welfare because of the investment for survival activities. This result shows the novel role of a blocking patent in determining innovation effects of R&D subsidies. Furthermore, we analyze the effect of patent breadth which is another patent instrument in this model on innovation and economic growth. Results show that the growth and welfare effects of the profit-division rule and the subsidy rate for R&D may vary with the size of patent breadth.     

Competitive equilibrium hyperinflation under rational expectations

This paper shows that a competitive equilibrium model, where a representative agent maximizes welfare, expectations are rational and markets are in equilibrium can account for several hyperinflation stylized facts. The theory is built by combining two hypotheses, namely, a fiscal crisis that requires printing money to finance an increasing public deficit and a predicted change in an unsustainable fiscal regime.We thank an anonymous referee for very helpful comments. A. B. Cunha acknowledges financial support from the Brazilian Council of Science and Technology (CNPq).     

Money and insurance in a turnpike environment

Summary We study the effects of introducing a feasible insurance market into the spatial separation model of money described in Mitsui and Watanabe (1989). We show that the insurance contract may or may not drive out money. We also show that, depending on the degree of risk aversion, the additional market can reduce welfare for all agents, increase welfare for all agents, or increase welfare for some agents and reduce it for others.The authors would like to thank Ed Green, Preston Miller, Ed Prescott and Neil Wallace for valuable comments.     

Theory and practice of monetary policy

Summary. We consider an optimally managed renewable resource with stochastic non-concave growth function. We characterize the conditions under which the optimal policy leads to global extinction, global conservation and the existence of a safe standard of conservation. Our conditions are specified in terms of the economic and ecological primitives of the model: the biological growth function, the welfare function, the distribution of shocks and the discount rate. Our results indicate that, unlike deterministic models, extinction and conservation in stochastic models are not determined by a simple comparison of the growth rate and the discount rate; the welfare function plays an important role.Received: 20 October 2004, Revised: 28 February 2005, JEL Classification Numbers: D90, O11, O41, Q32.Santanu Roy: Correspondence toResearch on this paper was completed when the second author visited Cornell University in July, 2003. We thank the Center for Analytic Economics and the Department of Economics at Cornell University for making this research visit possible. The current version has gained considerably from the comments made by an anonymous referee.     

Effect of credible quality investment with Bertrand and Cournot competition

We show how credible revelation and ability to commit to quality choice effect equilibrium qualities and welfare when product market is either Bertrand or Cournot competition. We show that results depend on the type of competition but not generally on the cost of quality function. We show that with Bertrand competition, the equilibrium qualities are lower with credible commitment. Competition is moderated and producer surplus is higher and consumer surplus lower. With Cournot competition, higher quality will be better but lower quality will be worse with credible commitment. Consumer surplus is always greater with credible commitment and if cost does not increase too quickly with quality, producer surplus will also increase. Thus credible commitment is a collusive device with Bertrand competition but it can improve social welfare with Cournot competition. Received: February 8, 2000; revised version: February 14, 2002 RID="*" ID="*" The idea of this paper originated in the weekly workshops of Mordecai Kurz at Stanford. I am forever in debted to Mordecai and fellow students – Luis Cabral, Peter DeMarzo, John Hillas, Michihiro Kandori, Steve Langois, Patrick McAllister, Steve Sharpe, Peter Streufert, Steve Turnbull and Gyu-Ho Wang – for their criticism and encouragement. I also benefited from comments from Yi-Heng Chen, Jin-Li Hu, Kala Krishna, Jinji Naoto, Thomas J. Prusa, and Shyh-Fang Ueng at various later stages of this work. Last but not least, I am grateful for the detailed comments of the referee.     

Patent claims and economic growth

This study introduces a blocking patent on horizontal R&D into the endogenous growth model of Chu et al. (2012), which features a blocking patent on vertical R&D. Results show that strengthening patent protection on horizontal R&D promotes vertical innovation (quality improvement) but hinders horizontal innovation (variety expansion). This effect of a horizontal blocking patent on directionality of innovation is opposite to that of the vertical blocking patent analyzed by Chu et al. (2012). Results also show that under mild conditions, strengthening a blocking patent on horizontal innovation as well as on vertical innovation can increase economic growth and social welfare.     

最优专利制度研究

本文构建了一个动态一般均衡模型来研究最优专利长度和最优专利宽度的问题。研究结论表明,最优的专利长度和专利宽度都是有限的。专利长度的增加会通过促进创新来提高社会福利水平,同时,也会导致市场扭曲,从而降低社会福利水平,但随着专利长度的不断增加,前者的效应会小于后者的效应,因此,有限的专利长度是最优的。有效的专利宽度应该一方面使得模仿产品的质量水平不要太低,从而保证模仿产品对专利产品形成潜在的威胁,逼迫专利产品的价格低于垄断价格,减小市场扭曲;另一方面使得模仿产品的质量不要太高,从而保证专利产品能够制定较高的垄断价格,促进创新。     

Environmental taxes and strategic delegation

This paper analyzes a managerial delegation model in which the government chooses an environmental tax to control environmental damage. By giving the managers of firms an incentive scheme based on a linear combination of profit and sales revenue, we show that firm owners have to pay a higher environmental tax and both environmental damage and social welfare increase compared to the profit-maximization case. Financial support from UPV (Subvención a grupos, 2001), UPV (HB-8238/2000) and MEC (BEC 2000-0301) is gratefully acknowledged. We would like to thank A. Saracho and two referees for helpful comments. The usual disclaimer applies.     

Does intellectual monopoly stimulate or stifle innovation?

This study develops an R&D-based growth model with vertical and horizontal innovation to shed some light on the current debate on whether patent protection stimulates or stifles innovation. We analyze the effects of patent protection in the form of blocking patents. We show that patent protection changes the direction of innovation by having asymmetric effects on vertical innovation (i.e., quality improvement) and horizontal innovation (i.e., variety expansion). Calibrating the model and simulating transition dynamics, we find that strengthening the effect of blocking patents stifles vertical innovation and decreases economic growth but increases social welfare due to an increase in horizontal innovation. In light of this finding, we argue that in order to properly analyze the growth and welfare implications of patents, it is important to consider their often neglected compositional effects on vertical and horizontal innovation.     

Tariff reforms with rigid wages

This paper analyses the effects of tariff reforms on welfare and market access in a competitive small open economy, which is characterised by involuntary unemployment due to non-market clearing wages that are fixed either in terms of the numeraire or in real terms. We show that recent tariff-reform results can be extended to integrated reforms of tariffs and the wage rate, and that the inherent tension between reforms that increase welfare and market access carries over. We also derive welfare increasing tariff-reform strategies that keep the wage rate constant and show that this tension may be attenuated. We thank Peter Neary, an anonymous referee, as well as participants at the GEP Conference on New Directions in Trade Theory and at the ETSG Annual Conference in Athens for helpful comments. We acknowledge gratefully financial support from the Leverhulme Trust under Programme Grant F114/BF.     

PRODUCTIVE GOVERNMENT SPENDING,PATTERNS OF SPECIALIZATION AND ECONOMIC GROWTH IN A SMALL OPEN ECONOMY*

Constructing a two‐sector small open endogenous growth model with productive government spending, this paper examines patterns of specialization and the growth effects of fiscal policy. It is shown in this model that a change in income tax rate can cause a change in an equilibrium pattern of specialization. Because of this property, the relationship between the tax rate and the growth rate yields either a humped shape or a two‐humped shape, depending on world commodity prices. We also show that the growth maximizing tax rate is not necessarily equal to the tax rate that maximizes the level of social welfare.     

Fiscal counter-cyclical rules and their conflicting implications for growth and welfare

The paper examines the choices for fiscal stabilisation policy that maximise aggregate welfare and long-run growth. This is done in the context of a stochastic dynamic general equilibrium model where premeditated learning provides the engine of human capital accumulation and growth, and technology shocks provide the impulse source of fluctuations. Contrary to existing conventional wisdom, the results indicate a conflict between the two policy objectives: the choice of no stabilisation, associated with maximum growth, is also associated with minimum welfare. Welfare maximisation requires a full counter-cyclical response to the occurrence of business cycles. I am grateful to three anonymous referees for their constructive comments and suggestions. I would also like to thank Theodore Palivos, Keith Blackburn, seminar participants in Athens and Thessaloniki, and participants at the 2006 conference on Theories and Methods in Macroeconomics (Toulouse) and the 2007 conference of the Society for the Advancement of Economic Theory (Kos), for their valuables comments and suggestions on earlier drafts. Any errors and omissions are mine.     

Structure of distortion equilibria and welfare in a multiregional economy

Summary We consider a convex economy with multiregions, each region facing different specific tax-subsidies. The model reduces to a model of a closed economy with an aggregate production set when there is a single region. It can also represent a model of an international economy through a reinterpretation of variables. We show that there is a unique path of allocations from a distortion equilibrium to the optimum that can be followed by proportionate changes of price distortions. Welfare monotonically increases as one follows the path towards optimum. The information on the structure of equilibria reduces multidimensional comparative statics into a one dimensional problem. The global Newton method of Smale can be used to follow the path in the direction of increasing welfare, allowing us to do comparative statics computationally. Global considerations directly show that, under a sign condition of the Jacobian of a tax function, piecemeal proportional reductions of price distortions improve welfare. A variation of the condition unifies other such conditions in the literature.I would like to thank William Brock, Takashi Fukushima, Tatsuo Hatta, Michael Jerison, Taesung Kim and referees of this Journal who provided me with many constructive comments and references. Previous versions of this paper were presented at the Far Eastern Meeting of the Econometric Society, the Midwestern Mathematical Economics Conference, and the International Conference of Korean Economists. I wish to thank the participants of these conferences for many nice comments. I also wish to thank Bruce Dieffenbach, Thad Mirer and editors of this journal who helped to streamline exposition.     

Union-oligopoly bargaining and entry deterrence: a reassessment of limit pricing

This paper introduces wage bargaining in the framework of Milgrom and Roberts (Econometrica 50(2):443–459, 1982) where the workers’ reservation wage is the private information parameter critical for entry. We show that entry threat significantly distorts the wage, which in some cases adversely affects the firm’s ability to signal through price. Consequently, the separating equilibrium (in price) does not always exist. If, however, wage agreements are made public, signalling occurs with or without distortions in wage depending on whether the union’s bargaining power is high or low. Pooling equilibrium also exists and it features similar distortions. We also examine which signal, wage or price, generates greater social welfare. We would like to thank two referees for their helpful comments and suggestions. This paper is partially based on a chapter of Pal’s PhD thesis done at Indira Gandhi Institute of Development Research (IGIDR), India. For remaining errors we are solely responsible.     

Media Plurality: Private versus Mixed Duopolies

In this paper, we analyze the level of media plurality in a market with two private news firms (private duopoly) and in a market with a private news firm and a public news firm (mixed duopoly). In the private duopoly news firms maximize profits. In the mixed duopoly, the private news firm maximizes profits, while the public news firm maximizes social welfare. We show that, in spite of the public news firm maximizing social welfare, neither media plurality nor social welfare needs to be higher under the mixed duopoly compared with the private duopoly. This will depend on the relation between the costs of adapting news to readers' political preferences, the intensity of the readers' political preferences, and the size of the advertising market.     

Dynamic pollution regulation

This paper examines pollution regulation in a dynamic setting with complete information. We show that tradeable pollution permits may not achieve the social optimum even when the permit market is perfectly competitive. The reason is that the optimal tradeable permits regulation will typically be time inconsistent. We then show that pollution taxes can achieve the first best and are time consistent.We thank Claudio Mezzetti, Wally Oates, and Paul Rhode for helpful comments. The last two authors thank the National Science Foundation for financial support.