optimal interest rate rules asset prices and credit frictions we study optimal taylor type interest rate rules in an economy with credit market imperfections our analysis builds on the agency cost framework of carlstrom and fuerst 1997 agency costs net worth and business fluctuations a computable general equilibrium analysis american economic review 87 893 910 which we extend in two directions first we embed monopolistic competition and sticky prices second we modify the stochastic structure of the model in order to generate a countercyclical premium on external finance this is achieved by linking the mean distribution of investment opportunities faced by entrepreneurs to aggregate total factor productivity we model monetary policy in terms of simple welfare maximizing interest rate rules we find that monetary policy should respond to increases in asset prices by lowering interest rates however when monetary policy responds strongly to inflation the marginal welfare gain of responding to asset prices vanishes within the class of linear interest rate rules that we analyze a strong anti inflationary stance always attains the highest level of welfare

patent pools as a solution to efficient licensing of complementary patents some experimental evidence production requiring licensing groups of complementary patents implements a coordination game among patent holders who can price patents by choosing among combinations of fixed and royalty fees summed across patents these fees become the total producer cost of the package of patents royalties because they function as excise taxes add to marginal costs resulting in higher prices and reduced quantities of the downstream product and lower payoffs to the patent holders using fixed fees eliminates this inefficiency but yields a more complex coordination game in which there are multiple equilibria which are very fragile in that small mistakes can lead the downstream firm to not license the technology resulting in inefficient outcomes we report on a laboratory market investigation of the efficiency effects of coordinated pricing of patents in a patent pool we find that pool like pricing agreements can yield fewer coordination failures in the pricing of complementary patents

collateral damage for r d manufacturers how patent sharks operate in markets for technology patent sharks small firms that exploit information asymmetries in markets for technology to gain patent based competitive advantages challenge established theory by which i markets for technology benefit large firms and ii intellectual property rights systems strictly support markets for technology empirically linking the sharks different assault strategies to the patents they deploy we illustrate that patent sharks will likely be an enduring phenomenon in markets for technology we discuss policy and strategy implications copyright 2010 the author 2010 published by oxford university press on behalf of associazione icc all rights reserved oxford university press

the ir relevance of real wage rigidity in the new keynesian model with search frictions we explore the role of real wage dynamics in a new keynesian business cycle model with search and matching frictions in the labor market both job creation and destruction are endogenous we show that the model generates counterfactual inflation and labor market dynamics in particular it fails to generate a beveridge curve vacancies and unemployment are positively correlated introducing real wage rigidity leads to a negative correlation and increases the magnitude of labor market flows to more realistic values however inflation dynamics are only weakly affected by real wage rigidity this is because of the presence of labor market frictions which generate long run employment relationships the measure of real marginal cost that is relevant for inflation dynamics via the phillips curve contains a dynamic component that does not necessarily move with real wages

credible spatial preemption it is often argued that incumbent firms may deter entry by preemptive investment in new goods we show that these conclusions are reversed when multiproduct incumbentfirms may exit in response to entry once entrants are in an industry an incumbent will often want to withdraw some goods to prevent competition with the entrant from reducing profits on other goods such a reaction makes entry more attractive to a potential entrant the equilibrium industry structure is less likely to be monopolistic as the goods are better substitutes as exit costs are low and as the competition between producers of the same good is more intense

patent pools litigation and innovation this article analyzes patent pools and their effects on litigation incentives overall royalty rates and social welfare when patent rights are probabilistic and can be invalidated in court with probabilistic patents the license fees reflect the strength of the patents we show that patent pools of complementary patents can be used to discourage infringement by depriving potential licensees of the ability to selectively challenge patents and making them committed to a proposition of all or nothing in patent litigation if patents are sufficiently weak patent pools with complementary patents reduce social welfare as they charge higher licensing fees and chill subsequent innovation incentives

standard essential patents a major policy issue in standard setting is that patents that are ex ante not that important by being included into a standard may become standard essential patents in an attempt to curb the monopoly power that they create most standard setting organizations require the owners of patents covered by the standard to make a loose commitment to grant licenses on reasonable terms such commitments unsurprisingly are conducive to litigation this paper builds a framework for the analysis of these patents identifies several types of inefficiencies attached to the lack of price commitments and shows how structured price commitments restore competition and why such commitments may not arise spontaneously in the marketplace

the direction of innovation abstract how do innovation policies affect the direction of research is market based innovation too radical or too incremental we construct a novel and tractable model of the direction of innovation firms pursue inefficient research directions because they race to discover easy yet less valuable projects and because they work on difficult inventions where they can appropriate a larger portion of the social value fixing these inefficiencies requires policy to condition on properties of inventions that could have been discovered but were not policies which do not do so like patents and prizes may fail to encourage firms to research in the efficient direction even if they obtain the optimal quantity of r d

competitive search equilibrium in this paper i construct an equilibrium for markets with frictions which is competitive in the sense that all agents are price takers and maximize utility subject to a set of market parameters i show that the equilibrium allocation is socially optimal i also show how the competitive search equilibrium can be achieved if employers with vacancies can advertise publicly the wages they pay

welfare cost of fluctuations when labor market search interacts with financial frictions we provide a quantitative assessment of welfare costs of fluctuations in a search model with financial frictions the matching process in the labor market leads positive shocks to reduce unemployment less than negative shocks increase it we show that the magnitude of this non linearity is magnified frictions this asymmetric effect of the business cycle leads to sizable welfare costs the model also accounts for the responsiveness of the job finding rate to the business cycle as financial frictions endogenously generate counter cyclical opportunity costs of opening a vacancy and wage sluggishness

job destruction and propagation of shocks this paper considers propagation of aggregate shocks in a dynamic general equilibrium model with labor market matching and endogenous job destruction cyclical fluctuations in the job destruction rate magnify the output effects of shocks as well as making them much more persistent interactions between capital adjustment and the job destruction rate play an important role in generating persistence propagation effects are shown to be quantitatively substantial when the model is calibrated using job flow data incorporating costly capital adjustment leads to significantly greater propagation

search theoretic models of the labor market a survey we survey the literature on search theoretic models of the labor market we show how this approach addresses many issues including the following why do workers sometimes choose to remain unemployed what determines the lengths of employment and unemployment spells how can there simultaneously exist unemployed workers and unfilled vacancies what determines aggregate unemployment and vacancies how can homogeneous workers earn different wages what are the tradeoffs firms face from different wages how do wages and turnover interact what determines efficient turnover we discuss various modeling choices concerning wage determination and the meeting process including recent models of directed search

credit market imperfections labor markets and leverage dynamics in emerging economies abstract emerging economies emes have different credit and labor market structures relative to advanced economies we document that economies with larger self employment shares tend to exhibit less countercyclical leverage dynamics we build a model where formal credit markets input credit relationships and the structure of labor markets interact that 1 captures a comprehensive set of eme business cycle regularities and 2 rationalizes our new fact the interaction between firms net worth interfirm input credit and self employment underlying our framework is critical for explaining our fact and is supported by the data

a comparison of nonparametric tests of weak separability for annual and quarterly data on consumption leisure and money among the most fundamental assumptions made in economics are utility maximization and the separability of the arguments in the representative consumer s utility function these assumptions are important for theoretical and empirical applications of economics in this article we present results from nonparametric tests of these assumptions of consumer behavior we find that utility maximization generally obtains with either annual or quarterly per capita data on consumption goods leisure and relatively liquid monetary assets annual data on consumption goods leisure and all monetary assets are consistent with utility maximization there is some evidence in support of using partial adjustment models when estimating quarterly data models of the demand for monetary assets further annual data on consumption goods and leisure and on liquid monetary assets meet the necessary and sufficient conditions for weak separability these results support the notion of a monetary aggregate more broadly based than cu

innovation policy for directing technical change in the power sector this paper discusses policy instruments for redirecting technical change within the electricity sector to mitigate climate change first we unravel the mechanism behind directed technical change explaining why markets may underprovide innovations in expensive renewable technologies in comparison to innovations in energy efficient fossil fuel generators subsequently we characterize technical change in electricity generation technologies stressing the heterogeneity of knowledge spillovers both within and between clean electricity generation technologies we argue that there exists a rationale for a portfolio approach to innovation in the electricity sector i e optimal innovation policies are neither fully generic nor fully specific and they need to be adapted in response to new information learned by the government the existing innovation literature does not however provide a clear cut answer for designing such a policy we compare policy instruments and argue that public r d support to clean technologies either in the form of subsidies or prizes seems to be the prime candidate for implementing non generic innovation policy

damages and injunctions in protecting intellectual property we investigate how liability rules and property rules protect intellectual property infringement might not be deterred under any of the enforcement regimes available however counterintuitively a credible threat of infringement can actually benefit the patentholder we compare the two doctrines of damages lost profit lost royalty and unjust enrichment and argue that unjust enrichment protects the patentholder better than lost royalty in the case of proprietary research tools both can be superior to a property rule depending on how much delay is permitted before infringement is enjoined for other proprietary products end user products cost reducing innovations these conclusions can be reversed

licensing policy and technology adoption in standard setting organizations the standard setting organizations decisions on licensing policy and standard s technological specification and the ensuing implications for social welfare are analyzed the author finds the conditions under which a licensing rule that grants monopoly power to the licensors whose technology is adopted in the standard can be employed by the members of the consortium ex post licensing moreover it is shown that the adoption of ex post licensing might lead to the inefficient exclusion of an efficient stand alone licensor finally the author discusses the conditions under which a policy of ex ante licensing can be less efficient than ex post licensing jel k21 l15 l24 l42

efficient patent pools the paper builds a tractable model of patent pools agreements among patent owners to license sets of their patents it provides a necessary and sufficient condition for patent pools to enhance welfare and shows that requiring pool members to be able to independently license patents matters if and only if the pool is otherwise welfare reducing the paper allows patents to differ in importance asymmetric blocking patterns and licensors to also be licensees we undertake some initial exploration of the impact of pools on innovation the analysis has broader applicability than pools being relevant to a number of co marketing arrangements

lending relationships and labor market dynamics abstract motivated by a negative link between credit spreads and labor force participation lfp and a positive link between these spreads and unemployment over the business cycle we study the role of lfp as an amplification mechanism of financial shocks in a labor search model with endogenous lfp lending relationships and credit market disruptions amid aggregate productivity and financial shocks that replicate the empirical volatility of lfp and credit spreads the model produces highly volatile unemployment and vacancies countercyclical credit spreads and unemployment and procyclical lfp when we quantitatively match the cyclical behavior of credit spreads the interaction between endogenous lfp and financial shocks gives rise to much sharper vacancy fluctuations and plays a key role in generating quantitatively factual cyclical labor market dynamics

shared patent rights and technological progress we study how to reward innovators who build on one another rewards come in the form of patents because patent rights are scarce the optimal allocation involves sharing more than one innovator s patent is in force at a given time we interpret such allocations as patents that infringe one another as licensing through an ever growing patent pool and as randomization through litigation we contrast the rate of technological progress under the optimal allocation with the outcome if sharing is prohibitively costly avoiding sharing initially slows progress and leads to a more variable rate of technological progress

job matching and propagation in the u s labor market the vacancy unemployment ratio and employment react sluggishly to productivity shocks we show that the job matching model in its standard form cannot reproduce these patterns due to excessively rapid vacancy responses extending the model to incorporate sunk costs for vacancy creation yields highly realistic dynamics creation costs induce entrant firms to smooth the adjustment of new openings following a shock leading the stock of vacancies to react sluggishly

the substitutability of equities and consumer durable goods a portfolio choice approach the stock market crash of october 1987 led many economists to lower their forecast of gnp growth for 1988 the rationale was that the loss of wealth that resulted from the crash would force asset holders to reduce their consumption expenditures yet a major slowdown in economic growth was not realized in the months following the crash gamer 11 explains this fact in terms of the life cycle hypothesis of consumption he argues that the potential adverse effect of stock market losses on planned consumption would be spread out over the entire lifetime of asset holders so that the immediate effect of the crash on the level

financial intermediation business failures and real business cycles in this paper a general equilibrium business cycle model is construct ed that when subjected to real disturbances mimics observed qualita tive comovements among real output money business failures risk pr emia intermediary loans and prices in contrast monetary disturban ces generate cycles that have several inconsistencies with empirical evidence thus providing support for real business cycle theory at th e expense of monetary theories of the business cycle financial inter mediation arises endogenously in the model and intermediation matters for business cycle behavior a credit supply mechanism acts in tande m with an intertemporal substitution effect in propagating stochastic disturbances copyright 1987 by university of chicago press

emerging ways to address the reemerging conflict between patenting and technological standardization the relationship between standards and intellectual property rights iprs is a complementary but troubled one the way it is managed affects the way stakeholders contribute to standards and may ultimately affect the way some technologies and even industries evolve a spate of recent legal controversies has been accompanied by the emergence of new mechanisms to help govern the risk of conflict here this article provides an empirical analysis of these attempts to reconcile the aims of these regimes

patent pool formation and scope of patents basic innovations are often fundamental to the development of applications that may be developed by other innovators in this setting we investigate whether patent pools can rectify the lack of incentives for a developer to invest in an application following green and scotchmer 1995 we also wonder whether broad basic patents are necessary in order to provide enough incentives for basic innovators we show that patent pools are more likely

cross licensing and competition we study bilateral cross licensing agreements between n 2 firms that engage in competition after the licensing phase it is shown that the most collusive cross licensing royalty i e the one that allows the industry to achieve the monopoly profit is sustainable as the outcome of bilaterally efficient agreements in a symmetric setting if the terms of the cross licensing agreements are not observable to third parties the monopoly royalty is the unique symmetric bilaterally efficient royalty however when the terms of the agreements are public the most competitive royalty i e zero can also be bilaterally efficient policy implications regarding the antitrust treatment of cross licensing agreements are derived from these results

patents and cumulative innovation causal evidence from the courts cumulative innovation is central to economic growth do patent rights facilitate or impede such follow on innovation this paper studies the effect of removing patent protection through court invalidation on the subsequent research related to the focal patent as measured by later citations we exploit random allocation of judges at the u s court of appeal for the federal circuit to control for the endogeneity of patent invalidation we find that patent invalidation leads to a 50 percent increase in subsequent citations to the focal patent on average but the impact is highly heterogeneous patent rights appear to block follow on innovation only in the technology fields of computers electronics and medical instruments moreover the effect is entirely driven by invalidation of patents owned by large patentees that triggers entry of small innovators suggesting that patents may impede the democratization of innovation

the new patent intermediaries platforms defensive aggregators and super aggregators some assets are traded in liquid markets at transparent prices with the help ome assets are traded in liquid markets at transparent prices with the help of many thriving intermediaries houses and apartments stocks and other of many thriving intermediaries houses and apartments stocks and other fi nancial products books dvds electronics and all sorts of collectibles fi nancial products books dvds electronics and all sorts of collectibles

patent pools and cross licensing in the shadow of patent litigation this paper develops a framework to analyze the incentives to form a patent pool or engage in cross licensing arrangements in the presence of uncertainty about the validity and coverage of patents that makes disputes inevitable it analyzes the private incentives to litigate and compares them with the social incentives it shows that pooling arrangements can have the effect of sheltering invalid patents from challenges this result has an antitrust implication that patent pools should not be permitted until after patentees have challenged the validity of each other s patents if litigation costs are not too large

tying foreclosure and exclusion in recent years the leverage theory of tied good sales has faced heavy and influential criticism in an important sense though the models used by its critics are actually incapable of addressing the leverage theory s central concerns here the author reconsiders the leverage hypothesis and argues that tying can indeed serve as a mechanism for leveraging market power the mechanism through which this leverage occurs its profitability and its welfare implications are discussed in detail copyright 1990 by american economic association

tax smoothing in frictional labor markets we re examine the optimality of tax smoothing from the point of view of frictional labor markets our central result is that whether or not this cornerstone optimal scal policy pre

optimal cross licensing arrangements collusion versus entry deterrence this paper analyzes optimal cross licensing arrangements between incumbent firms in the presence of potential entrants the optimal cross licensing royalty rate trades off incentives to sustain a collusive outcome vis a vis incentives to deter entry with the threat of patent litigation we show that a positive cross licensing royalty rate which would otherwise relax competition and sustain a collusive outcome dulls incentives to litigate against entrants our analysis can shed light on the puzzling practice of royalty free cross licensing arrangements between competing firms in the same industry as such arrangements enhance incentives to litigate against any potential entrants and can be used as entry deterrence mechanism

the price effects of international airline alliances abstract this paper provides evidence on the effect of international airline alliances on fares the main finding is that alliance partners charge interline fares that are approximately 25 percent below those charged by nonallied carriers according to our theoretical model the main source of this fare reduction is the internalization of a negative externality that arises from the uncoordinated choice of interline sub fares in the absence of an alliance the paper also looks for evidence of an anti competitive alliance effect in the gateway to gateway markets while the point estimates show that an alliance between two previously competitive carriers would raise fares by about 5 percent this effect is not statistically significant

how strong are weak patents economists usually conceive of patents as property rights that prevent others from practicing the patenting technology unless they first obtain a license from the patent holder even for ironclad patents i e for patents that are certain to be valid the existing literature has shown that the analysis of equilibrium licensing contracts is surprising subtle and complex 1 for example the analysis is quite different depending upon whether one firm s licensing contract is observable to the other firms likewise equilibrium outcomes are quite different if royalties must be linear than in the case where two part tariffs and other non linear royalties are permitted in that literature a downstream firm that refuses to sign a contract with the upstream supplier either exits the industry in the case that the upstream supplier controls an essential input or must rely on more costly inputs in the case of a non essential input in other words the downstream firm s threat point is to use some backstop technology in practice however patents are issued after a brief examination by the patent office to see if they meet the statutory requirements for novelty and non obviousness mounting evidence indicates that many weak patents i e patents unlikely to be found valid if challenged in court are issued by the u s patent and trademark office uspto 2 some observers view this with great alarm arguing that uspto is handing out undeserved monopolies others by contrast have suggested that these weak patents are of little concern because they will have little commercial impact because they will be licensed at commensurately low royalty rates or not enforced at all we study the commercial impact of weak patents more precisely we define a patent s strength as the probability that it will be found valid if challenged in court and we examine the relationship between a patent s strength and the royalties that it can command the distinctive

differentiated standards and patent pools we consider patent pool formation by owners of essential patents for differentiated standards that may be complements or substitutes in use pooling improves coordination in terms of royalty setting within a standard but provokes a strategic response from licensors in the competing standard we characterise the incentives to form and defect from pools within standards and show how pool formation and stability depend on competition between standards we also examine strategic patent pool formation by consortium standards and show that policies promoting compatibility of standards may increase or decrease welfare depending on the effects on the incentives to form pools

the unemployment volatility puzzle is wage stickiness the answer i discuss the failure of the canonical search and matching model to match the cyclical volatility in the job finding rate i show that job creation in the model is influenced by wages in new matches i summarize microeconometric evidence and find that wages in new matches are volatile and consistent with the model s key predictions therefore explanations of the unemployment volatility puzzle have to preserve the cyclical volatility of wages i discuss a modification of the model based on fixed matching costs that can increase cyclical unemployment volatility and is consistent with wage flexibility in new matches

the external finance premium and the macroeconomy us post wwii evidence abstract the central variable of theories of financial frictions the external finance premium is unobservable this paper distils the external finance premium from a dynamic stochastic general equilibrium dsge model estimated on us macroeconomic data covering the period 1954 to 2004 within the dsge framework movements in the premium can be given an interpretation in terms of shocks driving business cycles a key result is that the estimate based solely on non financial macroeconomic data picks up over 70 of the dynamics of lower grade corporate bond spreads the paper also identifies a gain in fitting key macroeconomic aggregates by including financial frictions in the model and documents how shock transmission is affected

patents and innovation evidence from economic history abstract what is the optimal system of intellectual property rights to encourage innovation empirical evidence from economic history can help to inform important policy questions that have been di

patent pools and innovation in substitute technologies evidence from the 19th century sewing machine industry patent pools which combine complementary patents of competing firms are expected to increase overall welfare but potentially discourage innovation in substitutes for the pool technology this article exploits a new historical data set on changes in patenting and firm entry for a clearly defined pool technology and substitutes in the 19th century sewing machine industry this analysis reveals a substantial increase in innovation for an albeit technologically inferior substitute technology historical evidence suggests that the creation of a pool diverted innovation toward an inferior substitute technology by creating differential license fees and litigation risks

business cycles and labor market search the quantitative implications of labor market search for economic fluctuations are evaluated in the context of a real business cycle model incorporating labor market search into the model is found to improve its empirical performance along several dimensions in particular hours now fluctuate substantially more than wages and the contemporaneous correlation between hours and productivity falls in addition the model replicates the observation that output growth displays positive autocorrelation at short horizons overall the empirical results suggest that the labor market search environment embodies a quantitatively important propagation mechanism copyright 1996 by american economic association

costly external finance and labor market dynamics abstract we study the role of agency frictions and costly external finance in cyclical labor market dynamics with a focus on how credit market frictions may amplify aggregate tfp shocks the main result is that aggregate tfp shocks lead to large fluctuations of labor market quantities if the model is calibrated to the empirically observed countercyclicality of the finance premium a financial accelerator mechanism thus amplifies labor market fluctuations by rendering rigidity in real wage dynamics in contrast if the finance premium is procyclical which the model can be parameterized to accommodate amplification is absent and labor market fluctuations display the shimer 2005 puzzle

monetary policy and labor market frictions a tax interpretation replicating the flexible price allocation in models with nominal rigidities and labor market frictions that lead to an inefficient matching of unemployed workers with job vacancies even if feasible is generally not desirable we characterize the tax instruments that implement the first best allocation and examine the trade offs faced by monetary policy if these tax instruments are unavailable our tax interpretation helps explain why the welfare cost of inefficient labor market search can be large while the incentive to deviate from price stability is small gains from deviating from price

nonparametric tests of utility maximization and weak separability for consumption leisure and money some of the most fundamental assumptions of economics are utility maximization and weak separability of the arguments in the represen tative consumer s utility function this paper contains results from nonparametric tests of these assumptions about consumer behavior the authors find that quarterly per capita data on consumption goods le isure and monetary assets are consistent with utility maximization further consumption goods and leisure meet necessary and sufficient conditions for weak separability additionally one grouping of relat ively liquid monetary assets meets the necessary conditions for weak separability they also test and find no evidence of homothetic prefe rences copyright 1987 by mit press

the role of patents in information and communication technologies a survey of the literature during the last few decades the number of patents in information and communication technologies has increased considerably an increasing number of patents and the associated fragmentation of ip rights have generated a series of potentially problematic consequences patent thickets royalty stacking the emergence of patent assertion entities increased patent litigation particularly around standard essential patents and the difficulties with defining fair reasonable and nondiscriminatory licensing terms are some of the most debated issues in the literature that we review in this paper we devote a specific section of our survey to patent quality currently one of the most debated issues surrounding the patent system in our analysis we mix theoretical and empirical arguments with a more policy oriented reasoning this allows us to better position the different issues in the relevant political and economic context

should good patents come in small packages a welfare analysis of intellectual property bundling abstract intellectual property owners often hold the rights to several patents each of which is essential to make or use a product we compare the welfare properties of package licenses under which a licensee pays the same fee regardless of the number of technologies licensed with component licenses under which each technology is licensed separately and there is no quantity discount a central finding is that a long term package license can induce incentives to invent around patents and invest in complementary assets that are closer to their socially optimal levels than are those induced by a long term component license we also identify settings in which a short term license is a partial substitute for a package license and a prohibition on package licensing induces parties to adopt contracts that result in less efficient complementary investment because of hold up

borrowing constraints collateral fluctuations and the labor market abstract this paper studies the effects of changes in collateral requirements on the cyclical properties of unemployment and job creation i develop a general equilibrium model in which labor market frictions prevent the costless adjustment of employment financial frictions arise from an imperfect enforcement contract an environment in which borrowing limits are linked to the firm s physical capital stock can quantitatively account for the sluggish response of labor market variables to productivity shocks i find that fluctuations in those variables are mainly driven by changes in financial conditions the model can explain 75 of the variation in job creation observed in the data and it can also account for the persistent reduction in both output and leverage that follows a contraction in credit availability

do patents work thickets trolls and antibiotic resistance this paper connects ideas from recent literature on the economics of intellectual property ip to address the question did the strengthening and broadening of ip rights from important patent policy changes in the us promote greater innovation the analysis rests on the theory of cumulative innovation which shows that if ip rights on a pioneer invention extend to follow on research and impediments to contracting exist then strengthening patents can actually reduce overall innovation recent empirical studies are consistent with the theory patents can significantly deter follow on research in complex technology areas where contracting is difficult computers electronics telecommunications but not in drugs chemicals and human genes i outline remedies from court decisions and antitrust policy for addressing inefficiencies from patent trolling patent thickets and the anti commons of fragmented ownership i then apply the analysis to the antibiotics market drawing on recent research to examine how patent and competition policies can be used to improve incentives for drug development in the battle against antibiotic resistance the literature provides persuasive evidence that the policy changes overreached in broadening and strengthening ip rights and reveals important patent reforms for improving the effectiveness of patent systems in the us and canada

entry for buyout the possibility of buying out an entrant has an important effect on entry deterrence entrants can blackmail the incumbent by threatening to keep prices low and buyout can make entry profitable which otherwise would not be in particular the entry deterrence policy of excess capacity to reduce the post entry price can not only fail but work against the incumbent the presence of multiple oligopolistic incumbents or multiple potential entrants however can discourage entry for buyout the long literature on entry deterrence has always assumed that if entry is made unprofitable no entry will occur but as followers of professional football may have suspected a clearly unprofitable competitor might rationally enter a market in the hopes of selling out to the incumbent i will model such a situation and try to show what conditions facilitate entry for buyout in the simplest entry deterrence model the incumbent successfully maintains monopoly by threatening to expand output and cut price after other firms enter but he succeeds only because potential entrants believe the threat if entrants are rational this strategy fails price warfare hurts the incumbent as well as the entrant so the monopolist would let the entrant have a share of profits after entry potential entrants foreseeing the accommodating response ignore the threat deterred entry is a nash equilibrium but not a perfect nash equilibrium it is nash because the entrant chooses to stay out given the incumbent s strategy of cutting prices after entry and the incumbent does not mind committing himself to cutting prices given that entry never occurs a perfect nash equilibrium is a set of strategies that is a nash equilibrium for every proper subgame if the game is started at any of the nodes of the game tree including those off the equilibrium path the strategies the agents pick to maximize their objective function from that node onwards must be part of the equilibrium strategy for the entire game in the subgame which begins after entry has already occurred the incumbent would not choose to cut prices so cutting prices after entry is not part of a perfect equilibrium in the perfect equilibrium entry occurs and is accommodated