Optimal freeware quality in the presence of network externalities: an evolutionary game theoretical approach

New software products often face difficulty in achieving market penetration. A potential remedy is to offer a freeware version of the software to encourage initial adoption and establish a larger user base for the software, thereby increasing the commercial version's value to adopters in future periods. However, to avoid complete cannibalization of the commercial version, the freeware version's quality must be sufficiently low and the price of the commercial version must not be too high. We model the effect of these two decision variables, price and freeware quality, on the adoption of software using static and evolutionary game theory.     

The welfare effect of quality degradation in the presence of network externalities

This paper examines how the presence of network externalities affects a monopolist's incentive for quality degradation and its welfare consequence. The software and Internet service industries provide our primary motivation. The network externality may lead to a Pareto-improving quality degradation that would not be realised in the absence of network externalities. However, it may also overturn a potentially Pareto-improving quality degradation to a welfare-reducing one, or result in the realisation of a welfare-reducing quality degradation that would be avoided without network externalities. We also endogenise the firm's forward and backward compatibility decisions between the original and degraded goods.     

Evolution of market shares with repeated purchases and heterogeneous network externalities

We investigate how market shares change when a new, superior technology exhibiting network externalities is introduced in a market initially dominated by an old technology. This is done under the assumption that consumers are heterogeneous in their valuation of technology quality and network externalities and that goods are not (perfectly) durable and thus have to be bought repeatedly. When both technologies are unsponsored, the old technology dominates when the quality difference is small, and it disappears when the quality difference is large. When the new technology is sponsored, the relationship between the quality difference and the long-run market share of the new technology is non-monotonic and the old technology always continues to exist.

Modeling IT relationship quality and its determinants: A potential perspective of network externalities in e-service

This article addresses the development of relationship quality in the service context of information technology (IT) based on the network externalities theory. The model predicates the IT relationship quality is influenced by both synchronization value and autarky value, whereby autarky value is influenced by the availability of complementary goods. At the same time, synchronization value is influenced by relationship commitment and perceived critical mass, while availability of complementary goods is influenced by perceived compatibility and overall installed base. Note that the autarky value represents the value generated by the product itself even if there are no other users (e.g., the printing and copying functions of a fax/printer machine), while synchronization value represents individuals’ perceived value obtained through interaction (e.g., chatting functions of Skype). The model is examined using data obtained from employees of different companies in Taiwan. The empirical findings and their implications are discussed herein.     

Optimal taxation, global externalities and labor mobility

This paper concerns transboundary environmental problems in the context of an optimal tax model. We assume that part of the labor force is mobile across countries, and that the set of tax instruments includes a nonlinear income tax and a commodity tax on the ‘dirty’ good that is causing damage to the environment. The purpose is to compare the (globally optimal) second best policy of a cooperative equilibrium with the policy implicit in a noncooperative equilibrium. We show that the commodity taxes differ between equilibria because of: (i) transboundary externalities not internalized by national governments, (ii) interaction effects between environmental and other policies, and (iii) labor mobility.     

Network externalities and long-run market shares

We study a dynamic duopoly model with network externalities. The value of the product depends on the current and past network size. We compare the market outcome to a planner. With equal quality products, the market outcome may result in too little standardization (i.e. too many products active in the long run) but never too much. The potential inefficiency is non-monotonic in the strength of the network effect, being most likely for intermediate levels. When products differ in quality, an inferior product may dominate even when the planner would choose otherwise, but only if the discount factor is sufficiently large     

Competition in telecommunication networks with call externalities

This paper describes a model involving two interconnected networks offering different degrees of quality. In these networks, there are call externalities enabling consumers to assess the quality of the calls they send and receive. Networks compete in two-part tariffs. Our aim is to show that the “profit neutrality” result no longer applies due to network asymmetry and call externalities. In the case of non reciprocal access charges, call externalities generate private incentives enabling each competitor to charge low access prices. This reduces the risk of tacit collusion as competitors are free to negotiate their access charges.      

Agglomeration externalities: Marshall versus Jacobs

The literature remains inconclusive as to whether Marshallian specialization or Jacobian diversification externalities favor regional innovativeness. The specialization thesis asserts that regions with production structures specialized towards a particular industry tend to be more innovative in that particular industry, as it allows for knowledge to spill over between similar firms. The diversification thesis argues that knowledge spills over between different industries, causing diversified production structures to be more innovative. A closely related debate evolves around local competitiveness hypotheses. Using an original database of innovation counts, both these issues are addressed for the Dutch context. The results show that the Marshallian specialization thesis holds, though more pronounced for R&D intensive and small firms. Fierce local competition within an industry negatively affects innovativeness in that particular industry.JEL Classification: O18, O31, R10Gerben van der Panne: The author wishes to thank Fia Wunderink, Wilfred Dolfsma and Alfred Kleinknecht for helpful comments on an earlier version of this paper.     

A consumer-based model of competitive diffusion: the multiplicative effects of global and local network externalities

Competitive diffusion of two incompatible technologies, such as PC vs. Macintosh, VHS vs. Betamax and so on, is studied under the framework of a spatial game in which consumers are distributed on a two-dimensional square lattice network. The consumers play coordination-like games with their nearest neighbors and imitate the most successful strategy in their neighborhood in terms of aggregated payoffs after each round. The effects of global network externality are realized in the dynamic payoff matrix of the game, and the framework of spatial game provides the model with the effects of local network externality. These two types of externalities are set as multiplicative, that is, as nonlinear. Both simulations and mean-field approximation show that not only total but also partial standardization (robust polymorphic equilibrium) occurs depending upon the parameters and initial configurations, even when there are positive effects of both global and local network externalities. Moreover, effects of innovation factors that alter paths toward a lock-in situation are studied. It is shown that both the timing and the size of the innovation factors matter for a disadvantaged technology in order to overwhelm a market.JEL Classification: C7, D8, O3We are obliged to Professor John Paul Boyd at the University of California, Irvine and our anonymous referees for their constructive comments.     

Ecosystems,externalities, and economies

This paper incorporates an ecosystem model into a model of a simple economy. The decisionmaking agents in the ecosystem are individual organisms aggregated to the species level. A species may provide utility directly to humans, or it may provide utility indirectly because it is used either as a raw material in goods fabrication or as sustenance for other species. We describe a comparative static equilibrium of the ecosystem where species' demands for other species are equal to the supplies of those other species, and energy is conserved. The ecosystem is then embedded in the economy so that the effects of human intervention can be traced through both the ecosystem and the economy. Human intervention creates ecosystem externalities such that ecosystem equilibria are shifted and the new equilibria affect the utility or the production processes of other humans. This framework allows us to describe in principle which ecosystem services can be efficiently usurped by humans, which waste flows can be efficiently allowed into ecosystems, and which ecosystem organisms and physical attributes can be efficiently maintained.     

Farsighted strategies in the formation of a communication network

I examine the formation of a specific communication network, a variant of the two-way flow model, in which agents have farsighted strategies. I show that the likelihood to form efficient networks tends to zero for sufficiently large network sizes.     

Theory of negative consumption externalities with applications to the economics of happiness

This paper investigates the problem of obtaining Pareto efficient allocations in the presence of negative consumption externalities. In contrast to the conventional wisdom, we show that even if consumers’ preferences are monotonically increasing in their own consumption, one may have to dispose of resources to achieve Pareto efficiency when negative consumption externalities exist. We provide characterization results on destruction both for pure exchange economies and for production economies. As an application, our results provide an explanation to Easterlin’s paradox: average happiness levels do not increase as countries grow wealthier. We thank an anonymous referee, Xiaoyong Cao, Li Gan, and Tapan Mitra for helpful comments and suggestions that improved the exposition of the paper. The first author thanks the National Natural Science Foundation of China and Private Enterprise Research Center at Texas A&M University for financial support.     

Convergence speed and preference externalities in a one-sector model with elastic labor supply

In a one-sector model with elastic labor supply where consumption and leisure externalities are incorporated, we examine the impact of preference externalities on convergence speed.     

Structural change in the presence of network externalities: a co-evolutionary model of technological successions

The paper uses a two-stage, multi-agent simulation model to examine the conditions under which technological successions can occur in the presence of network externalities. Data is used to identify a robust econometric model of the probability of succession. Four key factors are identified. First, the trade-off between higher direct utility from new technology goods and the network utility of old technology goods. Second, the relative innovative performance of new and old technology firms. Third, cost (price) differentials due to increasing returns in production. Fourth, the time old (new) firms have to develop their product designs prior to entry.JEL Classification: O30, C15 Correspondence to: Paul WindrumThe authors would like to thank Richard Nelson and Uwe Cantner for their helpful comments on an earlier draft of the paper, and for the comments provided by the anonymous referees. The usual disclaimers apply. The authors gratefully acknowledge supportive funding through SEIN-Project, European Commissions Framework 4 Programme (contract# SOEI-CT-98-1107) and through the Policy Regimes and Environmental Transitions (PRET) project funded by the Dutch Scientific Research Council (NWO).     

Endogenous fluctuations in unionized economies with productive externalities

Summary. We discuss the effects of unions on steady-state multiplicity and welfare, and on the existence of endogenous fluctuations. We consider an OG economy with productive capital externalities and we focus on underemployment equilibria. We find that for wide regions in the parameter space, including an arbitrarily small degree of externalities and a Cobb-Douglas technology, unions increase steady state employment and welfare, and local indeterminacy (sunspots) emerges. Moreover with a CES technology multiplicity of steady states is only possible in the presence of unions. Our results also show that the role of unions in shaping local dynamics and bifurcations depends on technology (externalities and factors substitutability).Received: 16 January 2002, Revised: 18 March 2004, JEL Classification Numbers: E32, J51, D60, D62. Correspondence to: Leonor ModestoThis paper is a much revised version of our former working paper Unions, Increasing Returns and Endogenous Fluctuations. Financial support from Fundação para a Ciência e Tecnologia under the POCTI, is gratefuly acknowledged.     

Consumption externalities with endogenous time preference

This paper shows that in a model with inelastic labor supply, consumption externalities have impacts on stationary consumption and capital. The key element in observing the effects of consumption externalities on stationary consumption and capital is the endogeneity of the time preference rate, which depends on future-oriented resources rather than on private consumption. We conclude that when individuals experience jealousy, they become more impatient, leading to a lower level of capital stock and a higher level of consumption relative to those of the social optimum, while when they experience admiration, these relationships are reversed. We examine an optimal tax policy that replicates the socially optimal path in the centrally planned economy. Finally, using numerical analysis we explore how this economy evolves through time.      

Mean-Gini analysis of stochastic externalities: The case of groundwater contamination

The mean-Gini approach is used to analyze stochastic externalities generated by agricultural production. The model addresses the problem of groundwater pollution caused by excessive fertilizer application. Inherent in the mean-Gini approach to expected utility maximization is a two-fold value: the simplicity of the two-parameter mean-variance model and satisfaction of necessary and sufficient conditions for stochastic dominance. Price and quantity policy recommendations to control externalities are formulated based upon the relative assessment of uncertainty by the regulatory authority and the farmers. Using the Gini as a measure of risk allows for the quantification of control policy measures under differentiated risk aversion and multiple sources of pollution. The model shows that when producers underestimate uncertainty, quota policies restricting fertilizer are more efficient than tax policies in reducing groundwater contamination.Work on this paper was carried out when visiting the University of Maryland. Financial aid for the work was provided by the USDA ERS-NRED under a cooperative agreement between the Department of Agricultural and Resource Economics, University of Maryland, and the USDA — Economic Research Service — Natural Resource Economics Division, I am grateful to John Miranowski and Darrell Hueth for that support. I am indebted as well to Lana Shalit, who helped me revise the paper.     

Consumption externalities, rental markets and purchase clubs

Summary. A premise of general equilibrium theory is that private goods are rival. Nevertheless, many private goods are shared, e.g., through borrowing, through co-ownership, or simply because one persons consumption affects another persons wellbeing. I analyze consumption externalities from the perspective of club theory, and argue that, provided consumption externalities are limited in scope, they can be internalized through membership fees to groups. Two important applications are to rental markets and purchase clubs, in which members share the goods that they have individually purchased.Received: 2 June 2003, Revised: 8 March 2004, JEL Classification Numbers: D11, D62.This paper was supported by the U.C., Berkeley Committee on Research, and the Institute of Economics, University of Copenhagen. I am grateful to Birgit Grodal for her collaboration on the theory that underlies this paper, and for her helpful and motivating comments about these particular extensions. I also thank Hal Varian, Doug Lichtman, Steve Goldman, Karl Vind, anonymous referees, and members of the Berkeley Microeconomics Seminar for discussion.     

Negative externalities and welfare improving preference changes

When the over-consumption of open access resources and congestible public goods generate negative externalities and social welfare losses, many individuals and environmental advocacy organizations offer as an alternative nongovernmental solution the adoption of new ecology sustaining preferences. This paper shows that exogenously inducing a change in preferences and the adoption of new externality internalizing preferences, which increase an individual's marginal rate of substitution between a private good and a good whose consumption imposes external costs on others, not only reduces the aggregate output of the negative externality but also produces an economic state that is socially superior to the initial state. Because it is based on both the initial and new preferences, the social superiority welfare criterion makes possible meaningful welfare comparisons of economic states generated by preference changes. A computational general equilibrium model is then used to simulate preference changes and to calculate the resulting allocative and welfare effects. The computer simulations reveal that important factors in the attainment of a socially superior state include (i) the particular characteristics of an individual's negative externality reaction function, (ii) the magnitude of the preference change, and (iii) the number of individuals changing preferences.