supply shocks in a two country world with wage and price rigidities the implications of quantity adjustments in the face of sticky prices in open economy macroeconomic models have been introduced by dixit i978 neary i980 and dixit and norman i980 the first two employ the small country assumption that the foreign price level is an exogenous variable with the latter including a non traded good into the discussion dixit and norman introduce a two country one good model and only consider a generalised keynesian outcome under fixed exchange rates in this paper we analyse a two country two good model and consider the international link between unemployment in both countries with special emphasis on supply shock originated disequilibria under fixed and flexible exchange rates naturally the terms of trade become an important transmission mechanism in a two good model under flexible exchange rates the work of barro and grossman i976 malinvaud i977 et al for closed economies has shown that temporary equilibria in a closed economy can be classified into regions of keynesian unemployment classical unemployment repressed inflation and under consumption when two countries linked by trade are discussed the classification of international temporary equilibria multiplies accordingly we choose a small subset of these possibilities focusing on those that are likely to be associated with supply shocks i e combinations of keynesian and classical unemployment two country models have been extensively studied under walrasian and simple keynesian specifications see for instance laursen and metzler i950 harberger i95i meade i95i mundell i968 swoboda and dornbusch i973 and mussa i979 we consider these models briefly in section iii emphasising their micro foundations and general equilibrium properties stability of both fixed and flexible exchange rates regimes for walrasian and keynesian equilibria revolves around some form of the marshall lerner conditions being satisfied the problem of competitive devaluations to export unemployment in a keynesian world is discussed while a keynesian outcome for both countries applies for some configurations of wages and product prices and exchange rates this is not true for all configurations hence with sticky prices monetary deflation in both countries should lead to keynesian unemployment in both but when negative supply shocks reduce national labour demands and output supplies keynesian aggregate demands cease to determine the levels of economic activity and employment appropriately

endogenous growth and the possibility of eliminating pollution abstract this paper studies the effect on optimal growth of the possibility that at some moment in the future a technology is discovered that eliminates pollution we formalize this possibility as a probability p per unit of time of discovering such a technology we focus on steady state behavior and show that the optimal rate of growth increases with the hope of eliminating pollution for an economy where there is no growth in the steady state of the optimal trajectory when p 0 a positive p may imply positive growth the higher the value of the probability the larger the endogenous rate of growth

aspects of labor market adjustments in japan this article discusses some aspects of labor market adjustments in japan that may be relevant to the low unemployment rate there japanese statistics treat kyugyosha persons not at work as being employed but some of these workers would be counted as unemployed in the united states the kyugyosha group appears to increase in size during downturns and decreases during upturns suggesting that temporarily laid off persons are an important part of this group japanese employers evidently rely less on employment adjustments and more on adjustments in hours of work and inventory while employers in the united states rely more on employment adjustments to deal with cyclical changes in product demand japanese manufacturing employment became less sensitive and hours of work more sensitive to demand shocks after the introduction of the employment insurance law in 1975

green goals and full employment are they compatible abstract two empirical correlations are studied one between economic growth and environmental impacts and the other between the lack of economic growth and unemployment it is demonstrated that at a global level economic growth is strongly correlated with environmental impacts and barriers to fast decoupling are large and numerous on the other hand low or negative growth is highly correlated with increasing unemployment in most market economies and strategies to change this lead to difficult questions and tradeoffs the coexistence of these two correlations which have rarely been studied together in the literature on green growth degrowth and a growth justifies ambivalence about growth to make key environmental goals compatible with full employment the decoupling of environmental impacts from economic output has to be accompanied by a reduction of dependence on growth in particular strategies to tackle unemployment without the need for growth several of which are studied in this article need much more attention in research and policy

keynesian and classical unemployment in an open economy this paper examines various unemployment equilibria in a fix price model of an open economy with nontraded goods the economy exports an internationally traded good and imports an intermediate input good the comparative static effects of various exogenous variables on total employment and the balance of trade are derived and compared across regimes considerable emphasis is placed on the employment effects of external disturbances both price shocks such as a rise in the price of the imported intermediate good and quantity shocks e g a slump in the demand for exportables are examined and the appropriate policy for restoring full employment is discussed in each case

polluting non renewable resources and growth in an endogenous growth model with human capital accumulation we introduce non renewable resources which cause flow pollution problems in this set up the negative external effect of pollution on productivity does not cause any distortions in the economy the market economy will achieve the optimal extraction and growth rates consequently emission taxes are unnecessary and when introduced will have no effect on the economy the more important is the negative pollution externality the larger will be the optimal long run growth rate which may be either positive or negative in the case of a positive human capital externality consumption in the market economy may approach zero in the long run although positive consumption growth is socially optimal growth enhancing policies do not necessarily cause a larger drain in the resource stock

optimal pricing in networks with externalities we study the optimal pricing strategies of a monopolist selling a divisible good service to consumers who are embedded in a social network a key feature of our model is that consumers experience a positive local network effect in particular each consumer s usage level depends directly on the usage of her neighbors in the social network structure thus the monopolist s optimal pricing strategy may involve offering discounts to certain agents who have a central position in the underlying network our results can be summarized as follows first we consider a setting where the monopolist can offer individualized prices and derive a characterization of the optimal price for each consumer as a function of her network position in particular we show that it is optimal for the monopolist to charge each agent a price that consists of three components i a nominal term that is independent of the network structure ii a discount term proportional to the influence that this agent exerts over the rest of the social network quantified by the agent s bonacich centrality and iii a markup term proportional to the influence that the network exerts on the agent in the second part of the paper we discuss the optimal strategy of a monopolist who can only choose a single uniform price for the good and derive an algorithm polynomial in the number of agents to compute such a price third we assume that the monopolist can offer the good in two prices full and discounted and we study the problem of determining which set of consumers should be given the discount we show that the problem is np hard however we provide an explicit characterization of the set of agents who should be offered the discounted price next we describe an approximation algorithm for finding the optimal set of agents we show that if the profit is nonnegative under any feasible price allocation the algorithm guarantees at least 88 of the optimal profit finally we highlight the value of network information by comparing the profits of a monopolist who does not take into account the network effects when choosing her pricing policy to those of a monopolist who uses this information optimally

the macroeconomic implications of profit sharing some empirical evidence the macroeconomic implications of profit sharing some empiricals paper attempts an empirical assessment of weitzman s proposition that profit sharing provides an antidote to stagflation taking japan as an example of a profit sharing economy the author shows that it does not have either lower cyclical variability of output or lower inflation than other industrial countries the authors then reject the propositions that in a profit sharing economy 1 aggregate demand shocks have a smaller effect on output deviations and 2 import price shocks and wage push have a smaller effect on inflation therefore one should be wary of the claim that the japanese case supports weitzman s model copyright 1987 by royal economic society

does improved environmental policy enhance economic growth the environmental impacts on an economy is studied over time using endogenous growth theory externalities from the environment on production are central in the analysis and we examine whether an optimal path realizes more rapid economic growth the paper focuses mainly on developing countries where production is largely influenced by the environmental quality the result of the analysis indicates that the economic growth rate may not depend on the internalization of the environmental externality but rather on the internalization of the human capital externality the level of economic activity however generally seems to depend on the internalization of both externalities

growth and distribution interest in the determinants of the rate growth of different economies is as old as our subject itself book iii of adam smith s an inquiry into the nature and causes of the wealth of nations was subtitled of the different progress of opulence in different nations but the systematic formal modelling of growth took as its inspiration the proposition of harrod 1939 and domar 1946 that a steady state rate of growth was feasible only in fortuitous circumstances it was based on three main assumptions first the amounts of capital and labour needed to produce a unit of output are given by technological requirements in particular the capital output ratio denoted by u is a technological constant second the fraction of net income in the economy that is saved denoted by s is fixed finally potential output from given inputs of capital and labour grows at an exogenous rate determined by technical progress labour supply the only non produced input also grows at an exogenous rate hence the only feasible long run steady state rate of growth is the rate of technical progress plus the rate of population growth the natural rate of growth denoted by n stochastic shocks to potential output are ignored in this model much of equilibrium growth theory has been devoted to understanding the conditions necessary for individual saving and investment decisions to be compatible with the levels implied by the natural growth rate an equilibrium growth path is one along which planned net saving equals planned net investment denote the current level of output by y and the expected change in output by ak planned saving is equal to the product of the saving ratio and the level of net output sk planned investment is equal to the product of the capital output ratio and the expected change in output ijay the expected growth rate of output is ay y and in equilibrium this is equal to s v from the condition that planned saving equals planned investment when

a disequilibrium model with smooth regime transitions and a keynesian spillover for switzerland s labor market abstract this paper presents a disequilibrium labor market model in which aggregation over a continuum of micro markets with different demand supply ratios produces smooth macro relationships mapping aggregate demand and supply onto actual employment and regime proportions aggregate labor demand consists of a classical part derived on a putty clay assumption and a keynesian spillover from the goods market the specification of labor supply incorporates intertemporal substitution the degree of aggregate imbalances on labor and goods markets is measured by business survey data the estimated model indicates a growing mismatch between the micro structures of demand and supply of labor the short run fluctuations of employment are primarily traced back to the keynesian spillover classical determinants of labor demand are relevant as well but only in the medium term labor supply is rather inert and thus absorbs the swings of labor demand only partly

vertical product differentiation network externalities and compatibility decisions abstract we analyse the subgame perfect equilibrium of a four stage game in a model of vertical product differentiation where the consumer s evaluation of a product depends on its inherent quality and on its network s size first two firms choose their product s inherent quality then they may mutually agree on providing an adapter before competing in prices finally consumers buy we find that despite the high quality firm s preference for incompatibility an adapter is always provided in equilibrium social welfare is greater than without an adapter and can be improved by regulating compatibility only in those cases where qualities are differentiated too much

trends in unemployment wages and productivity the case of japan along with the high savings ratio the functioning of the labour market is one of the most important factors behind the macroeconomic performance of the postwar japan which foreign observers have christened the miracle of the rising sun in the first place the nature of the japanese labour market is important for the long run trend of japanese economic growth because labour and its quality are crucial factors for economic development the high quality of a well disciplined workforce as well as the migration of labour from rural to urban areas has contributed much to the rapid growth of the japanese economy second the nature of the labour market has influenced the pattern of japanese business cycles by buffering demand fluctuations the slow response of firms demand for labour combined with the fast response of the labour force participation ratio has prevented a sharp increase in the unemployment rate during recessions relatively flexible nominal and real wages have also enabled the japanese economy to adjust quite smoothly to supply shocks notably after the second oil crisis in this paper we shall review trends in unemployment wages and productivity in the postwar japanese economy and relate them to its macroeconomic performance we shall also summarize the current literature concerning features of the labour market evaluate quantitative estimates of trends in labour statistics and explore future prospects

hotelling bertrand duopoly competition under firm specific network effects abstract social pressure plays a crucial role in consumer choices the impact of network social effects has also been largely recognised in the context of market competition in this paper we consider a duopoly where competing firms are differentiated solely by the level of social or network externality they induce on consumers perceived utility we fully characterise nash equilibria in locations prices and market shares under a scenario of weak social externality firms opt for maximum differentiation and the firm with the highest social recognition enjoys a relative advantage in terms of profit this outcome is not the only possible we formally prove that large values of social recognition may lead to adverse coordination among consumers and move the strongest firm out of the market with positive probability this scenario is related to a pareto inefficient trap of no differentiation

remaining puzzles and neglected issues in macroeconomics this paper analyses the chain of transmission mechanisms of economic policy actions to financial markets output and employment and finally unemployment in an attempt to identify remaining puzzles and neglected issues in macroeconomics the paper emphasizes the consequences of fiscal and monetary policy actions on real variables including real interest rates and real exchange rates an attempt is made to explain why product demand shocks often tend to have faster effects on output and employment than on prices the paper also discusses why demand induced increases in output and employment are not systematically connected with a reduction in the product wage rate the paper ends with a discussion of various supply side considerations in macroeconomics

chicken and egg competition among intermediation service providers we analyze a model of imperfect price competition between intermediation service providers we insist on features that are relevant for informational intermediation via the internet the presence of indirect network externalities the possibility of using the nonexclusive services of several intermediaries and the widespread practice of price discrimination based on users identity and on usage efficient market structures emerge in equilibrium as well as some specific form of inefficient structures intermediaries have incentives to propose non exclusive services as this moderates competition and allows them to exert market power we analyze in detail the pricing and business strategies followed by intermediation services providers copyright 2003 by the rand corporation

structural unemployment and disequilibrium abstract in this paper we present a disequilibrium model of the labor market which allows us to distinguish cyclical unemployment due to wage rigidity from structural unemployment this is done through the insertion in the exchange condition of an aggregate disequilibrium model of variables measuring mismatch between disaggregated labor supplies and labor demands such a model also allows unemployment and job vacancies to coexist the model is estimated using canadian quarterly data from 1966 to 1983 our results imply that structural unemployment due to inter industrial shocks while significant is fairly small

monopoly pricing with network externalities abstract how should a monopolist price a durable good or a new technology that is subject to network externalities in particular should the monopolist set a low introductory price to attract a critical mass of adopters in this paper we provide intuition as to when and why introductory pricing might occur in the presence of network externalities incomplete information about demand or asymmetric information about costs is necessary for introductory pricing to occur in equilibrium when consumers are small

network competition ii price discrimination our companion article developed a clear conceptual framework of negotiated or regulated interconnection agreements between rival operators and studied competition between interconnected networks under the assumption of nondiscriminatory pricing this article relaxes this assumption and allows networks to charge different prices for calls terminating on the subscriber s network and those terminating on a rivals network this creates a price differential between services that are identical for the consumer and generates network externalities despite network interconnection we show that in both the mature and entry phases of the industry the nature of competition is substantially affected by such price discrimination

pricing in social networks we analyze the problem of optimal monopoly pricing in social networks where agents care about consumption or prices of their neighbors we characterize the relation between optimal prices and consumers centrality in the social network this relation depends on the market structure monopoly vs oligopoly and on the type of externalities consumption versus price we identify two situations where the monopolist does not discriminate across nodes in the network linear monopoly with consumption externalities and local monopolies with price externalities we also analyze the robustness of the analysis with respect to changes in demand and the introduction of bargaining between the monopolist and the consumer

bertrand competition under network externalities abstract two firms engage in price competition to attract buyers located on a network the value of the good of either firm to any buyer depends on the number of neighbors on the network who adopt the same good when the size of externalities increases linearly with the number of adoptions we identify the set of pricing strategies that are consistent with an equilibrium in which one of the firms monopolizes the market the set includes marginal cost mc pricing as well as bipartition pricing which offers discounts to some buyers and charges markups to others we show that mc pricing fails to be an equilibrium under non linear externalities in a general network but identify conditions for an equilibrium with bipartition pricing to be robust against perturbations in the externalities from linearity the analysis is applied to platform competition in a two sided market under local and approximately linear externalities

regional disparities and national similarities in spanish unemployment a case of seasonal cointegration short run fluctuations in unemployment could be interpreted as transitory movements away from a hypothetical equilibrium the problem apart from the existence of such equilibrium is the existence of an adjustment mechanism that ensures the convergence of the short towards the long run with quarterly data from the spanish labour market since 1975 we have estimated a vectorial error correction model that allows for precisely this convergence the objective was to investigate the variables that explain the two distinctive features of spanish unemployment its size and its persistence we have found that there is a cointegration relationship between unemployment and production proxied by several variables for this reason rather than hysteresis we have found a high persistence in spanish unemployment this persistence could be explained by regional mismatch that is lack of adjustment between demand and supply of labour in some spanish regions we have used regional data to find those common trends i

pricing network effects the increase in the information that firms can collect or purchase about network effects across consumers motivates two important questions how does a firm s pricing strategy react to detailed information on network effects are the availability and use of such information beneficial or detrimental to consumer surplus we develop a model in which a monopoly sells a network good and price discriminates based on information about consumers influence and consumers susceptibility to influence the monopoly optimally offers consumers price discounts for their influence and charges price premia for their susceptibility the price premia and the price discounts are simple functions of the pattern of network effects we determine under which conditions relative to uniform price consumer surplus increases and we characterize the value of information on network effects for the monopoly

heavily skewed pricing in two sided markets a common feature in two sided markets is the prevalence of heavily skewed pricing strategies in which price markups are much higher on one side of the market than the other we show that maximal skewed pricing is profit maximizing under constant elasticity of demand the most elastic side of the market is used to generate maximum demand by providing it with platform services at the lowest possible price full participation of the high elasticity low price side of the market attracts the other side as this side is less price elastic the platform is able to extract high prices

international transmission of environmental policy a new keynesian perspective in this paper we examine the international transmission of environmental policy using a new keynesian model of the global economy we first consider the case in which the quality of the environment affects utility but not productivity this allows us to look at the trade off between environmental quality and output we then consider the case in which the quality of the environment increases productivity but does not affect utility our main results show that in both cases a unilateral implementation of a more stringent environmental policy by the domestic country raises foreign welfare under a benchmark parameterization our modeling strategy allows an analysis of how nominal rigidities interact with the implementation of environmental reforms by allowing the domestic country to shift through exchange rate depreciation parts of the costs of more stringent environmental policies to the foreign one

coordinating adoption decisions under externalities and incomplete information abstract a monopolist sells a good whose value depends on the number of buyers who adopt it as well as on their private types the seller coordinates the buyers adoption decisions based on their reported types and charges them the price based on the number of adoptions we study ex post implementable sales schemes that are collusion proof and show that under the revenue maximizing scheme more buyer types are willing to adopt when there are more adoptions and the number of adoptions is maximized subject to the participation constraints

labor utilization and nonwage labor costs in a disequilibrium macro framework the literature on labor utilization and nonwage labor costs is extended to incorporate recent approaches to macroeconomic disequilibrium modeling based on the smoothing by aggregation principle this leads to a reformulation of the basic sneessens dreze type model by treating employment and working hours as separate inputs the inclusion of nonwage labor costs serves a double purpose first they represent a restriction in the profit maximizing process and second they serve as a proxy for the fixity of labor the results differ substantially from simulation studies that disregard the utilization of labor and the nonlinear structure of labor costs

labour supply and unemployment in japan abstract the paper investigated the relationship between labour supply and unemployment employment in japan the paper focused on the discouraged worker effect which specifies that a large number of workers in particular female labour forces retire from the labour market in a recession this lowers the rate of the published unemployment the paper estimated the labour supply function and presented the estimated figures of the modified or adjusted rate of unemployment finally the okun s coefficient was re estimated by using this modified rate of unemployment

local network externalities and market segmentation this paper models interaction between groups of agents by means of a graph where each node represents a group of agents and an arc represents bilateral interaction it departs from the standard katz shapiro framework by assuming that network benefits are restricted only amongst groups of linked agents it shows that even if rival firms engage in bertrand competition this form of network externalities permits strong market segmentation in which firms divide up the market and earn positive profits the analysis also shows that some graphs or network structures do not permit such segmentation while for others there are easy to interpret conditions under which market segmentation obtains in equilibrium c 2009 elsevier b v all rights reserved

the relationship between production and unemployment in japan okun s law in comparative perspective abstract this paper studies the question whether the celebrated okun s law a relation between excess capacity and unemployment applies to the postwar japanese economy though the fitness of estimation is weak the coefficient that measures the responsiveness of the output gap to the unemployment rate is very large reaching 28 this large coefficient can be attributed to the elastic response in the female participation ratio to flexible working hours to the slow adjustment in employment and to changes in industrial structures the results are compared with those in the united states

coordination and discrimination in contracting with externalities divide and conquer abstract the paper studies bilateral contracting between n agents and one principal whose trade with each agent generates externalities on other agents it examines the effects of prohibiting the principal from i coordinating agents on her preferred equilibrium and ii making different contracts available to different agents these effects depend on whether an agent is more or less eager to trade when others trade more the prohibitions reduce the aggregate trade in the former case and have little or no effect in the latter case the inefficiencies under different contracting regimes are linked to the sign of the relevant externalities and are shown to be typically reduced by both prohibitions

the real debt resistance hypothesis and persistence of unemployment in the oecd countries according to friedman 1968 p 10 unemployment above the natural rate should sooner or later lead to deflation and an accelerating deflation at that as table 1 shows until the mid 1980s the course of movement of the rate of unemployment and inflation in the oecd countries is in conformity with this hypothesis however since the mid 1980s and in spite of continuing high unemployment the rate of inflation remained at a significantly positive level there is certainly not evidence of accelerated deflation as predicted by friedman the most popular explanation offered is the possibility of presence of the hysteretic tendencies in the nairu three famous models in this respect are the insider outsider hypothesis of blanchard and summers 1986 the capacity constraint hypothesis of sneessens and dreze 1986 and the declining search effectiveness long term unemployment hypothesis of layard nickell and jackman 1991 all these explanations rely on the real wage rigidity as table 1 shows however the rigidity of real wages seems to be more due to the downward rigidity of the rate of growth of nominal wages and prices for example the average weekly earnings of the production workers in the us manufacturing sector has steadily increased since 1946 1 thus contrary to the dominant view in the new keynesian school see gordon 1990 what needs to be explained is the long term downward rigidity of nominal wages

dynamic price competition with network effects i consider a dynamic model of competition between two proprietary networks consumers die and are replaced with a constant hazard rate and firms compete for new consumers to join their network by offering network entry prices i derive a series of results pertaining to a existence and uniqueness of symmetric equilibria b monotonicity of the pricing function e g larger networks set higher prices c network size dynamics increasing dominance vs reversion to the mean and d firm value how it varies with network effects finally i apply my general framework to the study of termination charges in wireless telecommunications i consider various forms of regulation and examine their impact on firm profits and market share dynamics

a discussion of belgian unemployment combining traditional concepts and disequilibrium econometrics with a gdp of less than 100 billion and exports of more than 60 billion belgium comes perhaps closer than any other country to being a small open economy consequently trends in world trade and export performance have a major impact on domestic activity whereas the impact of domestic fiscal policy is damped by import leakages table 1 presents a few figures confirming these observations

two sided network effects a theory of information product design how can firms profitably give away free products this paper provides a novel answer and articulates trade offs in a space of information product design we introduce a formal model of two sided network externalities based in textbook economics a mix of katz and shapiro network effects price discrimination and product differentiation externality based complements however exploit a different mechanism than either tying or lock in even as they help to explain many recent strategies such as those of firms selling operating systems internet browsers games music and video the model presented here argues for three simple but useful results first even in the absence of competition a firm can rationally invest in a product it intends to give away into perpetuity second we identify distinct markets for content providers and end consumers and show that either can be a candidate for a free good third product coupling across markets can increase consumer welfare even as it increases firm profits the model also generates testable hypotheses on the size and direction of network effects while offering insights to regulators seeking to apply antitrust law to network markets

trading networks with price setting agents abstract in a wide range of markets individual buyers and sellers trade through intermediaries who determine prices via strategic considerations typically not all buyers and sellers have access to the same intermediaries and they trade at correspondingly different prices that reflect their relative amounts of power in the market we model this phenomenon using a game in which buyers sellers and traders engage in trade on a graph that represents the access each buyer and seller has to the traders we show that the resulting game always has a subgame perfect nash equilibrium and that all equilibria lead to an efficient allocation of goods finally we analyze trader profits in terms of the graph structure roughly a trader can command a positive profit if and only if it has an essential connection in the network thus providing a graph theoretic basis for quantifying the amount of competition among traders

accounting for unemployment a labour market perspective i examine whether prolonged high unemployment in canada can be attributed to various structural causes rather than to demand deficiency as found by macro econometric models the answer is largely negative neither the dispersion of sectoral growth rates nor excessive and rigid real wages can convincingly account for most unemployment contentions to the contrary are based upon inappropriately partial analyses enduring shifts in industrial structure have if anything been declining labour mobility is high much unemployment lasts too long to be frictional fuller quantitative understanding of the nature of unemployment can be achieved only in a more general framework

on the alternative explanations of persistence of unemployment in the oecd countries this paper begins with a summary statement of a few relevant facts about the worsening state of unemployment since the mid 1970s in the oecd countries a joint statistical test of the hypotheses of the natural rate hysteresis and the persistence is conducted by pooling annual data 1963 93 from up to 16 oecd countries the results provide strong evidence in support of the persistence hypothesis and the non linearity of the phillips curve while concurrently rejecting the other two alternative explanations

armod a small numerical macroeconomic world model with non clearing markets the purpose of this paper is to demonstrate the usefulness of a non walrasian numerical modeling approach to current macroeconomic problems of excessive unemployment and trade imbalances in the oecd area the model which consists of five world regions generates a sequence of short run equilibria the model captures international transmission mechanisms of business cycle impulses and of the effects of monetary and fiscal policy assuming flexible interest and exchange rates full capital mobility and adaptive expectations a scenario with successful international policy coordin ation illustrates how the model works copyright 1987 by the editors of the scandinavian journal of economics

capital accumulation and unemployment a tale of two continents in contrast to much recent work regarding the causes of european unemployment in this paper we emphasize the importance of capital accumulation but unlike the few previous studies which have examined the relationship between capital accumulation and unemployment we argue that what matters for the evolution of employment and the unemployment rate is not the absolute growth rate of a country s capital stock but its evolution relative to other countries capital stock the empirical validity of the above statement is demonstrated for almost all oecd countries using quarterly time series data for the period 1961 1995 more detailed evidence is also presented for germany japan and the united kingdom

network interconnection in telecommunications this paper discusses industries such as telecommunications where firms each have their own customers and must interconnect with other firms to provide a comprehensive service two scenarios are considered i the case of a symmetric unregulated industry and ii the case of an industry with a dominant regulated incumbent in the first provided there is sufficient product differentiation it is shown that firms agree to set interconnection charges above associated costs in order to obtain the joint profit maximising outcome in the second a formula for the welfare maximizing interconnection charge is derived relations with the efficient component pricing rule are discussed

network competition i overview and nondiscriminatory pricing we develop a model of unregulated competition between interconnected networks and analyze the mature and transition phases of the industry in this deregulated environ ment networks pay negotiated or regulated access charges to each other and com pete in prices for customers we show that a competitive equilibrium may fail to exist for large access charges or for large network substitutability and that freely negotiated access charges may prevent effective competition in the mature phase of the industry and erect barriers to entry in the transition toward competition last we examine the meaning and impact of policies such as the efficient component pricing rule

estimation of a quarterly macroeconomic model with quantity rationing we specify and estimate a small fix price model with quantity rationing on both the goods and labor markets the side of the market which is rationed is random the model is able to generate a productivity cycle and the degree of capacity utilization is endogenous the rationing scheme allocating supply between the various components of demand is estimated the probabilities of being in the various regimes the intensity of the dispquilibrium on the markets and the results of policy exercises are discussed

adoption externalities as public goods abstract a public good problem arises naturally in situations characterized by positive externalities or negative externalities for positive externalities agents furnish a public good by taking an action similarly for negative externalities agents furnish a public good by not taking an action we examine these externalities in a binary choice problem i e adoption externalities in each case there is a potential role for government intervention even when equilibrium transfers are not allowed since one equilibrium pareto dominates all others we analyze the positive and normative features of equilibria in these models and we explore the possibility of useful government intervention

rationalizability learning and equilibrium in games with strategic complementarities we study a rich class of noncooperative games that includes models of oligopoly competition macroeconomic coordination failures arms races bank runs technology adoption and diffusion r d competition pretrial bargaining coordination in teams and many others for all these games the sets of pure strategy nash equilibria correlated equilibria and rationalizable strategies have identical bounds also for a class of models of dynamic adaptive choice behavior that encompasses both best response dynamics and bayesian learning the players choices lie eventually within the same bounds these bounds are shown to vary monotonically with certain exogenous parameters we study the class of noncooperative supermodular games introduced by topkis 1979 and further analyzed by vives 1985 1989 who also pointed out the importance of these games in industrial economics supermodular games are games in which each player s strategy set is partially ordered the marginal returns to increasing one s strategy rise with increases in the competitors strategies so that the game exhibits strategic complementarity 2 and if a player s strategies are multidimensional marginal returns to any one com ponent of the player s strategy rise with increases in the other components this class turns out to encompass many of the most important economic applications of noncooperative game theory in macroeconomics diamond s 1982 search model and bryant s 1983 1984 rational expectations models can be represented as supermodular games in each of these models more activity by some members of the economy raises the returns to increased levels of activity by others in oligopoly theory some models of bertrand oligopoly with differentiated products qualify as supermodu lar games in these games when a firm s competitors raise their prices the marginal profitability of the firm s own price increase rises a similar structure is present in games of new technology adoption such as those of dybvig and spatt 1983 farrell and saloner 1986 and katz and shapiro 1986 when more users hook into a communication system or more manufacturers adopt an interface standard the marginal return to others of doing the same often rises similarly in some specifications of the bank runs model introduced by diamond and dybvig 1983 when more depositors withdraw their funds from a bank it is more worthwhile for other depositors to do the same in the warrant exercise

on endogenizing long run growth this assessment of recent theoretical work on endogenous growth identifies three different engines of long run growth i the asymptotic average product of capital is positive ii labor productivity increases as an external effect of capital accumulation iii there are feedback effects on the cost of accumulating knowledge or innovating a general model encompassing all three is considered and then used to review different proposed determinants of long run growth rates the contribution of endogenous growth theory has been to create a framework in which to explain why economic institutions and policies can have long run effects on growth rates

a macroeconomic rationing model of the belgian economy despite a wide recognition of the possible theoretical fruitfulness of the quantity rationing approach there prevails an equally wide suspicion as to the possibility of getting sensible econometric results out of this type of specification our aim in the following will be to show that sensible results can indeed be obtained we shall consider for that purpose the belgian goods and labor markets over the years 1953 1978 and specify the econometric model along the lines suggested in the previous chapter

european unemployment lessons from a multi country econometric study the paper summarizes the principal empirical findings of the european unemployment program it draws on 10 country studies which utilize the macroeconomic framework set out by sneessens and dreze 1986 the main conclusions are as follows i a major problem in europe is that productivity gains are quickly absorbed into wages and the effect of unemployment on wage settlements is generally weak ii a wage price productivity spiral means the european economies are inflation prone iii demand pressures spill over into the balance of payments rather than leading to price increases iv the major proximate determinant of employment in the 1 980s is the level of effective demand

profit sharing and employee share ownership profit sharing and employee share ownership saul estrin paul grout and sushil wadhwani this paper evaluates the likely effects of linking a part of a worker s pay to the employer s profits it has been suggested by weitzman that this would raise employment by lowering the cost of taking on an extra worker however this can only happen if existing workers are willing to let their share of value added fall and experience of those firms in the uk who already operate profit sharing schemes suggests that the weitzman mechanism is not operative there is however some evidence that profit related pay does boost productivity but there are other ways of raising productivity such as performance related pay which may be more effective productivity enhancing effects are likely to be greatest when employees are involved in decision making as well but this is likely to undermine the weitzman case still further even if the argument that profit sharing raises employment is not compelling it is sometimes suggested that it can do little harm however there is evidence that it may well be inflationary in which case the government would be advised to proceed cautiously we argue that there is very little case for the introduction of a permanent subsidy to encourage increased profit sharing although there may be a case for a temporary one to overcome managerial inertia however there is a danger that a subsidy will promote cosmetic schemes designed to be eligible for the subsidy but which do not reflect any real change in behaviour

effective demand and spillovers when individuals face rationing on a particular market they will seek to amend their trade offer on this and other markets to account for the extra constraint on their behaviour empirical researchers must attempt to mimic this behaviour by specifying effective demand functions there is no consensus however about how this should be done the development of applied multi market disequilibrium modelling has given this problem an immediate practical relevance moreover aggregation and computational considerations further complicate the problem of specifying theoretically consistent yet tractable effective demands this paper explores theoretical aspects of empirical effective demand functions and in this light reviews the existing empirical literature we stress the practical nature of the problems encountered in applied work and the limited guidance that theory provides the initial systematic discussion of the problems involved in specifying empirical effective demand functions in portes 1977 has been supplemented by gourieroux laffont and monfort 1980 ito 1980 sneessens 1981 and lee 1986 our paper is partly an update of this work there are three main candidates differing according to both the measurement of excess demand on other markets and how individuals are assumed to respond to this using linear forms for the effective demands portes showed how the three candidates are observationally equivalent in that they all imply the same level of trade perhaps because of this we find a wide range of effective demand concepts used in existing empirical applications we then consider the implications for empirical effective demand functions of allowing rationing to operate at a disaggregated level these smoothing by aggregation models have been the most significant