the pricing of durable exhaustible resources partial or total durability characterizes a large class of exhaustible resources hotelling s r percent rule will apply to a durable resource produced in a competitive market but will not apply if the resource is produced in a monopolistic market however the r percent rule does not mean that price is steadily rising it is shown that in general the competitive market price will fall initially as the stock in circulation increases and later will rise as the stock decreases and eventually depreciates toward zero after production ceases accounting for durability may thus help explain the u shaped long term price profiles observed for many resources 11 references 3 figures

the speed of the invisible hand abstract very little attention has been devoted to incorporating dynamic elements into empirical models of market structure and performance consequently there has been little progress in settling the issue of whether the market structure profits relationship is more than just a temporary phenomenon in this study an estimation equation is developed which allows for incomplete adjustment of past profits from expected future profits where expected profits depends on present and expected future changes in market structure the model is estimated pooling panel data across industries the findings indicate that adjustment to abnormal profits is relatively quick market share adjustments are non instantaneous and that inclusion of industry specific effects is important the results suggest that previous studies are susceptible to specification bias from omitted variables

rent control and prices of owner occupied housing we examine the relation between rent control and prices of owner occupied housing in th e presence of different qualities of housing while a rent ceiling and the price of condominiums are substitutes if housing is undifferentiated it is shown that this is not necessarily the case when housing differs in quality a complete dismantling of rent control may in fact increase the price of condominiums

noninformative trends in natural resource commodity prices u shaped price paths exonerated abstract m j mueller and d r gorin j environ econ manag 12 83 89 1985 claim that the u shaped price paths found in m e slade j environ econ manag 9 122 137 1982a result from a misspecification and disappear when the equation is properly specified to produce their result they rely on a radical shift in technology that is claimed to have occurred in 1920 there is however no evidence of a technology shift in that year instead a gradual adoption of new mining techniques beginning in 1904 is seen in addition to this misspecification they incorrectly locate other exogenous influences such as wars and recessions when corrections are made a radically different picture emerges with the new equation the u shaped price pattern persists and the only exogenous influence that is consistently insignificant is the technology shift

a quality adjusted price index for personal computers this study estimates quality adjusted price indexes for personal computers three separate hedonic models are estimated using data from 1 841 personal computers over the period 1984 1991 in addition to the traditional linear model a nonlinear model is developed and estimated the nonlinear model is parsimonious in parameters allows time varying attribute prices and can be estimated using a pooled data set the results indicate that nominal quality adjusted prices of mail order firms declined at an average annual rate of 24 62 quality adjusted prices of major manufacturers declined at a slower rate

the institutional causes of china s great famine 1959 1961 this paper studies the causes of china s great famine during which 16 5 to 45 million individuals perished in rural areas we document that average rural food retention during the famine was too high to generate a severe famine without rural inequality in food availability that there was significant variance in famine mortality rates across rural regions and that rural mortality rates were positively correlated with per capita food production a surprising pattern that is unique to the famine years we provide evidence that an inflexible and progressive government procurement policy where procurement could not adjust to contemporaneous production and larger shares of expected production were procured from more productive regions was necessary for generating this pattern and that this policy was a quantitatively important contributor to overall famine mortality

coal worldwide the international context of the british miners strike while attention has naturally focused on the domestic causes and consequences of the miners strike the international setting of the dispute has played a significant role in the origins and development of the crisis moreover the future prospects for the british coal industry cannot be evaluated without some understanding of the international context while it is certainly true that the operating losses of the ncb during the past few years have been inflated by the board s dubious accounting practices glyn 1984 it is also the case that pricing policy has played a crucial part in the industry s financial crisis wright 1984 central to this pricing policy which has rested on the principle of reducing the real price of coal has been the belief that cheap foreign coal is readily available to replace british output ncb 1984 p 5 consequently the ncb has been forced by fear of foreign competition to make contracts with the cegb which link the price of a part of the coal purchased by the cegb to the international price of coal for sale in antwerp rotterdam and amsterdam 1 it has been enough for some commen tators e g brittan 1984 merely to note the cheapness of foreign coal and condemn the inefficiency of british coal mining while failing to recognise the major crisis of over production which has arisen in the world coal market dramatically affecting the relation ship between prices and costs of production and delivery and creating conditions analogous to the dumping syndrome prevalent in the coal crisis of the 1920s and 1930s neumann 1934 pp 30 31 the first part of our paper will therefore examine the origins and development of the recent crisis in the world coal market in describing the market s main characteristics we shall pay particular attention to the role of the oil com panies whose growing involvement in the coal business has so far received only limited attention kennedy 1978 tanzer 1980 wright and rutledge 1985 oil company mining projects are now integrating wholly new coal mining areas into the world market we conclude this section by examining one such project at el cerrejon in northern colombia where exxon is developing what will probably become the biggest coal mine in the world

efficiency market power and profitability in american manufacturing reply a significant positive association between concentration and profitability is perhaps the most widely reported statistical relationship to be found in the literature of industrial organization 25 according to conventional oligopoly theory this reflects the ability of the leading firms in concentrated markets to collude tacitly or explicitly some economists most notably harold demsetz 8 9 have challenged the conventional view demsetz argues that it is the superior efficiency of large firms which results in both high concentration and high profits he supports this argument with evidence replicated by round 20 and carter 4 that concentration increases the profits of large firms but not small firms if the firms in an industry are equally efficient effective collusion should raise the profits of small and large firms alike the fact that it doesn t strongly suggests that efficiency concentration and profits are interrelated in american manufacturing there are two bits of evidence which indicate the large firm efficiency and collusive behavior coexist in much of american manufacturing the first is the profitability studies of imel and helmberger 11 gale 10 and shepherd 21 these studies suggest that considered together market share and concentration are both significantly positively related to profitability if as argued by mcgee 15 and weiss 25 market share is capturing the effect of lower costs and or superior products concentration must be capturing the effect of collusive behavior the second is carter s 4 refinement of demsetz s methodology carter regressed price cost margins on concentration capital intensity and advertising intensity for large and small firms separately he reports a positive concentration coefficient for large firms which is greater than that for small firms and which is significantly associated with large firm profitability the difference in the estimated coefficients may be taken as evidence of large firm efficiency and the significance of the large firm coefficient as evidence of collusive behavior whether the concentration profits relationship derives largely from efficiency as demsetz believes or largely from collusive behavior as the conventional view would have it is a more difficult empirical question the answer has important implications for merger policies remedies pertaining to tacitly collusive oligopolies and legislative proposals

centralized pricing versus delegating pricing to the salesforce under information asymmetry the issue of delegating pricing responsibility to the salesforce is of interest to marketing academics and practitioners it has been shown by lal 1986 that under certain situations with information asymmetry it is more profitable for the firm to delegate pricing authority to the salesforce than to have centralized pricing in this paper we re examine situations where information asymmetry exists and analyze its effect on the decision of the firm to set a price or delegate pricing responsibility to the salesforce using contract theory we find that when the salesperson s private information can be revealed to the firm through contracting centralized pricing performs at least as well as price delegation we derive the optimal centralized pricing contract under a set of standard assumptions used in the economics and business literature

interpreting econometric evidence the behaviour of consumers expenditure in the uk abstract the dynamic models of consumers expenditure proposed by davidson et al 1978 and hendry and von ungern sternberg 1979 are re appraised in the light of hall s 1978 analysis of the empirical implications of the life cycle permanent income hypothesis in particular that the series for consumption should obey a random walk apart from trend in an attempt to reconcile the conflicting findings monte carlo experiments are used to demonstrate that if the davidson et al model were actually correct the hall model would appear to give a good description of the data and would probably not be rejected all the models are re estimated with new data for the uk and these data do reject a modified random walk specification in conclusion we discuss the issue of income exogeneity and comment on questions of model selection and interpretation

firm and industry effects in industrial economics the traditional view in industrial economics suggests that high concentration leads to tacit collusion poor performance and elevated profit followers of the traditional view relied upon the empirical relationship between profit rates and market concentration to justify the highly activist antitrust policy of the 1945 1980 period the activist antitrust era reached its zenith with the nearly per se prohibition of horizontal mergers as outlined in the 1968 merger guidelines issued by the justice department s antitrust division the 1980s have witnessed the emergence of the revisionist school as the dominant view in the field of industrial economics the revisionists contend

preference revelation and monopsony abstract 1 johnson demonstrated the formal equivalence between the free rider problem and monopsony 2 vickrey s method for eliminating the inefficiencies resulting from monopsony monopoly works by converting simple monopsonists monopolists into perfectly discriminating monopsonists monopolists 3 we show that three recently proposed solutions to the free rider problem have the same rationale i e they use clarke taxes to convert johnson s simple monopsonists into perfectly discriminating monopsonists the three mechanisms are those of i clarke and groves ii groves and ledyard and iii arrow the relationships between these mechanisms and between each of them and monopsony are analyzed diagrammatically

regulating a monopolist with unknown demand and cost functions we consider the design of regulatory policy when the regulator is imperfectly informed about both the firm s cost function and the demand function it faces to some extent the optimal policy here is the natural combination of the optimal policies when there is uncertainty only about either demand or cost important qualitative differences also exist however for example it may be optimal to set prices below marginal cost and the pricing authority delegated to the firm may be more limited when there is uncertainty about both cost and demand

innovation and industry evolution the theoretical literature on innovation has been concerned with a single innovation produced by a number of identical agents by contrast we consider a market in which one firm is the current incumbent while the remaining firms are challengers moreover we consider a sequence of innovations so that success does not imply that the successful firm reaps monopoly profits forever after but only until the next better innovation is developed we begin with a fully optimizing behavioral model and derive the equivalent of the schumpeterian process of creative destruction that is a firm enjoys temporary monopoly power but is soon overthrown by a more inventive challenger the essential point to grasp is that in dealing with capitalism we are dealing with an evolutionary process the fundamental impulse that sets and keeps the capitalist engine in motion comes from the new consumers goods the new methods of production or transportation the new markets the new forms of industrial organization that capitalist enterprise creates schumpeter 1942 pp 82 83

the impact of rent control on rents in the free sector in most cases rent control covers only a part of the housing stock this note provides a simple analysis of the impact which rent control and non price rationing exert on the rent in the free sector it is shown that depending on the rationing mechanism rents in the free sector can be higher or lower than in the absence of rent controls

emergence of entrepreneurs following exogenous technological change this paper explains how after an exogenous technological change occurs entrepreneurs displace incumbents who were ex ante capable of exploiting any innovations that resulted from the change the model initially considers classical economic assumptions in the context of process innovations and then its robustness to uncertainty bounded rationality firm asymmetry and product innovations are discussed the model is preliminarily tested against industry trends using both results from an analysis of the information technology sector and from the literature the paper does not suffer from the inconsistency of explaining how capable incumbents are displaced by resorting to characterizations of incumbents as incapable due to some inefficiency the paper models incumbents as efficient yet rationally choosing in some instances to be displaced copyright 1999 john wiley sons ltd

world coal and uk energy policy a company level perspective abstract as a contribution to the debate about the future of the uk coal industry this paper provides an overview of the corporate structure of the world coal industry detailing company diversification ownership transnationality concentration of production and profitability its main argument which has a strong bearing on coal import policy is that whereas the world coal industry and international trade currently exhibit all the signs of overproduction hypercompetition and declining profitability there is no reason to assume that this is a stable scenario the company structure of the export sector variously indicates a potential for supply disruption cost escalation and informal collusion all of which have implications for the future level of prices particularly as the market tightens once so called marginal producers like the uk are knocked out of the market

the nature of opec and oil price changes abstract recent models of the oil market have continued to employ dominant firm monopoly type assumptions regarding opec behaviour other recent studies have highlighted the importance of the internal behaviour of opec the paper attempts to provide a framework within which these approaches are compatible and which provides a significant role for investment needs as a key variable in determining price changes

profit entry and changes in concentration abstract the simultaneity between profit entry and changes in concentration is examined the sample includes 481 observations on 4 digit industries over the years 1972 1977 and 1977 1982 results show that profits respond positively to entry barriers and initial concentration net entry responds positively to initial profits and responds negatively to entry barriers concentration moves toward its steady state level but the rate of adjustment is very slow the competitive process left on its own does not seem to move quickly toward equilibrium

cournot competition and green innovation an inverted u relationship we examine the relationship between competition and innovation in an industry where production is polluting and r d aims to reduce emissions green innovation we present an n firm oligopoly where firms compete in quantities and decide their investment in green r d when environmental taxation is exogenous aggregate r d investment always increases with the number of firms in the industry next we analyse the case where the emission tax is set endogenously by a regulator committed or time consistent with the aim to maximise social welfare we show that an inverted u relationship exists between aggregate r d and industry size under reasonable conditions and is driven by the presence of r d spillovers

small firms in economic theory this is the fourth of a series of critical survey articles the aim of the series is to report on recent developments to provide an assessment of alternative approaches and to suggest lines of future inquiry it is intended that the articles will be accessible not only to other academic researchers but also to students and others more practically involved in the economy future survey articles will include warren samuels on institutional economics and philip arestis on post keynesian

the world coal trade a commentary abstract the paper gives an account of the recent history of the world coal trade and discusses the forces which bear upon current and prospective production and prices issues relating to depletion of the coal resource and global environmental impact are also discussed

gas market prospects and relationship with oil prices abstract this paper explains how the international natural gas market is vulnerable because of several specific features and how it will be saturated at least until the year 1990 the share of the gas rent is seen to be the main stake in the negotiations between sellers and buyers the purpose of this paper is to present some elements enabling an understanding of the logic of gas pricing net back method versus parity approach the paper also analyses to what extent the future price of gas will be disconnected from that of crude oil in the same way as coal

estimating distributed lags in short panels with an application to the specification of depreciation patterns and capital stock constructs this paper considers the problem of estimating distributed lags in short panels though the n time series contained in a panel may allow for relatively precise estimates of identified lag coefficients identification requires restrictions on the contribution of the unobserved pre sample x s to the current values of y and the shortness of panels focuses attention on this matter we investigate two such restrictions the first constrains the relationship between the presample and insample x s while the second constrains the lag distribution itself an example which investigates empirically how to construct capital stocks for the analysis of rates of return closes the paper

concepts and measures of natural resource scarcity with a summary of recent trends a general model of resource scarcity is presented from which previous models can be derived as special cases previous models of scarcity are compared and contrasted refining the concept of scarcity and leading to a resolution of current disputes over the appropriate measure of scarcity an update of the original work done by barnett and morse is summarized leading to reconsideration of their original conclusions it is found that energy and forest products experienced increasing scarcity during the 1970s

the role of small firms in the industrial development and transformation of czechoslovakia this article presents an analysis of the role of small firms in the formation and reform of the czechoslovak manufacturing sector it attempts to give an understanding of the industrial structure formed under the past regime within the framework of the mass production paradigm as manufacturing productivity gradually declined over the past 25 years and small firms have been virtually eliminated systemic preference has been given to the development of large monopolies consequently a monolithic coalition structure of enterprise managers state bureaucrats and political nomenklatura has arisen and continues to present itself as a serious hindrance to economic transformation while small firms have the potential to play a critical role in the democratic marketization of czechoslovakia current government preoccupation with the rapid privatization of the state sector risks damaging the development of a balanced distribution of firm size and in turn the revitalization of the society

the determination of oil prices 1945 1995 the paper provides a theoretical framework to explain the determination of international oil prices based upon the interaction of supply and demand curves the analysis of components of the framework identifies important characteristics of the global market for crude oil the paper applies the framework to the oil market from 1945 in particular it incorporates key changes in the market to enhance understanding of how the market has been and is working finally the framework is used to explain why oil prices have become more volatile and what issues and questions arise from current oil market behaviour

innovation and the evolution of market structure this paper examines the association between innovation and the evolution of market structure a dynamic model of market concentration is applied to seventy three u k industries 1970 79 and the results are found to be consistent with the hypothesis that innovation is deconcentrating the results reported here and those contained in earlier work combine to suggest that innovation and changes in market concentration interact in a relatively rapid mutually reinforcing but rather weak spiral of increased innovation and decreasing concentration copyright 1990 by blackwell publishing ltd

the dynamics of market structure abstract in this paper changes in market concentration are modelled in terms of long run steady state levels and the adjustment towards them both the speed of adjustment and the long run levels of concentration are allowed to vary across industries non linear three stage least squares estimates for allowing for the endogeneity of profits and advertising for 184 u s industries 1963 1967 suggest that both the speed of adjustment and the levels of concentration in the long run are largely determined by minimum efficient scale

the changing structure of the international oil industry implications for opec this paper examines the changes in international oil market structure observed in the 1980s and early 1990s and assesses possible effects on oil market conditions in the future and implications for opec it focuses on the trend toward a more vertical organization mainly resulting from substantial purchases of downstream assets by state owned oil companies in major oil producing countries while the gulf war prevented greater horizontal concentration of oil reserves it merely interrupted the trend toward vertical concentration in the international oil industry the vertical integration of only some of the opec members will cause a further divergence of goals within the organization resulting in a lower likelihood of opec regaining its former position as an effective cartel if the trend toward greater vertical concentration increases future oil prices will in part be affected by decisions made by vertically integrated firms

models of resource markets and the explanation of resource price behaviour abstract much of the recent theoretical work in resource economics has been aimed at relaxing the stringent simplifying assumptions of the basic hotelling model in an attempt to better explain observed resource price behaviour this paper surveys the characteristics of exhaustible resource markets that are likely to be important for the development of successful positive models in particular we discuss exploration and its relationship to production and market price the effects of various forms of uncertainty on price behaviour and for some resources the treatment of durability finally we address the question of whether producer behaviour can properly be viewed as that of dynamic optimization this paper should be seen as an attempt to stimulate discussion over research directions and priorities in resource economics

prices vs quantities and delegating price authority to a monopolist this paper examines the desirability of allowing a monopolist to determine the market price we find that none of the regulatory mechanisms previously discussed in the prices vs quantities literature strictly dominates unregulated monopoly price setting furthermore despite suggestions by others price setting by a regulated monopolist whose profits coincide with society s net benefits is not always the most desirable means of control quantity setting by such a monopolist may instead be the preferred choice combining both into one incentive compatible mechanism provides the best regulatory scheme and one in which the regulator need not be informed about costs

rent control and housing maintenance controls on the conditions of renting housing can take many different forms with different consequences for the market this paper contains analyses of the effects of different regulatory forms on in particular the maintenance decision we review and extend previous approaches and find that not all of the familiar predictions of the basic neoclassical model can be generated by a more sophisticated model others have extended the basic model focusing on the maintenance aspect but we cannot agree entirely with their conclusions a careful specification of the relationship between costs and quality is necessary to derive useful predictions about the effects of rent and eviction controls

the development and use of machine tools in historical perspective abstract improvements and diffusion of machine tools have had a major impact on productivity in manufacturing industry since the industrial revolution the impact has been both direct and indirect the direct impact consists of rising labor productivity through the use of faster more accurate more mechanized machines and of the higher capital productivity through higher operating rates greater reliability and higher utilization rates the indirect impact arises as the use of new or improved machine tools has necessitated or facilitated organizational changes affecting both labor capital raw materials and energy the magnitude of these impacts has varied over the years with the areas of application as new production methods have made possible entirely new products or lowered the cost of existing products sufficiently to create new markets the first part of the paper contains a review of the historical development of machine tool technology since the industrial revolution paying particular attention to the role of interaction between producers and users of machine tools the second part focuses on the way in which recent development differs from that in earlier periods in particular it is found that the major changes in machine tool technology from the so called american system of manufactures in the early 19th century to the development of detroit automation in the 1950s have tended to improve mass production methods by contrast the development of numerical control beginning in 1948 has opened up the possibility of extending industrial production methods and automation to areas previously characterized more by handicraft methods even though this technology is not yet fully utilized it is clear that the economics of industrial production has been revolutionized by the cost reduction of small scale production relative to large scale and the degree of flexibility offered by the technology the third section of the paper deals with the present development trends particularly discussing the increasing importance of flexibility and the shifting emphasis from development of individual pieces of machinery to integration and control of entire manufacturing processes i a through the use of industrial robots the reasons for the need for greater flexibility in manufacturing are also identified

currents and sub currents in innovation flows explaining innovativeness using new product announcements the creation of new knowledge is a haphazard process not every sector in an economy is equally involved the effect of industry structure on innovativeness has been a focus of attention for a long time by both academics and policymakers in a much quoted article using unique data new product announcements acs and audretsch acs z j audretsch d b 1988 innovation in large and small firms an empirical analysis american economic review 78 4 678 690 identified several characteristics of industry structure and their effects on innovativeness by analyzing a new and more consciously compiled database we re examine their original claims our results largely support their findings industry concentration and degree of unionization for instance hamper innovation skilled labor promotes it our findings diverge in one significant respect from theirs we suggest that the large firms do not contribute more to an industry s innovativeness than small firms at the industry level we find strong support for the schumpeter mark i perspective of creative destruction by small firms rather than creative accumulation by large firms in addition we show that less dedicated innovators prove more susceptible to firm external industry factors than more committed innovators an unfavorable competitive environment decreases the likelihood that less successful innovators will announce new products c 2008 elsevier b v all rights reserved

the impact of oil company investment on the world coal industry overcapacity and price destabilization 1973 1992 this paper investigates the impact of oil company investments on the world coal industry since the first oil price shock of 1973 it details the scope of these investments both in the usa and elsewhere and demonstrates how they have served to destabilize and depress international coal prices in particular it establishes a novel and robust link between oil company investment in us coal which is sold on the domestic market and the behaviour of us coal export prices

fossil fuels stock externalities and backstop technology the hotelling exhaustible resource model is extended to include stock pollution and nonpolluting backstop technology it is shown that an optimal energy consumption strategy typically includes a regime in which the two energy sources are consumed simultaneously along this regime fossil fuel consumption decreases and backstop consumption increases together fossil fuel and backstop consumption may form eleven optimal regime combinations a decrease in the backstop price decreases the initial level of optimal emission tax

on delegating price authority to a regulated firm this article models a regulatory environment in which the regulated firm possesses better information about demand conditions than does the regulator the regulator would like to tie prices to the firm s private information in a socially optimal way to do so the regulator must induce the firm either truthfully to reveal private information or equivalently unilaterally to set socially optimal prices this is accomplished by assessing lump sum subsidies or taxes that depend in an appropriate way on the prices announced by the firm this mechanism can be reinterpreted as a two part tariff scheme whereby both the service fee and price per unit respond to shifting demand conditions

a new methodology linking concentration dynamics to current and steady state profits examining korean industrial policy during take off abstract we model the dynamics of industrial structure and market power using korean manufacturing data during the take off period 1978 82 structure conduct performance scp methodologies have been criticized for using accounting data and because a few superior firms may have greater shares and greater profits both are argued to present possible spurious correlations between concentration and profits this paper follows earlier work which shows that market structure responds to observed accounting profits as if these were accurate indices of real profits and not as if leading firms are perceived to have unmatchable advantages the methodological contribution of this model is a new latent variable for steady state profits derived from the speed of structural adjustment long run profits are identified by the hypothesis that structural adjustment will be more rapid when industries are farther from steady state levels we analyze the long run profits latent variable finding strong support for this hypothesis the speed of adjustment is greater for positive and negative deviations from steady state structure we show that the profits and structural adjustment relationship is non monotone the scp criticisms above are based on spurious correlations which are monotone in profits and structure positing spurious correlations which are at the same time monotone in structure and non monotone in structural adjustment seems less plausible than accepting the scp results which are consistent with both our analysis also is new in that it is the first direct econometric analysis of korean industrial policy during its take off years we note that in korea unlike elsewhere industrial policy was hypothesized to lead to concentration and market power in the popular press and by professional economists ours is the first direct econometric analysis of this hypothesis and we find it supported

rent control its rationale and effects this paper discusses the rationale behind rent control and analyses its effects using a capital theory framework in combination with traditional bid rent analysis the experience in hong kong and o

a test of the hotelling valuation principle time series tests of the hotelling r percent rule for natural resource prices have not been strongly supportive but the tests and the data are subject to serious difficulties we propose here an alternative testing strategy based on another but less widely known implication of the hotelling model we test this implication which we call the hotelling valuation principle by regressing the market values of the reserves of a sample of u s domestic oiland gas producing companies on their estimated hotelling values we find that the estimated hotelling values account for a significant portion of the observed variations in market values and that the hotelling measures are better indicators of the market values of petroleum properties than two widely cited publicly available alternative appraisals

hartwick s rule in open economies to sustain constant consumption the hartwick rule prescribes reinvesting all resource rents in reproducible capital this paper shows that the rule does not apply to open economies since the underlying stationary technology assumption is violated when gains from trade are taken into account a correct analog to the hartwick rule for open economies is developed and applied to a model of capital accumulation and resource depletion la regle de hartwick dans les e conomies ouvertes pour maintenir la consommation constante la regle de hartwick prescrit qu il faut reinvestir toutes les rentes des ressources dans du capital reproductible ce me moire montre que la regle ne s applique pas dans le cas d economies ouvertes parce que le postulat d une technologie stationnaire n9est pas satisfait quand on tient compte des gains engendres par le commerce international l auteur developpe une version correcte pour les economies ouvertes dans 1 esprit de la regle de hartwick et l applique a un modele d accumulation de capital et d epuisement des ressources

economic implications of 3d printing market structure models in light of additive manufacturing revisited abstract additive manufacturing am colloquially known as 3d printing is currently being promoted as the spark of a new industrial revolution the technology allows one to make customized products without incurring any cost penalties in manufacturing as neither tools nor molds are required moreover am enables the production of complex and integrated functional designs in a one step process thereby also potentially reducing the need for assembly work in this article we discuss the impact of am technology at both firm and industry level our intention is to discern how market structures will be affected from an operations management perspective based on an analysis of established economic models we first identify the economic and technological characteristics of am and distill four key principles relevant to manufacturers at firm level we then critically assess the effects of am at industry level by analyzing the validity of earlier assumptions in the models when these four principles apply in so doing we derive a set of seven propositions which provide impetus for future research in particular we propose that in a monopoly the adoption of am allows a firm to increase profits by capturing consumer surplus when flexibly producing customized products meanwhile in competitive markets competition is spurred as am may lower barriers to market entry and offers the ability to serve multiple markets at once this should ultimately result in lower prices for consumers

an appropriate mechanism of fuels pricing for sustainable development abstract in this work the authors after a brief outlook concerning the markets of main energy commodities propose an alternative mechanism for fuel pricing consisted with a sustainable development technological change and technological pluralism costs and environmental issues are the benchmarks of the discussion developed the two mechanisms here proposed for fuel pricing try to encompass all these aspects stressing the scarcity concern not only under a merely based resource point of view but emphasizing also the technological variable as the first one to take into consideration in fact technology the mean by which resources are transformed into usable services energy forms is strictly linked to its limits above all productivity efficiency and environmental effects and cannot be any more considered only following the classical principles of the lowest cost of utilization without evaluating the other aspects related to the goals of sustainable development widely shared at the international level furthermore taking into consideration that some estimates of petroleum life expectancy calculate about 40 50 yr of consumption at current rates of demand a new mechanism to consider the right value of this resource and consequently all energy commodities is necessary without any pretension of exhaustion of the topic this work seems to be in line with this perspective trying to apply all these principles to price fuels

regulating a monopolist with unknown costs we consider the problem of how to regulate a monopolistic firm whose costs are unknown to the regulator the regulator s objective is to maximize a linear social welfare function of the consumers surplus and the firm s profit in the optimal regulatory policy prices and subsidies are designed as functions of the firm s cost report so that expected social welfare is maximized subject to the constraints that the firm has nonnegative profit and has no incentive to misrepresent its costs we explicitly derive the optimal policy and analyze its properties in their classic papers dupuit 2 and hotelling 5 considered pricing policies for a bridge that had a fixed cost of construction and zero marginal cost they demonstrated that the pricing policy that maximizes consumer well being is to set price equal to marginal cost and to provide a subsidy to the supplier equal to the fixed cost so that a firm would be willing to provide the bridge this first best solution is based on a number of informational assumptions first the demand function is assumed to be known to both the regulator and to the firm while the assumption of complete information may be too strong the assumption that information about demand is as available to the regulator as it is to the firm does not seem unnatural a second informational assumption is that the regulator has complete information about the cost of the firm or at least has the same information about cost as does the firm this assumption is unlikely to be met in reality since the firm would be expected to have better information about costs than would the regulator as weitzman has stated an essential feature of the regulatory environment i am trying to describe is uncertainty about the exact specification of each firm s cost function in most cases even the managers and engineers most closely associated with production will be unable to precisely specify beforehand the cheapest way to generate various hypothetical output levels because they are yet removed from the production process the regulators are likely to be vaguer still about a firm s cost function 12 p 684 as this observation suggests it is natural to expect that a firm would have better information regarding its costs than would a regulator the purpose of this paper is to develop an optimal regulatory policy for the case in which the regulator does not know the costs of the firm one strategy that a regulator could use in the absence of full information about costs is to give the firm the title to the total social surplus and to delegate the pricing decision to the firm in pursuing its own interests which would then be to maximize the total social surplus the firm would adopt the same marginal cost pricing strategy that the regulator would have imposed if the regulator had

on measuring natural resource scarcity conclusions concerning trends in natural resource scarcity may depend critically on the choice of scarcity index unfortunately the prevalence of vertical integration in natural resource industries has hindered the use of some otherwise desirable scarcity measures in this paper duality theory is used to derive an econometric procedure for estimating one such measure the shadow price of the resource in situ empirical results for the canadian metal mining industry indicate that resource scarcity as measured by this shadow price has decreased substantially over time