effluent regulation and long run optimality a regulator faced with free entry of firms is concerned not only with the implications of public policy for the discharges from a representative firm but also with the total pollution observed at the long run market equilibrium the regulator must take into account not only the effects of regulations upon the net marginal returns of the firm but must also consider the total profit of the firm and incentives for entry and exit this paper shows that effluent charges and tradeable effluent permits lead to long run optimality with entry of small firms the difference between firm payments and environmental damages is interpreted as the rent accruing to the environmental resource this result applies only to the competitive case with small polluters the analysis presented here allows a comparison and clarification of the literature on small and large polluters in a multi input framework with social damages dependent upon total effluents effluent charges are shown here to result in socially optimal entry confirming an assertion of baumol and oates 2 p 179 fn 161 and the important result of schulze and d arge 15 by taking average as well as marginal damages into account the effluent charge results in optimal firm scale levels and the correct input mix at the free entry market equilibrium the firm subject to an effluent tax will operate above or below the private minimum efficient scale depending upon whether average external costs exceed or are less than marginal external costs since public policy to reduce effluents is often directed at reducing the effluentgenerating activity some policy recommendations include a tax on the final output of the polluting firm in some theoretical analyses a relation between the output of the firm and the effluent level is identified and a pigouvian output tax is applied this approach should not be followed by policymakers since an output tax does not provide firms with the correct incentives for either input substitution or market entry it is shown that while a lump sum transfer is needed to provide correct entry incentives when a pigouvian output tax is applied no such transfer is needed if the tax is correctly applied to effluents contrary to 5 even if optimal firm scale and i thank the referees for helpful suggestions the support of the national science foundation under grant ses 82 19121 is gratefully acknowledged any errors are my responsibility 103

the dynamic behavior of wages and prices cointegration tests within a large macroeconomic system the dynamic relationship between wages and prices has long held a central place within the economic literature most macroeconomic models make assumptions as to the causal relationship between the two variables unfortunately empirical investigations have produced widely divergent results in particular the present paper examines the results of time series studies and argues that the lack of a consensus is due to improperly specified models once the wage price relationship is embedded within a multiple vector system identification of a wage price cointegrating relationship is significantly improved in addition the increased efficiency yields evidence in favor of the dual feedback between wages and prices

does the energy efficiency paradox exist technological progress and uncertainty we explain why firms may choose not to undertake investments inenergy saving technologies that appear profitable from a net presentvalue perspective as future technological advances are inherentlyuncertain and investments in new technology are at least partly irreversible it may pay to postpone investments in energy savingand wait for the arrival of improved varieties this insight casts doubton the existence of so called low hanging fruits in energy saving although we do not wish to deny that organisational failures may alsobe important failure to appreciate the underlying stochasticity oftechnological progress may obscure the insight that there is value inwaiting and costs involved in terminating the option to invest theappetite for low hanging fruits will be less when these costs areincorporated in the analysis we demonstrate that the effect of thearrival rate of new technologies on the adoption lag for a rational firmis ambiguous the same holds for the effect of the expected jump inefficiency of new technologies government policies aimed at enhancingthe adoption of new technologies through stimulation of r d maytherefore be counterproductive

history friendly models of industry evolution the computer industry the model presented in this paper is the first of a new generation of evolutionary economic models history friendly models history friendly models are formal models that aim to capture in stylized form qualitative and appreciative theories about the mechanisms and factors affecting industry evolution technological advance and institutional change put forth by empirical scholars of industrial economics technological change business organization and strategy and other social scientists in this paper we have analyzed the long term evolution of the computer industry in particular we have examined the emergence of a dominant firm in mainframes the introduction of a major innovation microprocessor the opening up of a new market segment personal computers ad the competition there between newcomers and diversified old established firms we have taken a body of verbal appreciative theorizing developed a formal representation of that theory and found that the formal version of that theory is consistent and capable of generating the stylized facts the appreciative theory purports to explain going through this analytic exercise has significantly sharpened our theoretical understanding of the key factors behind salient aspects of the evolution of the computer industry copyright 1999 by oxford university press

firm incentives to promote technological change in pollution control reply abstract the process of technological change in pollution control is broken into three basic steps innovation diffusion and optimal agency response firm incentives to promote these steps are then examined under five regulatory regimes direct controls emission subsidies emission taxes free marketable permits and auctioned marketable permits on a relative basis emission taxes and auctioned permits provide the highest firm incentives to promote technological change at times free permits generate lower incentives direct controls which are common regulatory tools usually provide the lowest relative firm incentives to promote technological change

pollution taxes when firms choose technologies we consider the properties of a pollution tax when the regulated firm has a discrete choice of technologies with which to reduce pollution the firm s technology choice makes possible two sequences of play the traditional one in which the regulator moves first committing to a tax rate before the firm adopts a technology and an alternative one in which the firm moves first by adopting a technology we find that a range of pollution levels including possibly the first best one are unattainable when the regulator moves first the regulator may be better able to achieve the first best outcome when the firm moves first

the demand for nominal and real money balances in a large macroeconomic system cointegration has become a popular empirical technique used to estimate the existence and stability of money demand relationships a common approach has been to estimate a single equation system with real money balances ml real income and an interest rate although hafer and jansen 13 friedman and kuttner 10 and stock and watson 29 find only minimal support for this specification baba hendry and starr 6 estimate a more complicated ml relation by including specific opportunity cost variables and find stronger support for the ml relation using post wwii data there have been four reasons put forth to explain the lack of a cointegrating relation between ml real income and the interest rate stock and watson 29 conclude that a stable money demand relation exists in data from 1900 89 but not for the post war period alone their explanation is that sufficient variation exists in the longer sample to identify money demand but excessive multicollinearity among variables during the post war period prevents unique identification baba hendry and starr 6 bhs maintain that misspecification of the ml relation is the reason for poor results they augment the money demand function with inflation a measure of long term bond yield and risk and learning curve weighted yields on newly introduced ml and m2 assets bhs claim their specification is able to account for the missing money period of 1975 76 the velocity decline of 1982 83 and the ml explosion of 1985 86 while standard ml models cannot friedman and kuttner 10 offer a third reason why the simple money demand equation fails they estimate a single equation model for several periods and conclude that a money demand vector exists over the 1960 2 79 4 period for ml however when data is included

on real and sticky price theories of the business cycle after presenting some facts about the growth of government in western industrialized countries possible causes of this development are analyzed from a public choice perspective next some empirically tested theories which seek to explain this growth are discussed finally possible consequences for efficiency and individual liberty are examined it is shown that both the number and size of interest groups age of democracy as stated by mancur olson 1982 and the increasing share of government expenditure in gdp seem to exert a negative influence on the growth rate of gdp copyright 1986 by ohio state university press

pollution permits and environmental innovation abstract this paper starts with a warning about the negative impact of plain pollution allowance markets on environmental pollution innovation stand alone spot markets enable the government to expropriate an innovation by offering a competing technology pollution permits that puts an arbitrary downward pressure on the licensing price advance allowances reduce expropriation but still create suboptimal incentives for innovation they have the further drawback that permits are inefficiently used when the innovation occurs options to pollute at a given striking price fare better than allowances because they create private incentives to phase out pollution in the case of innovation we characterize the social optimum and show that it can be implemented by issuing options to pollute inter alia finally the paper compares ex ante and ex post government procurement surprisingly ex post licensing by the innovator to the government may yield a higher licensing fee than an ex ante contract

real wages over the business cycle evidence from panel data one topic on which keynes did not disagree with classical economists was the cyclical behavior of real wages keynes 1936 as well as various classical writers predicted that real wages should move countercyclically quoting the general theory p 17 in general an increase in employment can only occur through the accompaniment of a decline in real wages thus i am not disputing this vital fact which the classical economists have rightly asserted as indefeasible this prediction is based on the premise of competition and a given short run capital stock increases in employment then correspond to more intensive use of capital and through diminishing product lower real wages for this reason evidence by dunlop 1938 and tarshis 1939 that real wages move procyclically was viewed as paradoxical both dunlop and tarshis based their findings on an observed positive correlation between real and money wages which given the procyclical movement of money wages implies a positive correlation between

wage growth and the inflationary process a reexamination the nature of the relationship between wage growth and inflation has long been the subject of ongoing debate the expectations augmented phillips curve theory contends that the two variables are mutually causal however the original wage type phillips curve model argues it is inflation that causes wage growth rather than vice versa the price markup scheme holds an opposite view and asserts that wage growth plays an independent causal role in the inflationary process of course other theories e g the monetarist deny the presence of any reliable linkage between wages and prices researchers have also expended enormous effort attempting to investigate empirically the relationship between wage growth and inflation but with mixed results for example mehra 24 and ashenfelter and card 1 report results suggesting a bidirectional causality barth and bennett 2 and stein 37 38 find causality running from prices to wages without feedback while shannon and wallace 34 and hill and robinson 19 report results showing causality only in the reverse direction from wages to prices still gordon 11 bazdarich 4 batten 3 and mehra 27 find no causal linkage between the two variables clearly such remarkably mixed evidence is unfortunate in light of the profound implications that the precise wage price relationship may have for economic and public policy a more recent and quite interesting study is that of mehra 28 mehra employed the technique of cointegration and error correction modelling on u s quarterly data for the period 1959 1 1989 3 he concluded that inflation and wage growth are cointegrated implying that their long run movements are correlated as the expectations augmented phillips curve theory predicts however contrary to this theory and in accordance with the original wage type phillips curve view mehra argued that the inflation wage growth long run correlation is primarily the outcome of the former causing the latter mehra s model encompasses three basic variables namely prices p productivity adjusted wages w and an output gap proxy g he tested each of the three variables in logs for the presence of unit roots finding evidence of two unit roots in p and w but a single unit root in g mehra then examined cointegration of the two variables having two unit roots p w his re

environmental innovation and environmental performance abstract by estimating a simultaneous panel data model of environmental innovation and toxic air pollution this paper identifies bi directional causal links between the two we study a panel of 127 manufacturing industries over the period 1989 2004 pollutant emissions are an implicit measure of policy stringency and environmental patent counts are used to measure environmental innovation after accounting for the joint endogeneity we find that environmental innovation is an important driver of reductions in us toxic emissions conversely we find that tightened pollution targets induce environmental innovation however our estimates indicate that the environmental policy multiplier the proportionate contribution of induced innovation to long run emission reduction is small

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

estimating the gender wage gap in rawalpindi city studies estimating wage discrimination against women have rarely been conducted for third world countries and no research has been directed to this issue in pakistan at all this article uses data from rawalpindi city to calculate the magnitude of the male female earnings gap and identifies the proportion of this gap which results from discrimination as well as that which stems from differences between males and females in productivity characteristics in addition to the oaxaca model the recently developed cotton neumark model is also used to derive estimates in a new twist to such models adjustments are made for the presence of selectivity bias in the data the results indicate existence of high levels of discrimination against women as reflected in estimates of the earnings differentials

real wages employment and the phillips curve a recent study by bils found real wages to be procyclical contradicting previous findings by geary and kennan who found no consistent relationship and neftci who found countercyclical movements in real wages these studies differed in both methodology and sample period in this study we found that real wages were either procyclical or countercyclical depending on the sample period chosen employment changes generated by aggregate supply shocks were associated with procyclical real wage movements while during years dominated by shifts in aggregate demand real wages were highly countercyclical

sticky wage or sticky price analysis of the cyclical behavior of the real wage the study of business cycles has been at the heart of macroeconomic theory for decades theoretical efforts have focused on providing an adequate explanation for sources of economic fluctuations new keynesian explanations have emphasized rigidity that interferes with market forces increasing the effect of demand shocks on the output produced the form of rigidity is in sharp contrast between sticky wage and sticky price models the former imposes rigidity on the shortrun adjustment of wages to demand shocks 20 47 the latter in contrast imposes rigidity on the short run price adjustment to demand shocks 2 34 40 9 43 4 the theoretical plausibility of competing explanations of business cycles has stimulated interest to establish their empirical validity 32 28 1 8 11 23 21 26 these efforts have focused attention on cyclical fluctuations of the real wage in response to demand shocks the real wage may move procyclically or countercyclically according to the relative adjustment of wages and prices the interest in studying the cyclical behavior of the real wage relates to its implications to the real effects of aggregate demand shocks in the context of sticky wage models nominal wage rigidity reinforces the countercyclical response of the real wage to demand shocks and the real effect of these shocks on output growth sticky price models in contrast advocate that price rigidity increases the procyclical response of the real wage to demand shocks and their real effect on output growth the results of earlier investigations of the cyclical behavior of the real wage appear conflicting and therefore do not lend support to a given explanation 2 the present investigation seeks to contribute to this literature unlike previous empirical research on the subject the objective of this investigation is to study the cyclical behavior of the real wage and the relative flexibility of the nominal wage and the price level that determines this behavior in response to demand shocks using data for the united states in the preand post world war ii sample periods the cyclical

gender and household education expenditure in pakistan pakistan has very large gender gaps in educational outcomes one explanation could be that girls receive lower educational expenditure allocations than boys within the household but this has never convincingly been tested this article investigates whether the intra household allocation of educational expenditure in pakistan favours males over females it also explores two different explanations for the failure of the extant engel curve studies to detect gender differentiated treatment in education even where gender bias is strongly expected using individual level data from the latest household survey from pakistan we posit two potential channels of gender bias bias in the decision whether to enrol keep sons and daughters in school and bias in the decision of education expenditure conditional on enrolling both sons and daughters in school in middle and secondary school ages evidence points to significant pro male biases in both the enrolment decision as well as the decision of how much to spend conditional on enrolment however in the primary school age group only the former channel of bias applies results suggest that the observed strong gender difference in education expenditure is a within rather than an across household phenomenon

environmental policy incentives to adopt advanced abatement technology abstract we investigate incentives through environmental policy instruments to adopt advanced abatement technology first we study the case where the regulator makes long term commitments to policy levels and does not anticipate arrival of new technology we show that taxes provide stronger incentives than permits auctioned and free permits offer identical incentives and standards may give stronger incentives than permits second we investigate scenarios where the regulator anticipates new technologies we show that with taxes and permits the regulator can induce first best outcomes if he moves after firms have invested whereas this does not always hold if he moves first

incentives for investment in advanced pollution abatement technology in emission permit markets with banking we examine the incentives that firms have to invest in cleaner abatementtechnology when the banking of permits is allowed in emission permittrading schemes we show that under certainty permit banking can distortincentives for investment and lead to a sub optimal amount of investmentspending under imperfect information aggregate abatement costuncertainty and investment irreversibility provide arguments for allowingbanking we generalize the model to consider these showing that somebanking is desirable but that it need not be the case that the privatebanking solution is optimal

instrument choice for environmental protection when technological innovation is endogenous this paper compares qualitatively and quantitatively the welfare effects of emissions taxes auctioned emissions permits and free grandfathered permits when technological innovation is endogenous we find that there is no unambiguous case for preferring any of these policy instruments the relative welfare ranking of instruments depends on the costs of innovation the extent to which innovations can be imitated the slope and level of the marginal environmental benefit function and the number of polluting firms we illustrate the types of situations when there can be significant welfare discrepancies between the policies and when there are not

multivariate estimates of the permanent components of gnp and stock prices the economic assumption that a present value relation holds between consumption and income and between stock prices and dividends or the statistical assumption that the consumption income ratio and the dividend price ratio are stationary imply that the permanent or random walk component in each series of a pair must be the same as the permanent component in the other series of a pair either assumption then allows us to estimate the variance of the permanent component of one series gnp stock prices from the variance of the permanent component of the other consumption dividends or from the covariance of the two series permanent components this paper presents such estimates and finds that the permanent components are about half those estimated by similar univariate methods a series of recent papers has examined the importance of a potential unit root to the behavior of real gnp campbell and mankiw 1986 1987 cochrane 1986 clark 1987 and stock prices fama and french 1986 lo and mai if by 0 the series is stationary the response can be any real number which is the innovation in these estimates instead of forcing us to ask the dichotomous question is there a unit root or not they allow us to continuously measure the importance of a potential unit root the actual estimating technique used in these papers varied somewhat cochrane poterba and summers and lo and mai if a series is stationary the variance of k differences will tend to a precursor to this paper appeared under the title spectral density estimates of unit roots we thank masanao aoki lam hansen masao ogaki and chris sims for helpful suggestions the computer programs and data used in this paper are available on request from the authors

toward a new conception of the environment competitiveness relationship accepting a fixed trade off between environmental regulation and competitiveness unnecessarily raises costs and slows down environmental progress studies finding high environmental compliance costs have traditionally focused on static cost impacts ignoring any offsetting productivity benefits from innovation they typically overestimated compliance costs neglected innovation offsets and disregarded the affected industry s initial competitiveness rather than simply adding to cost properly crafted environmental standards can trigger innovation offsets allowing companies to improve their resource productivity shifting the debate from pollution control to pollution prevention was a step forward it is now necessary to make the next step and focus on resource productivity

learning about environmental damage implications for emissions trading in this paper the impact of adjusting the supply of tradeable emission permits on incentives for cleaner technology adoption is examined two policy rules for adjusting the supply of permits are considered open market operations and a proportional adjustment rule under which the regulator expropriates permits from individual firms in proportion to their existing permit holdings adjustment via open market operations is neutral with respect to cleaner technology investment decisions but may be politically difficult to implement the proportional adjustment rule is also neutral with respect to investment decisions and at the same time allows more flexibility from a political perspective

stochastic trends and economic fluctuations are business cycles mainly the result of permanent shocks to productivity this paper uses a long run restriction implied by a large class of real business cycle models identifying permanent productivity shocks as shocks to the common stochastic trend in output consumption and investment to provide new evidence on this question econometric tests indicate that this common stochastic trend cointegration implication is consistent with postwar u s data however in systems with nominal variables the estimates of this common stochastic trend indicate that permanent productivity shocks typically explain less than half of the business cycle variability in output consumption and investment copyright 1991 by american economic association

the net present value method versus the option value of waiting a note on farzin huisman and kort 1998 abstract using the tools of real options theory farzin huisman and kort 1998 investigate the optimal timing of technology adoption in a model in which there is ongoing technological progress and the firm s investment decision is irreversible when the firm can switch technologies n farzin et al 1998 obtain the surprising result that the criterion for adopting a new technology derived from real options theory coincides with the net present value criterion for all but the last switch this note points out a mistake in farzin et al s 1998 derivations that leads to the above result we show that compared to the net present value approach the firm will defer the adoption of a new technology when it takes the option value of waiting into account

market efficiency and cointegration an application to the sterling and deutschemark exchange markets abstract the assumption that the foreign exchange market is efficient that is that agents are risk neutral and use all available information rationally so that the forward exchange rate is an unbiased predictor of the future spot rate is a property often imposed in theoretical international macroeconomic models although a vast empirical literature has evolved to test market efficiency we use recent developments in the theory of cointegration to provide new methods of testing several aspects of foreign exchange market efficiency we ffind evidence inconsistent with market efficiency for both germany and the united kingdom

emission taxes and optimal refunding schemes abstract we examine how refunding emission taxes to firms dependent on market shares should be designed while refunding is harmful under perfect competition a first best self financing tax tax refunding scheme exists if the marginal damage from pollution exceeds the marginal distortion in an imperfectly competitive output market with symmetric firms under pre investment in cleaner technology with short term abatement opportunities a first best refunding scheme exists if pollution refunding can be made dependent on both market and investment shares

unskilled urban migrant women and disguised employment home working women in istanbul turkey abstract formal and informal labor market opportunities for women are examined for turkey data collected from three surveys are used to describe types of home work and hourly wages are imputed for home work to compare with formal sector wages the number of migrant women who take home work in the city of istanbul is estimated

the relative adjustment of wages and prices direct tests within a multiple equation system in order to assess the relative rigidity of the aggregate price level and the nominal wage rate most researchers have focused on the implied behaviour of the real wage rate in response to a purely demand disturbance the present work examines the explicit behaviour of the two variables and is therefore able to analyse the variables short run responses within the context of their defined long run behaviour while the paper reports evidence of long run stability in the real wage rate additional evidence is presented which supports both sticky price and sticky wage models the determining factor is the choice of lag

the innovation effects of environmental policy instruments a typical case of the blind men and the elephant abstract in this paper we examine the innovation effects of environmental policy instruments in four literatures theoretical models on incentives for eco innovation econometric studies based on observed data survey analysis based on stated information and technology case studies the aim of this paper is to critically examine the methods and the results we argue that the case studies literature even when its results are specific and difficult to generalise is a necessary source of empirical evidence about policy impacts and the factors responsible for these impacts pointing to issues that are neglected in the theoretical and econometric literature such as the specifics of the innovation context and policy interaction effects the paper states five synthesised findings and makes a plea for multi method analysis one other important synthesised finding is that the influence of market based instruments on innovation such as emission trading and taxes is far weaker than assumed

production growth and business cycles ii new directions abstract this paper outlines new directions for investigations of real business cycle models consideration of stochastic growth of exogenous and endogenous forms analysis of suboptimal outcomes arising due to externalities of distorting taxes and implications of labor market heterogeneity

employers discriminatory behavior and the estimation of wage discrimination this paper considers the linkage of empirical estimates of wage discrimination between two groups introduced by oaxaca 1973 to a theoretical model of employers discriminatory behavior it is shown that conditional on different assumptions about employers discriminatory tastes oaxaca s estimators of wage discrimination can be derived that the approach is more generally useful is demonstrated by deriving an alternative estimator of wage discrimination based on the assumption that within each type of labor e g unskilled skilled the utility function capturing employers discriminatory tastes is homogeneous of degree zero with respect to labor inputs from each of the two groups the estimators are compared empirically in an application to male female wage differentials

market power and transferable property rights the appeal of using markets as a means of allocating scarce resources stems in large part from the assumption that a market will approximate the competitive ideal when competition is not a foregone conclusion the question naturally arises as to how a firm might manipulate the market to its own advantage this paper analyzes the issue of market power in the context of markets for transferable property rights first a model is developed that explains how a single firm with market power might exercise its influence this is followed by an examination of the model in the context of a particular policy problem the control of particulate sulfates in the los angeles region

pollution permits and compliance strategies abstract this paper analyzes the impact of spot and futures markets for tradeable pollution permits on the potential polluters compliance decisions polluters can buy permits invest in pollution abatement or else stop production or source out we show that stand alone spot markets induce excessive investment the introduction of a futures market reduces this incentive to invest but is not the optimal way to control pollution a menu of options on pollution rights possibly coupled with intertemporally bundled sales yields higher welfare because of its focus on long run demand elasticities and rent extraction this paper can be applied to a variety of situations such as demand side management public transportation bypass in telecommunications or forward sales by a private monopolist

does the labour market explain lower female schooling in india labour market discrimination against women and parental discrimination against daughters are two of the most commonly cited explanations of the gender gap in education in developing countries this study empirically tests the labour market explanation for india using recent household survey data the results reveal substantial omitted family background bias in the estimates of rates of return to education the findings suggest that as well as overall labour market discrimination girls face poorer economic incentives to invest in schooling than boys because they reap lower labour market returns to education than boys

male female wage differentials and policy responses without implicating them for any of the contents of the paper i am grateful to the following for helpful discussions or comments andrea beller university of illinois david bloom harvard and columnbia glen cain university of wisconsin ron ehrenberg cornell victor fuchs stanford bob gregory australian national university jonathan leonard university of california berkeley roberta robb brock university and paul weiler harvard financial support of the humanities and social sciences committee of the research board of the universitu of toronto is eratefullu acknowlede ed

incentives for advanced pollution abatement technology at the industry level an evaluation of policy alternatives abstract in this research we evaluate the incentive effects of five environmental policy instruments to promote the development and adoption of advanced pollution abatement technology in a heterogenous industry from most to least incentive the policy instruments can be rank ordered as follows i auctioned permits ii emissions taxes and subsidies iii issued marketable permits iv performance standards including performance standards in this list necessitates the assumption that they are differentiated between heterogeneous firms before the technology adoption in a way which replicates the initial emissions control distribution of the efficient incentive based instruments with the starting point normalized in this fashion the instrument rankings are invariant with respect to the size of firms the size of the industry or the industry s abatement cost structure

the employment real wage relationship an international study the neoclassical and keynesian theories of employment both predict an inverse relationship between employment and real wages in the short run the observed correlation between employment and real wages however has usually failed to conform to this prediction dunlop 1938 and tarshis 1939 reported a positive correlation between real and money wages which given procyclical movement of money wages was interpreted as evidence against the theoretical prediction the statistical significance of these results was however challenged by ruggles 1940 and tobin 1948 more recent studies by kuh 1966 and bodkin 1969 failed to detect a significant relationship between real wages and employment these findings stimulated a series of contributions by solow and stiglitz 1968 barro and grossman 1971 1976 and others developing alternative models not apparently refuted by the evidence barro and grossman recast macro theory under the assumption that markets did not clear modigliani 1977 argued that the observed relationship between employment and real wages could be accounted for in an oligopolistic model of firm behavior thus both the competitive and equilibrium assumptions of the classical model were diagnosed as the sources of its apparent empirical refutation

optimal pollution standards and non compliance in a dynamic framework in this paper we present a stackelberg differential game to study the dynamic interaction between a polluting firm and a regulator who sets pollution limits overtime at each time the firm settles emissions taking into account the fine for non compliance with the pollution limit and balances current costs of investments in a capital stock which allows for future emission reductions we derive two main results first we show that the optimal pollution limit decreases as the capital stock increases while both emissions and the level of non compliance decrease second we find that offering fine discounts in exchange for firm s capital investment is socially desirable we numerically obtain the optimal value of such discount which crucially depends on the severity of the fine in the limiting scenario with a very large severity of the fine the optimal discount implies that no penalties are levied since the firm shows adequate adaptation progress through capital investment

heteroskedastic sample selection and developing country wage equations many researchers have dealt with potential selectivity bias in developing country wage equations by employing heckman s 1979 two step method or related techniques despite the potential for such methods to produce misleading results if the assumptions on which they are based are incorrect this paper argues that the results produced even by parametric easy to implement selectivity bias correction methods can inspire more confidence than the typical applications to date when model selection testing is used to select from a specified diverse set assumptions for which there is support in the data and when sensitivity analysis is used to identify parameters whose estimates are robust across a wide range of assumptions in particular it highlights the importance of allowing for the nonlinearities implied by selection rule heteroskedasticity there is economic reason to suspect heteroskedasticity and econometric reason to believe that the nonlinearities it introduces into the first stage will improve

inducing innovation in the environmental technology of oligopolistic firms this paper characterizes environmental regulations which induce polluting bertrand competitors to invest efficiently in environmental r d post innovation benefits to raising rivals costs provide firms with incentives to innovate although optimal behavior cannot be elicited with pollution taxes alone an optimum can be achieved by combining emission taxes with environmental performance standards that are higher for firms which reveal superior environmental technologies faced with this policy successful innovators voluntarily reveal their technological discovery to the government despite the apparent regulatory penalty that results implications for automotive fuel regulation are discussed

markets and regulatory hold up problems abstract many regulatory programs such as environmental regulation are effective only if firms make irreversible investments that reduce the cost of compliance a firm potentially subject to regulation may therefore behave strategically by not investing thereby forcing the regulator to void the proposed regulation we show that such incentives which resemble a hold up problem may not be overcome when government s only tool is the imposition of an emissions tax the hold up problem can be overcome by the issuance of tradeable permits a time consistent equilibrium exists with all firms investing and the government imposing regulations even if no permits are traded and their market price is low indeed an observation of no trade may indicate that pollution abatement is great

generating conditional expectations from models with selectivity bias comment abstract plugging identical values of the mills ratio into estimates of selectivity adjusted wage regressions for men and women generates wage predictions that pertain to men and women with identical unobserved characteristics only under highly restrictive conditions this calls into question the suggestion of vella 1988 and the details of several gender gap decomposition studies

optimal timing of technology adoption abstract in a dynamic programming framework this paper investigates the optimal timing of technology adoption by a competitive firm when technology choice is irreversible and the firm faces a stochastic innovation process with uncertainties about both the speed of the arrival and the degree of improvement of new technologies a numerical example illustrates how the optimal timing decision is affected by changes in parameter values reflecting market conditions the firm s initial technological attributes and the characteristics of the stochastic innovation process some of these effects turn out to be in sharp contrast to common intuition contrasting the optimal decision rule derived here with the rule obtained under the net present value shows that the former implies a slower pace of adoption than implied by the latter the optimal decision rule is generalized for the case of multiple technology switches and it is shown that for all the switching decisions except the last one the optimal rule satisfies the net present value criterion

innovation in pollution control comparisons of the various institutional arrangements for controlling pollutant emissions from individual sources effluent fees effluent control subsidies marketable permits and direct command and control regulation have usually focused on their static efficiency properties and institutional feasibility e g dales 1968 zerbe 1970 baumol and oates 1975 kneese and schultze 1975 marin 1978 mills and white 1978 spence and weitzman 1978 russell 1979 a relatively neglected area has been the study of how each arrangement influences innovation in pollution control a few studies e g kneese and schultze 1975 marin 1978 mills and white 1978 russell 1979 have casually claimed that the control methods that rely on economic incentives provide superior incentives for innovation but there have been few systematic studies of the question this paper provides a simple model of pollution control innovation by a profitmaximizing polluter who is subject to the various control methods the consequences of the methods will be explored in three major contexts first we assume that the polluter and the innovation is a small enough part of the overall pollution problem so that none of the important marginal conditions are changed by the innovation second we assume that the polluter and the innovation are important enough so that marginal conditions are changed by the innovations but that the governmental authority determining pollution control incentives or levels fails to make the appropriate adjustments third we again assume that the innovation causes marginal conditions to change but in this case the governmental authority makes the appropriate adjustments we use the term ratcheting to describe this last phenomenon in all cases we assume that the innovating polluter correctly predicts the reactions of the governmental authority and bases his innovation decisions on that prediction a profit maximizing entrepreneur would normally be expected to adopt any innovation that promised gains present discounted value to him in excess of initial

dynamic efficiency of extended producer responsibility instruments in a simulation model of industrial dynamics this article presents an original approach to the impact of extended producer responsibility instruments for waste prevention upon firms innovative strategies and market structure our analysis is based on a stylised framework of waste prevention developed by brouillat in this framework products are modelled as multi characteristic technologies whose evolution depends on firms innovation strategies and on the interactions with consumers and postconsumption activities recycling this stylised framework has been adapted to explore the impact of waste prevention instruments upon industrial dynamics and more particularly upon firms innovative strategies and upon the evolution of products characteristics and market structure we focus on two types of policy instruments recycling fees and norms for each instrument we will consider different policy designs in order to study their effects on industrial dynamics the main contribution of this article is to show how this type of simulation model can be used to explore the impact of waste prevention policy instruments on the technological evolution of products on innovation strategy and on the evolution of firms market shares the introduction of policy instruments in a simulation agent based model of industrial dynamics enables us to analyse more thoroughly how different policy designs can modify the dynamics of the system and more particularly how the incentives and the constraints linked to the policy instruments under consideration shape market selection copyright 2012 the author 2011 published by oxford university press on behalf of associazione icc all rights reserved oxford university press

dynamic incentives by environmental policy instruments a survey abstract in this paper i survey and discuss recent developments on the incentives provided by environmental policy instruments for both adoption and development of advanced abatement technology a main conclusion to be drawn from the literature is that under competitive conditions market based instruments usually perform better than command and control moreover taxes may provide stronger long term incentives than tradable permits if the regulator is myopic if the government can anticipate new technology or is able to react on it optimally regulatory policies by virtue of administered prices taxes and policies by setting quantities issuing tradable permits are almost equivalent the literature also shows that under competitive conditions there is no difference between auctioning permits and grandfathering moreover timing and commitment of environmental policy is not crucial for adoption under competitive conditions commitment has positive incentive effects however if an r d sector has market power in the presence of market imperfections the ranking of the different policy instruments is ambiguous

public policies and changing boundaries of firms in a history friendly model of the co evolution of the computer and semiconductor industries in this paper we explore the effects of alternative policies ranging from antitrust to public procurement open standards information diffusion and basic research support on the dynamics of two vertically related industries in changing and uncertain technological and market environments the two industries are a system industry and a component industry and the evolution of these industries is characterized by periods of technological revolutions punctuating periods of relative technological stability and smooth technical progress we have been inspired by the co evolution of the computer and component industries from their inceptions to the 1980s on the basis of that evolution we have developed a history friendly model this co evolution in sum this paper has stressed that various types of policies may sometimes have contrasting effects on the industry mainly on concentration and technical change and innovation it has also shown that the consequences of policies may spillover from one industry to another and from one type of firms to another policies that aim at a specific industry may provoke major changes in a related industry through the product market the changing boundaries of firms or knowledge and technological interdependencies the policy maker has to be aware of that finally a major point of the paper regards the unintended consequences of policies

demand shocks supply shocks and the cyclicality of real wages the behaviour of real wages over the business cycle has received increasiing attention in recent years the cyclicality of real wages constitues an important aspect of recent models of the business cycle however empirical studies undertaken to determine whether real wages are procyclical or countercyclical have reported conflicting findings in thiis paper we use vector autoregressions to analyse the cyclicality of real wages we find that the source of the disturbance plays a decisive role in the cyclical behaviour of real wages in particular we demonstrate that a supply shock generates procyclical real wages whereas a demand shock yields countercyclicality

a note on permits standards and technological innovation abstract montero j environ econom manage 44 2002 23 contrasts the incentives to invest in new abatement technologies under different regulatory instruments and argues that one needs to consider the induced output effects that derive from lower abatement costs montero shows that once one takes into account these effects on output command and control instruments can generate stronger incentives to innovate than market based instruments this result rests on strategic output effects under command and control however he maintains that under perfectly competitive conditions market based instruments will continue to weakly dominate command and control regulation this note clarifies two issues raised by montero first i use montero s approach to show that in fact performance concentration standards will generate greater incentives to innovate than market based instruments in perfectly competitive markets one does not require strategic effects to get this result second montero abstracts from production costs and concentrates solely on abatement costs he implicitly assumes that marginal production costs are constant i show that some of montero s results change once increasing marginal production costs are considered when marginal costs are increasing the benefit of additional output is tempered and market based instruments again look more favorable

on the decomposition of wage differentials the often used method for decomposing wage differentials into human capital and discrimination components is reformulated so that both t he disadvantage or cost discrimination it imposes on a black or minority wage earner and the advantage or benefit it bestows on a white or majority wage earner can be estimated copyright 1988 by mit press

real wages and the business cycle the objectives of this review are threefold 1 to characterize the empirical literature on the cyclical behavior of real wages 2 to identify the sources of the differences in results across studies and 3 to enumerate key factors that determine the cyclicality of real wages given a host of measurement and methodological issues drawing firm conclusions is difficult but several generalizations can be made the estimated cyclicality of real wages depends crucially on the time period of analysis and the choice of whether to examine the production or the consumption wage composition effects play an important but complicated role as well

timing and commitment of environmental policy adoption of new technology and repercussions on r d we investigate the interplay between environmental policy incentives to adoptnew technology and repercussions on r d we study a model where a monopolistic upstream firm engages in r d and sells advanced abatement technology to polluting downstream firms we consider four different timing and commitment regimes of environmental tax and permit policies ex post taxation or issuing permits interim commitment to a tax rate a quota of permits after observing r d success but before adoption and finally two types of ex antecommitment before r d activity one with a unique tax rate quota of permits the other one with a menu of tax rates permit quotas we study the second best tax and permit policies and rank these with respect to welfare in particular we find that commitment to a menu of tax rate dominates all other policy regimes

the relative stickiness of wages and prices i introduction a continuing challenge to macroeconomics is to explain how a purely nominal disturbance produces short term aggregate real effects in the classical paradigm in which wages and prices are perfectly flexible a positive nominal aggregate demand disturbance will cause nominal wages and output prices to rise in the same proportion leaving real wages unchanged thus neither employment nor output will be affected consequently many business cycle theories posit the existence of wage and or price stickiness to explain how nominal aggregate demand disturbances generate real macroeconomic effects according to these theories the failure of nominal wages or prices to fully adjust in the short run to purely nominal disturbances explains why shocks to aggregate demand will cause both employment and output to temporarily deviate from their natural rates the relative importance of wage and price stickiness in the transmission of nominal shocks to the real economy however remains an unsettled issue the purpose of this paper is to exploit evidence on the behavior of real wages in an attempt to assess the relative importance of these two sources of stickiness first consider models emphasizing sticky or slowly adjusting nominal wages 1 if for example output prices are free to adjust but nominal wages are sticky a positive aggregate demand shock will cause prices to rise and real wages to temporarily fall below market clearing levels the fall in real wages will stimulate employment and thus output as the aggregate demand shock induces movement along a stable labor demand curve consequently sticky wage models predict a negative correlation between aggregate demand shocks and real wages if on the other hand wages are flexible while output prices are sticky 2 aggregate demand disturbances and real wages will tend to be positively correlated in the short run in sticky price models imperfectly competitive firms may resist adjusting output prices in response to changes in demand perhaps due to menu costs instead increases in demand are met by corresponding increases in output this requires an increase in labor inputs which in turn requires an increase in the real wage rate if wages are flexible and the labor supply curve is positively sloped thus when prices are sticky but wages are flexible a positive aggregate demand shock is associated with an increase in real wages it may be that neither prices nor wages are fully flexible if prices and wages both exhibit stickiness we would expect real wages to be positively correlated or negatively correlated with aggregate demand shocks depending in large part on whether prices or wages are stickier thus knowledge of the direction of the short run response of real wages to aggregate demand disturbances would offer important evidence on the relative stickiness of nominal wages and output prices if all business cycle fluctuations are due solely to aggregate demand disturbances such evidence could be obtained by examining the cyclical behavior of real wages since regardless of the source of stickiness aggregate demand disturbances are positively correlated with employment and output countercyclical procyclical real wages would indicate that nominal wages are stickier more flexible than output prices indeed some consider the stylized fact of slightly procyclical real wages 3 to be an important challenge to models that emphasize wage stickiness for example bennett mccallum 1986 argues for the superiority of models with sticky output prices since if wage stickiness alone were responsible for the real effects of monetary actions with product prices adjusting flexibly then we should observe countercyclical movements in the real wage that we do not has recently been reconfirmed in a study by bils 1985 gregory mankiw 1987 107 has concluded the final and perhaps most serious problem with the unadorned nominal wage story is that real wages do not move over the business cycle as the theory predicts

does host market regulation induce cross border environmental innovation this paper evaluates the effect of host country environmental policy stringency on the offshoring of environmental patents for 2000 top world r d performers it is shown that a more stringent environmental regulation triggers both the extensive and intensive margin of patent offshoring in the field of environmental technologies results are robust to various different specifications alternative definitions of innovation offshoring and of regulation restrictions and to the consideration of possible endogeneity of regulation it is suggested inter alia that r d subsidies and non market based regulatory measures are more important than market based instruments as drivers of cross border environmental innovation length 26 pages

voluntary disclosure and investment in environmental technology abstract i examine the role of voluntary disclosure programs in creating market incentives for competing firms to invest in environmentally cleaner technology in an industry subject to environmental regulation such as emission taxes such programs may allow firms to credibly disclose their progress in achieving compliance cost reduction through investments in internal rd the outcome of the investment is private information i show that the ex ante incentive to invest is always higher in the presence of the voluntary disclosure program than without it in particular the opportunity to credibly disclose progress in cost reduction allows a successful firm to convey its true position of competitive advantage to the rival firm and realize higher market share and profit thus voluntary disclosure programs increase the efficacy of traditional forms of environmental regulation in creating incentives for green technological change even when buyers have no preference for greener technology i show that such programs generally increase social welfare

innovation and the international diffusion of environmentally responsive technology abstract new evidence is presented on environmental innovation and diffusion over the 1970s and 1980s at a global level a substantial amount of innovations occurred in the united states japan and germany the share of environmental patents in all patents varied between 0 6 and 3 and as such was higher than the corresponding share of pollution abatement expenditure in gdp japanese environmental innovation rates were consistently high certain plausible connections between environmental regulation and innovation also emerge across these three countries and over time innovation responded to pollution abatement expenditure an indicator of the severity of environmental regulations environmental patenting rates in developing countries were also high reaching 2 in many years in brazil developing country innovators obtained a non trivial number of patents most of which appear geared towards adapting imported technologies to local conditions however domestic innovation was only one path to new technologies imports of disembodied environmental technologies foreign patents registered in developing countries were substantial foreign patents were typically important or generic patents evidence also suggests that such patents protected intellectual property in equipment exported developing countries especially in east asia often chose to obtain technologies embodied in pollution abatement equipment

optimal policies for solid waste disposal taxes subsidies and standards abstract pricing trash collection and disposal services can be politically unpopular and may lead to increased illegal disposal of trash several studies have shown that deposit refund systems can act like disposal charges without the illegal disposal problem and thus can generate an optimal amount of solid waste disposal we assess the efficiency implications of an alternative policy currently in use in some states in the u s and considered at the federal level recycled content standards these are requirements that a certain fraction of total material use in production be comprised of secondary materials we find that such standards by themselves cannot generate the optimal amount of disposal but must be combined with additional taxes on both the final product and other inputs to production moreover the information requirements for setting the optimal standards and accompanying taxes are high the deposit refund approach would be preferred in most cases

inventor networks in renewable energies the influence of the policy mix in germany technological change and gains in efficiency of renewable power generation technologies are to a large extent driven by governmental support various policy instruments that can broadly be categorized as technology push demand pull or systemic constitute part of the policy mix for renewable energies our goal is to gain insights into the influence of this policy mix on the intensity and organization of inventive activities for wind power and photovoltaics in germany since the 1980s we examine the effect of different instruments on the size and structure of co inventor networks based on patent data our results indicate notable differences between the technologies the network size for wind power is driven by technology push and systemic instruments while in photovoltaics demand pull is decisive for network growth by and large the instruments complement each other and form a consistent mix of policy instruments the structure of the networks is driven by demand pull for both technologies systemic instruments increase interaction especially in the wind power network and are complementary to demand pull in fostering collaboration

the merits of new pollutants and how to get them when patents are granted the performance of market based environmental regulation is affected by patents and vice versa this interaction is studied for a type of innovation where a new technology reduces emissions of a specific pollutant but at the same time causes a new type of damage if the new pollutant associated with this technology is sufficiently different from existing ones such that marginal damage is increasing in each of them but additive across pollutants a diversification of the pollution portfolio is socially desirable in a situation where the incentives to develop such a technology are created by patents the efficiency of permits is affected by monopoly pricing of the patent holding firm this result carries over to other types of innovation the performance of taxes is limited by either the inability to implement specific pollution mixes or monopoly pricing for constant returns to scale at the industry level the combined use of taxes and permits ensures the first best mix of technologies and provides positive research incentives