computer use and earnings in britain this paper estimates various models of the effect of computer use on earnings using recent ncds data the cross section estimates are large and significant while the standard fixed effects estimates are small or insignificant the panel estimates change considerably once we allow the coefficients to differ across individuals conditional on assumptions about when individuals use computers conventional panel estimates may not identify the crucial parameters and alternative methods are needed we conclude that there was a substantial premium associated with computer use for some individuals in the uk

if not computers then what returns to computer use in the uk revisited in recent years much attention has been paid to the effect on wages of skill biased technology especially the use of computers although empirical studies have shown a positive relationship between computer use and earnings doubts have been cast on whether this is a causal relationship or merely represents unobserved other factors which are themselves positively linked to computer usage this study provides evidence that computers themselves raise wages although their impact on wages falls as other controls are included in the regression it still remains significant whilst the effect of another proxy for unobserved factors becomes insignificant furthermore improvements in computer use have an additional impact on earnings supporting the productivity interpretation

spatial evolution of social norms in a common pool resource game we study the conditions for the emergence of cooperation in a spatial common pool resource cpr game we consider three types of agents cooperators defectors and enforcers the role of enforcers is to punish defectors for overharvesting the resource agents are located on a circle and they only observe the actions of their two nearest neighbors their payoffs are determined by both local and global interactions and they modify their actions by imitating the strategy in their neighborhood with the highest average payoffs on average using theoretical and numerical analysis we find a large diversity of equilibria to be the outcome of the game in particular we find conditions for the occurrence of equilibria in which the three strategies coexist we also derive the stability of these equilibria finally we show that introducing resource dynamics in the system favors the occurrence of cooperative equilibria

an evolutionary approach to norms iorms provide a powerful mechanism for regulating conflict in groups even when there are more than two people and no central authority this paper investigates the emergence and stability of behavioral norms in the context of a game played by people of limited rationality the dynamics of this new norms game are analyzed with a computer simulation based upon the evolutionary principle that strategies shown to be relatively effective will be used more in the future than less effective strategies the results show the conditions under which norms can evolve and prove stable one interesting possibility is the employment of metanorms the willingness to punish someone who did not enforce a norm many historical examples of domestic and international norms are used to illustrate the wide variety of mechanisms that can support norms including metanorms dominance internalization deterrence social proof membership in groups law and reputation

stream ecosystem service markets under no net loss regulation abstract we analyze interactions between economics and ecology for ecosystem service markets under no net loss regulation previous studies of no net loss regulation address the ecological efficacy and valuation of restoration but largely ignore the effects of market dynamics we link an economic model of free entry equilibria with an ecological model that includes returns to scale and inefficiency of restored ecosystems and apply the result to stream mitigation banking in north carolina intuition from ecology alone must be modified to account for economic processes and vice versa to implement no net loss regulation one must not only account for ecological differences between restored and natural ecosystems but also consider the effect of market entry on the number and size of restoration projects in a purely economic model free entry equilibria are characterized by excess entry the equilibrium number of firms is greater than the welfare maximizing number ecological considerations may exacerbate or ameliorate this so that either excess entry or insufficient entry may occur depending on the specific ecosystem services sought

coordination cooperation contagion and currency crises we analyze the effect of trade competition international coordination and cooperation on currency crises to do this we present a micro founded model where governments have an incentive to devalue to increase the national market share in a monopolistically competitive sector currency crises generated by self fulfilling expectations are possible because private agents demand high wages when they expect a devaluation this decreases the competitiveness and profits of national firms and induces the government to devalue we show that the more important trade competition the more likely self fulfilling speculative crises are and the larger the set of multiple equilibria coordination decreases the possibility of simultaneous self fulfilling speculative crises in the region and reduces the set of multiple equilibria however regional coordination even though welfare improving makes countries more dependent on other countries fundamentals so that it may induce more contagion cooperation further reduces the set of multiple equilibria with currency crises

the transmission of sustainable harvesting norms when agents are conditionally cooperative experimental and observational studies have highlighted the importance of agents being conditionally cooperative when facing a social dilemma we formalize this mechanism in a theoretical model that portrays a small community having joint access to a common pool resource the diffusion of norms of cooperation takes place via interpersonal relations while individual agents face the temptation of higher profits by overexploiting the resource agents remain conditionally cooperative unless other individuals are misbehaving already we can observe a bubble of conditional cooperators slowly building up followed by a sudden burst which means that a transition from a cooperative social norm to non cooperation occurs interestingly in some parameter regions alternative stable states and limit cycles arise the latter implies that the same community goes through such a transition repeatedly over long time spans history thus repeats itself in the form of the creation and erosion of social capital

on the empirics of social capital this paper critically examines the way in which empirical evidence is developed in support of a role for social capital in socioeconomic outcomes three leading studies of social capital are reviewed and in each case argued to suffer from various identification problems a general set of conditions under which social capital effects may be identified in linear models is given careful attention to these conditions combined with greater openmindedness as to what constitutes appropriate evidence seems the best route to improving empirical studies of social capital

technology and the wage structure this article reports direct evidence on how technological change is related to changes in wage gaps by schooling experience and gender wage gaps by schooling increased the most in industries with rising r d intensity and accelerating growth in the capital labor ratio estimates of their relationship to high tech capital are inconclusive contrary to popular notions that technological change harms older workers wage growth of experienced workers is much greater in r d intensive industries than in industries with little r d activity the gender gap narrowed more in industries that most intensively used high tech capital in 1979

household income dynamics a four country story in this article we analyse the dynamics of household per capita incomes using longitudinal data from indonesia south africa spain and venezuela we find that in all four countries reported initial income and job changes of the head are consistently the most important variables in accounting for income changes overall and for initially poor households we also find that changes in income are more important than changes in household size and that changes in labour earnings are more important than changes in other sources of household income

computer use and wages evidence from taiwan we find a significant positive relationship between computer use and wages using taiwan microdata controlling for endogeneity of computer use with simultaneous equations suggests that although ols estimates are biased upward workplace computer use increases productivity d 2003 elsevier b v all rights reserved

industry level emission trading between power producers in the eu in this paper we investigate how restrictions for emission trading to the energy intensive power sector will affect the magnitude and distribution of abatement costs across eu countries vis a vis a comprehensive eu emission trading regime we find that emission trading between european power sectors allows the harvest of a major part of the efficiency gains provided by full trade as compared to strictly domestic action however trade restrictions may create a more unequal distribution of abatement costs across member states than is the case for a comprehensive trade regime the reason for this is that restricted permit trade enhances the secondary terms of trade benefits to eu member countries with low marginal abatement costs at the expense of the other eu member states

behaviour in commons dilemmas homo economicus and homo psychologicus in an ecological economic model in mainstream economy behaviour is often formalised following the rational actor approach however in real life the behaviour of people is typified by multidimensional optimisation to realise this people engage in cognitive processes such as social comparison imitation and repetitive behaviour habits so as to efficiently use their limited cognitive resources a multi agent simulation program is being developed to study how such micro level processes affect macro level outcomes sixteen agents are placed in a micro world consisting of a lake and a gold mine each agent s task is to satisfy its personal needs by fishing and or mining whereby they find themselves in a commons dilemma facing the risk of resource depletion homo economicus and homo psychologicus are formalised to study the effects of different cognitive processes on the agents behaviour results show that for the h psychologicus the transition from a fishing to a mining society is more complete than for the h economicus moreover introducing diversity in agents abilities causes the h economicus on the average to decrease its time spent working whereas for the h psychologicus we observe an increase in the time spent working these results confirm that macro level indicators of sustainability such as pollution and fish harvest are strongly and predictably affected by behavioural processes at the micro level it is concluded that the incorporation of a micro level perspective on human behaviour within integrated models of the environment yields a better understanding and eventual management of the processes involved in environmental degradation 2000 elsevier science b v all rights reserved

computers skills and wages computer technology is most prominently used by skilled high wage workers this suggests that computer use requires skills to take full advantage of the possibilities which are particularly present among relatively skilled workers this article develops a simple technology adoption model showing that the decision to adopt computer technology depends on i the tasks to be performed ii the level of skill or education and iii the level of wages applying this model to british data it is shown that the effect of wages and particular tasks on computer adoption is larger than the effect of skills on adoption the estimates suggest that in britain computer use is likely to be a matter of cost efficiency and not so much of workers skills

levels of computer self efficacy computer use and earnings in china abstract levels of self efficacy in computer use were found to be positively related to computer use at work among a sample of workers in shanghai the simultaneous estimation of computer use and earnings indicated that an earnings premium for computer use accrues only to females not to males

what happens when agent t gets a computer the labor market impact of cost efficient computer adoption this paper offers a model of how computer technology has changed the labor market demonstrating that wage differentials between computer users and non users are consistent with computers first being introduced in high wage jobs following cost efficiency furthermore skill upgrading occurs following a reemphasis on non routine tasks after adoption the model also reveals that neither differences in computer skills nor complementary skills are needed to explain wage differentials between users and non users skill upgrading and the changing organization and intensity of work finally the predicted effects on the wage structure are consistent with empirical evidence

conditional cooperation and voluntary contributions to public goods we compare a partners condition where the same small group of subjects plays a repeated publi c good game to a strangers condition where subjects play this game in changing group formations subjects in the partners conditi on contribute from t he first period on significantly more to the publi c good than subjects in the strangers conditi on in the strangers conditi on contributions show a continual decay whil e in the partners conditi on contributions fluctuate on a high level until t hey decrease in the final periods we interpret subjects behavior in terms of conditional cooperation which is characterized by both future oriented and reactive behavior

the price of a price on the crowding out and in of social norms we study the impact of financial incentives on social approval showing that in a society with altruists and egoists who all care about social approval introducing financial incentives to agents to contribute to a socially desirable outcome may actually decrease the number of contributions withdrawing the financial incentive does not restore the norm to contribute and may reduce the level of contributions even further when the norm has disappeared it may be possible to restore voluntary contributions by first introducing high price and then reducing it but such an operation is costly and its success uncertain

chains of cooperation threshold effects in collective action granovetter s threshold model of collective action shows how each new participant triggers others until the chain reaction reaches a gap in the distribution of thresholds hence outcomes depend on the network of social ties that channel the chain reactions however structural analysis is encumbered by the assumption that thresholds derive from changing marginal returns on investments in public goods a learning theoretic specification imposes less stringent assumptions about the rationality of the actors and is much better suited to a structural analysis computer simulations suggest that threshold effects may be the key to solving the coordination problem when individual choices are contingent on participation by others this interdependence facilitates the coordination of contributions needed to shift the bistable system from a noncooperative equilibrium to a cooperative one further simulations with low density networks show that these chain reactions require bridges that link socially distant actors supporting granovetter s case for the strength of weak ties

endogeneity computers language skills and wages among university graduates in vietnam one would expect that returns to supplementary skills in developing countries are considerably higher compared to those documented for developed countries as is the case with returns to schooling i derive estimates of returns to the use of computer and foreign language skills in vietnam after controlling for endogeneity using a binary instrument hypothesized to reflect reconstruction doi moi policies in vietnam i find that a the use of both computers and language skills is associated with very large earnings premiums b iv return estimates are as high as and sometimes higher than ols estimates however they should be interpreted in relation to the instrument used

innovation diffusion in heterogeneous populations contagion social influence and social learning new ideas products and practices take time to diffuse a fact that is often attributed to some form of heterogeneity among potential adopters this paper examines three broad classes of diffusion models contagion social influence and social learning and shows how to incorporate heterogeneity into each at a high level of generality without losing analytical tractability each type of model leaves a characteristic footprint on the shape of the adoption curve which provides a basis for discriminating empirically between them the approach is illustrated using the classic study of ryan and gross 1943 on the diffusion of hybrid corn

computers and the changing skill intensity of jobs this paper investigates the impact of computer usage at work and other job features on the changing skills required of workers it compare skills utilization in britain at three data points 1986 1992 and 1997 using proxies for the level of skills actually used in jobs this study questions the validity of investigating the facts about and the sources of rising skills by using just educational attainment or occupational grouping data this paper finds that job skills have increased more quickly for women than for men these increases are more extensive than those captured by changes in the occupational class structure the spread of computer usage is very strongly associated with the process of upskilling and accounts in part for narrowing of the gender skills gap expanded use of quality circles is also linked to upskilling evidence for any direct role of trade in inducing skills increases is weak using the qualification held or occupation as a skills measure can lead to erroneous conclusions as to the origin of skills changes

new technologies wages and worker selection we study the effect of new technologies nt on wages and employment using a unique panel that matches data on individuals and on their firms as in the united states we show that computer users are better paid than nonusers 15 20 more but these workers were already better compensated before the introduction of the nts total returns to computer use amount to 2 measurement errors do not affect our estimates furthermore computer users are protected from job losses as long as bad business conditions do not last too long this result holds even after controlling for possible selection biases

incentive contracts for natura 2000 implementation in forest areas the implementation of nature conservation policy is often based on contracts between public authorities and landowners in this article we model incentive contracts in forest areas in the presence of adverse selection and moral hazard when the conservation outcome is uncertain ex ante but observable ex post the results show that agents who are likely to achieve a higher level of conservation should be offered a contract where transfers depend on the final outcome with a bonus for a high ecological level of the forest when conservation measures are correlated with forest management we show that the contractual measures involve distorted transfers we analyse the payment mechanisms used in france and denmark in the context of the natura 2000 policy these mechanisms result in overcompensation and under performance since they do not take the problem of moral hazard and natural variability into account

contagious cooperation temptation and ecosystem collapse real world observations suggest that social norms o f cooperation can be effective in overcoming social dilemmas such as the joint management of a c ommon pool resource but also that they can be subject to slow erosion and sudden collapse we show that these patterns of erosion and 15 collapse emerge endogenously in a model of a closed community harvesting a renewable natural resource in which individual agents face the tempta tion to overexploit the resource while a cooperative harvesting norm spreads through the community via interpersonal relations we analyze under what circumstances small changes in key parameters including the size of the community and the rate of technological progress trigger catastrophic transitions from 20 relatively high levels of cooperation to widespread norm violation causing the social ecological system to collapse

property rights regimes and natural resources a conceptual analysis the term common property resource is an example of a term repeatedly used to refer to property owned by a government or by no one it is also used for property owned by a community of resource users such usage leads to confusion in scientific study and policy analysis in this paper we develop a conceptual schema for arraying property rights regimes that distinguishes among diverse bundles of rights ranging from authorized user to claimant to proprietor and to owner we apply this conceptual schema to analyze findings from a variety of empirical settings including the maine lobster industry

on the uniqueness of equilibrium in cournot oligopoly and other games abstract in an average surplus sharing game such as a cournot oligopoly a group of agents share a production process each contributes an amount of input to the process and output is divided in proportion to the amount of input contributed uniqueness of the equilibrium is needed for any type of comparative static analysis however general uniqueness results for concave games have restrictive assumptions on preferences and technology specifically the conditions needed for uniqueness become more difficult to meet as the number of players increases a new theorem for uniqueness with easily interpretable conditions is given which is independent of the number of players journal of economic literature classification numbers c70 c72 d43

make money surfing the web the impact of internet use on the earnings of u s workers much research on the digital divide presumes that adults who do not use the internet are economically disadvantaged yet little research has tested this premise after discussing several mechanisms that might produce differences in earnings growth between workers who do and do not use the internet we use data from the current population survey to examine the impact of internet use on changes in earnings over 13 month intervals at the end of the internet boom our analyses reveal robustly significant positive associations between web use and earnings growth indicating that some skills and behaviors associated with internet use were rewarded by the labor market consistent with human capital theory current use at work had the strongest effect on earnings in contrast to economic theory which has led economists to focus exclusively on effects of contemporaneous workplace technology use workers who used the internet only at home also did better suggesting that users may have benefited from superior

profit fluctuations signal eroding resilience of natural resources abstract a common pattern of environmental crises is a vicious cycle between environmental degradation and socio economic disturbances here we show that while such feedbacks may give rise to critical transitions in social ecological systems at the same time they can offer novel opportunities for anticipating them we model a community that has joint access to the harvest grounds of a resource that is prone to collapse individuals are tempted to overexploit the resource while a cooperative harvesting norm spreads through the community via interpersonal relations both social and ecological collapses can be induced by environmental or socio economic driving forces regardless of the type and cause of collapse we find that upcoming transitions may be detected using simple socio economic response variables such as individual profits our findings suggest that such alternative sources of information can be used to detect upcoming critical transitions in social ecological systems however we also find that robust detection of critical transitions may be confounded by recovery attempts undertaken by resource users in the vicinity of an upcoming collapse which may be falsely interpreted as a stabilization of the social ecological system

no man is an island social coordination and the environment humans are fundamentally social social activities require coordination possibly leading to multiple equilibria in the form of self reinforcing patterns of herd behavior when alternative equilibria differ substantially with respect to environmental damage they represent virtuous and vicious cycles from an environmental perspective such cycles can be sustained by network effects social pressure to conform or other mechanisms directly or indirectly yielding coordination benefits breaking the vicious cycles can be an important task for environmental policies i present a stylized model of social coordination with environmental externalities using it to discuss how environmental policies may help agents coordinate in more environment friendly ways

nonlinear behavior of the socio economic dynamics for lake eutrophication control abstract to succeed in combating lake eutrophication cooperation of local inhabitants small factories and farmers in reducing phosphorus discharge is very important but the willingness of each player to cooperate would depend on the cooperation of other players and on the level of environmental concern of the society in general here we study the integrated dynamics of people s choice of behavior and the magnitude of eutrophication assumptions are there are a number of players who choose between alternative options a cooperative and environment oriented option is more costly than the other the decision of each player is affected by social pressure as well as by economical cost of the options the lake pollution increases with the total phosphorus released and a high pollution level in the lake would enhance the social pressure the model includes a positive and a negative feedback loops which create diverse dynamical behavior the model often shows bistability having an equilibrium with a high level of cooperation among people and clean water and the other equilibrium with low cooperation and polluted water which are simultaneously stable the model also shows fluctuation between a high and a low levels of cooperation in alternating years cycle with a longer periodicity or chaotic fluctuation conservatism of people stabilizes the system and sometimes helps maintaining cooperation the system may show unexpected parameter dependence the improved phosphorus removing efficiency might make water more polluted if it causes the decline in the environmental concern and cooperation among people

contractual difficulties in environmental management the case of wetland mitigation banking abstract this paper offers a principal agent model of private contracting in mitigation banking aimed at protection of wetland acreage and habitat bio diversity and physical functions of us wetlands while it is straightforward to design an incentive contract such a contract may be incapable of achieving the federally mandated objective of no net loss of wetland functions through wetland mitigation there may be failure of contract design or execution also considered are several institutional mechanisms that may promote the convergence of private contracting and attainment mandated wetland protection these include greater oversight by the government payment of subsidies greater accuracy in the identification of actual wetland quality by the principal and use of several other incentive alignment mechanisms

restoring wetlands through wetlands mitigation banks this paper offers the first economic analysis of wetlands mitigation banks the banks are a new alternative for restoration of wetlands by developers before receiving regulatory approval for future development of wetlands in the same watershed a stochastic optimal control model is developed which incorporates ecological uncertainty of wetlands restoration the model helps in examining the decisions of how much to invest in a wetlands mitigation bank the model is calibrated with data from california bioeconomic parameters numerical simulation of the model provides a sensitivity analysis of how model parameters of restoration costs stochastic biological growth interest rate and the market value of credits affect the trajectory of investment and the optimal stopping state of wetlands quality when the investment ends the analysis reveals that restoration of the whole site will occur when there is a reduction in restoration costs an increase in biological uncertainty or an increase in the value of wetlands credits continued restoration is harder to justify with a higher interest rate

the diffusion of computers and the distribution of wages abstract when the costs are decreasing workers adopt technology at the point where the costs equal the increased productivity output per worker increases immediately while productivity benefits increase only gradually if costs continue to fall as a result workers in computer adopting labor market groups experience an immediate fall in wages due to increased supply on the other hand adopting workers experience wage increases with some delay this model explains why increased computer use does not immediately lead to higher wage inequality more specifically the results of the model are shown to be consistent with the question why within group wage inequality among skilled workers as a result of computer technology adoption in the united states increased in the 1970s while between group wage inequality and within group wage inequality among the unskilled did not start to increase until the 1980s the model also predicts that the more compressed german wage structure leads to a lagged diffusion of computer technology along with smaller changes in wage inequality our empirical analysis suggests that this is consistent with the actual developments in germany since the 1980s finally the theoretical predictions seem to be of the right magnitude to explain the empirical quantities observed in the data

the impact of advanced technology adoption on wage structures evidence from taiwan manufacturing firms we examine the impact of advanced technology adoption on wage and employment structures in taiwan using a survey of manufacturing firms that provides direct information on the use of advanced technologies we find that firms using more advanced technologies pay higher wages to both non production and production workers and employ higher fractions of non production workers controlling for the possible endogeneity of technology adoption suggests that the estimated impact of new technologies on wages is downward biased and that the effect on production workers wages may be minimal

does unmeasured ability explain the higher wages of new technology workers abstract we study the impact on new technologies nt on wages using a unique data set that matches data on individuals and on their firms in his important article on the same topic krueger 1993 did not give a definitive answer to the following question if workers who use nt are better paid is it because they are abler or because nt increases their productivity we try to provide a precise answer to this question comparing cross section estimates firm effect estimates and person effect estimates we show that computer based new technologies are used by abler workers these workers appear to become more productive when they get more experienced with these nt in terms of wage differentials the introduction of computer based nt contributes to the increase but less than supposed before each year experience with computer based nt adds around 1 to the wage of workers using such techniques

the evolution of social norms in common property resource use the problem of extracting commonly owned renewable resources is examined within an evolutionary game theoretic framework it is shown that cooperative behavior guided by norms of restraint and punishment may be stable in a well defined sense against invasion by narrowly self interested behavior the resource stock dynamics are integrated with the evolutionary game dynamics effects of changes in prices technology and social cohesion on extraction behavior and the long run stock are analyzed when threshold values of the parameters are crossed social norms can break down leading generally to the lowering of the long run stock and possibly to its extinction copyright 1996 by american economic association