integrating market alternatives into the economic theory of optimal deterrence i introduction standard models of the public enforcement of law are tractable and have yielded numerous useful insights into how penalties ought to be set 1 several features of the legal system however have proven difficult to explain within the canonical framework for example it struggles to explain why sanctions increase in one s criminal history in a simple and intuitive way and the literature to date has proposed no explanation of why necessity can be a defense for some crimes in particular a partial defense furthermore welfare analysis in the standard framework is based on an often unstated assumption that penalties are being used to solve a missing markets problem which implies that some amount of crime is efficient even from a first best standpoint this result appears counterintuitive for many crimes in particular the most heinous crimes such as rape and has been the source of much controversy in the literature in this article we reconcile the standard theory with these facts we focus on the extensively employed assumption that potential criminals face a binary choice they can either attempt to obtain some benefit or good by committing a proscribed act or do nothing we show that adding the option of achieving their ends via legitimate means to the choice set of potential criminals extends the explanatory power of the canonical approach with regards to these problematic issues our approach is theoretically attractive as the idea that criminal activity represents a means by which criminals achieve their objectives is inherent to the rational choice approach to crime it is natural then to suppose that in many instances criminals have the option of attaining their objectives via legitimate voluntary channels furthermore while it is clearly the case that legitimate alternatives exist for some property crimes such as theft we argue that this assumption is reasonable for a wide range of criminal activities under the canonical approach to optimal deterrence any increase in the penalty associated with criminal activity reduces the opportunities for engaging in involuntary or criminal transactions this implies a loss of utility on the part of potential offenders consequently optimal penalties in this setting are ones that induce efficient crimes that is ones for which the benefits to the criminals outweigh the social harm specifically at the optimum sanctions are set so that the potential criminal internalizes the costs of his or her actions much as in the literature examining tort law we show that when potential criminals have the option of achieving their ends through voluntary exchange maximization of a utilitarian welfare function is equivalent to minimizing the costs of crime which consist of the harm to victims plus enforcement costs in the presence of an option for voluntary trade increasing the penalties associated with crime does not necessarily create a loss of utility instead an increase in the criminal sanction serves to shift activity away from criminal activity in favor of voluntary transactions this means that the optimal penalties can and should be set so as to minimize the harm caused by crime indeed and in stark contrast to the canonical framework in the absence of costs to imposing a sanction the optimal penalty would be one which deters all crime the presence of a voluntary alternative therefore suggests a role for the legal system different from the standard torts logic to encourage the use of existing markets however formal or informal they may be over criminal activity the idea that criminal sanctions should be set so as to encourage voluntary trade was first proposed by posner 1985 2 who associates this function with the criminal justice system but the idea has been considered only rarely in the subsequent literature cooter and ulen 2008 also take this view arguing that society is in general better off when goods are acquired through voluntary exchange p

the empirical analysis of the determinants for environmental technological change a research agenda abstract technological change is usually considered a necessary albeit not sufficient condition for a transition to sustainability however the empirical analysis of the determinants to environmental technological change has not received too much attention in the environmental ecological economics literature and many open questions remain in this context based on a careful review of the literature this paper argues that further analysis should address several issues at different levels i e regarding the conceptual framework the thematic scope of the studies some methodological issues and other aspects related to the environmental policy variable first an integrated conceptual framework which takes into account the interplay between relevant variables influencing environmental technological change i e factors internal and external to the firm and characteristics of the environmental technologies and all the stages of this process with a greater emphasis on the invention stage should be developed other aspects should then be tackled including a focus on several themes i e a greater attention to cross sectoral technologies the barriers to different types of environmental technologies the international dimension of environmental technological change and environmental technological change in small and medium size enterprises methodological issues combination of case studies and econometric modelling and several issues related to the environmental policy variable

on the effective use of stigma as a crime deterrent abstract stigma affects convicted offenders if employers reduce their wage current research considers this kind of informal sanctioning as an effective means for reducing crime and proposes its fostering by the government in this article i first show that increasing stigma may even enhance crime while stigma enhances deterrence of an unconvicted offender it may drive a stigmatized ex convict towards recidivism secondly i provide a solution for guaranteeing stigma s effectiveness notably a harsh er punishment for repeat offenders is required finally with the theoretical analysis as a background stigmatization policies pursued in the states switzerland and spain are compared

influencing the influencers a theory of strategic diffusion the growth of the internet and assorted technologies has made it possible to collect and process detailed information on social networks this article investigates how firms and governments can harness the power of social networks to promote their goals we show that the optimal use of social networks leads to higher sales and greater profits however an increase in the level and dispersion of social interaction can increase or decrease the optimal influence strategy and profits of the player depending on the content of the interaction optimal influence strategies will target individuals with low or high connections depending on the content of interaction finally the returns to investing in market research on social networks are greater in more unequal networks

using price distributions to estimate search costs we show how the equilibrium restrictions implied by standard search models can be used to estimate search cost distributions using price data alone we consider both sequential and nonsequential search strategies and develop estimation methodologies that exploit equilibrium restrictions to recover estimates of search cost heterogeneity that are theoretically consistent with the search models we illustrate the method using online prices for several economics and statistics textbooks

public goods in networks this paper considers incentives to provide goods that are non excludable along social or geographic links we find first that networks can lead to specialization in public good provision in every social network there is an equilibrium where some individuals contribute and others free ride in many networks this extreme is the only outcome second specialization can benefit society as a whole this outcome arises when contributors are linked collectively to many agents finally a new link increases access to public goods but reduces individual incentives to contribute hence overall welfare can be higher when there are holes in a network

talking searching and pricing this paper studies a consumers search model with word of mouth communication firms market a homogeneous product and choose prices consumers obtain price information in two ways they can search on their own and they can talk to other consumers in the basic model word of mouth communication is exogenous and the focus is on how the level of word of mouth communication shapes market equilibrium outcomes when search costs are low an intensification in word of mouth communication decreases firms competition the opposite holds when search costs are high the model is then extended to allow for strategic word of mouth communication market equilibria with word of mouth communication have the feature that some consumers acquire information personally while other consumers obtain their information by networking with others a decrease in the costs of word of mouth communication relatively to the costs of searching reduces the fraction of consumers who acquire information personally consequently it decreases firms competition

maximum likelihood estimation of search costs abstract in a recent paper hong and shum 2006 using price distributions to estimate search costs rand journal of economics 37 257 275 present a structural method to estimate search cost distributions we extend their approach to the case of oligopoly and present a new maximum likelihood method to estimate search costs we apply our method to a data set of online prices for different computer memory chips the estimates suggest that the consumer population can be roughly split into two groups which either have quite high or quite low search costs search frictions confer a significant amount of market power to the firms despite more than 20 firms operating in each of the markets we estimate price cost margins to be around 25 the paper also illustrates how the structural method can be employed to simulate the effects of the introduction of a sales tax

can punishment generate specific deterrence without updating analysis of a stated choice scenario this study explores the specific deterrence generated by punishment in the context of regulatory violations with a focus on the distinction between upward revisions to future punishment parameters likelihood and severity and the experience of being penalized in order to avoid the pitfalls of empirically analyzing actual choices made by regulated entities e g measuring entities beliefs regarding the likelihood and size of future penalties our study examines behavior associated with a stated choice scenario presented within a survey distributed to the environmental managers of facilities regulated under the us clean water act this choice of respondents strengthens the external validity of our empirical results based on a variety of statistical methods our empirical results strongly and robustly reject the standard hypothesis that specific deterrence stems solely from upward revisions to punishment parameters while supporting the alternative hypothesis of experiential deterrence whereby facilities focus on recent experiences to shape their compliance behavior

graduated punishments in public good games a host of social situations feature graduated punishments we explain this phenomenon by studying a repeated public good game in which a social planner imperfectly monitors agents to detect shirkers agents cost of contributing is private information and administering punishments is costly a low punishment today imperfectly sorts agents by type only low cost agents contribute the planner uses this information optimally punishing tomorrow s alleged repeat shirkers harsher than rst time shirkers the threat of becoming branded as repeat oender allows the planner to use a very mild punishment for rst time shirkers attenuating the costs associated with administering punishments graduated punishments are consequently socially optimal as long as the population is not too homogeneous

explaining escalating prices and fines a unified approach abstract this paper provides an explanation for escalating prices and fines based on a unified analytical framework that nests monopoly pricing and optimal law enforcement we show that escalation emerges as an optimal outcome if the principal i lacks commitment ability and ii gives less than full weight to agent benefits escalation is driven by decreasing transfers for non active agents rather than increasing transfers for active agents some forward looking agents then strategically delay their activity which drives a wedge between the optimal static transfer and the benefit of an indifferent agent this wedge is the source of escalation

moral hazard and merit rating over time an analysis of optimal intertemporal wage structures a fundamental problem that has been the focus of much work in agency theory has been the design of contracts to provide insurance to risk averse agents and to elicit appropriate levels of effort in the context of insurance the problem is viewed as one of moral hazard whereby the insured agent will reduce the level of his precautions to prevent an accident if he is insured against the adverse outcome in the labor market context the problem is one of providing effective work incentives while at the same time promoting the risk sharing element of contracts the overall structure of the analyses is quite similar whether or not the focus is on the insurance market the labor market or principal agent problems in general for concreteness this paper addresses the labor market incentives problem the labor market problem is complicated by the firm s inability to observe the worker s ability and effort and also by stochastic elements that impede a firm s attempts to make more indirect inferences using output to assess the worker s productivity related efforts this combination of uncertainty and the need to create incentives takes on added importance in the case of workers who are risk averse the presence of risk aversion often mitigates the emphasis the firm can place on incentive creation as there is a desire on the part of workers to have stable income streams complete equalization of one s income level across states to promote insurance will however remove the differential rewards needed to provide an incentive for individuals to expend effort this inevitable tradeoff between the work incentive and insurance function of contracts has been studied in detail for single period contracts the focus of my analysis here will be on how these influences affect the multi peiiod wage structure although there has been research on the multi period incentives problem2 and on the role of moral hazard in multiperiod contexts 3 there is no literature on the optimal design of a merit rating system over

penalty structures and deterrence in a two stage model experimental evidence multiperiod models of criminal enforcement based on the standard economic approach of becker 1968 generally find that the optimal penalty structure is either flat or declining we present the first experimental test of a two stage theoretical model that predicts decreasing penalty structures will yield greater deterrence than increasing penalty structures this prediction is based on the belief that if the penalty for the first offenses is sufficiently low the agent should commit the offense and continue to offend if undetected our results are consistent with the theoretical prediction that decreasing fine structures are more effective at reducing risky behavior jel c91 k42 k10

the fallacy of only the strong survive the effects of extrinsic motivation on the persistence decisions for under performing firms abstract under performing firms persist even though existing theoretical perspectives indicate that they should be selected out of the market building upon threshold theory gimeno j folta t cooper a woo c 1997 survival of the fittest entrepreneurial human capital and the persistence of underperforming firms administrative science quarterly 42 750 783 and using staw s staw b m 1981 the escalation of commitment to a course of action academy of management review 6 4 577 587 theoretical model of commitment to a course of action we explore and test the factors that lead entrepreneurs to persist with under performing firms we found environmental munificence personal investment personal options previous organizational success and perceived collective efficacy impact the decision to persist with an under performing firm in addition extrinsic motivation moderates those relationships this research adds to the growing literature on highly persistent under performing firms and complements and extends threshold theory

consumer search with observational learning this article studies observational learning in a consumer search environment consumers observe the purchasing decision of a predecessor with similar preferences consumers rationally emulate by initiating their search at the firm from which their predecessor purchased free riding on search effort and reacting less to price changes prices are nonmonotone in search costs and may be as low as marginal costs we discuss several extensions and show that the effect of emulation on prices is stronger when i the number of firms increases ii consumers first visits are more elastic with respect to market shares and iii prices are adjusted more frequently

asymmetric price effects of competition when price dispersion is prevalent a relevant question is what happens to the whole distribution of equilibrium prices when the number of firms changes using data from the gasoline market in the netherlands we find first that markets with n competitors have price distributions that first order stochastically dominate the price distributions in markets with n 1 firms second the effect of competition is stronger for the medium to upper percentiles of the price distribution finally consumer gains from competition are larger for relatively well informed consumers to account for these empirical patterns we extend varian s 1980 model by allowing for richer heterogeneity in consumer price information

learning from neighbours when payoffs from different actions are unknown agents use their own past experience as well as the experience of their neighbours to guide their decision making in this paper we develop a general framework to study the relationship between the structure of these neighbourhoods and the process of social learning we show that in a connected society local learning ensures that all agents obtain the same payoffs in the long run thus if actions have different payoffs then all agents choose the same action and social conformism obtains we develop conditions on the distribution of prior beliefs the structure of neighbourhoods and the informativeness of actions under which this action is optimal in particular we identify a property of neighbourhood structures local independencewhich greatly facilitates social learning simulations of the model generate spatial and temporal patterns of adoption that are consistent with empirical work

word of mouth communication and social learning this paper studies the way that word of mouth communication aggregates the information of individual agents we find that the structure of the communication process determines whether all agents end up making identical choices with less communication making this conformity more likely despite the players naive decision rules and the stochastic decision environment word of mouth communication may lead all players to adopt the action that is on average superior these socially efficient outcomes tend to occur when each agent samples only a few others i introduction economic agents must often make decisions without knowing the costs and benefits of the possible choices given the frequency with which such situations arise it is understandable that agents often choose not to perform studies or experiments but instead rely on whatever information they have obtained via casual word of mouth communication reliance on this sort of easily obtained information appears to be common in circumstances ranging from consumers choosing restaurants or auto mechanics to business managers evaluating alternative organizational structures this paper studies two related environments in arguing that individuals reliance on word of mouth communication has interesting implications for their aggregate behavior first motivated by the diffusion of new technologies we consider a choice between two competing products with unequal qualities or payoffs and show that the structure of communication is important in determining whether the population as a whole is likely to learn to use the superior product second we consider a choice between two products or practices that are equally good and ask whether consumers are likely to herd onto a single choice or whether diversity will obtain even in the long run we explore the implications of word of mouth communication in a simple nonstrategic environment there is a large population of identical players each of whom repeatedly chooses between two possible actions each player s payoff is determined by his own

oligopolistic pricing with heterogeneous consumer search abstract a finite number of identical stores sell a homogeneous good to consumers with heterogeneous search costs who search sequentially with perfect recall and without replacement consumers search rules are optimal with respect to the stores pricing strategies and consumers must visit a store to obtain information about its actual price a symmetric nash equilibrium sne always exists the model exhibits a variety of equilibrium behaviors between monopoly pricing and marginal cost pricing the competitiveness of a market depends crucially on the shape of the search cost distribution moreso than on the number of competing firms

a model of optimal fines for repeat offenders abstract this paper analyzes optimal fines in a model in which individuals can commit up to two offenses the fine for the second offense is allowed to differ from the fine for the first offense there are four natural cases in the model defined by assumptions about the gains to individuals from committing the offense in the case fully analyzed it may be optimal to punish repeat offenders more severely than first time offenders in another case it may be optimal to impose less severe penalties on repeat offenders and in the two remaining cases the optimal penalty does not change

oligopolistic pricing with sequential consumer search n identical stores compete by choosing prices for a homogeneous good with constant marginal costs consumers search sequentially with perfect recall for the lowest price one class of consumers called shoppers have zero search costs while all other consumers have a positive search cost c there is a unique symmetric nash equilibrium price distribution with the property that it changes smoothly from marginal cost pricing when all consumers are shoppers and or c 0 and monopoly pricing when no consumers are shoppers remarkably as the number of stores increases the nash equilibrium becomes more monopolistic copyright 1989 by american economic association

i don t want to be green prosocial motivation effects on firm environmental innovation rejection decisions although the political and consumer consciousness has turned increasingly green many firms continue to resist the adoption of environment friendly technological innovations even in the face of higher costs negative health effects and stricter government oversight this article examines how business owners weigh the trade offs associated with environment friendly innovations by examining the role of prosocial motivation in their decision making process we use primary data to overcome a common restriction in studying environmental innovations the scarcity of relevant data to analyze how business owners expectations perceptions and motivations affect innovation in organizational processes and consequently the level of environmental friendliness of their products or services we found that prosocial motivation had a significant negative impact on innovation adoption and that it is expressed differently under high and low levels of customer compatibility possibly because business owners have a larger number of competing social objectives and priorities our results further showed that the innovation s ability to satisfy downstream customer demands has the greatest impact on environment friendly innovation adoption decisions by business owners this study enhances our understanding of how business owners make innovation decisions based on competing business environmental and social objectives and provides a foundation for future research in this area

endogenous network formation in patent contests and its role as a barrier to entry in a setting of r d co opetition we study by using an all pay auction approach how collaboration affects strategic decisions during a patent contest and how the latter influences the possible collaboration network structures the firms can hope to form the all pay auction approach allows us to 1 endogenize both network formation and r d intensities and 2 take heterogeneous and private valuations for patents into account we find that different from previous literature the complete network is not always the only pairwise stable network even and especially if the benefits from cooperating are important interestingly the other possible stable networks all have the realistic property that some firms decide not to participate in the contest thus weak cooperation through network formation can serve as a barrier to entry on the market for innovation we further show that there need not be any network that survives a well known refinement of pairwise stability strong stability which imposes networks to be immune to coalitional deviations

the theory of optimal law enforcement the economic literature on optimal law enforcement is very recent becker s seminal paper on crime and law enforcement dates from 1968 and most papers which are the focus of this survey have been published in the last ten years the core result presented by becker is the following the probability and the severity of punishment deter crime therefore the fine should be maximal since it is a costless transfer whereas the probability of detection and conviction is costly much of the recent work has attempted to show why becker s result may not hold

the stakeholder theory and the common good the theory of the social responsibility of the firm oscillates between two extremes one that reduces the firm s responsibility to the obtainment of the greatest possible profit for its shareholders and another that extends the firm s responsibility to include a wide range of actors with an interest or stake in the firm the stakeholder theory of the social responsibility of business is more appealing from an ethical point of view and yet it lacks a solid foundation that would be acceptable to a variety of schools of thought in this paper i argue that the stakeholder theory could be founded on the concept of the common good first i explain the foundations of the theory of the common good the concept itself how it relates to the individual good and its role in the firm following that i explain how the theory of the common good could be applied to the stakeholder theory finally i draw some conclusions

networks markets and inequality julien gagnon thanks the gates cambridge trust for financial support sanjeev goyal is grateful to the keynes fellowship and the cambridge inet institute for financial support

over incarceration and disenfranchisement this article presents a model wherein law enforcers propose sentences to maximize their likelihood of reelection and shows that elections typically generate over incarceration i e longer than optimal sentences it then studies the effects of disenfranchisement laws which prohibit convicted felons from voting the removal of ex convicts from the pool of eligible voters reduces the pressure politicians may otherwise face to protect the interests of this group and thereby causes the political process to push the sentences for criminal offenses upwards therefore disenfranchisement further widens the gap between the optimal sentence and the equilibrium sentence and thereby exacerbates the problem of over incarceration moreover this result is valid even when voter turnout is negatively correlated with people s criminal tendencies i e when criminals vote less frequently than non criminals

strategic pricing consumer search and the number of firms discover prices there are three distinct price dispersed equilibria characterized by low moderate and high search intensity the effects of an increase in the number of firms on search behaviour expected prices price dispersion and welfare are sensitive i to the equilibrium consumers search intensity and ii to the status quo number of firms for instance when consumers search with low intensity an increase in the number of firms reduces search does not affect expected price leads to greater price dispersion and reduces welfare in contrast when consumers search with high intensity increased competition results in more search and lower prices when the number of competitors in the market is low to begin with but in less search and higher prices when the number of competitors is large duopoly yields identical expected price and price dispersion but higher welfare than an infinite number of firms a question that has received much attention in economic theory is how the number of competitors and market outcomes are related despite the existence of work showing the contrary see e g satterthwaite 1979 rosenthal 1980 the prediction that emerges from a market where firms interact in a cournot fashion has come to dominate economic thought namely that an increase in the number of competitors leads to larger aggregate production lower market price and improved market performance measured in terms of some social welfare criterion ruffin 1971 this paper challenges the generality of this belief by presenting an oligopoly model with consumer search where the equilibrium expected price may be constant increasing or nonmonotonic in the number of firms we present an economy with two types of consumers consumers who search for prices at no cost fully informed and consumers who must pay a fixed search cost for each price quotation they observe less informed 1 all buyers have the same willingness to pay for the good and buy either a single unit or nothing at all on the supply side of the market there are n firms producing a homogeneous good at constant marginal cost we analyse a one shot simultaneous move game firms set prices and consumers decide how many prices to search for at the same moment in time our model is essentially an oligopolistic version of burdett and judd 1983 where some consumers search costlessly in this model consumers search using a fixed sample size search strategy i e they choose the number of prices to observe before receiving any offer nonsequential search is appealing when consumers find it more advantageous to gather price information quickly morgan and manning 1985 this occurs when the search outcome is observed with delay and delay is costly for instance an mba graduate looking for a job 1 the presence in the model of consumers who search costlessly captures the fact that some people have a

redefining innovation eco innovation research and the contribution from ecological economics while innovation processes toward sustainable development eco innovations have received increasing attention during the past years theoretical and methodological approaches to analyze these processes are poorly developed against this background the term eco innovation is introduced in this paper addressing explicitly three kinds of changes towards sustainable development technological social and institutional innovation secondly the potential contribution of neoclassical and co evolutionary approaches from environmental and innovation economics to eco innovation research is discussed three peculiarities of eco innovation are identified the double externality problem the regulatory push pull effect and the increasing importance of social and institutional innovation while the first two are widely ignored in innovation economics the third is at the least not elaborated appropriately the consideration of these peculiarities may help to overcome market failure by establishing a specific eco innovation policy and to avoid a technology bias through a broader understanding of innovation finally perspectives for a specific contribution of ecological economics to eco innovation research are drawn it is argued that methodological pluralism as established in ecological economics would be very beneficial for eco innovation research a theoretical framework integrating elements from both neoclassical and evolutionary approaches should be pursued in order to consider the complexity of factors influencing innovation decisions as well as the specific role of regulatory instruments and the experience gathered in ecological economics integrating ecological social and economic aspects of sustainable development is highly useful for opening up innovation research to social and institutional changes 2000 elsevier science b v all rights reserved

determinants of environmental innovation new evidence from german panel data sources abstract in most cases empirical analyses of environmental innovations based on firm level data relied on surveys for one point in time these surveys allow for the inclusion of many explanatory variables such as different policy instruments or the influence of pressure groups but it is not possible to address the dynamic character of environmental innovations this paper uses two german panel databases the establishment panel of the institute for employment research iab and the mannheim innovation panel mip of the centre for european economic research zew to explore the determinants of environmental innovations the econometric estimations show that the improvement of the technological capabilities knowledge capital by r d triggers environmental innovations environmental regulation environmental management tools and general organizational changes also encourage environmental innovation a result that has also been postulated by the famous porter hypothesis

cutting environmental penalties to protect the environment abstract when pollutants are persistent and the polluter has private information regarding the occurrence of accidental releases and the cost of clean up we show that the penalty regime which most effectively protects the environment will involve penalties which are less than maximal the extent to which these penalties will be less than maximal is interestingly a non monotonic function of the persistence of the hazardous substance being handled with the highest penalties being appropriate in the case of pollutants of medium persistence our analysis complement consisting work which predicts that setting the penalties faced by some classes of violator below their maximal level may be compliance enhancing see for example harrington journal of public economics 1988 37 29 53 greenberg journal of economic theory 1984 32 1 13 kambhu journal of regulatory economics 1989 1 103 114

the informational divide we propose a model of price competition where consumers exogenously differ in the number of prices they compare our model can be interpreted either as a non sequential search model or as a network model of price competition we show that i if consumers who previously just sampled one firm start to compare more prices all types of consumers will expect to pay a lower price and ii if consumers who already sampled more than one price sample even more prices then there exists a threshold the informational divide such that all consumers comparing fewer prices than this threshold will expect to pay a higher price whereas all consumers comparing more prices will expect to pay a lower price than before thus increased search can create a negative externality and it is not necessarily beneficial for all consumers

incentive generating state dependent penalty system the case of income tax evasion abstract penalty systems can very often be looked upon as corrective measures established in order to eliminate or reduce costly externalities generated by optimizing economic agents hence penalties can be viewed as regulatory measures and their efficient structure should be of interest to economists we propose a dynamic incentive generating penalty system which if instituted may reduce at a given cost the generation of undesirable externalities the special case to which we refer is income tax evasion although our scheme should be applicable to any kind of externalities such as pollution of the environment violation of antirust laws and others which are created by repititive actions of economic agents

subgame perfect punishment for repeat offenders i introduction the literature on optimal law enforcement typically assumes that the government can commit to sanction schemes 1 this means the government can use any set of threats to penalize wrongdoers in particular if a crime occurs the government actually sanctions the wrongdoers even though ex post it may have no incentive to do so potential wrongdoers believe that the government will carry out the threat at any cost and therefore do not engage in the act in the first place in this article i give up the assumption that the government can commit to whatever sanction scheme i consider the analysis of optimal sanctions without the possibility to commit important because judges often have a lot of discretion as to the size of the penalty they may for example adjust sanctions to the financial possibilities age education and so on of the wrongdoer accordingly i allow only for sanctions that the government actually wishes to implement should a crime have occurred ruling out full commitment changes the optimal enforcement schemes suppose for example the government does not care about the sanction as is typically assumed in the literature then it will not enforce the penalty if a crime has happened given that there is say a small cost of doing so the rational criminal will anticipate the ex post enforcement behavior of the government therefore she will commit the crime because the threat of being sanctioned is not credible once one drops the commitment assumption the typical deterrence equilibria of the law enforcement literature between potential wrongdoers and the government are based on empty threats in the language of game theory the equilibria are not subgame perfect or time consistent i study the problem of subgame perfect sanctions using the framework of emons 2003 agents may commit a crime twice the act is inefficient the agents are thus to be deterred the agents are wealth constrained so that increasing the fine for the first offense means a reduction in the possible sanction for the second offense and vice versa the agents may follow history dependent strategies that is commit the crime a second time if and only if they were were not apprehended the first time the government seeks to minimize the probability of apprehension ignoring the government s commitment problem it is optimal to set the sanction for the first offense equal to the entire wealth of the agents while the sanction for the second offense equals zero the intuition is as follows a money penalty imposed for the second offense reduces the amount a person can pay for the first offense because the wealth available to pay penalties is assumed to be fixed over the two periods for that reason a higher probability event namely a first offense that is detected will be more effective use of the scarce money penalty resource than a lower probability event namely a second detected offense why is the probability of detection lower for the second rather than for the first crime simply because an agent faces the possibility of being sanctioned for the second crime if and only if he or she has already been sanctioned the first time for further results it is important to note that the optimal probability of apprehension increases with the benefit from the crimes this decreasing sanction scheme raises of course the issue of time consistency will the government really charge the agent the entire wealth when she was apprehended for the first crime knowing that then she will commit the second act for sure isn t it better for the government to renege and charge little for the first act so that the agent still has sufficient wealth to pay a sanction that deters the second crime given that the first act has been committed anyway that way the government can at least deter the second act to study this problem i consider a rent seeking government

dynamic deterrence theory economic theories of deterrence have primarily been built on static models a common and serious shortcoming of the existing dynamic deterrence models is the assumption of a twoperiod structure that ignores recidivism the aims of this paper are to formulate and solve a general dynamic deterrence model that incorporates recidivistic behaviour to explore its implications and to derive some testable predictions the analysis shows how the value and the intensity of engaging in illegal activity change over time highlights the weaknesses of twoperiod deterrence models and compares the deterrent effectiveness of increasing the likelihood of punishment versus the severity of punishment finally the recidivistic model provides a structural foundation for the widely used stochastic process models of crime in operations research and criminology

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

formal and informal job search i develop a model where workers decide how hard to look for a job via formal and informal search channels the intensity of formal search determines an individual s arrival rate of offers the strength of investment in informal search translates into a job contact network in which job offers are transmitted there are two equilibria one with high formal search and one with high informal search the former pareto dominates the latter

evaluating stakeholder theory this paper is the third in a series of four that is directed at understanding and assessing stakeholder theory for the purposes of business ethics it addresses the suitability and viability of the theory rejecting objections of a moral and efficiency sort based respectively on claims about property rights and the economic superiority of the alternative stockholder approach but accepting that implementation problems require limiting both the number of groupings admitted to stakeholder status and the degree of responsibility towards them the conclusion looks forward to the construction of a suitably limited version of the stakeholder approach in a fourth paper drawing upon this one and the previous two

on the informational role of quantities durable goods and consumers word of mouth communication a dynamic incomplete information game is set up to study the introduction of a durable good when consumers can learn its quality from previous buyers high sales today imply fewer potential buyers tomorrow but each buyer will have better information about the good consumers are fully rational and can update their beliefs even when they do not directly receive information in equilibrium no news is bad news a low quality firm follows a fly by night strategy randomizing over the timing of sales a high quality firm spreads out its sales more smoothly solving a stochastic dynamic programming problem copyright 1997 by economics department of the university of pennsylvania and the osaka university institute of social and economic research association