1,990 research outputs found
Full robustness to outliers in a Bayesian location-scale model
The use of heavy-tailed distributions is a valuable tool in developing robust Bayesian procedures, limiting the influence of outliers on posterior inference. In this paper, the behavior of the posterior density for a location-scale model is investigated when the sample contains outliers. L-exponentially varying functions are introduced in order to characterize the tails of the densities. Simple conditions on the tails of the likelihood, using L-exponentially varying functions, are established to determine the proportion of observations that can be rejected as outliers. It is shown that the posterior distribution converges in law to the posterior that would be obtained from the reduced sample, excluding the outliers, as they tend to plus or minus infinity, at any given rate
Robustness to outliers in location-scale parameter model using log-regularly varying distributions
Estimating the location and scale parameters is common in statistics, using,
for instance, the well-known sample mean and standard deviation. However,
inference can be contaminated by the presence of outliers if modeling is done
with light-tailed distributions such as the normal distribution. In this paper,
we study robustness to outliers in location-scale parameter models using both
the Bayesian and frequentist approaches. We find sufficient conditions (e.g.,
on tail behavior of the model) to obtain whole robustness to outliers, in the
sense that the impact of the outliers gradually decreases to nothing as the
conflict grows infinitely. To this end, we introduce the family of
log-Pareto-tailed symmetric distributions that belongs to the larger family of
log-regularly varying distributions.Comment: Published at http://dx.doi.org/10.1214/15-AOS1316 in the Annals of
Statistics (http://www.imstat.org/aos/) by the Institute of Mathematical
Statistics (http://www.imstat.org
Polluters and Abaters
To comply with laws, regulations and social demands, polluting firms increasingly purchase the needed means from specialized suppliers. This paper analyzes this relatively recent phenomenon. We show how environmental regulation, the size of the output market, the elasticity of demand for abatement goods and services, and the fact that in-house and outsourced abatement expenses are substitutes or complements can influence a polluterâs make-or-buy decision. Specific features of abatement outsourcing are highlighted, qualifications and refinements of the theory of vertical integration are then proposed, and some consequences for environmental policy are briefly discussed.Eco-industry, Make-or-buy Decision, Outsourcing, Vertical Integration
Environmental Risk Management and the Business Firm
This chapter considers three matters that business firms whose activities can be dangerous for human health and the environment increasingly have to deal with: public disclosure of all health and environmental risks, direct involvement of stakeholders in the management of operations, and integration of health and environmental risk management with the management of other business risks. It summarizes recent managerial economics research on those matters and suggests some promising research areas. Ce chapitre considÚre trois questions qui préoccupent de plus en plus les firmes dont les activités font peser certains risques sur la santé humaine et l'environnement, soit la révélation au public de ces risques, l'implication directe de parties externes (assureurs, banquiers, représentants du public, etc.) dans la gestion des opérations, voire la planification stratégique, et la gestion intégrée de tous les risques d'affaires. On résume les récentes percées de l'économie managériale sur ces sujets, et l'on indique certaines pistes de recherche particuliÚrement prometteuses.Environmental risk disclosures, extended liability, integrated risk management, Bilan environnemental, responsabilité étendue, gestion intégrée des risques
Remarks on Environmental Regulation, Firm Behavior and Innovation
The Porter Hypothesis says that well-designed environmental regulation should trigger innovations and enhance the competitiveness of firms. This paper, which follows the invitation to participate at a recent workshop financed by the Environmental Protection Agency in Washington, summarizes theoretical findings concerning this Hypothesis and makes recommendations to improve existing regulation. L'hypothĂšse de Porter veut qu'une rĂ©glementation environnementale bien conçue encourage l'innovation et renforce la compĂ©titivitĂ© des entreprises. Ce cahier, qui fait suite Ă l'invitation Ă participer Ă un rĂ©cent atelier financĂ© par la Environmental Protection Agency des Ătats-Unis, rĂ©sume la recherche thĂ©orique rĂ©cente se rapportant Ă la validitĂ© de cette hypothĂšse et formule des recommandations visant Ă amĂ©liorer les rĂ©glements existants.Environmental regulation, innovation, organizational failure, RĂ©glementation environnementale, innovation, failles organisationnelles
Corporate Strategies For Managing Environmental Risk (The International Library Of Environmental Economics And Policy â Volume xx)
This paper is the introduction to a forthcoming anthology (published by Ashgate) of economic contributions to the subject. It ties the articles together, starting with a primer on corporate strategy, then considering corporate environmental strategy, and concluding on implementation issues. Cet article est en fait l'introduction d'une anthologie (à paraßtre chez Ashgate) de contributions marquantes de l'analyse économique aux stratégies environnementales corporatives. On vise donc à intégrer les articles retenus autour de trois pÎles : la stratégie corporative, la stratégie environnementale, et les questions de mise en oeuvre.economics of strategy, environmental economics, implementation of strategy, économie de la stratégie d'entreprise, économie de l'environnement, implantation de la stratégie
Polluters and Abaters
To comply with laws, regulations and social demands, polluting firms increasingly purchase the needed means from specialized suppliers. This paper an- alyzes this relatively recent phenomenon. We show how environmental regulation, the size of the output market, the elasticity of demand for abatement goods and services, and the fact that in-house and outsourced abatement expenses are substitutes or complements can influence a polluter's make-or-buy decision. Specific features of abatement outsourcing are highlighted, qualifications and refinements of the theory of vertical integration are then proposed, and some consequences for environmental policy are briefly discussed.
The Pigouvian Tax Rule in the Presence of an Eco-Industry
Les biens et services de dépollution sont actuellement le plus souvent livrés par une éco-industrie. Cette note reconsidÚre la taxe pigouvienne dans ce contexte. On montre qu'une taxe optimale sur les émissions polluantes se démarquera du coût social marginal de la pollution en fonction des pouvoirs de marché relatifs des pollueurs et des firmes environnementales.
The Pigouvian Tax Rule in the Presence of an Eco-Industry
Pollution abatement goods and services are now largely being delivered by a specialized âeco-industry.â This note reconsiders Pigouvian taxes in this context. We find that the optimal emission tax will depart from the marginal social cost of pollution according to the pollutersâ and the environment firmsâ relative market power.Pigouvian taxes, Environment industry
Incentives in Common Agency
This paper considers situations where an agent must allocate his nonobservable effort among several tasks and where several principals hold diverging viewpoints on what the best allocation should be. Economic theory currently sees each of these features as major obstacles to raising the strength of an agent s incentives. This paper proposes a simple scheme - based on contingent monitoring - that can nevertheless mitigate both of these obstacles simultaneously. Under this scheme, if the agent s absolute risk aversion decreases fast enough with respect to wealth, then the principals would coordinate their respective incentive provision so that the agent would also see his various tasks as complementary (instead of substitute) income-enhancing activities. Furthermore, coordination could be achieved in a somewhat liberal or decentralized way, in the sense that some principals would need to control only the tasks they have assigned to the agent. Potential applications to corporate compliance, the organization of government, and the management of innovation are briefly discussed. Nous Ă©tudions les situations oĂč (1) un agent doit distribuer ses efforts (qui ne peuvent ĂȘtre observĂ©s par des tiers) sur diffĂ©rentes tĂąches et oĂč (2) plusieurs parties prenantes ont des points de vue divergents quant Ă la distribution la plus souhaitable. La thĂ©orie Ă©conomique prĂ©dit actuellement que chacun de ces ingrĂ©dients la prĂ©sence de tĂąches multiples et la concurrence entre parties prenantes -suffit Ă lui seul Ă abaisser considĂ©rablement la puissance des incitations. Ce papier propose nĂ©anmoins un remĂšde simple, via l utilisation d audits contingents. Le mĂ©canisme proposĂ© rendrait en effet les tĂąches complĂ©mentaires du point de vue de l agent ; en mĂȘme temps, les parties prenantes parviendraient Ă se coordonner pour le mettre en oeuvre, Ă condition que l aversion au risque de l agent dĂ©croisse suffisamment vite avec l augmentation de sa richesse. Cette coordination pourrait par ailleurs se rĂ©aliser d une maniĂšre «libĂ©rale», en ce sens que certaines parties prenantes n auraient besoin de contrĂŽler que les tĂąches les intĂ©ressant directement. Certaines utilisations possibles du mĂ©canisme pour les rĂ©gimes de conformitĂ© des entreprises, l organisation des gouvernements, et le management de l innovation sont briĂšvement esquissĂ©es., nous trouvons des changements dans la dynamique et dans la mĂ©moire longue de la volatilitĂ©.Multitasking, several principals, upper-tail audits, Principal-agent, multi-tĂąches, plusieurs principaux, audits
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