Tax Evasion and Social Interactions

The paper extends the standard tax evasion model by allowing for social interactions. In Manski's (1993) nomenclature, our model takes into account social conformity effects (i.e., endogenous interactions), fairness effects (i.e., exogenous interactions) and sorting effects (i.e., correlated effects). Our model is tested using experimental data. Participants must decide how much income to report given their tax rate and audit probability, and given those faced by the other members of their group as well as their mean reported income. The estimation is based on a two-limit simultaneous tobit with fixed group effects. A unique social equilibrium exists when the model satisfies coherency conditions. In line with Brock and Durlauf (2001b), the intrinsic nonlinearity between individual and group responses is sufficient to identify the model without imposing any exclusion restrictions. Our results are consistent with fairness effects but reject social conformity and correlated effects.social interactions; tax evasion; simultaneous tobit; laboratory experiments

Tax Evasion and Social Interactions

The paper extends the standard tax evasion model by allowing for social interactions. In Manski's (1993) nomenclature, our model takes into account social conformity effects (i.e., endogenous interactions), fairness effects (i.e., exogenous interactions) and sorting effects (i.e., correlated effects). Our model is tested using experimental data. Participants must decide how much income to report given their tax rate and audit probability, and given those faced by the other members of their group as well as their mean reported income. The estimation is based on a two-limit simultaneous tobit with fixed group effects. A unique social equilibrium exists when the model satisfies coherency conditions. In line with Brock and Durlauf (2001b), the intrinsic nonlinearity between individual and group responses is sufficient to identify the model without imposing any exclusion restrictions. Our results are consistent with fairness effects but reject social conformity and correlated effects.laboratory experiments; simultaneous Tobit; social interactions; tax evasion

Tax Evasion and Social Interactions

The paper extends the standard tax evasion model by allowing for social interactions. In Manski's (1993) nomenclature, our model takes into account social conformity effects (i.e., endogenous interactions), fairness effects (i.e., exogenous interactions) and sorting effects (i.e., correlated effects). Our model is tested using experimental data. Participants must decide how much income to report given their tax rate and audit probability, and given those faced by the other members of their group as well as their mean reported income. The estimation is based on a two-limit simultaneous tobit with fixed group effects. A unique social equilibrium exists when the model satisfies coherency conditions. In line with Brock and Durlauf (2001b), the intrinsic nonlinearity between individual and group responses is sufficient to identify the model without imposing any exclusion restrictions. Our results are consistent with fairness effects but reject social conformity and correlated effects.Social interactions, tax evasion, simultaneous tobit, laboratory experiments

Tax Evasion and Social Interactions

The paper extends the standard tax evasion model by allowing for social interactions. In Manski's (1993) nomenclature, our model takes into account endogenous interactions, i.e., social conformity effects, exogenous interactions, i.e., fairness effects, and correlated effects. Our model is tested using experimental data. Participants must decide how much income to report given individual and group tax rates and audit probabilities, and given a feedback on theother members' reporting behavior. Myopic and self-consistent expectations are considered in the analysis. In the latter case, the estimation is based on a two-limit simultaneous tobit with fixed group effects. A unique social equilibrium exists when the model satisfies coherency conditions. In line with Brock and Durlauf (2001b), the intrinsic nonlinearity between individual and group responses helps identify the model. Our results provide evidence of fairness effects but reject social conformity.laboratory experiments; simultaneous Tobit; social interactions; tax evasion

Convergence of a Finite Volume Scheme for a Corrosion Model

In this paper, we study the numerical approximation of a system of partial dif-ferential equations describing the corrosion of an iron based alloy in a nuclear waste repository. In particular, we are interested in the convergence of a numerical scheme consisting in an implicit Euler scheme in time and a Scharfetter-Gummel finite volume scheme in space

The existence of solutions to a corrosion model

AbstractIn this work, we consider a corrosion model of iron based alloy in a nuclear waste repository. It consists of a PDE system, similar to the steady-state drift–diffusion system arising in semiconductor modelling. The main difference lies in the boundary conditions, since they are Robin boundary conditions and imply an additional coupling between the equations. Using a priori estimates for the solution and Schauder’s fixed point theorem, we show the existence of solutions to the corrosion model

Chronologie holocène des feux de forêts et dynamique éolienne pour le secteur de Radisson, Québec nordique

Cette recherche vise à documenter l'évolution de la dynamique éolienne holocène, en relation avec les feux de forêt pour l'Holocène moyen et supérieur en Jamésie. La chronostratigraphie et l'analyse macrofossile des paléosols dunaires combinée à l'analyse pollinique ont permis d'identifier quatre périodes. La période I (6600-4200 ans étal. AA), est caractérisée par l'occurrence des feux ponctuels, la période II (4200-2600 ans étal. AA) est marquée par une fréquence plus élevée de feux et correspond à une phase de densification de la forêt à l'échelle régionale. Durant la période Ul (2600-1600 ans étal. AA), les dépôts éoliens furent probablement soumis à des conditions plus arides. Étant dénudés de végétation, aucun paléosol ni aucun feu n'a été enregistré. La période IV (1600 ans étal. AA - présent) est caractérisée par un retour à une fréquence plus élevée des feux. Les données macrofossiles des paléosols dunaires indiquent que le pin gris fut présent dans cette région dès 6300 ans étal. AA, soit plus de 2000 ans que seules les données polliniques ne le suggèrent

Tax Evasion and Social Interactions

The paper extends the standard tax evasion model by allowing for social interactions. In Manski’s (1993) nomenclature, our model takes into account social conformity effects (i.e., endogenous interactions), fairness effects (i.e., exogenous interactions) and sorting effects (i.e., correlated effects). Our model is tested using experimental data. Participants must decide how much income to report given their tax rate and audit probability, and given those faced by the other members of their group as well as their mean reported income. The estimation is based on a two-limit simultaneous tobit with fixed group effects. A unique social equilibrium exists when the model satisfies coherency conditions. In line with Brock and Durlauf (2001b), the intrinsic nonlinearity between individual and group responses is sufficient to identify the model without imposing any exclusion restrictions. Our results are consistent with fairness effects but reject social conformity and correlated effects. Cet article généralise le modèle standard de fraude fiscale en permettant la présence d’interactions sociales. Suivant la nomenclature de Manski (1993), notre modèle tient compte des effets de conformité sociale (i.e. interactions endogènes), des effets d’équité (i.e. interactions exogènes) et des effets de sélection (i.e. effets corrélés). Le modèle est testé à l’aide de données expérimentales. Les participants doivent choisir le montant déclaré de leur revenu, étant donné leur taux d’impôt, leur probabilité d’être contrôlé par le fisc et étant donné ceux de leur groupe de référence ainsi que le revenu moyen déclaré par ce dernier. L’estimation se fonde sur un modèle tobit simultané à deux bornes avec des effets fixes de groupe. Un équilibre social unique existe lorsque le modèle satisfait des conditions de cohérence. Suivant en cela Brock et Durlauf (2001b), la non-linéarité intrinsèque entre les réponses individuelles et celles du groupe est suffisante pour identifier le modèle sans avoir à imposer des restrictions d’exclusion. Nos résultats sont cohérents avec la présence d’effets d’équité mais rejettent la conformité sociale ainsi que les effets corrélés.social, interactions, tax evasion, simultaneous tobit, laboratory experiments., interactions sociales, fraude fiscale, tobit simultané, économie expérimentale

On the existence of solutions for a drift-diffusion system arising in corrosion modelling

International audienceIn this paper, we consider a drift-diffusion system describing the corrosion of an iron based alloy in a nuclear waste repository. In comparison with the classical drift-diffusion system arising in the modeling of semiconductor devices, the originality of the corrosion model lies in the boundary conditions which are of Robin type and induce an additional coupling between the equations. We prove the existence of a weak solution by passing to the limit on a sequence of approximate solutions given by a semi-discretization in time

First question. Reports on the brief of Ms. Monique Mund-Dopchie. Commissioners' reports.

Rapport du mémoire de Mme Monique Mund-Dopchie sur l'artiste grec Eschyle en 1979. Les membres du jury sont Claire Préaux, Jules Labarbe et Léon Lacroix.Report on the memoir of Mrs Monique Mund-Dopchie on the Greek artist Aeschylus in 1979. The members of the jury were Claire Préaux, Jules Labarbe and Léon Lacroix