732 resultados para changement de paradigme
Resumo:
The model studies information sharing and the stability of cooperation in cost reducing Research Joint Ventures (RJVs). In a four-stage game-theoretic framework, firms decide on participation in a RJV, information sharing, R&D expenditures, and output. An important feature of the model is that voluntary information sharing between cooperating firms increases information leakage from the RJV to outsiders. It is found that it is the spillover from the RJV to outsiders which determines the decision of insiders whether to share information, while it is the spillover affecting all firms which determines the level of information sharing within the RJV. RJVs representing a larger portion of firms in the industry are more likely to share information. It is also found that when sharing information is costless, firms never choose intermediate levels of information sharing : they share all the information or none at all. The size of the RJV is found to depend on three effects : a coordination effect, an information sharing effect, and a competition effect. Depending on the relative magnitudes of these effects, the size of the RJV may increase or decrease with spillovers. The effect of information sharing on the profitability of firms as well as on welfare is studied.
Resumo:
Evidence of falling wages in Catholic cities and rising wages in Protestant cities between 1500 and 1750, during the spread of literacy in the vernacular, is inconsistent with most theoretical models of economic growth. In The Protestant Ethic, Weber suggested an alternative explanation based on culture. Here, a theoretical model confirms that a small change in the subjective cost of cooperating with strangers can generate a profound transformation in trading networks. In explaining urban growth in early-modern Europe, specifications compatible with human-capital versions of the neoclassical model and endogenous-growth theory are rejected in favor of a “small-world” formulation based on the Weber thesis.
Resumo:
La présente étude analyse les effets dynamiques de la dévaluation du franc CFA, à l’aide d’un modèle monétaire d’équilibre général, intertemporel et multisectoriel. L’accent est particulièrement mis sur les interactions entre dévaluation et accumulation du capital. Dans le modèle, les effets du changement de parité passent par le marché du travail qui se caractérise par l’inertie du salaire nominal. Les résultats montrent que la dévaluation relance l’investissement, avec des effets expansionnistes sur l’activité économique. Le choc monétaire n’a eu qu’un impact limité sur les soldes budgétaire et commercial. Une mesure d’accompagnement telle que la réduction des salaires de la fonction publique améliore ces deux soldes mais déclenche un processus récessif.
Resumo:
We study the problem of measuring the uncertainty of CGE (or RBC)-type model simulations associated with parameter uncertainty. We describe two approaches for building confidence sets on model endogenous variables. The first one uses a standard Wald-type statistic. The second approach assumes that a confidence set (sampling or Bayesian) is available for the free parameters, from which confidence sets are derived by a projection technique. The latter has two advantages: first, confidence set validity is not affected by model nonlinearities; second, we can easily build simultaneous confidence intervals for an unlimited number of variables. We study conditions under which these confidence sets take the form of intervals and show they can be implemented using standard methods for solving CGE models. We present an application to a CGE model of the Moroccan economy to study the effects of policy-induced increases of transfers from Moroccan expatriates.
Resumo:
In a recent paper, Bai and Perron (1998) considered theoretical issues related to the limiting distribution of estimators and test statistics in the linear model with multiple structural changes. In this companion paper, we consider practical issues for the empirical applications of the procedures. We first address the problem of estimation of the break dates and present an efficient algorithm to obtain global minimizers of the sum of squared residuals. This algorithm is based on the principle of dynamic programming and requires at most least-squares operations of order O(T 2) for any number of breaks. Our method can be applied to both pure and partial structural-change models. Secondly, we consider the problem of forming confidence intervals for the break dates under various hypotheses about the structure of the data and the errors across segments. Third, we address the issue of testing for structural changes under very general conditions on the data and the errors. Fourth, we address the issue of estimating the number of breaks. We present simulation results pertaining to the behavior of the estimators and tests in finite samples. Finally, a few empirical applications are presented to illustrate the usefulness of the procedures. All methods discussed are implemented in a GAUSS program available upon request for non-profit academic use.
Resumo:
We extend the class of M-tests for a unit root analyzed by Perron and Ng (1996) and Ng and Perron (1997) to the case where a change in the trend function is allowed to occur at an unknown time. These tests M(GLS) adopt the GLS detrending approach of Dufour and King (1991) and Elliott, Rothenberg and Stock (1996) (ERS). Following Perron (1989), we consider two models : one allowing for a change in slope and the other for both a change in intercept and slope. We derive the asymptotic distribution of the tests as well as that of the feasible point optimal tests PT(GLS) suggested by ERS. The asymptotic critical values of the tests are tabulated. Also, we compute the non-centrality parameter used for the local GLS detrending that permits the tests to have 50% asymptotic power at that value. We show that the M(GLS) and PT(GLS) tests have an asymptotic power function close to the power envelope. An extensive simulation study analyzes the size and power in finite samples under various methods to select the truncation lag for the autoregressive spectral density estimator. An empirical application is also provided.
Resumo:
Using data from the National Longitudinal Survey of Youth (NLSY), we re-examine the effect of formal on-the-job training on mobility patterns of young American workers. By employing parametric duration models, we evaluate the economic impact of training on productive time with an employer. Confirming previous studies, we find a positive and statistically significant impact of formal on-the-job training on tenure with the employer providing the training. However, the expected net duration of the time spent in the training program is generally not significantly increased. We proceed to document and analyze intra-sectoral and cross-sectoral mobility patterns in order to infer whether training provides firm-specific, industry-specific, or general human capital. The econometric analysis rejects a sequential model of job separation in favor of a competing risks specification. We find significant evidence for the industry-specificity of training. The probability of sectoral mobility upon job separation decreases with training received in the current industry, whether with the last employer or previous employers, and employment attachment increases with on-the-job training. These results are robust to a number of variations on the base model.
Resumo:
Between 1700 and 1850, per-capita income doubled in Europe while falling in the rest of Eurasia. Neither geography nor economic institutions can explain this sudden divergence. Here the consequences of differences in communications technology are examined. For the first time, there appeared in Europe a combination of a standardized medium (national vernaculars with a phonetic alphabet) and a non-standardized message (competing religious, political and scientific ideas). The result was an unprecedented fall in the cost of combining ideas and burst of productivity-raising innovation. Elsewhere, decreasing standardization of the medium and increasing standardization of the message blocked innovation.
Resumo:
Recent changes in comparative advantage in the largest OECD economies differ significantly from the predictions of Heckscher-Ohlin-Vanek theory. Japan's rising share of OECD machinery exports and the improvement in the comparative advantage of the USA and Germany in heavy industry were accompanied by growing scarcities of the factors used intensively in the favored sector of each country. Here we examine Acemoglu's (1998, 2002) hypothesis that technical change may be directed toward raising the marginal productivity of abundant factors. Testing this hypothesis with 1970-1992 export data from 14 OECD countries, we find evidence that international comparative advantage was reshaped by innovation biased toward the abundant factors in the largest economies.
Resumo:
This paper studies the transition between exchange rate regimes using a Markov chain model with time-varying transition probabilities. The probabilities are parameterized as nonlinear functions of variables suggested by the currency crisis and optimal currency area literature. Results using annual data indicate that inflation, and to a lesser extent, output growth and trade openness help explain the exchange rate regime transition dynamics.
Resumo:
How does openness affect economic development? This question is answered in the context of a dynamic general equilibrium model of the world economy, where countries have technological differences that are both sector-neutral and specific to the investment goods sector. Relative to a benchmark case of trade in credit markets only, consider (i) a complete restriction of trade, and (ii) a full liberalization of trade. The first change decreases the cross-sectional dispersion of incomes only slightly, and produces a relatively small welfare loss. The second change, instead, decreases dispersion by a significant amount, and produces a very large welfare gain.
Resumo:
L’introduction éventuelle, au Québec, de la force exécutoire pour les actes notariés soulève, du point de vue économique, deux questions. La première porte sur les effets prévisibles de cette mesure, notamment sur le marché des services juridiques de rédaction d’actes. Du côté de l’offre, il convient de distinguer selon que l’acte notarié est obligatoire ou facultatif. Du côté de la demande, le changement tendrait à diminuer le coût de réalisation d’un droit. Le gain qui en résulte peut profiter, en partie, aux notaires. L’ampleur de l’effet dépend de la probabilité qu’il faille recourir à l’exécution forcée. L’effet irait dans le sens de réduire le coût du crédit et d’augmenter sa disponibilité. Pour le débiteur, l’engagement deviendrait plus risqué, mais du même coup, lui permettrait de signaler sa « crédibilité ». Les chiffres fournis dans une étude réalisée par le groupe Secor en 1995 font voir une économie plutôt modeste de ces mesures. Pour évaluer l’ampleur du désengorgement prévisible des tribunaux, il faudrait connaître l’importance des procédures essentiellement engagées pour la perception de créances. Au-delà des effets immédiats, les enjeux de cette mesure sont de deux ordres. D’abord, ils soulèvent la question de la justification d’accorder l’avantage comparatif de la force exécutoire aux actes notariés et à eux seuls. Cette question nous conduit à celle du statut d’officier public des notaires, plus précisément aux caractéristiques qui doivent être jugées essentielles pour ce statut. Car si l’on ne peut prêter au notaire une aussi grande confiance qu’au juge, il convient de s’interroger, aux fins de l’exécution forcée, sur les limites à imposer au contenu des actes ayant force exécutoire. Les réponses à ces questions présupposent des données qu’on peut difficilement obtenir autrement que par l’expérience prudente. Les chiffres disponibles permettent de prévoir des économies modestes. L’introduction de la force exécutoire doit s’accompagner de mesures de stricte surveillance, notamment en matière de conflits d’intérêt potentiels.
Resumo:
L’analyse économique du droit met au jour, en faisant appel à des concepts empruntés à la science économique, une rationalité sous-jacente des règles juridiques et les principaux effets prévisibles de leur changement. Elle propose une lecture des règles juridiques qui les juge par leurs effets incitatifs et par les changements de comportement des citoyens en réponse à ces incitations. Elle fournit des éléments pour un jugement éclairé sur les institutions juridiques et sur des réformes proposées. Elle est, de ce fait, un outil précieux pour le législateur et le juge ainsi que pour la doctrine, qu'elle rappelle à sa mission noble de mettre en lumière des fondements du droit et de montrer la voie des adaptations aux réalités nouvelles. En même temps, elle offre aux économistes un outil pour appréhender le droit.
Resumo:
Département de linguistique et de traduction