5,003 research outputs found
The Human Capital-Intensive Firm and Coordination: Redefined Integration and Disintegration
The aim of this paper is to reconsider the link between integration and disintegration. We argue that the conception of this link depends on the way one defines the firm and its coordinating role. We focus on studying the human capital-intensive firm. We explain that coordination by this kind of firms consists in coordinating productive tasks. The role of the firm is to coordinate the specialization of complementary resources and the division of labour. We show that integration and disintegration must be differentiated by the tools they give to the firm to effectively govern productive assets.Specific human capital; coordination; disintegration; integration; boudaries of the firm
Misalignments and Dynamics of Real Exchange Rates in the CFA Franc Zone
In this paper, we analyse currencies' misalignments of the CFA zone countries and the adjustment process of their real effective exchange rates towards their equilibrium level over the period 1985-2007. To this end, we firstly estimate, using panel cointegration techniques, a long term relationship between the real effective exchange rate and economic fundamentals. Secondly, we estimate a panel smooth transition error correction model in order to take into account non linearities in the convergence process of real exchange rates towards their equilibrium level. Two main results emerge from our analysis. Firstly, the real appreciation of effective exchange rates in the CFA zone countries from the 2000s did not translate, in 2007, into a real overvaluation comparable to that occurring before the devaluation of the CFA franc in 1994. However, some countries are exceptions, indicating a strong heterogeneity within the CFA zone. Finally, the convergence process of real effective exchange rates towards their equilibrium level also differs substantially between country groups. These results tend to show the difficulty to apply a single exchange rate policy in the CFA zone and rather call for further coordination and policy harmonization between the countries.CFA zone, misalignments, panel smooth transition model
On convergence of the auxiliary-vector beamformer with rank-deficient covariance matrices
The auxiliary-vector beamformer is an algorithm that generates iteratively a sequence of beamformers which,
under the assumption of a positive definite covariance matrix R, converges to the minimum variance distortionless response beamformer, without resorting to any matrix inversion. In the case where R is rank-deficient, e.g., when R is substituted for the sample covariance matrix and the number of snapshots is less than the number of array elements, the behavior of the AV beamformer is not known theoretically. In this letter, we derive a new convergence result and show that the AV beamformer weights converge when R is rank-deficient, and that the limit belongs to the class of reduced-rank beamformers
Adaptive beamforming for large arrays in satellite communications systems with dispersed coverage
Conventional multibeam satellite communications systems ensure coverage of wide areas through multiple fixed beams where all users inside a beam share the same bandwidth. We consider a new and more flexible system where each user is assigned his own beam, and the users can be very geographically dispersed. This is achieved through the use of a large direct radiating array (DRA) coupled with adaptive beamforming so as to reject interferences and to provide a maximal gain to the user of interest. New fast-converging adaptive beamforming algorithms are presented, which allow to obtain good signal to interference and noise ratio (SINR) with a number of snapshots much lower than the number of antennas in the array. These beamformers are evaluated on reference scenarios
Robust approaches to remote calibration of a transmitting array
We consider the problem of estimating the gains and phases of the RF channels of a M-element transmitting array, based on a calibration procedure where M orthogonal signals are sent through M orthogonal beams and received on a single antenna. The received data vector obeys a linear model of the type y ÂŒ AFg ĂŸ n where A is an unknown complex scalar accounting for propagation loss and g is the vector of unknown complex gains. In order to improve the performance of the least-squares (LS) estimator at low signal to noise ratio (SNR), we propose to exploit knowledge of the nominal value of g, viz g. Towards this end, two approaches are presented. First, a Bayesian approach is advocated where A and g are considered as random variables, with a non-informative prior distribution for A and a Gaussian prior distribution for g. The posterior distributions of the unknown random variables are derived and a Gibbs sampling strategy is presented that enables one to generate samples distributed according to these posterior distributions, leading to the minimum mean-square error (MMSE) estimator. A second approach consists in solving a constrained least-squares problem in which h ÂŒ Ag is constrained to be close to a scaled version of g. This second approach yields a closed-form solution, which amounts to a linear combination of g and the LS estimator. Numerical simulations show that the two new estimators significantly outperform the conventional LS estimator, especially at low SNR
A Kolmogorov-Smirnov type test for shortfall dominance against parametric alternatives
This paper proposes a Kolmogorov-type test for the shortfall order (also known in the literature as the right-spread or excess-wealth order) against parametric alternatives. In the case of the null hypothesis corresponding to the Negative Exponential distribution, this provides a test for the new better than used in expectation (NBUE) property. Such a test is particularly useful in reliability applications as well as duration and income distribution analysis. The theoretical properties of the testing procedure are established. Simulation studies reveal that the test proposed in this paper performs well, even with moderate sample sizes. Applications to real data, namely chief executive officer (CEO) compensation data and flight delay data, illustrate the empirical relevance of the techniques described in this paper.Right-spread order; Excess-wealth order; New better than used in expectation; Bootstrap; Reliability; CEO compensation; Flight delay
The Human Capital-Intensive Firm and Coordination: Redefined Integration and Disintegration
The aim of this paper is to reconsider the link between integration and disintegration. We argue that the conception of this link depends on the way one defines the firm and its coordinating role. We focus on studying the human capital-intensive firm. We explain that coordination by this kind of firms consists in coordinating productive tasks. The role of the firm is to coordinate the specialization of complementary resources and the division of labour. We show that integration and disintegration must be differentiated by the tools they give to the firm to effectively govern productive assets
Firme intensive en capital humain et coordination : vers une redéfinition du rapport entre intégration et dé-intégration
26 pagesThe aim of this paper is to reconsider the link between vertical integration and disintegration which are traditionally opposed in the literature. The conception of integration and disintegration closely depends on the way we define the firm and its role. This paper focuses on human capital-intensive firms. We explain that coordination by this kind of firms is much more a coordination of productive tasks than a coordination of property rights. We argue that the role of the firm isn't to manage the hold-up problem using residual rights of control on physical assets, but to coordinate complementarities between internal and external agents, division of labour and specialization of resources. Therefore, we show that the coordinating role of the firm involves a redefinition of the link between integration and disintegration. We advance that it can not be viewed as the opposition between the two institutional modes of coordination which are hierarchy and market. Integration and disintegration must be differentiated through the tools they provide to the firm in order to govern the productive specialization of its human assets.L'objectif de cet article est de reconsidĂ©rer le rapport de l'intĂ©gration verticale Ă la dĂ©-intĂ©gration verticale, traditionnellement opposĂ©es dans la littĂ©rature. La comprĂ©hension de l'intĂ©gration et de la dĂ©-intĂ©gration dĂ©pend Ă©troitement de la façon dont sont apprĂ©hendĂ©s la nature et le rĂŽle de la firme. Cet article se focalise sur les firmes intensives en capital humain. Le rĂŽle coordinateur de ce type de firmes ne se limite pas Ă gĂ©rer le problĂšme de hold-up Ă partir des droits de contrĂŽle rĂ©siduels sur des actifs physiques. Nous montrons qu'il consiste plus largement Ă coordonner la spĂ©cialisation productive de l'ensemble des partenaires clĂ©s de l'entreprise, qu'ils soient internes ou externes. Dans cette perspective, nous proposons une nouvelle dĂ©finition du lien entre intĂ©gration et dĂ©-intĂ©gration verticale. De notre point de vue, l'intĂ©gration et la dĂ©-intĂ©gration ne sont plus des finalitĂ©s ; elles conservent une portĂ©e instrumentale dans l'activitĂ© de coordination. IntĂ©gration et dĂ©-intĂ©gration doivent ĂȘtre diffĂ©renciĂ©es sur la base des outils qu'elles offrent Ă la firme en vue de gouverner la spĂ©cialisation des actifs humains
Analyse dynamique de la motivation des Ă©lĂšves en dĂ©but de scolaritĂ© obligatoire en fonction de la nature de leurs interactions avec lâenseignant
National audienceLâobjectif gĂ©nĂ©ral de cette recherche est de mieux comprendre lâĂ©volution de la motivation des Ă©lĂšves en dĂ©but de scolaritĂ© obligatoire (cours prĂ©paratoire) tout en interrogeant les facteurs sur lesquels il est possible dâintervenir afin dâinfluencer le niveau de motivation et son Ă©volution au cours de lâannĂ©e, tels que la qualitĂ© de la relation Ă©lĂšves-enseignant. En dĂ©but, milieu et fin dâannĂ©e de cours prĂ©paratoire, 270 Ă©lĂšves de 45 classes ont Ă©tĂ© interrogĂ©s. Des observations collectĂ©es individuellement auprĂšs des Ă©lĂšves, ainsi que 4 cycles dâobservation des pratiques enseignantes sur une Ă©chelle standardisĂ©e, ont permis de mettre en relation ces pratiques avec lâĂ©volution de leur motivation pour la lecture durant une annĂ©e. Les rĂ©sultats montrent que les Ă©lĂšves prĂ©sentent majoritairement une motivation pour la lecture stable et Ă©levĂ©e tout au long de lâannĂ©e, mais que cette tendance moyenne masque des Ă©volutions spĂ©cifiques plus variables, notamment dĂ©croissantes. Il apparait que la qualitĂ© du soutien Ă lâapprentissage fourni aux Ă©lĂšves par lâenseignant augmente la probabilitĂ© des Ă©lĂšves dâappartenir au groupe motivationnel stable et Ă©levĂ©
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