Expertise or Experience: What Raises Pay?

An equilibrium job search model with on-the-job-search is presented and solved, in which we allow firms to implement optimal wage posting strategies in the sense that they leave no rent to their employees and counter the offers received by their employees from competing firms. Cross-firm productivity dispersion arises endogenously in equilibrium. The model delivers a hump-shaped aggregate earnings distribution that reflects both firm- and worker-heterogeneity. The model also generates plausible individual career paths on the basis of which it is estimated, using a French panel of wages over the period 1994-96.

Equilibrium Wage Dispersion with Worker and Employer Heterogeneity

We consider an equilibrium search model with on-the-job search where Þrms set wages. If employers are perfectly aware of all workers job opportunities, then when an employee receives an outside job offer, it is optimal for their employer to try to retain them by matching the offer, so long as the resulting wage doesn’t exceed the worker.s productivity. A Bertrand competition is thus triggered between the incumbent employer and the.poacher., which results in a wage increase for the worker. However, if workers are able to vary their search intensity, then this offer-matching policy runs into a moral hazard problem. Knowing that outside offers lead to wage increases, workers are induced to search more intensively, which is costly for the Þrms. Assuming that Þrms can commit never to match outside offers, we examine the set of Þrm types for which it is preferable to do so. We derive sufficient conditions for the equilibrium to be of the sort all Þrms match or no Þrm matches. Finally, computed examples show that, even though virtually any situation can be observed in equilibrium when the sufficient conditions are not met, a plausible pattern is one where a dual labor market emerges, with bad jobs at low-porductivity, nomatching arms and good jobs at high-poductiviy, matching arms

Wage bargaining with on-the-job search: theory and evidence

Most applications of Nash bargaining over wages ignore between-employer competition for labor services and attribute all of the workers' rent to their bargaining power. In this paper, we write and estimate an equilibrium model with strategic wage bargaining and on-the-job search and use it to take another look at the determinants of wages in France. There are three essential determinants of wages in our model: productivity, competition between employers resulting from on-the-job search, and the workers' bargaining power. We find that between-firm competition matters a lot in the determination of wages, because it is quantitatively more important than wage bargaining à la Nash in raising wages above the workers' "reservation wages," defined as out-of-work income. In particular, we detect no significant bargaining power for intermediate- and low-skilled workers, and a modestly positive bargaining power for high-skilled workers

Tenure, Experience, Human Capital and Wages:A Tractable Equilibrium Search Model of Wage Dynamics

We develop and estimate an equilibrium job search model of worker careers, allowing for human capital accumulation, employer heterogeneity and individual-level shocks. Wage growth is decomposed into contributions of human capital and job search, within and between jobs. Human capital accumulation is largest for highly educated workers. The contribution from job search to wage growth, both within- and between-job, declines over the first ten years of a career – the ‘job-shopping’ phase of a working life – after which workers settle into high-quality jobs using outside offers to generate gradual wage increases, thus reaping the benefits from competition between employers

In silico-in vitro screening of protein-protein interactions: towards the next generation of therapeutics.

International audienceProtein-protein interactions (PPIs) have a pivotal role in many biological processes suggesting that targeting macromolecular complexes will open new avenues for the design of the next generation of therapeutics. A wide range of "in silico methods" can be used to facilitate the design of protein-protein modulators. Among these methods, virtual ligand screening, protein-protein docking, structural predictions and druggable pocket predictions have become established techniques for hit discovery and optimization. In this review, we first summarize some key data about protein-protein interfaces and introduce some recently reported computer methods pertaining to the field. URLs for several recent free packages or servers are also provided. Then, we discuss four studies aiming at developing PPI modulators through the combination of in silico and in vitro screening experiments

Development of an injectable composite for bone regeneration

With the development of minimally invasive surgical techniques, there is a growing interest in the research and development of injectable biomaterials especially for orthopedic applications. In a view to enhance the overall surgery benefits for the patient, the BIOSINJECT project aims at preparing a new generation of mineral-organic composites for bone regeneration exhibiting bioactivity, therapeutic activity and easiness of use to broaden the application domains of the actual bone mineral cements and propose an alternative strategy with regard to their poor resorbability, injectability difficulties and risk of infection. First, a physical-chemical study demonstrated the feasibility of self-setting injectable composites associating calcium carbonate-calcium phosphate cement and polysaccharides (tailor-made or commercial polymer) in the presence or not of an antibacterial agent within the composite formulation. Then, bone cell response and antimicrobial activity of the composite have been evaluated in vitro. Finally, in order to evaluate resorption rate and bone tissue response an animal study has been performed and the histological analysis is still in progress. These multidisciplinary and complementary studies led to promising results in a view of the industrial development of such composite for dental and orthopaedic applications

Le site néolithique final de La Fare (Forcalquier, Alpes-de-Haute-Provence). Résultats 1995-1999 et révision chronoculturelle

Publié initialement : LEMERCIER O., CAULIEZ J., FURESTIER R., MULLER A., BOUVILLE C., CONVERTINI F., GILABERT C., JORDA M., KHEDHAIER R., LAZARD N., LOIRAT D., PELLISSIER M., PROVENZANO N., VERDIN P. (2004) – Le site Néolithique final de La Fare (Forcalquier, Alpes-de-Haute-Provence) résultats 1995-1999 et révision chronoculturelle, in : DARTEVELLE H. (Dir.) : Rencontres Méridionales de Préhistoire Récente, 5e session, Clermont-Ferrand, 2002, Archéologie du sud-ouest, 2004, p. 445-455.Le site de La Fare est un établissement perché sur un grand éperon de la région de Forcalquier (Alpes-de-Haute-Provence). Occupé de la fin de la Préhistoire jusqu'à l'époque contemporaine, il a livré les vestiges de deux occupations du Néolithique final datables du troisième millénaire avant notre ère. La première occupation, attribuée à la charnière quatrième/troisième millénaire (groupes Couronnien, Fraischamp, Ferrières), présente un système d'enceintes complexe et plusieurs grandes structures. La seconde occupation, rattachée au groupe Rhône-Ouvèze montre un habitat ouvert et la présence d'une sépulture individuelle à mobilier campaniforme. Elle peut être datée du milieu du troisième millénaire. Après une première note d'actualité sur les campagnes 1991-1993, présentée lors des premières Rencontres Méridionales de Préhistoire Récente (Valence, 1994), cet article propose une révision chronoculturelle du site alimentée par les résultats des campagnes de fouilles 1995-1999 et les premières études réalisées sur le mobilier

Experimental characterization and numerical modeling of the influence of a proof load on the fatigue resistance of welded structures

The influence of a proof load, or an initial overload, on the fatigue resistance of welded structures is investigated in this study. Arc welded stiffeners made of S355 steel are considered and fatigue-tested in as-welded and proof-loaded conditions. X-ray diffraction analyses are carried out to evaluate the influence of a proof load on the residual stress field. To better understand the role of a proof load on the mechanical fields in the stress concentration zones, a numerical approach based on elasto-plastic finite element analyses is proposed. The methodology includes a non-local multiaxial fatigue criterion, which integrates a strain hardening contribution, that makes it possible to estimate the number of cycles to failure. The comparison between experimental and numerical results indicates that the beneficial effect of a proof load on the fatigue resistance can be mainly attributed to residual stress and strain hardening effects. The final result is a master SN curve adapted to the fatigue design of stiffener structures, tested under different loading conditions