The effect of firm-level contracts on the structure of wages: evidence from matched employer-employee data

Revised: 2006-11

MPI parallel programming of mixed integer optimization problems using CPLEX with COIN-OR

The aim of this technical report is to present some detailed explanations in order to help to understand and use the Message Passing Interface (MPI) parallel programming for solving several mixed integer optimization problems. We have developed a C++ experimental code that uses the IBM ILOG CPLEX optimizer within the COmputational INfrastructure for Operations Research (COIN-OR) and MPI parallel computing for solving the optimization models under UNIX-like systems. The computational experience illustrates how can we solve 44 optimization problems which are asymmetric with respect to the number of integer and continuous variables and the number of constraints. We also report a comparative with the speedup and efficiency of several strategies implemented for some available number of threads.

La inseparabilidad y el grado de adaptación como determinantes de la internacionalización de las empresas de servicios

[ES] La mayor parte de enfoques teóricos de internacionalización han surgido en el marco del sector industrial y, por tanto, algunas explicaciones podrían no ser generalizables al sector servicios en su globalidad. Por ello, las características sectoriales deben ser tenidas en cuenta en el análisis de los modos de entrada de las empresas de servicios, ya que es posible encontrar patrones de comportamiento muy diferentes no sólo con respecto a las empresas industriales sino también entre las propias empresas de servicios.

Evolución y tendencias de la marca de distribuidor en los mercados de gran consumo: el caso de España

[ES] La marca de distribuidor está experimentando un proceso de crecimiento notable en nuestro país, especialmente en los mercados de productos de gran consumo. Sobre este particular, este trabajo tiene por objeto analizar la situación actual así como las tendencias futuras en la comercialización de marcas de distribuidor en la industria de productos de gran consumo. Para ello, se tendrá en cuenta la penetración de las marcas de distribuidor en distintas categorías de productos de gran consumo, exponiéndose una serie de argumentos con objeto de explicar las tendencias observadas.

Elementu anaforikoak eskolako testuetan

[EU]Artikulu honetan, eskolan eukeraz erabiltzen diren azalpenezko testu idatziaetan agetzen diren elementu anaforikoak aztertzen ditu egileak. Natur Zientzietako hiru testuliburetako unitate didaktiko batean erabilitako azalpenak aztertu ondoren, multzo bakoitzean ikusitako ezaugarri nagusienak eta bien artean dauden zenbait ezberdintasuni buruzko hausnarketak bildu dira lan honetan

The interactive brain hypothesis

Enactive approaches foreground the role of interpersonal interaction in explanations of social understanding. This motivates, in combination with a recent interest in neuroscientific studies involving actual interactions, the question of how interactive processes relate to neural mechanisms involved in social understanding. We introduce the Interactive Brain Hypothesis (IBH) in order to help map the spectrum of possible relations between social interaction and neural processes. The hypothesis states that interactive experience and skills play enabling roles in both the development and current function of social brain mechanisms, even in cases where social understanding happens in the absence of immediate interaction. We examine the plausibility of this hypothesis against developmental and neurobiological evidence and contrast it with the widespread assumption that mindreading is crucial to all social cognition. We describe the elements of social interaction that bear most directly on this hypothesis and discuss the empirical possibilities open to social neuroscience. We propose that the link between coordination dynamics and social understanding can be best grasped by studying transitions between states of coordination. These transitions form part of the self-organization of interaction processes that characterize the dynamics of social engagement. The patterns and synergies of this self-organization help explain how individuals understand each other. Various possibilities for role-taking emerge during interaction, determining a spectrum of participation. This view contrasts sharply with the observational stance that has guided research in social neuroscience until recently. We also introduce the concept of readiness to interact to describe the practices and dispositions that are summoned in situations of social significance (even if not interactive). This latter idea links interactive factors to more classical observational scenarios.

Somatisation in primary care: experiences of primary care physicians involved in a training program and in a randomised controlled trial

Background: A new intervention aimed at managing patients with medically unexplained symptoms (MUS) based on a specific set of communication techniques was developed, and tested in a cluster randomised clinical trial. Due to the modest results obtained and in order to improve our intervention we need to know the GPs' attitudes towards patients with MUS, their experience, expectations and the utility of the communication techniques we proposed and the feasibility of implementing them. Physicians who took part in 2 different training programs and in a randomised controlled trial (RCT) for patients with MUS were questioned to ascertain the reasons for the doctors' participation in the trial and the attitudes, experiences and expectations of GPs about the intervention. Methods: A qualitative study based on four focus groups with GPs who took part in a RCT. A content analysis was carried out. Results: Following the RCT patients are perceived as true suffering persons, and the relationship with them has improved in GPs of both groups. GPs mostly valued the fact that it is highly structured, that it made possible a more comfortable relationship and that it could be applied to a broad spectrum of patients with psychosocial problems. Nevertheless, all participants consider that change in patients is necessary; GPs in the intervention group remarked that that is extremely difficult to achieve. Conclusion: GPs positively evaluate the communication techniques and the interventions that help in understanding patient suffering, and express the enormous difficulties in handling change in patients. These findings provide information on the direction in which efforts for improving intervention should be directed.

Is inbreeding avoidance driving female mate choice in Verreaux's sifaka lemurs?

Females of different species might exert female mate choice for different reasons, one of them the aim of avoiding inbreeding. In this study I examine the implication of inbreeding avoidance as a mechanism driving female mate choice in Verreaux’s sifaka lemurs (Propithecus verreauxi). In fact, in this species females are dominant and appear to be able to choose certain males to mate with, while observations indicate that rank, body size, canine size and proportions of fights won are not factors influencing female mate choice. So I hypothesized that females mate choice is driven by inbreeding avoidance in Verreaux’s sifaka lemurs. Tissue and fecal samples were collected in the Kirindy Mitea National Park in western Madagascar as a source of DNA. Parentage was assigned for a sample of the population and relatedness coefficients between dams and sires were estimated and compared to those of between random female and male pairs, dams and other candidate sires within the population and within the groups were the offspring were conceived. I found that there were no significant differences in none of the comparisons which means that Verreaux’s sifaka females do not mate more with males that are more distantly related to them. I concluded that inbreeding avoidance does not appear to be the main force driving female mate choice in Verreaux’s sifaka lemurs and I addressed explanations for these findings. With this study I contribute to our knowledge of female mate choice in lemurs.

Self-Organized Criticality, Plasticity and Sensorimotor Coupling. Explorations with a Neurorobotic Model in a Behavioural Preference Task

During the last two decades, analysis of 1/f noise in cognitive science has led to a considerable progress in the way we understand the organization of our mental life. However, there is still a lack of specific models providing explanations of how 1/f noise is generated in coupled brain-body-environment systems, since existing models and experiments typically target either externally observable behaviour or isolated neuronal systems but do not address the interplay between neuronal mechanisms and sensorimotor dynamics. We present a conceptual model of a minimal neurorobotic agent solving a behavioural task that makes it possible to relate mechanistic (neurodynamic) and behavioural levels of description. The model consists of a simulated robot controlled by a network of Kuramoto oscillators with homeostatic plasticity and the ability to develop behavioural preferences mediated by sensorimotor patterns. With only three oscillators, this simple model displays self-organized criticality in the form of robust 1/f noise and a wide multifractal spectrum. We show that the emergence of self-organized criticality and 1/f noise in our model is the result of three simultaneous conditions: a) non-linear interaction dynamics capable of generating stable collective patterns, b) internal plastic mechanisms modulating the sensorimotor flows, and c) strong sensorimotor coupling with the environment that induces transient metastable neurodynamic regimes. We carry out a number of experiments to show that both synaptic plasticity and strong sensorimotor coupling play a necessary role, as constituents of self-organized criticality, in the generation of 1/f noise. The experiments also shown to be useful to test the robustness of 1/f scaling comparing the results of different techniques. We finally discuss the role of conceptual models as mediators between nomothetic and mechanistic models and how they can inform future experimental research where self-organized critically includes sensorimotor coupling among the essential interaction-dominant process giving rise to 1/f noise.

La oposición estructural «copulativas/disyuntivas» en los gramáticos latinos

[EN] Generally the opinion about Latin grammarians ist that only transmited the theories of Greeks without important contributions. This paper, in which we analyse their explanations of copulative and disjuntive conjuntions, tries to prove that it is necessary to change this mind, because the majority of Latin grammarians not only made a more elaborare and coherent doctrinal corpus than the Greeks, but also these theories might connect, "salvatis salvandis", with the modern structural Linguistic.

Irlandés antiguo "·berar", umbro "ferar" y las desinencias medias indoeuropeas de tercera persona

[ES] Este trabajo se dedica fundamentalmente a revisar la interpretación usual de los tipos irlandés antiguo "·berar" y umbro "ferar" como provenientes de una forma originaria que es caracterizada por lo común como 3.ª sg. con desinencia medio-pasiva sin dental. Con este fin, se analizan las hipótesis hasta ahora propuestas, tanto en su vertiente formal como semántica (§§4-6), se valoran otras posibles explicaciones para formas de otras lenguas indoeuropeas que han sido aducidas como apoyo para tal reconstrucción (§§7-9) y, por último, se propone que el tipo irl.a. "·berar" es producto de una innovación céltica (insular) (§§10-19) y que no hay desinencias en "-r" sin dental en itálico (§§20-25).