5,362 research outputs found
Do recruiters prefer applicants with similar skills? Evidence from a randomized natural experiment
In this paper we examine the potential existence of a similar-to-me effect in terms of skills
between recruiters and applicants. Using evidence from entry exams to the Spanish Judiciary,
where applicants are randomly assigned across evaluation committees, we find that committee
members tend to be more demanding at those stages where they are more knowledgeable. As
a result, applicants who excel in the same dimensions as recruiters are more likely to be hire
Why do I like people like me?
In many dimensions the ability to assess knowledge depends critically on the observer's
own knowledge of that dimension. Building on this feature, this paper offers both
theoretical and empirical evidence showing that, in those tasks where multidisciplinary
knowledge is required, evaluations exhibit a similar-to-me effect: candidates who excel
in the same dimensions as the evaluator tend to be ranked relatively higher. It is also
shown that, if races or genders differ in their distribution of ability, group discrimination
will arise unless evaluators (i) are well informed about the extent of intergroup
differences and (ii) they may condition their assessments on candidates' group
belonging
Intercalation and dynamics of hydrated Fe2+ in the vermiculites from Santa Olalla and Ojén
Although the intercalation of Fe3+ into layered phyllosicilicates-especially into smectites-attracted much attention in the past two decades, the information about Fe2+ loaded phyllosilicates is sparse. Here we present an investigation of the Fe2+ exchanged vermiculites from Santa Olalla and Ojén (Andalusia, Spain) by means of Mössbauer spectroscopy. The room temperature Mössbauer spectra are very similar to those of the starting compounds (Na forms) except for a decrease of the contribution of structural Fe3+ and a concomitant increase of the contribution of Fe2+ sites, indicating an internal redox process. The extent of this redox reaction is different for the two vermiculites. Thus, the intercalated Fe2+ acts as an electron mediator from the external medium to the structural Fe3+ ions. A new component attributable to intercalated Fe2+ is practically invisible in the room temperature Mössbauer spectra, but increases strongly and continuously during cooling to 4.2 K, where it is the dominant feature of the Mössbauer patterns. At 4.2 K, its quadruple splitting amounts to 3.31 mm/s, which is in excellent agreement with the quadrupole slitting of Fe2+ coordinated to six water molecules in a highly symmetric octahedral arrangement. The strong decrease of the Mössbauer-Lamb factor of this component with increasing temperature indicates a weak bonding of the Fe 2+ in the interlayer space
Energetics and dynamics of H adsorbed in a nanoporous material at low temperature
Molecular hydrogen adsorption in a nanoporous metal organic framework
structure (MOF-74) was studied via van der Waals density-functional
calculations. The primary and secondary binding sites for H were confirmed.
The low-lying rotational and translational energy levels were calculated, based
on the orientation and position dependent potential energy surface at the two
binding sites. A consistent picture is obtained between the calculated
rotational-translational transitions for different H loadings and those
measured by inelastic neutron scattering exciting the singlet to triplet (para
to ortho) transition in H. The H binding energy after zero point energy
correction due to the rotational and translational motions is predicted to be
100 meV in good agreement with the experimental value of 90 meV.Comment: 5 pagers, 4 figures. added reference
A Practical Example for Model-Driven Web Requirements
The number of approaches for Web environments has grown very fast
in the last years: HDM, OOHDM, and WSDM were among the first, and now a
large number can be found in the literature. With the definition of MDA (Model-
Driven Architecture) and the acceptance of MDE (Model-Driven Engineering)
techniques in this environment, some groups are working in the use of metamodels
and transformations to make their approaches more powerful. UWE (UMLBased
Web Engineering) or OOWS (Object-Oriented Web Solutions) are only
some examples. However, there are few real experiences with Web Engineering in
the enterprise environment, and very few real applications of metamodels and
MDE techniques. In this chapter the practical experience of a Web Engineering
approach, NDT, in a big project developed in Andalusia is presented. Besides, it
shows the usability of metamodels in real environments
A Practical Environment to Apply Model-Driven Web Engineering
The application of a model-driven paradigm in the development of Web Systems has yielded very good research
results. Several research groups are defining metamodels, transformations, and tools which offer a suitable environment,
known as model-driven Web engineering (MDWE). However, there are very few practical experiences in real
Web system developments using real development teams. This chapter presents a practical environment of MDWE
based on the use of NDT (navigational development techniques) and Java Web systems, and it provides a practical
evaluation of its application within a real project: specialized Diraya.Ministerio de Educación y Ciencia TIN2007-67843-C06-03Ministerio de Educación y Ciencia TIN2007-30391-
Contrasting chaotic with stochastic dynamics via ordinal transition networks
We introduce a representation space to contrast chaotic with stochastic dynamics. Following the complex network representation of a time series through ordinal pattern transitions, we propose to assign each system a position in a two-dimensional plane defined by the permutation entropy of the network (global network quantifier) and the minimum value of the permutation entropy of the nodes (local network quantifier). The numerical analysis of representative chaotic maps and stochastic systems shows that the proposed approach is able to distinguish linear from non-linear dynamical systems by different planar locations. Additionally, we show that this characterization is robust when observational noise is considered. Experimental applications allow us to validate the numerical findings and to conclude that this approach is useful in practical contexts.We introduce a representation space to contrast chaotic with stochastic dynamics. Following the complex network representation of a time series through ordinal pattern transitions, we propose to assign each system a position in a two-dimensional plane defined by the permutation entropy of the network (global network quantifier) and the minimum value of the permutation entropy of the nodes (local network quantifier). The numerical analysis of representative chaotic maps and stochastic systems shows that the proposed approach is able to distinguish linear from non-linear dynamical systems by different planar locations. Additionally, we show that this characterization is robust when observational noise is considered. Experimental applications allow us to validate the numerical findings and to conclude that this approach is useful in practical contexts.Fil: Olivares, F.. Pontificia Universidad Católica de Valparaíso; ChileFil: Olivares, F.. Pontificia Universidad Católica de Valparaíso; ChileFil: Zanin, M.. Universidad Politécnica de Madrid; EspañaFil: Zanin, M.. Universidad Politécnica de Madrid; EspañaFil: Zunino, Luciano José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Ópticas. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones Ópticas. Universidad Nacional de La Plata. Centro de Investigaciones Ópticas; Argentina. Universidad Nacional de La Plata. Facultad de Ingeniería. Departamento de Ciencias Básicas; ArgentinaFil: Zunino, Luciano José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Ópticas. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones Ópticas. Universidad Nacional de La Plata. Centro de Investigaciones Ópticas; Argentina. Universidad Nacional de La Plata. Facultad de Ingeniería. Departamento de Ciencias Básicas; ArgentinaFil: Pérez, D.G.. Pontificia Universidad Católica de Valparaíso; ChileFil: Pérez, D.G.. Pontificia Universidad Católica de Valparaíso; Chil
Why do I like people like me?
In this paper we extend the standard model of statistical discrimination to a multidimensional framework where the accuracy of evaluators depends on how knowledgeable they are in each dimension. The model yields two main implications. First, candidates who excel in the same dimensions as the evaluator tend to be preferred. Second, if two equally productive groups of workers differ in their distribution of ability across dimensions group discrimination will arise unless (i) evaluators are well informed about the extent of these differences and (ii) evaluators can take candidates' group belonging into account in their assessmentsWe acknowledge the financial support of the Social Sciences and
Humanities Research Council of Canada and the Spanish Ministry of Science and Technology
(research grants ECO2008-06395-C05-05, ECO2008-01116 and ECO2008-03468
An Empirical Air-to-Ground Channel Model Based on Passive Measurements in LTE
In this paper, a recently conducted measurement campaign for
unmanned-aerial-vehicle (UAV) channels is introduced. The downlink signals of
an in-service long-time-evolution (LTE) network which is deployed in a suburban
scenario were acquired. Five horizontal and five vertical flight routes were
considered. The channel impulse responses (CIRs) are extracted from the
received data by exploiting the cell specific signals (CRSs). Based on the
CIRs, the parameters of multipath components (MPCs) are estimated by using a
high-resolution algorithm derived according to the space-alternating
generalized expectation-maximization (SAGE) principle. Based on the SAGE
results, channel characteristics including the path loss, shadow fading, fast
fading, delay spread and Doppler frequency spread are thoroughly investigated
for different heights and horizontal distances, which constitute a stochastic
model.Comment: 15 pages, submitted version to IEEE Transactions on Vehicular
Technology. Current status: Early acces
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