13,957 research outputs found
The influence of early efficacy beliefs on teams' reactions to failing to reach performance goals
Cataloged from PDF version of article.Although a considerable amount of theoretical and empirical attention has been devoted to understanding individuals' responses to goal–performance discrepancies (GPDs), little attention has been devoted to examining how teams respond to GPDs. The present research sought to examine how teams responded to negative GPDs. We predicted that failing to reach higher goals would be perceived as less negative than failing to reach lower goals, and we examined the moderating influence of setting higher versus lower goals on how teams responded to performance that fell short of those goals. We also examined the role that efficacy beliefs that were formed early in those teams played in further explaining these effects. Results from 94 teams who all failed to reach self-set goals revealed that teams that failed to reach higher goals downwardly revised their goals less than teams that failed to reach lower goals. Early efficacy beliefs further explained these effects. High efficacy beliefs lessened the negative effects of failing to reach lower goals on subsequent goals. High efficacy beliefs also lessened the negative effects of failing to reach higher goals while low efficacy beliefs strengthened the negative effects of failing to reach higher goals. The implications of these findings for theory, research, and practice are discussed
Peculiarities in the Spectrum of the Adjoint Scalar Kinetic Operator in Yang-Mills Theory
We study the spectrum of low-lying eigenmodes of the kinetic operator for
scalar particles, in the color adjoint representation of Yang-Mills theory. The
kinetic operator is the covariant Laplacian, plus a constant which serves to
renormalize mass. In the pure gauge theory, our data indicates that the
interval between the lowest eigenvalue and the mobility edge tends to infinity
in the continuum limit. On these grounds, it is suggested that the perturbative
expression for the scalar propagator may be misleading even at distance scales
that are small compared to the confinement scale. We also measure the density
of low-lying eigenmodes, and find a possible connection to multi-critical
matrix models of order m=1.Comment: 9 pages, 14 figure
Spectral analysis of deformed random networks
We study spectral behavior of sparsely connected random networks under the
random matrix framework. Sub-networks without any connection among them form a
network having perfect community structure. As connections among the
sub-networks are introduced, the spacing distribution shows a transition from
the Poisson statistics to the Gaussian orthogonal ensemble statistics of random
matrix theory. The eigenvalue density distribution shows a transition to the
Wigner's semicircular behavior for a completely deformed network. The range for
which spectral rigidity, measured by the Dyson-Mehta statistics,
follows the Gaussian orthogonal ensemble statistics depends upon the
deformation of the network from the perfect community structure. The spacing
distribution is particularly useful to track very slight deformations of the
network from a perfect community structure, whereas the density distribution
and the statistics remain identical to the undeformed network. On
the other hand the statistics is useful for the larger deformation
strengths. Finally, we analyze the spectrum of a protein-protein interaction
network for Helicobacter, and compare the spectral behavior with those of the
model networks.Comment: accepted for publication in Phys. Rev. E (replaced with the final
version
Level density for deformations of the Gaussian orthogonal ensemble
Formulas are derived for the average level density of deformed, or
transition, Gaussian orthogonal random matrix ensembles. After some general
considerations about Gaussian ensembles we derive formulas for the average
level density for (i) the transition from the Gaussian orthogonal ensemble
(GOE) to the Poisson ensemble and (ii) the transition from the GOE to GOEs.Comment: 7 pages revtex4, 5 eps figures, submitted to Phys. Rev.
Transport behaviour of a Bose Einstein condensate in a bichromatic optical lattice
The Bloch and dipole oscillations of a Bose Einstein condensate (BEC) in an
optical superlattice is investigated. We show that the effective mass increases
in an optical superlattice, which leads to localization of the BEC, in
accordance with recent experimental observations [16]. In addition, we find
that the secondary optical lattice is a useful additional tool to manipulate
the dynamics of the atoms.Comment: Modified manuscrip
Fermi Edge Singularities in the Mesoscopic Regime: II. Photo-absorption Spectra
We study Fermi edge singularities in photo-absorption spectra of generic
mesoscopic systems such as quantum dots or nanoparticles. We predict deviations
from macroscopic-metallic behavior and propose experimental setups for the
observation of these effects. The theory is based on the model of a localized,
or rank one, perturbation caused by the (core) hole left behind after the
photo-excitation of an electron into the conduction band. The photo-absorption
spectra result from the competition between two many-body responses, Anderson's
orthogonality catastrophe and the Mahan-Nozieres-DeDominicis contribution. Both
mechanisms depend on the system size through the number of particles and, more
importantly, fluctuations produced by the coherence characteristic of
mesoscopic samples. The latter lead to a modification of the dipole matrix
element and trigger one of our key results: a rounded K-edge typically found in
metals will turn into a (slightly) peaked edge on average in the mesoscopic
regime. We consider in detail the effect of the "bound state" produced by the
core hole.Comment: 16 page
Physical Conditions in Barnard\u27s Loop, Components of the Orion-Eridanus Bubble, and Implications for the Warm Ionized Medium Component of the Interstellar Medium
We have supplemented existing spectra of Barnard\u27s Loop with high accuracy spectrophotometry of one new position. Cloudy photoionization models were calculated for a variety of ionization parameters and stellar temperatures and compared with the observations. After testing the procedure with recent observations of M43, we establish that Barnard\u27s Loop is photoionized by four candidate ionizing stars, but agreement between the models and observations is only possible if Barnard\u27s Loop is enhanced in heavy elements by about a factor of 1.4. Barnard\u27s Loop is very similar in properties to the brightest components of the Orion-Eridanus Bubble and the warm ionized medium (WIM). We are able to establish models that bound the range populated in low-ionization color-color diagrams (I([S II])/I(Hα) versus I([N II])/I(Hα)) using only a limited range of ionization parameters and stellar temperatures. Previously established variations in the relative abundance of heavy elements render uncertain the most common method of determining electron temperatures for components of the Orion-Eridanus Bubble and the WIM based only on the I([N II])/I(Hα) ratio, although we confirm that the lowest surface brightness components of the WIM are on average of higher electron temperature. The electron temperatures for a few high surface brightness WIM components determined by direct methods are comparable to those of classical bright H II regions. In contrast, the low surface brightness H II regions studied by the Wisconsin Hα Mapper are of lower temperatures than the classical bright H II regions
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