The Effects Of Scoring Technique On Situational Judgment Test Validity

Situational Judgment Tests (SJTs) are frequently used by organizations as a face-valid selection measure with low adverse impact and a relatively strong relationship with relevant criteria. Despite their common use, there remain several research questions regarding the theoretical foundations and characteristics of SJTs. Additionally, developments in SJT scoring provide fertile ground for research to validate new scoring techniques to better predict criteria of interest. Motowidlo and his colleagues (2006) recently developed a scoring technique for SJTs based on the principle of Implicit Trait Policies (ITPs) which are implicit beliefs concerning the effectiveness of different behavioral choices that demonstrate varying levels of targeted traits. Individuals high in these targeted traits will rate item responses that demonstrate high levels of that particular trait as more effective. Taking into consideration this new method, and also considering the multitude of scoring methods already available to test developers, it logically follows that these different scoring methods will have different correlations with constructs of interest, and that by using this new method it may be possible to achieve a much higher correlation with personality. The effects of scoring technique on relationships between SJT scores and constructs of interest such as personality will in turn have effects on the criterion validity of the SJT. This research explored how scoring methods affected the relationship SJT scores have with general mental ability, personality traits, typical performance, and maximum performance. Results indicated significant differential validity as a function of the respondents‟ race. For minority participants, SJT scores predicted maximum performance ratings in a simulation exercise but not typical performance ratings provided by familiar peers. However, the reverse was true for Caucasian participants. The two scoring methods demonstrated differential validity. However, the nature of these differences varied as a function of the iv performance dimension in question (i.e., agreeableness, extraversion). Implications for future research will be discussed as well as the practical implications of these findings

Modeling the Behavior of the Surface to Liquid Interfaces in an Electrolytic Liquid

Understanding the mechanism for charge transfer between electrodes within an electrolyte dissolved in water is vital to better understanding the sources of electrical noise in the system. This research compares the electrical properties of liquid top gated graphene devices with the properties of two metal probes to model the system. By measuring the impedance of these systems at different frequencies, it is possible to develop a model of their electrical properties and to consider techniques to improve signal to noise at graphene interfaces

The Role of Projection in the Control of Bird Flocks

Swarming is a conspicuous behavioural trait observed in bird flocks, fish shoals, insect swarms and mammal herds. It is thought to improve collective awareness and offer protection from predators. Many current models involve the hypothesis that information coordinating motion is exchanged between neighbors. We argue that such local interactions alone are insufficient to explain the organization of large flocks of birds and that the mechanism for the exchange of long-ranged information necessary to control their density remains unknown. We show that large flocks self-organize to the maximum density at which a typical individual is still just able to see out of the flock in many directions. Such flocks are marginally opaque - an external observer can also just still see a substantial fraction of sky through the flock. Although seemingly intuitive we show that this need not be the case; flocks could easily be highly diffuse or entirely opaque. The emergence of marginal opacity strongly constrains how individuals interact with each other within large swarms. It also provides a mechanism for global interactions: An individual can respond to the projection of the flock that it sees. This provides for faster information transfer and hence rapid flock dynamics, another advantage over local models. From a behavioural perspective it optimizes the information available to each bird while maintaining the protection of a dense, coherent flock.Comment: PNAS early edition published online at http://www.pnas.org/cgi/doi/10.1073/pnas.140220211

Synchronization of dynamical hypernetworks: dimensionality reduction through simultaneous block-diagonalization of matrices

We present a general framework to study stability of the synchronous solution for a hypernetwork of coupled dynamical systems. We are able to reduce the dimensionality of the problem by using simultaneous block-diagonalization of matrices. We obtain necessary and sufficient conditions for stability of the synchronous solution in terms of a set of lower-dimensional problems and test the predictions of our low-dimensional analysis through numerical simulations. Under certain conditions, this technique may yield a substantial reduction of the dimensionality of the problem. For example, for a class of dynamical hypernetworks analyzed in the paper, we discover that arbitrarily large networks can be reduced to a collection of subsystems of dimensionality no more than 2. We apply our reduction techique to a number of different examples, including a class of undirected unweighted hypermotifs of three nodes.Comment: 9 pages, 6 figures, accepted for publication in Phys. Rev.

Genome Assembly Improvement and Mapping Convergently Evolved Skeletal Traits in Sticklebacks with Genotyping-by-Sequencing.

Marine populations of the threespine stickleback (Gasterosteus aculeatus) have repeatedly colonized and rapidly adapted to freshwater habitats, providing a powerful system to map the genetic architecture of evolved traits. Here, we developed and applied a binned genotyping-by-sequencing (GBS) method to build dense genome-wide linkage maps of sticklebacks using two large marine by freshwater F2 crosses of more than 350 fish each. The resulting linkage maps significantly improve the genome assembly by anchoring 78 new scaffolds to chromosomes, reorienting 40 scaffolds, and rearranging scaffolds in 4 locations. In the revised genome assembly, 94.6% of the assembly was anchored to a chromosome. To assess linkage map quality, we mapped quantitative trait loci (QTL) controlling lateral plate number, which mapped as expected to a 200-kb genomic region containing Ectodysplasin, as well as a chromosome 7 QTL overlapping a previously identified modifier QTL. Finally, we mapped eight QTL controlling convergently evolved reductions in gill raker length in the two crosses, which revealed that this classic adaptive trait has a surprisingly modular and nonparallel genetic basis

Monitoring multicomponent transport using in-situ FTIR spectroscopy

The permeation of aqueous solutes through membranes is of critical importance in many applications, including fuel cells and solar-driven electrochemical cells. In these devices, the undesirable crossover of small organics through a membrane separating halves of the electrochemical cell reduces device efficiency. The techniques traditionally used to measure organic permeation through a membrane, such as gas chromatography, typically require aliquot sampling and are limited by the chromatograph’s capability to resolve analytes and water. In-situ FTIR spectroscopy, is capable of quantitative measurement of organic permeation through membranes in a simple diffusion cell without aliquot sampling. Furthermore, in-situ FTIR is capable of the simultaneous measurement of multicomponent permeation, provided that each analyte has a distinct IR signature. Within the context of devices for solar fuel production, membranes are desired that facilitate the ion transport necessary to feed the electrochemical reactions while meeting various additional selectivity and permeability demands. For example, in an artificial photosynthesis device, water is oxidized to O2 and CO2 is reduced to a liquid transportation fuel, such as methanol or ethanol. However, the catalysts responsible for CO2 reduction are non-specific, producing a library of small molecule products. Here, we demonstrate the use of in-situ FTIR spectroscopy to quantitatively determine the concentration of single and multicomponent mixtures of various CO2 reduction products including methanol, formate and acetate. We then apply this methodology to the in-situ monitoring of the permeation of single and multicomponent mixtures across commercially available membranes, such as Nafion 117 and Selemion AMV, using a diffusion cell. Membrane permeabilities are extracted from time-resolved half-cell concentration data using fee volume models. Membrane permeabilities and selectivities calculated from the single component permeation experiments are compared to those calculated for solutes in multicomponent permeation experiments. In some instances, the membrane permeability to an organic solute changes substantially, sometimes by orders of magnitude, when co-solutes are present. These results and their implications will be discussed in the context of next-generation energy devices. Please click Additional Files below to see the full abstract

Grist: Grid-based Data Mining for Astronomy

The Grist project is developing a grid-technology based system as a research environment for astronomy with massive and complex datasets. This knowledge extraction system will consist of a library of distributed grid services controlled by a work ow system, compliant with standards emerging from the grid computing, web services, and virtual observatory communities. This new technology is being used to find high redshift quasars, study peculiar variable objects, search for transients in real time, and fit SDSS QSO spectra to measure black hole masses. Grist services are also a component of the "hyperatlas" project to serve high-resolution multi-wavelength imagery over the Internet. In support of these science and outreach objectives, the Grist framework will provide the enabling fabric to tie together distributed grid services in the areas of data access, federation, mining, subsetting, source extraction, image mosaicking, statistics, and visualization

ECONOMIC IMPACT EVALUATION OF GLOBAL MARKETING SUPPORT SERVICES - AN EXPORTS ASSISTANCE PROGRAM ON THE ECONOMY OF ARKANSAS

This study determines the impact of Global Marketing Support Services (GMSS) - an exports assistance program in assisting 13 small and medium sized businesses to export. The total impact of exports (direct, indirect and induced effects) on added value, employment, labor income and tax impacts in Arkansas are estimated using Impact Analysis for Planning (IMPLAN).International Relations/Trade,

Tuning Curves, Neuronal Variability, and Sensory Coding

Tuning curves are widely used to characterize the responses of sensory neurons to external stimuli, but there is an ongoing debate as to their role in sensory processing. Commonly, it is assumed that a neuron's role is to encode the stimulus at the tuning curve peak, because high firing rates are the neuron's most distinct responses. In contrast, many theoretical and empirical studies have noted that nearby stimuli are most easily discriminated in high-slope regions of the tuning curve. Here, we demonstrate that both intuitions are correct, but that their relative importance depends on the experimental context and the level of variability in the neuronal response. Using three different information-based measures of encoding applied to experimentally measured sensory neurons, we show how the best-encoded stimulus can transition from high-slope to high-firing-rate regions of the tuning curve with increasing noise level. We further show that our results are consistent with recent experimental findings that correlate neuronal sensitivities with perception and behavior. This study illustrates the importance of the noise level in determining the encoding properties of sensory neurons and provides a unified framework for interpreting how the tuning curve and neuronal variability relate to the overall role of the neuron in sensory encoding