1,009 research outputs found
Recommended from our members
Rounding in Angoff Ratings
One common modification to the Angoff standard-setting method is to have panelists round their ratings to the nearest 0.05 or 0.10 instead of 0.01. Several reasons have been offered as to why it may make sense to have panelists round their ratings to the nearest 0.05 or 0.10. In this article, we examine one reason that has been suggested, which is that even if panelists are given the opportunity to provide ratings to the nearest 0.01 they often round their ratings to the nearest 0.05 or 0.10 anyway. Using data from four standard settings, we show that in many cases ratings ended in a 0 or 5 when panelists were given the option of using a scale from 0 to 100 in one-point increments and that only about 9% of all ratings ended in a digit other than a 0 or 5. We also examined the impact of different rounding rules and we found that results were quite similar when using different rounding rules. Additional analyses showed the common phenomenon of panelists giving too high of ratings for hard items and too low of ratings for easy items in comparison to conditional p-values. It is suggested that rounding ratings to the nearest 0.05 or 0.10 represent reasonable alternatives to rounding ratings to the nearest 0.01. Accessed 1,050 times on https://pareonline.net from May 02, 2018 to December 31, 2019. For downloads from January 1, 2020 forward, please click on the PlumX Metrics link to the right
Information Integration And Performance: A Field Study And Structural Equations Analysis
The deployment of information systems technology (IST) is often justified on the presumption that improved information delivery and content will positively impact individual performance and, consequently, organizational performance. The integration of information systems undertaken by many organizations as an IST deployment tactic is based on such a presumption. This presumed relationship has not been empirically established nor has it been the subject of significant theoretical development. This investigation sought to address these deficiencies.;To provide a theoretical basis for the research, a model of information integration was constructed. This model is conceptually grounded in the work on critical success factors (CSFs). For each CSF, an information integration component is posited to exist. User information satisfaction (UIS) measures were used to operationalize constructs for information integration. Positive relationships between these constructs and performance constructs were hypothesized. Hypothesis testing and validity assessment were done by treating the model as a latent variable path model and employing Wold\u27s method of Partial Least Squares for analysis.;The study examined information use by individuals whose performance was closely tied to organizational performance. The organization was a major Canadian insurance company and the individuals were the firm\u27s sales representatives. Following identification of CSFs by an executive panel, interviews were held with 102 sales representatives. These interviews involved scale completion to capture manifestations of information integration and to validate CSFs. Measures of individual performance were obtained from archival data
Galaxy UV-luminosity function and reionization constraints on axion dark matter
If the dark matter (DM) were composed of axions, then structure formation in
the Universe would be suppressed below the axion Jeans scale. Using an analytic
model for the halo mass function of a mixed DM model with axions and cold dark
matter, combined with the abundance-matching technique, we construct the
UV-luminosity function. Axions suppress high- galaxy formation and the
UV-luminosity function is truncated at a faintest limiting magnitude. From the
UV-luminosity function, we predict the reionization history of the universe and
find that axion DM causes reionization to occur at lower redshift. We search
for evidence of axions using the Hubble Ultra Deep Field UV-luminosity function
in the redshift range -, and the optical depth to reionization,
, as measured from cosmic microwave background polarization. All probes
we consider consistently exclude from
contributing more than half of the DM, with our strongest constraint ruling
this model out at more than significance. In conservative models of
reionization a dominant component of DM with is in
tension with the measured value of , putting pressure on an
axion solution to the cusp-core problem. Tension is reduced to for
the axion contributing only half of the DM. A future measurement of the
UV-luminosity function in the range - by JWST would provide further
evidence for or against . Probing still higher masses
of will be possible using future measurements of the
kinetic Sunyaev-Zel'dovich effect by Advanced ACTPol to constrain the time and
duration of reionization.Comment: 17 pages, 8 figures, 2 tables. v2: Minor Changes. References added.
Published in MNRA
Interactions of keV sterile neutrinos with matter
A sterile neutrino with mass of several keV is a well-motivated dark-matter
candidate, and it can also explain the observed velocities of pulsars via
anisotropic emission of sterile neutrinos from a cooling neutron star. We
discuss the interactions of such relic particles with matter and comment on the
prospects of future direct detection experiments. A relic sterile neutrino can
interact, via sterile-active mixing, with matter fermions by means of
electroweak currents, with the final state containing a relativistic active
neutrino. The recoil momentum impacted onto a matter fermion is determined by
the sterile neutrino mass and is enough to ionize atoms and flip the spins of
nuclei. While this suggests a possibility of direct experimental detection, we
calculate the rates and show that building a realistic detector of the required
size would be a daunting challenge.Comment: 5 pages, 1 figur
Recommended from our members
A Comparison of Subject Matter Experts’ Perceptions and Job Analysis Surveys
Two common approaches for performing job analysis in credentialing programs are committee-based methods, which rely solely on subject matter experts’ judgments, and task inventory surveys. This study evaluates how well subject matter experts’ perceptions coincide with task inventory survey results for three credentialing programs. Results suggest that subject matter expert ratings differ in systematic ways from task inventory survey results and that task lists generated based solely on subject matter experts’ intuitions generally lead to narrower task lists. Results also indicated that there can be key differences for procedures and non-procedures, with subject matter experts’ judgments often tending to exhibit lower agreement levels with task inventory survey results for procedures than for non-procedures. We recommend that organizations performing job analyses think very carefully before relying solely on subject matter experts’ judgments as their primary method of job analysis. Accessed 1,252 times on https://pareonline.net from September 06, 2018 to December 31, 2019. For downloads from January 1, 2020 forward, please click on the PlumX Metrics link to the right
Light Scattering In The Isotropic Phase of Highly Chiral Liquid Crystals
Light-scattering measurements using circularly polarized light in a backscattering geometry are employed to measure the amplitude of fluctuations in two of the five structural modes present in the isotropic phase of chiral liquid crystals. From these measurements, the second-order transition temperatures for all five modes are then calculated. In order to investigate the effect of chirality on the fluctuations, the experiments are performed in various mixtures of the chiral liquid crystal 4’’-(2-methylbutylphenyl)-4’-(2-methylbutyl)-4-biphenylcarboxylate (CE2) and the nonchiral liquid crystal 4-n-pentylbenzenethio-4’-n-heptyloxybenzoate(7¯S5). The results show that fluctuations in the five modes are independent in low-chirality mixtures, and, as predicted by theory, the second-order transition temperatures grow farther apart as the chirality increases. In highly chiral mixtures, fluctuations in the mode with the highest second-order transition temperature deviate from the normal temperature dependence, resulting in a lower second-order transition temperature for this mode. The probable explanation for this is that fluctuations in the structural modes are coupled in high-chirality systems, but at present no theoretical calculations exist
- …