John E. Everett

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Several methods, mostly based on a consideration of the eigenvalues, have been previously used to determine the number of factors to retain in a factor analysis. This paper shows how split-half factor comparabilities, based on factor scores, can provide a direct and unambiguous method of determining the number of reliable factors that should be retained,(More)
We apply a wind model, driven by combined cosmic-ray and thermal-gas pressure, to the Milky Way, and show that the observed Galactic diffuse soft X-ray emission can be better explained by a wind than by previous static gas models. We find that cosmic-ray pressure is essential to driving the observed wind. Having thus defined a “best-fit” model for a(More)
We present observations of probable line-of-sight acceleration of a broad absorption trough of C IV in the quasar SDSS J024221.87+004912.6. We also discuss how the velocity overlap of two other outflowing systems in the same object constrains the properties of the outflows. The Si IV doublet in each system has one unblended transition and one transition(More)
We present low-resolution ultraviolet spectra of 14 low-redshift (zem P 0:8) quasars observed with the Hubble Space Telescope STIS as part of a Snapshot project to understand the relationship between quasar outflows and luminosity. By design, all observations cover the C iv emission line. Ten of the quasars are from the Hamburg-ESO catalog, three are from(More)
As a result of deep hard X-ray observations by Chandra and XMM-Newton a significant fraction of the cosmic X-ray background (CXRB) has been resolved into individual sources. These objects are almost all active galactic nuclei (AGN) and optical followup observations find that they are mostly obscured Type 2 AGN, have Seyfert-like X-ray luminosities (i.e., L(More)
By fitting the classical Rotating Vector Model (RVM) to high quality polarization data for selected radio pulsars, we find the inclination of the magnetic axis to the spin axis, α, as well as the minimum angle between the line of sight and the magnetic axis, β, for ten objects. We give a full treatment of statistical errors in the fitting process. We also(More)
Discrimination in organizations based on race or sex is a contentious issue. Sensible discussion of the issue will be enhanced by the availability of measures of discrimination enabling comparisons to be made between organizations and across time. Linear models are of limited validity. A contingency table approach is suggested. Given an observed(More)
We present a self-consistent, semi-analytical dynamical model of disk driven outflows in AGNs that are accelerated by a combination of magnetic stresses and radiation pressure. This model will make it possible to examine scenarios in which the wind is homogeneous as well as cases where it consists of dense clouds embedded in a more tenuous, magnetized(More)
Bauxite is mined and transported by conveyor to a processing plant, screened and washed, then placed into blended stockpiles to feed the alumina refinery. While being stacked to the stockpile, the ore is sampled. Completed stockpiles must be acceptably close to target grade (composition), not only in alumina, but also in residual silica, carbon and sodium(More)