Divided by choice? Private providers, patient choice and hospital sorting in the English National Health Service

A common reform used to increase consumer choice and competition in public services has been to allow private providers to compete with public incumbents. However, there remains a concern that not all consumers are able to benefit equally from wider choice. We consider the case of publicly funded elective surgery in England, where reforms in the 2000s enabled privately owned hospitals to enter the market. We show that, post-reform, poor and ethnic minority patients were much less likely to choose private hospitals; and that dominant drivers of sorting between public and private providers are health based criteria for treatment by private providers and the geographic distribution of hospitals. Counterfactual simulations suggest differences in health explain 18% of the difference in the use of private providers between rich and poor patients, while the geographic distribution of hospitals explains 61% once other sorting mechanisms - ethnicity, patient preferences, physician referral patterns - are accounted for. Although much of the observed sorting does not appear to be the result of market frictions, limited variation in payments made to hospitals according to patient health means that sorting is estimated to cost public hospitals in excess of $426,426 ($625,000) per year

Divided by choice? Private providers, patient choice and hospital sorting in the English National Health Service

Extensions of choice over public services typically aim to generate increases in competition between providers and improvements in quality, but there remains a concern that not all types of consumer are able to engage in choice. Recent reforms to the English National Healthcare Service (NHS) extended choice, by allowing patients to receive elective hospital care at privately owned hospitals in addition to traditional NHS hospitals. This paper estimates a model of patient level hospital choice, in order to understand why some types of patients are more likely to choose a privately owned hospital. The results identify mechanisms relating to local hospital provision, heterogeneous patients' preferences and GP advice that drive diff�erential patterns of healthcare services use. And they suggest extending choice requires promotion of access to reduce inequities in health care provision

Characterization of solar cells for space applications. Volume 11: Electrical characteristics of 2 ohm-cm, 228 micron wraparound solar cells as a function of intensity, temperature, and irradiation

Parametric characterization data on Spectrolab 2 by 4 cm, 2 ohm/cm, 228 micron thick wraparound cell, a candidate for the Solar Electric Propulsion Mission, are presented. These data consist of the electrical characteristics of the solar cell under a wide range of temperature and illumination intensity combinations of the type encountered in space applications

High Proper Motion Stars in the Vicinity of Sgr A*: Evidence for a Supermassive Black Hole at the Center of Our Galaxy

Over a two year period (1995-1997), we have conducted a diffraction-limited imaging study at 2.2 microns of the inner 6"x6" of the Galaxy's central stellar cluster using the Keck 10-m telescope. The K band images obtained reveal a large population of faint stars. We use an unbiased approach for identifying and selecting stars to be included in this proper motion study, which results in a sample of 90 stars with brightness ranging from K=9-17 and velocities as large as 1,400+-100 km/sec. Compared to earlier work (Eckart et al. 1997; Genzel et al. 1997), the source confusion is reduced by a factor of 9, the number of stars with proper motion measurement in the central 25 arcsec^2 of our galaxy is doubled, and the accuracy of the velocity measurements in the central 1 arcsec^2 is improved by a factor of 4. The peaks of both the stellar surface density and the velocity dispersion are consistent with the position of the unusual radio source and blackhole candidate, Sgr A*, suggesting that Sgr A* is coincident (+-0."1) with the dynamical center of the Galaxy. As a function of distance from Sgr A*, the velocity dispersion displays a falloff well fit by Keplerian motion about a central dark mass of 2.6(+-0.2)x10^6 Mo confined to a volume of at most 10^-6 pc^3, consistent with earlier results. Although uncertainties in the measurements mathematically allow for the matter to be distributed over this volume as a cluster, no realistic cluster is physically tenable. Thus, independent of the presence of Sgr A*, the large inferred central density of at least 10^12 Mo/pc^3, which exceeds the volume-averaged mass densities found at the center of any other galaxy, leads us to the conclusion that our Galaxy harbors a massive central black hole.Comment: 19 pages, 8 figures, accepted for publications in the Astrophysical Journa

Characterization of solar cells for space applications. Volume 12: Electrical characteristics of Solarex BSF, 2-ohm-cm, 50-micron solar cells (1978 pilot line) as a function of intensity, temperature, and irradiation

Electrical characteristics of Solarex back-surface-field, 2-ohm-cm, 50-micron N/P silicon solar cells are presented in graphical and tabular format as a function of solar illumination intensity, temperature, and irradiation

Characterization of solar cells for space applications. Volume 8: Electrical characteristics of Spectrolab BSF, BSR, textured 290-micron solar cells (K7) as a function of intensity, temperature and irradiation

A set of parametric data is presented on the Spectrolab textured, back-surface-field, back-surface-reflector solar cell which is a commercially available product

Sgr A* Polarization: No ADAF, Low Accretion Rate, and Non-Thermal Synchrotron Emission

The recent detection of polarized radiation from Sgr A* requires a non-thermal electron distribution for the emitting plasma. The Faraday rotation measure must be small, placing strong limits on the density and magnetic field strength. We show that these constraints rule out advection-dominated accretion flow models. We construct a simple two-component model which can reproduce both the radio to mm spectrum and the polarization. This model predicts that the polarization should rise to nearly 100% at shorter wavelengths. The first component, possibly a black-hole powered jet, is compact, low density, and self-absorbed near 1 mm with ordered magnetic field, relativistic Alfven speed, and a non-thermal electron distribution. The second component is poorly constrained, but may be a convection-dominated accretion flow with dM/dt~10^-9 M_Sun/yr, in which feedback from accretion onto the black hole suppresses the accretion rate at large radii. The black hole shadow should be detectable with sub-mm VLBI.Comment: 4 pages, 1 figure, accepted by ApJL, several changes from submitted versio

Characterization of solar cells for space applications. Volume 13: Electrical characteristics of Hughes LPE gallium arsenide solar cells as a function of intensity and temperature

Electrical characteristics of Hughes Liquid phase epitaxy, P/N gallium aluminum arsenide solar cells are presented in graphical and tabular format as a function of solar illumination intensity and temperature