Environmental Decision Making and Risk Management for Groundwater Systems

With an eye to a specific application in New Zealand, Ms. Gough explores the use of risk management approaches for environmental decision making at strategic, policy, management and operational levels

Vainu Bappu Memorial Lecture: What is a sunspot?

Sunspots have been known in the West since Galileo Galilei and Thomas Harriot first used telescopes to observe the Sun nearly four centuries ago; they have been known to the Chinese for more than two thousand years. They appear as relatively dark patches on the surface of the Sun, and are caused by concentrations of magnetism which impede the flow of heat from deep inside the Sun up to its othewise brilliant surface. The spots are not permanent: the total number of spots on the Sun varies cyclically in time, with a period of about eleven years, associated with which there appear to be variations in our climate. When there are many spots, it is more dangerous for spacecraft to operate. The cause of the spots is not well understood; nor is it known for sure how they die. Their structure beneath the surface of the Sun is in some dispute, although much is known about their properties at the surface, including an outward material flow which was discovered by John Evershed observing the Sun from Kodaikanal a hundred years ago. I shall give you a glimpse of how we are striving to deepen our understanding of these fascinating features, and of some of the phenomena that appear to be associated with them.Comment: Lecture delivered at the Indian Institute of Astrophysics, December 2008 Typing errors corrected To appear in Magnetic Coupling between the Interior and the Atmosphere of the Sun, ed. S.S. Hasan & R.J. Rutten, Astr. Sp. Sci. Pro

Progress report on solar age calibration

We report on an ongoing investigation into a seismic calibration of solar models designed for estimating the main-sequence age and a measure of the chemical abundances of the Sun. Only modes of low degree are employed, so that with appropriate modification the procedure could be applied to other stars. We have found that, as has been anticipated, a separation of the contributions to the seismic frequencies arising from the relatively smooth, glitch-free, background structure of the star and from glitches produced by helium ionization and the abrupt gradient change at the base of the convection zone renders the procedure more robust than earlier calibrations that fitted only raw frequencies to glitch-free asymptotics. As in the past, we use asymptotic analysis to design seismic signatures that are, to the best of our ability, contaminated as little as possible by those uncertain properties of the star that are not directly associated with age and chemical composition. The calibration itself, however, employs only numerically computed eigenfrequencies. It is based on a linear perturbation from a reference model. Two reference models have been used, one somewhat younger, the other somewhat older than the Sun. The two calibrations, which use BiSON data, are more-or-less consistent, and yield a main-sequence age $t_\odot=4.68\pm0.02$Gy, coupled with a formal initial heavy-element abundance $Z=0.0169\pm0.0005$. The error analysis has not yet been completed, so the estimated precision must be taken with a pinch of salt.Comment: 8 pages, 3 figures, in L. Deng, K.L. Chan, C. Chiosi, eds, The Art of Modelling Stars in the 21st Century, Proc. IAU Symp. No. 252, invited contributed pape

Comparing Mandatory Arbitration and Litigation: Access, Process, and Outcomes

[Excerpt] What do we know about mandatory arbitration and its impact? Some existing studies have examined samples of employment arbitration cases, usually obtained from the American Arbitration Association (AAA), which is currently the largest arbitration service provider in the employment area. Although some early studies found relatively high employee win rates and damage awards in arbitration, comparable to those in litigation, these results were mainly based on arbitration under individually negotiated agreements or in the securities industry and involved relatively highly paid individuals. More recent studies using larger samples of cases based on mandatory arbitration agreements find much lower employee win rates and smaller damage amounts than typical in litigation. Existing studies, however, have not been able to account for differences in the types of cases that are heard in arbitration. In particular, previous work has not been able to systematically compare outcomes in arbitration and litigation in the same study. In this study, we take a new approach to investigating mandatory arbitration that allows us to do a systematic comparison of arbitration and litigation, accounting for key factors that differentiate between the types of cases brought in these forums. We do this by collecting survey data on a comparable sample of arbitration and litigation cases from attorneys involved in those cases. We also investigate the overall experiences of the attorneys in representing plaintiff employees in mandatory arbitration and litigation. The ability to obtain and finance legal representation is a crucial, yet understudied aspect of the system of enforcement of employment rights. Absent the ability to obtain effective representation, employees may be unable to pursue and win cases even where their statutory rights have been violated. One of the potential benefits held out for arbitration compared to litigation is that it could provide a cheaper, more accessible forum to allow employee claims to be heard and adjudicated. It is certainly the case that existing research indicates many limitations of the litigation system, particularly the relatively poor outcomes obtained by plaintiff employees compared to other litigants. What we are able to investigate empirically in this study is whether mandatory arbitration ameliorates some of the limitations of the litigation system or whether it is equally or even more limited in its accessibility

Individual Employment Rights Arbitration in the United States: Actors and Outcomes

The authors examine disposition statistics from employment arbitration cases administered over an 11-year period by the American Arbitration Association (AAA) to investigate the process of dispute resolution in this new institution of employment relations. They investigate the predictors of settlement before the arbitration hearing and then estimate models for the likelihood of employee wins and damage amounts for the 2,802 cases that resulted in an award. Their findings show that larger-scale employers who are involved in more arbitration cases tend to have higher win rates and have lower damage awards made against them. This study also provides evidence of a significant repeat employer-arbitrator pair effect; employers that use the same arbitrator on multiple occasions win more often and have lower damages awarded against them than do employers appearing before an arbitrator for the first time. The authors find that self-represented employees tend to settle cases less often, win cases that proceed to a hearing less often, and receive lower damage awards. Female arbitrators and experienced professional labor arbitrators render awards in favor of employees less often than do male arbitrators and other arbitrators

On the identification of normal modes of oscillation from observations of the solar periphery

The decomposition of solar oscillations into their constituent normal modes requires a knowledge of both the spatial and temporal variation of the perturbation to the Sun's surface. The task is especially difficult when only limited spatial information is available. Observations of the limb darkening function, for example, are probably sensitive to too large a number of modes to permit most of the modes to be identified in a power spectrum of measurements at only a few points on the limb, unless the results are combined with other data. A procedure was considered by which the contributions from quite small groups of modes to spatially well resolved data obtained at any instant can be extracted from the remaining modes. Combining these results with frequency information then permits the modes to be identified, at least if their frequencies are low enough to ensure that modes of high degree do not contribute substantially to the signal