Do Salaries Improve Worker Performance?

We establish the effects of salaries on worker performance by exploiting a natural experiment in which some workers in a particular occupation (football referees) switch from short-term contracts to salaried contracts. Worker performance improves among those who move onto salaried contracts relative to those who do not. The finding is robust to the introduction of worker fixed effects indicating that it is not driven by better workers being awarded salary contracts. Nor is it sensitive to workers sorting into or out of the profession. Improved performance could arise from the additional effort workers exert due to career concerns, the higher income associated with career contracts (an efficiency wage effect) or improvements in worker quality arising from off-the-job training which accompanies the salaried contracts.

Worker Needs and Voice in the US and the UK

Workers have responded differently to declining union density in the US and UK. US workers have unfilled demand for unions whereas many UK workers free-ride at unionized workplaces. To explain this difference, we create a scalar measure of worker needs for representation and relate desire for unionism to this measure and to the choices that the US and UK labor relations systems offer workers. Our measure of needs has similar properties across countries and is the single most important determinant of worker desire for unions and collective representation. Conditional on needs, we find that in both countries workers are more favourable to unions when management is positive toward unions, but also favor them when management strongly opposes unionism, compared to management having a neutral view. Much of the difference in the response of US and UK workers to declining unionism appears to be due to the different institutional arrangements for voice that the countries offer to workers.

Employee stock purchase plans – gift or incentive? evidence from a multinational corporation

Many large listed firms offer workers the opportunity to buy shares in the firm at discounted rates through employee stock purchase plans (ESPP). The discounted rate creates a gift exchange, where the firm hopes that workers who accept the gift reciprocate with greater loyalty and effort. But ESPPs diverge from standard gift exchange or efficiency wage models. Employees have to invest some of their own money by purchasing shares at the discounted rate to accept the gift. A sizeable number choose to reject the gift. In addition, the value of the ESPP gift varies with the share price and thus with the performance of the firm and the effort of workers in total. For workers who buy subsidized shares, an ESPP sets up a group incentive pay system analogous to profit sharing, all-employee stock options, or an employment ownership scheme that makes part of workers' compensation depend on company performance

Employee perceptions of working conditions and the desire for worker representation in Britain and the US

This paper explores the link between employee perceptions of working conditions and the desire for worker representation in Britain and the US. We find that the distribution of employee perceptions of poor working conditions is similar in Britain and the US; similar factors affect the number of perceived poor working conditions; and the perception of poor working conditions is strongly associated with the desire for union representation. The nature of workplaces, as opposed to employees’ characteristics, is the predominant factor determining employee perceptions of poor working conditions

Kepler Observations of Three Pre-Launch Exoplanet Candidates: Discovery of Two Eclipsing Binaries and a New Exoplanet

Three transiting exoplanet candidate stars were discovered in a ground-based photometric survey prior to the launch of NASA's {\it Kepler} mission. {\it Kepler} observations of them were obtained during Quarter 1 of the {\it Kepler} mission. All three stars are faint by radial velocity follow-up standards, so we have examined these candidates with regard to eliminating false positives and providing high confidence exoplanet selection. We present a first attempt to exclude false positives for this set of faint stars without high resolution radial velocity analysis. This method of exoplanet confirmation will form a large part of the {\it Kepler} mission follow-up for Jupiter-sized exoplanet candidates orbiting faint stars. Using the {\it Kepler} light curves and pixel data, as well as medium resolution reconnaissance spectroscopy and speckle imaging, we find that two of our candidates are binary stars. One consists of a late-F star with an early M companion while the other is a K0 star plus a late M-dwarf/brown dwarf in a 19-day elliptical orbit. The third candidate (BOKS-1) is a $r$=15 G8V star hosting a newly discovered exoplanet with a radius of 1.12 R$_{Jupiter}$ in a 3.9 day orbit.Comment: Accepted for publication in The Astrophysical Journa

Kepler Observations of the Three Pre-Launch Exoplanet Candidates: Discover of Two Eclipsing Binaries and a New Exoplanet

Three transiting exoplanet candidate stars were discovered in a ground-based photometric survey prior to the launch of NASA's Kepler mission. Kepler observations of them were obtained during Quarter 1 of the Kepler mission. All three stars are faint by radial velocity follow-up standards, so we have examined these candidates with regard to eliminating false positives and providing high confidence exoplanet selection. We present a first attempt to exclude false positives for this set of faint stars without high-resolution radial velocity analysis. This method of exoplanet confirmation will form a large part of the Kepler mission follow-up for Jupiter-sized exoplanet candidates orbiting faint stars. Using the Kepler light curves and pixel data, as well as medium-resolution reconnaissance spectroscopy and speckle imaging, we find that two of our candidates are binary stars. One consists of a late-F star with an early M companion, while the other is a K0 star plus a late M-dwarf/brown dwarf in a 19 day elliptical orbit. The third candidate (BOKS-1) is an r = 15 G8V star hosting a newly discovered exoplanet with a radius of 1.12 R_(Jupiter) in a 3.9 day orbit

Energies of knot diagrams

We introduce and begin the study of new knot energies defined on knot diagrams. Physically, they model the internal energy of thin metallic solid tori squeezed between two parallel planes. Thus the knots considered can perform the second and third Reidemeister moves, but not the first one. The energy functionals considered are the sum of two terms, the uniformization term (which tends to make the curvature of the knot uniform) and the resistance term (which, in particular, forbids crossing changes). We define an infinite family of uniformization functionals, depending on an arbitrary smooth function $f$ and study the simplest nontrivial case $f(x)=x^2$, obtaining neat normal forms (corresponding to minima of the functional) by making use of the Gauss representation of immersed curves, of the phase space of the pendulum, and of elliptic functions