Tournaments with price-setting agents

,Tournaments

Tournaments with prize-setting agents

In many tournaments it is the contestants themselves who determine reward allocation. Labor-union members bargain over wage distribution, and many firms allow self-managed teams to freely determine internal resource allocation, incentive structure, and division of labour. We analyze, and test experimentally, a rank-order tournament where heterogenous agents determine the spread between winner prize and looser prize. We investigate the relationship between prize spread, uncertainty (i.e. noise between e¤ort and performance), heterogeneity and effort. The paper challenges well-known results from tournament theory. We find that a large prize spread is associated with low degree of uncertainty and high degree of heterogeneity, and that heterogeneity triggers effort. By and large, our real-effort experiment supports the theoretical predictions.Rank-order tournament; prize spread; ability-difference

Risk-taking on Behalf of Others

We present an experimental study on how people take risk on behalf of others. We use three different elicitation methods, and study how each subject makes decisions both on behalf of own money and on behalf of another individual’s money. We find a weak tendency of lower risk-taking with others’ money compared to own money. However, subjects believe that other participants take more risk with other people’s money than with their own. At the same time, subjects on average think that others are more risk averse than themselves. The data also reveals that subjects are quite inconsistent when making risk decisions on behalf of others, indicating random behavior. A large majority of subjects alternates between taking more risk, less risk or the same amount of risk with other people’s money compared to own money

Fair advice

Millions of investors place their trust in financial advisors who may have incentives to give them bad advice. This may indicate that advisors behave more fairly than economic theory predicts. In this paper, we present results from a large-scale experiment studying advice-giving under conflicting interests. We use a binary dictator game as a baseline and transform it into a situation where the dictator gives advice that may or may not be followed. Our results show that people are averse to giving bad advice. When subjects are given the role of advisor, they behave less selfishly, even when the economic incentives and considerations remain the same as in the baseline dictator game.publishedVersio

Evidence for Particle Acceleration to the Knee of the Cosmic Ray Spectrum in Tycho’s Supernova Remnant

Supernova remnants (SNRs) have long been assumed to be the source of cosmic rays (CRs) up to the knee of the CR spectrum at 10^15 eV, accelerating particles to relativistic energies in their blast waves by the process of diffusive shock acceleration (DSA). Since cosmic ray nuclei do not radiate efficiently, their presence must be inferred indirectly. Previous theoretical calculations and X-ray observations show that CR acceleration modifies significantly the structure of the SNR and greatly amplifies the interstellar magnetic field. We present new, deep X-ray observations of the remnant of Tycho\u27s supernova (SN 1572, henceforth Tycho), which reveal a previously unknown, strikingly ordered pattern of non-thermal high-emissivity stripes in the projected interior of the remnant, with spacing that corresponds to the gyroradii of 10^14 - 10^15 eV} protons. Spectroscopy of the stripes shows the plasma to be highly turbulent on the (smaller) scale of the Larmor radii of TeV energy electrons. Models of the shock amplification of magnetic fields produce structure on the scale of the gyroradius of the highest energy CRs present, but they do not predict the highly-ordered pattern we observe. We interpret the stripes as evidence for acceleration of particles to near the knee of the CR spectrum in regions of enhanced magnetic turbulence, while the observed highly ordered pattern of these features provides a new challenge to models of DSA

Tilbaketrukne elever og sosial samhandling : en kvalitativ studie om hvordan lærere, helsesøster og psykisk helserådgiver i ungdomsskolen tilpasser for tilbaketrukne elever for økt deltakelse i sosial samhandling

Masteroppgave i tilpasset opplæring - Nord universitet, 201

The Flux Auto- and Cross-Correlation of the Lyman-alpha Forest. II. Modelling Anisotropies with Cosmological Hydrodynamic Simulations

The isotropy of the Lyman-alpha forest in real-space uniquely provides a measurement of cosmic geometry at z > 2. The angular diameter distance for which the correlation function along the line of sight and in the transverse direction agree corresponds to the correct cosmological model. However, the Lyman-alpha forest is observed in redshift-space where distortions due to Hubble expansion, bulk flows, and thermal broadening introduce anisotropy. Similarly, a spectrograph's line spread function affects the autocorrelation and cross-correlation differently. In this the second paper of a series on using the Lyman-alpha forest observed in pairs of QSOs for a new application of the Alcock-Paczynski (AP) test, these anisotropies and related sources of potential systematic error are investigated with cosmological hydrodynamic simulations. Three prescriptions for galactic outflow were compared and found to have only a marginal effect on the Lyman-alpha flux correlation (which changed by at most 7% with use of the currently favored variable-momentum wind model vs. no winds at all). An approximate solution for obtaining the zero-lag cross-correlation corresponding to arbitrary spectral resolution directly from the zero-lag cross-correlation computed at full-resolution (good to within 2% at the scales of interest) is presented. Uncertainty in the observationally determined mean flux decrement of the Lyman-alpha forest was found to be the dominant source of systematic error; however, this is reduced significantly when considering correlation ratios. We describe a simple scheme for implementing our results, while mitigating systematic errors, in the context of a future application of the AP test.Comment: 20 page

Chandra X-ray Observatory Arcsecond Imaging of the Young, Oxygen-rich Supernova Remnant 1E0102.2-7219

We present observations of the young, Oxygen-rich supernova remnant 1E0102.2-7219 taken by the Chandra X-ray Observatory during Chandra's Orbital Activation and Checkout phase. The boundary of the blast wave shock is clearly seen for the first time, allowing the diameter of the remnant and the mean blast wave velocity to be determined accurately. The prominent X-ray bright ring of material may be the result of the reverse shock encountering ejecta; the radial variation of O VII vs. O VIII emission indicates an ionizing shock propagating inwards, possibly through a strong density gradient in the ejecta. We compare the X-ray emission to Australia Telescope Compact Array 6 cm radio observations (Amy and Ball) and to archival Hubble Space Telescope [O III] observations. The ring of radio emission is predominantly inward of the outer blast wave, consistent with an interpretation as synchrotron radiation originating behind the blast wave, but outward of the bright X-ray ring of emission. Many (but not all) of the prominent optical filaments are seen to correspond to X-ray bright regions. We obtain an upper limit of ~9e33 erg/s (3 sigma) on any potential pulsar X-ray emission from the central region.Comment: Accepted for pulication in Ap. J. Letters. 4 pages, 6 figures (one color figure). Formatted with emulateapj5. Revised to incorporate copyediting changes. High-resolution postscript (3.02MB) and tiff versions of the color figure are available from http://chandra.harvard.edu/photo/cycle1/0015multi/index.htm