When the Shoe is on the Other Foot: Experimental Evidence on Valuation Disparities

The method of elicitation has an important effect on valuations. We investigate the effect of perspective on decision makersâ?? elicited values. We conduct experimental sessions in which participants act as sellers or buyers and replicate the disparity between willingness to accept and willingness to pay: sellers want to collect more and buyers want to pay less. We conduct additional sessions in which endowed decision makers provide values that are used to determine a price at which anonymous others transact. In these sessions, decision makersâ?? experimental earnings are not affected by valuations, but rather determined by their endowment. Decision makers appear to consider their standing relative to anonymous others in providing valuations, i.e., decision makersâ?? endowments affect their valuations. The results indicate that the disparity between willingness to accept and willingness to pay disappears when decision makersâ?? endowment ensures that they are at least as well off as anonymous others.

When the shoe is on the other foot: experimental evidence on evaluation disparities

Research provides evidence that the method chosen to elicit value has an important effect on a person’s valuation. We hypothesize that role has a crucial effect on decision makers’ elicited values: Buyers prefer to pay less and sellers prefer to collect more. We conduct experimental sessions and replicate the disparity between willingness to pay and willingness to accept. We conduct additional sessions in which role is stripped away: Endowed decision makers provide values that are used to determine a price at which anonymous others transact. Importantly, decision makers’ earnings in the experiment are not affected by the elicited values, but the endowments influence decision makers’ valuations. Our findings suggest that decision makers consider their relative standing, in comparison to anonymous others, in providing valuations. The disparity between willingness to pay and willingness to accept disappears when decision makers’ endowments ensure that they are at least as well off as other participants.

Integrating Dynamics and Wear Modelling to Predict Railway Wheel Profile Evolution

The aim of the work described was to predict wheel profile evolution by integrating multi-body dynamics simulations of a wheelset with a wear model. The wear modelling approach is based on a wear index commonly used in rail wear predictions. This assumes wear is proportional to Tγ, where T is tractive force and γ is slip at the wheel/rail interface. Twin disc testing of rail and wheel materials was carried out to generate wear coefficients for use in the model. The modelling code is interfaced with ADAMS/Rail, which produces multi-body dynamics simulations of a railway wheelset and contact conditions at the wheel/rail interface. Simplified theory of rolling contact is used to discretise the contact patches produced by ADAMS/Rail and calculate traction and slip within each. The wear model combines the simplified theory of rolling contact, ADAMS/Rail output and the wear coefficients to predict the wear and hence the change of wheel profile for given track layouts

Drawing Graphs within Restricted Area

We study the problem of selecting a maximum-weight subgraph of a given graph such that the subgraph can be drawn within a prescribed drawing area subject to given non-uniform vertex sizes. We develop and analyze heuristics both for the general (undirected) case and for the use case of (directed) calculation graphs which are used to analyze the typical mistakes that high school students make when transforming mathematical expressions in the process of calculating, for example, sums of fractions

The mean and standard deviation of the distribution of group assembly sums

An interesting problem in linear programming is the group assembly problem which is mathematically equivalent to the general transportation problem of economics. Computer programs designed for the determination of exact and approximate optimal group assemblies have been available for some time. This paper presents formulas for the mean and squared standard deviation of the distribution of all possible group assembly sums. Computational techniques are presented and the results are related to those of the analysis of variance of a k -factor problem with n levels of each factor.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45717/1/11336_2005_Article_BF02289606.pd

A side-by-side comparison of Daya Bay antineutrino detectors

The Daya Bay Reactor Neutrino Experiment is designed to determine precisely the neutrino mixing angle θ_(13) with a sensitivity better than 0.01 in the parameter sin^22θ_(13) at the 90% confidence level. To achieve this goal, the collaboration will build eight functionally identical antineutrino detectors. The first two detectors have been constructed, installed and commissioned in Experimental Hall 1, with steady data-taking beginning September 23, 2011. A comparison of the data collected over the subsequent three months indicates that the detectors are functionally identical, and that detector-related systematic uncertainties are smaller than requirements

Improved measurement of electron antineutrino disappearance at Daya Bay

We report an improved measurement of the neutrino mixing angle θ_(13) from the Daya Bay Reactor Neutrino Experiment. We exclude a zero value for sin^22θ_(13) with a significance of 7.7 standard deviations. Electron antineutrinos from six reactors of 2.9 GW_(th) were detected in six antineutrino detectors deployed in two near (flux-weighted baselines of 470 m and 576 m) and one far (1648 m) underground experimental halls. Using 139 days of data, 28909 (205308) electron antineutrino candidates were detected at the far hall (near halls). The ratio of the observed to the expected number of antineutrinos assuming no oscillations at the far hall is 0.944±0.007(stat.)±0.003(syst.). An analysis of the relative rates in six detectors finds sin^22θ_(13)=0.089±0.010(stat.)±0.005(syst.) in a three-neutrino framework

The detailed method of optimal regions

The detailed method of optimal regions is an extended form of the method of optimal regions which has been found effective in solving the personnel classification problem when the number of job categories is small. The automatic determination of the successive values of the v i , made possible by the more exact techniques of the detailed method, provide easier solutions for the more complex problems and provide solutions, which, for the most part, can be mechanized. In a sense the detailed method of optimal regions is more than a detailed form of the method of optimal regions. It is essentially a method of transformations by which the original matrix is reduced to a matrix from which the solution is easily obtained.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45700/1/11336_2005_Article_BF02289208.pd

Surface Hydrogen Modeling of Super Soft X-ray Sources: Are They Supernova Ia Progenitors?

Nova explosions occur on the white dwarf (WD) component of a Cataclysmic Variable stellar system which is accreting matter lost by a companion. A Type Ia supernova explosion is thought to result when a WD, in a similar binary configuration, grows in mass to the Chandrasekhar Limit. Here, we present calculations of accretion of Solar matter, at a variety of mass accretion rates, onto hot ($2.3 \times 10^{5}$K), luminous (30L$_\odot$), massive (1.25M$_\odot$, 1.35M$_\odot$) Carbon-Oxygen WDs. In contrast to our nova simulations where the WD has a low initial luminosity and a thermonuclear runaway (TNR) occurs and ejects material, these simulations do not eject material (or only a small fraction of the accreted material) and the WD grows in mass. A hydrogen TNR does not occur because hydrogen fuses to helium in the surface layers, and we call this process Surface Hydrogen Burning (SHB). As the helium layer grows in mass, it gradually fuses either to carbon and oxygen or to more massive nuclei depending on the WD mass and mass accretion rate. If such a WD were to explode in a SN Ia event, therefore, it would show neither hydrogen nor helium in its spectrum as is observed. Moreover, the luminosities and effective temperatures of our simulations agree with the observations of some of the Super Soft X-ray Binary Sources and, therefore, our results strengthen previous speculation that some of them (CAL 83 and CAL 87 for example) are probably progenitors of SN Ia explosions. Finally, we have achieved SHB for values of the mass accretion rate that almost span the observed values of the Cataclysmic Variables.Comment: Accepted by APJL, 4 pages, 1 figure, LaTex (uses emulateapj.sty