Axioms for consensus functions on the n-cube

An elementary general result is proved that allows for simple characterizations of well-known location/consensus functions (median, mean and center) on the n-cube. In addition, alternate new characterizations are given for the median and anti-median functions on the n-cube.Comment: 12 page

Differences in Dropout Rates as a Function of High School Size for Students in Poverty: A Texas Multiyear, Statewide Study

Child poverty in the United States, with regard to student achievement, has grave challenges for the children who face poverty (Scott & Pressman, 2013). Not only is living in poverty associated with lower academic achievement, but student poverty is also associated with lower rates of school completion (Borg, Borg, & Stranahan, 2012; Cooper & Crosnoe, 2007; Kena et al., 2015). Consequentially, students who do not complete high school are more likely to (a) serve time in prison, (b) need government assistance, and/or ( c) die at an earlier age (Messacar & Oreopoulos, 2013). With the increasing number of children who are living in poverty, child poverty is an issue that needs to be at the forefront of the educational agenda (Tienken, 2012)

Grade Span Configuration and Academic Performance for Students in Poverty: A Texas Multiyear Analysis

Grade-span configuration refers to the range of grades within a school (Coladarci & Hancock, 2002). The debate over the benefits of one grade span configuration over the other has ensued for decades (Howley, 2002). Specific questions in this debate are (a) Which grade span configuration is most cost effective?; (b) Which grade span configuration yields the best academic achievement?; and (c) Which grade span configuration best meets the social and emotional needs of middle level children? (Howley, 2002)

Optical absorption of divalent metal tungstates: Correlation between the band-gap energy and the cation ionic radius

We have carried out optical-absorption and reflectance measurements at room temperature in single crystals of AWO4 tungstates (A = Ba, Ca, Cd, Cu, Pb, Sr, and Zn). From the experimental results their band-gap energy has been determined to be 5.26 eV (BaWO4), 5.08 eV (SrWO4), 4.94 eV (CaWO4), 4.15 eV (CdWO4), 3.9-4.4 eV (ZnWO4), 3.8-4.2 eV (PbWO4), and 2.3 eV (CuWO4). The results are discussed in terms of the electronic structure of the studied tungstates. It has been found that those compounds where only the s electron states of the A2+ cation hybridize with the O 2p and W 5d states (e.g BaWO4) have larger band-gap energies than those where also p, d, and f states of the A2+ cation contribute to the top of the valence band and the bottom of the conduction band (e.g. PbWO4). The results are of importance in view of the large discrepancies existent in prevoiusly published data.Comment: 16 pages, 3 figures, 1 tabl

Fully distributed Bayesian optimization with stochastic policies

Bayesian optimization has become a popular method for high-throughput computing, like the design of computer experiments or hyperparameter tuning of expensive models, where sample efficiency is mandatory. In these applications, distributed and scalable architectures are a necessity. However, Bayesian optimization is mostly sequential. Even parallel variants require certain computations between samples, limiting the parallelization bandwidth. Thompson sampling has been previously applied for distributed Bayesian optimization. But, when compared with other acquisition functions in the sequential setting, Thompson sampling is known to perform suboptimally. In this paper, we present a new method for fully distributed Bayesian optimization, which can be combined with any acquisition function. Our approach considers Bayesian optimization as a partially observable Markov decision process. In this context, stochastic policies, such as the Boltzmann policy, have some interesting properties which can also be studied for Bayesian optimization. Furthermore, the Boltzmann policy trivially allows a distributed Bayesian optimization implementation with high level of parallelism and scalability. We present results in several benchmarks and applications that show the performance of our method

Breaking the Rayleigh-Plateau instability limit using thermocavitation within a droplet

We report on the generation of liquid columns that extend far beyond the traditional Rayleigh-Plateau instability onset. The columns are driven by the acoustic pressure wave emitted after bubble collapse. A high-speed video imaging device, which records images at a rate of up to 105 fps, was employed to follow their dynamics. These bubbles, commonly termed thermocavitation bubbles, are generated by focusing a midpower (275 mW) continuous wavelength laser into a highly absorbing liquid droplet. A simple model of the propagation of the pressure wavefront emitted after the bubble collapse shows that focusing the pressure wave at the liquid-air interface drives the evolution of the liquid columns. Control over the aspect ratio of the liquid column is realized by adjusting the cavitation bubble's size, beam focus position, and droplet volume. © 2013 by Begell House, Inc