Household wealth and adolescents' social-emotional functioning in schools.

This study attempts a two-part shift in educational research narrowly fixated on the socioeconomic determinants of student test-score performance. First, we focus on variations in how to measure wealth. Second, we move beyond achievement and focus on the wealth determinants of adolescents' social-emotional competencies. Using data from a nationally-representative sample of US eighth graders, we find that the correlation between wealth and social-emotional competencies varies according to how the partitions among the upper class, the middle and working classes, and the poor are defined. By emphasizing wealth in the production of classed social-emotional competencies not captured by test scores, our findings suggest that the growth of household wealth has a more salient effect for lower- and middle-class adolescents than the highest class which appears to have the least to gain, in terms of social-emotional competencies, from an increase in household wealth

Delay-Exponent of Bilayer Anytime Code

In this paper, we study the design and the delay-exponent of anytime codes over a three terminal relay network. We propose a bilayer anytime code based on anytime spatially coupled low-density parity-check (LDPC) codes and investigate the anytime characteristics through density evolution analysis. By using mathematical induction technique, we find analytical expressions of the delay-exponent for the proposed code. Through comparison, we show that the analytical delay-exponent has a close match with the delay-exponent obtained from numerical results.Comment: Accepted for presentation in ITW-2014. 5 Pages, 3 Figure

Finite Length Analysis of LDPC Codes

In this paper, we study the performance of finite-length LDPC codes in the waterfall region. We propose an algorithm to predict the error performance of finite-length LDPC codes over various binary memoryless channels. Through numerical results, we find that our technique gives better performance prediction compared to existing techniques.Comment: Submitted to WCNC 201

S-Track Stabilization of Heterotic de Sitter Vacua

We present a new mechanism, the S-Track, to stabilize the volume modulus S in heterotic M-theory flux compactifications along with the orbifold-size T besides complex structure and vector bundle moduli stabilization. The key dynamical ingredient which makes the volume modulus stabilization possible, is M5-instantons arising from M5-branes wrapping the whole Calabi-Yau slice. These are natural in heterotic M-theory where the warping shrinks the Calabi-Yau volume along S^1/Z_2. Combined with H-flux, open M2-instantons and hidden sector gaugino condensation it leads to a superpotential W which stabilizes S similar like a racetrack but without the need for multi gaugino condensation. Moreover, W contains two competing non-perturbative effects which stabilize T. We analyze the potential and superpotentials to show that it leads to heterotic de Sitter vacua with broken supersymmetry through non-vanishing F-terms.Comment: 16 pages, 2 figures; final PRD versio

Standard Model bundles of the heterotic string

We show how to construct supersymmetric three-generation models with gauge group and matter content of the Standard Model in the framework of non-simply-connected elliptically fibered Calabi-Yau manifolds Z. The elliptic fibration on a cover Calabi-Yau, where the model has 6 generations of SU(5) and the bundle is given via the spectral cover description, has a second section leading to the needed free involution. The relevant involution on the defining spectral data of the bundle is identified for a general Calabi-Yau of this type and invariant bundles are generally constructible.Comment: 23 pp; minor remarks adde

On Educational Outcomes in an Urban School District

Urban school districts face an enormous challenge. They are confronted with high levels of poverty and minority students who at high-risk for educational failure. To compound this, financial resources are lacking in improving these dire conditions. Thus, in a situation where increased budgetary support is no longer accessible, one question remains: What will make a difference? Chapter 1 suggests a first strategy. If district administrators or school principals could shift classroom composition to increase student achievement, then perhaps this managerial approach could improve urban education under extremely strict financial constraints. Using the framework of the education production function and two quasi-experiments, this investigation has identified status quo peer effects in Philadelphia’s elementary school classrooms over six years of observations. Holding fixed students and classrooms, Chapter 2 then asks what contributes to school effectiveness at the level of the institution. It does so by constructing two unique, quantifiable measures of school quality based on the empirical model from Chapter 1. The results indicate that institutional-level resources are significantly related to school quality across three categories (programs, personnel, and school environment) and within both testing subject areas. Based on the covariates analyzed in the first two chapters, Chapter 3 evaluates if and why there is significant variation in standardized testing performance for students in a single urban school district. Incorporating variables into a three-tiered hierarchical linear model of student achievement explains the majority of the between classroom and between school variance, though only half of the within classroom variance

A Stepwise Planned Approach to the Solution of Hilbert's Sixth Problem. III : Measurements and von Neumann Projection/Collapse Rule

Supmech, the universal mechanics developed in the previous two papers, accommodates both quantum and classical mechanics as subdisciplines (a brief outline is included for completeness); this feature facilitates, in a supmech based treatment of quantum measurements, an unambiguous treatment of the apparatus as a quantum system approximated well by a classical one. Taking explicitly into consideration the fact that observations on the apparatus are made when it has `settled down after the measurement interaction' and are restricted to macroscopically distinguishable pointer readings, the unwanted superpositions of (system + apparatus) states are shown to be suppressed; this provides a genuinely physics based justification for the (traditionally \emph{postulated}) von Neumann projection/collapse rule. The decoherence mechanism brought into play by the stated observational constraints is free from the objections against the traditional decoherence program.Comment: 29 pages; one section and two references added; results unchange

Resonator/zero-Qubit architecture for superconducting qubits

We analyze the performance of the Resonator/zero-Qubit (RezQu) architecture in which the qubits are complemented with memory resonators and coupled via a resonator bus. Separating the stored information from the rest of the processing circuit by at least two coupling steps and the zero qubit state results in a significant increase of the ON/OFF ratio and the reduction of the idling error. Assuming no decoherence, we calculate such idling error, as well as the errors for the MOVE operation and tunneling measurement, and show that the RezQu architecture can provide high fidelity performance required for medium-scale quantum information processing.Comment: 11 pages, 5 figure

Relativistic Tunneling Through Two Successive Barriers

We study the relativistic quantum mechanical problem of a Dirac particle tunneling through two successive electrostatic barriers. Our aim is to study the emergence of the so-called \emph{Generalized Hartman Effect}, an effect observed in the context of nonrelativistic tunneling as well as in its electromagnetic counterparts, and which is often associated with the possibility of superluminal velocities in the tunneling process. We discuss the behavior of both the phase (or group) tunneling time and the dwell time, and show that in the limit of opaque barriers the relativistic theory also allows the emergence of the Generalized Hartman Effect. We compare our results with the nonrelativistic ones and discuss their interpretation.Comment: 7 pages, 3 figures. Revised version, with a new appendix added. Slightly changes in the styles and captions of Figures 1 and 2. To appear in Physical Review

The Quality of Managed Care: Evidence from the Medical Literature

Gottfried and Sloan examine the empirical evidence, drawn from the medical literature, pertaining to the safety of managed care practices. They seek to ground the ongoing debate on the medical merits of managed care organizations in the science of clinical research