Estimating spillovers using imprecisely measured networks

In many experimental contexts, whether and how network interactions impact the outcome of interest for both treated and untreated individuals are key concerns. Networks data is often assumed to perfectly represent these possible interactions. This paper considers the problem of estimating treatment effects when measured connections are, instead, a noisy representation of the true spillover pathways. We show that existing methods, using the potential outcomes framework, yield biased estimators in the presence of this mismeasurement. We develop a new method, using a class of mixture models, that can account for missing connections and discuss its estimation via the Expectation-Maximization algorithm. We check our method's performance by simulating experiments on real network data from 43 villages in India. Finally, we use data from a previously published study to show that estimates using our method are more robust to the choice of network measure

Adversity-related experiences are essential for Olympic success: additional evidence and considerations

Drawing on Hardy et al.'s study as the target article, in this commentary, we focus on the adversity-related experiences and consequences of the Olympic and/or World champions that they sampled. With this in mind, we divide the narrative into two main sections. In the first section, we explore the association between adversity-related experiences and Olympic success, and provide additional evidence in support of the notion that adversity-related experiences are essential for success at the highest level of sport. In the second section, we discuss the role of adversity-related experiences in Olympic success considering a series of important psychosocial processes that are required for superior performance. In ending, we reflect on the salient (contentious and ethical) issues in the study and practice of adversity-related experiences and sport performance. We hope that our commentary adds to the extant literature and is useful for future study and practice in performance sport

Nancy Meleski Collection - Accession 1566

The Nancy Meleski Collection contains a family bible with names of people who got married, were born, and died, a family dictionary that contains names of people and towns, and a collection of sheet music for vocals, violin, and piano. Names and places listed in the family bible are: Moses F. Hardy, Amanda Kineeskern, Seward Valley, New York, Stefhen P. Brewster, Julia Holly, Amanda Hardy, William Eben Hardy, Parley Elmer Hardy, Katharine Melinda Brewster, and Rhoby Jennings. People and places listed in the family dictionary are: Volney, New York, Schroeppel, New York, Chauncy Morgan, Palermo Morgan, Albert Morgan, Richard Holly, and Marie Holly Woods.https://digitalcommons.winthrop.edu/manuscriptcollection_findingaids/2625/thumbnail.jp

Projections for measuring the size of the solar core with neutrino-electron scattering

We quantify the amount of data needed in order to measure the size and position of the $^8$B neutrino production region within the solar core, for experiments looking at elastic scattering between electrons and solar neutrinos. The directions of the electrons immediately after scattering are strongly correlated with the incident directions of the neutrinos, however this is degraded significantly by the subsequent scattering of these electrons in the detector medium. We generate distributions of such electrons for different neutrino production profiles, and use a maximum likelihood analysis to make projections for future experimental sensitivity. We find that with approximately 20 years worth of data the Super Kamiokande experiment could constrain the central radius of the shell in which $^8$B neutrinos are produced to be less than 0.22 of the total solar radius at 95% confidence.Comment: 5 pages, 2 figures. Matches version accepted to PRL. Improved 2D analysis and results discussio

Superfluid Density in a Highly Underdoped YBCO Superconductor

The superfluid density rho_s(T) = 1/lambda^2(T) has been measured at 2.64 GHz in highly underdoped YBCO, at 37 dopings with T_c between 3 K and 17 K. Within limits set by the transition width Delta T_c ~ 0.4 K, rho_s(T) shows no evidence of critical fluctuations as T goes to T_c, with a mean-field-like transition and no indication of vortex unbinding. Instead, we propose that rho_s displays the behaviour expected for a quantum phase transition in the (3 + 1)-dimensional XY universality class, with rho_s0 ~ (p - p_c), T_c ~ (p - p_c)^1/2 and rho_s(T) ~ (T_c - T)^1 as T goes to T_c.Comment: 4 pages, 5 figures; final version of pape

Apparatus for high resolution microwave spectroscopy in strong magnetic fields

We have developed a low temperature, high-resolution microwave surface impedance probe that is able to operate in high static magnetic fields. Surface impedance is measured by cavity perturbation of dielectric resonators, with sufficient sensitivity to resolve the microwave absorption of sub-mm-sized superconducting samples. The resonators are constructed from high permittivity single-crystal rutile (TiO2) and have quality factors in excess of 10^6. Resonators with such high performance have traditionally required the use of superconducting materials, making them incompatible with large magnetic fields and subject to problems associated with aging and power-dependent response. Rutile resonators avoid these problems while retaining comparable sensitivity to surface impedance. Our cylindrical rutile resonators have a hollow bore and are excited in TE_01(n-d) modes, providing homogeneous microwave fields at the center of the resonator where the sample is positioned. Using a sapphire hot-finger technique, measurements can be made at sample temperatures in the range 1.1 K to 200 K, while the probe itself remains immersed in a liquid helium bath at 4.2 K. The novel apparatus described in this article is an extremely robust and versatile system for microwave spectroscopy, integrating several important features into a single system. These include: operation at high magnetic fields; multiple measurement frequencies between 2.64 GHz and 14.0 GHz in a single resonator; excellent frequency stability, with typical drifts < 1 Hz per hour; the ability to withdraw the sample from the resonator for background calibration; and a small pot of liquid helium separate from the external bath that provides a sample base temperature of 1.1 K.Comment: 10 pages, 5 figure

Bolometric technique for high-resolution broadband microwave spectroscopy of ultra-low-loss samples

A novel low temperature bolometric method has been devised and implemented for high-precision measurements of the microwave surface resistance of small single-crystal platelet samples having very low absorption, as a continuous function of frequency. The key to the success of this non-resonant method is the in-situ use of a normal metal reference sample that calibrates the absolute rf field strength. The sample temperature can be controlled independently of the 1.2 K liquid helium bath, allowing for measurements of the temperature evolution of the absorption. However, the instrument's sensitivity decreases at higher temperatures, placing a limit on the useful temperature range. Using this method, the minimum detectable power at 1.3 K is 1.5 pW, corresponding to a surface resistance sensitivity of $\approx$1 $\mu\Omega$ for a typical 1 mm$\times$1 mm platelet sample.Comment: 13 pages, 12 figures, submitted to Review of Scientific Instrument

Policing vulnerability through building community connections

Most people who come into contact with the Police Service can be described, in some way or other, as vulnerable. Victims, offenders, witnesses, and bystanders are all exposed to social conflict and attempts by the police to restore order. Thus, while vulnerability is context-specific it is largely defined via deficit frameworks that view individuals and groups as marginalized or disadvantaged and requiring immediate intervention. This framework is expensive, risk-averse, and often counter-productive for police and associated agencies. The policy push for demand reduction amongst policing agencies offers an opportunity to re-evaluate this approach and to identify and mobilize local assets that can support vulnerable populations. This article draws on the literature on addictions and recovery to explore the networks of support available to vulnerable populations and the potential mechanisms this presents for the development of assertive linkages, community capacity, and self-policing