The Optimal Single Copy Measurement for the Hidden Subgroup Problem

The optimization of measurements for the state distinction problem has recently been applied to the theory of quantum algorithms with considerable successes, including efficient new quantum algorithms for the non-abelian hidden subgroup problem. Previous work has identified the optimal single copy measurement for the hidden subgroup problem over abelian groups as well as for the non-abelian problem in the setting where the subgroups are restricted to be all conjugate to each other. Here we describe the optimal single copy measurement for the hidden subgroup problem when all of the subgroups of the group are given with equal a priori probability. The optimal measurement is seen to be a hybrid of the two previously discovered single copy optimal measurements for the hidden subgroup problem.Comment: 8 pages. Error in main proof fixe

What's the best way to screen for anxiety and panic disorders?

The GAD-7 has the best evidence and utility in the primary care setting for generalized anxiety disorder (strength of recommendation [SOR]: A), while the proprietary Quick PsychoDiagnostics Panel (QPD) has the best operating characteristics for panic disorder (SOR: B)

Including Systematic Uncertainties in Confidence Interval Construction for Poisson Statistics

One way to incorporate systematic uncertainties into the calculation of confidence intervals is by integrating over probability density functions parametrizing the uncertainties. In this note we present a development of this method which takes into account uncertainties in the prediction of background processes, uncertainties in the signal detection efficiency and background efficiency and allows for a correlation between the signal and background detection efficiencies. We implement this method with the Feldman & Cousins unified approach with and without conditioning. We present studies of coverage for the Feldman & Cousins and Neyman ordering schemes. In particular, we present two different types of coverage tests for the case where systematic uncertainties are included. To illustrate the method we show the relative effect of including systematic uncertainties the case of dark matter search as performed by modern neutrino tel escopes.Comment: 23 pages, 10 figures, replaced to match published versio

Association of collective attitudes and contraceptive practice in nine sub-Saharan African countries.

BACKGROUND: There is ample evidence that gender norms affect contraceptive practice; however, data are mostly qualitative with limited geographical scope. We investigated that association quantitatively using collective community-level attitudes towards premarital sex and wife-beating as proxies for gender norms. METHODS: Data came from nationally representative Demographic and Health Surveys (2005-2009) for women of reproductive age (15-49 years) in nine sub-Saharan African countries. Using multilevel logistic models, controlling for individual covariates and community-level indicators of women's empowerment, we assessed the community-level association of gender norms regarding premarital sex and wife-beating with individual contraception uptake and demand satisfied among fecund sexually active women. Norms were approximated as 'collective attitudinal norms' from female/male residents (aged 15-49 years) from the same community. We assessed the magnitude and significance of the community-level effects and attributed variance across communities. The same analysis was replicated for each country. RESULTS: In a fully-adjusted model with a pooled sample of 24?404 adolescent women, the odds of contraception use increased with a 1 standard deviation (SD) increase in the variation of collective permissive attitudes towards premarital sex of female (odds ratio (OR)?=?1.08, 95% confidence interval (CI)?=?1.02-1.15) and male (OR?=?1.11, 95% CI?=?1.05-1.17) peers (15-24 years), while odds of contraceptive use declined by 10% (OR?=?0.90, 95% CI?=?0.85-0.96) with collective accepting attitudes towards wife-beating of women aged 15-49 years. Similar results were found in separate models that controlled for adults' permissive attitudes towards premarital sex. The community-level attributed variance (V2?=?1.62, 95% CI?=?1.45-1.80) represented 33% (intra-class correlation (ICC)?=?33.0, 95% CI?=?30.0-35.4) of the total variation of contraception use, and attitudes towards premarital sex and violence jointly explained nearly 26% of that V2 variance. The community-level shared of attributed variation of contraceptive use varied significantly across countries, from 3.5% in Swaziland (ICC?=?3.5, 95% CI?=?0.8-13.7) to 60.2% in Nigeria (OR?=?60.2, 95% CI?=?56.0-64.2). CONCLUSIONS: Overall, significant positive associations of collective permissive attitudes of both adolescent and adult women towards premarital sex were found for use of, and demand for, contraception, whereas collective accepting attitudes towards wife-beating were negatively associated with the use and demand for contraception. Ours is the first study to define quantitatively the influence of proxies for gender norms at the community level on women's family planning decisions. These findings offer new insights for understanding the role of sex-related attitudes and norms as important factors in shaping contraceptive practices and improving the effectiveness of family planning policies by targeting individuals as well as their groups of influence

Optical Properties of Deep Ice at the South Pole - Absorption

We discuss recent measurements of the wavelength-dependent absorption coefficients in deep South Pole ice. The method uses transit time distributions of pulses from a variable-frequency laser sent between emitters and receivers embedded in the ice. At depths of 800 to 1000 m scattering is dominated by residual air bubbles, whereas absorption occurs both in ice itself and in insoluble impurities. The absorption coefficient increases approximately exponentially with wavelength in the measured interval 410 to 610 nm. At the shortest wavelength our value is about a factor 20 below previous values obtained for laboratory ice and lake ice; with increasing wavelength the discrepancy with previous measurements decreases. At around 415 to 500 nm the experimental uncertainties are small enough for us to resolve an extrinsic contribution to absorption in ice: submicron dust particles contribute by an amount that increases with depth and corresponds well with the expected increase seen near the Last Glacial Maximum in Vostok and Dome C ice cores. The laser pulse method allows remote mapping of gross structure in dust concentration as a function of depth in glacial ice.Comment: 26 pages, LaTex, Accepted for publication in Applied Optics. 9 figures, not included, available on request from [email protected]

A First Search for Cosmogenic Neutrinos with the ARIANNA Hexagonal Radio Array

The ARIANNA experiment seeks to observe the diffuse flux of neutrinos in the 10^8 - 10^10 GeV energy range using a grid of radio detectors at the surface of the Ross Ice Shelf of Antarctica. The detector measures the coherent Cherenkov radiation produced at radio frequencies, from about 100 MHz to 1 GHz, by charged particle showers generated by neutrino interactions in the ice. The ARIANNA Hexagonal Radio Array (HRA) is being constructed as a prototype for the full array. During the 2013-14 austral summer, three HRA stations collected radio data which was wirelessly transmitted off site in nearly real-time. The performance of these stations is described and a simple analysis to search for neutrino signals is presented. The analysis employs a set of three cuts that reject background triggers while preserving 90% of simulated cosmogenic neutrino triggers. No neutrino candidates are found in the data and a model-independent 90% confidence level Neyman upper limit is placed on the all flavor neutrino+antineutrino flux in a sliding decade-wide energy bin. The limit reaches a minimum of 1.9x10^-23 GeV^-1 cm^-2 s^-1 sr^-1 in the 10^8.5 - 10^9.5 GeV energy bin. Simulations of the performance of the full detector are also described. The sensitivity of the full ARIANNA experiment is presented and compared with current neutrino flux models.Comment: 22 pages, 22 figures. Published in Astroparticle Physic

Computational Indistinguishability between Quantum States and Its Cryptographic Application

We introduce a computational problem of distinguishing between two specific quantum states as a new cryptographic problem to design a quantum cryptographic scheme that is "secure" against any polynomial-time quantum adversary. Our problem, QSCDff, is to distinguish between two types of random coset states with a hidden permutation over the symmetric group of finite degree. This naturally generalizes the commonly-used distinction problem between two probability distributions in computational cryptography. As our major contribution, we show that QSCDff has three properties of cryptographic interest: (i) QSCDff has a trapdoor; (ii) the average-case hardness of QSCDff coincides with its worst-case hardness; and (iii) QSCDff is computationally at least as hard as the graph automorphism problem in the worst case. These cryptographic properties enable us to construct a quantum public-key cryptosystem, which is likely to withstand any chosen plaintext attack of a polynomial-time quantum adversary. We further discuss a generalization of QSCDff, called QSCDcyc, and introduce a multi-bit encryption scheme that relies on similar cryptographic properties of QSCDcyc.Comment: 24 pages, 2 figures. We improved presentation, and added more detail proofs and follow-up of recent wor