USING LINEAR PREDICTORS TO IMPUTE ALLELE FREQUENCIES FROM SUMMARY OR POOLED GENOTYPE DATA

Recently-developed genotype imputation methods are a powerful tool for detecting untyped genetic variants that affect disease susceptibility in genetic association studies. However, existing imputation methods require individual-level genotype data, whereas in practice it is often the case that only summary data are available. For example this may occur because, for reasons of privacy or politics, only summary data are made available to the research community at large; or because only summary data are collected, as in DNA pooling experiments. In this article, we introduce a new statistical method that can accurately infer the frequencies of untyped genetic variants in these settings, and indeed substantially improve frequency estimates at typed variants in pooling experiments where observations are noisy. Our approach, which predicts each allele frequency using a linear combination of observed frequencies, is statistically straight-forward, and related to a long history of the use of linear methods for estimating missing values (e.g. Kriging). The main statistical novelty is our approach to regularizing the covariance matrix estimates, and the resulting linear predictors, which is based on methods from population genetics. We find that, besides being both fast and flexible - allowing new problems to be tackled that cannot be handled by existing imputation approaches purpose-built for the genetic context - these linear methods are also very accurate. Indeed, imputation accuracy using this approach is similar to that obtained by state-of-the art imputation methods that use individual-level data, but at a fraction of the computational cost.     

A Preliminary Investigation of the Reinforcement Function of Signal Detections in Simulated Baggage Screening: Further Support for the Vigilance Reinforcement Hypothesis

The vigilance reinforcement hypothesis (VRH) asserts that errors in signal detection tasks are partially explained by operant reinforcement and extinction processes. VRH predictions were tested with a computerized baggage screening task. Our experiment evaluated the effects of signal schedule (extinction vs. variable interval 6 min) and visual field complexity (dial vs. baggage x-ray) on search behavior rates. There was a main effect for signal schedule [F (1, 20) = 14.0, p = .001, p_rep = 0.99], but no effects for field complexity or interaction. The VRH suggests that performance errors in visual screening work may be reduced through operant conditioning of search behaviors by intensive management of artificially planted signals.     

Irishness in Glasgow, 1863–70

In early November 1914 the German military authorities ordered the internment of all British male civilians aged between 17 and 55 then still resident in Germany. Over four thousand British subjects were affected by this measure. This article examines the domestic political background to the decision in favour of internment, focusing on the role of public opinion and of competing voices within the German war leadership. It also looks at attempts to negotiate the release and exchange of civilian prisoners after 1914. Internment was supported by the military and by most sections of the middle-class press. While partly a reaction to similar measures against Germans in Britain, it also reflected the government's growing frustration at the failure to achieve victory in the opening months of the war.     

Multivariate sufficient statistics using Kronecker products

We present a multivariate sufficient statistic using Kronecker products that dramatically increases computational efficiency in evaluating likelihood functions and/or posterior distributions. In particular, we examine the example of multivariate regression in a Bayesian setting. We compare the computation time for using the Gibbs sampler both with and without the sufficient statistic. We show that the difference in computation time grows quadratically with the number of covariates and products and linearly with the number of individuals. In the simulation study, speedup factors ranging from at least 20 times to almost 300 times were observed when using the Kronecker sufficient statistic.     

Anatomy of a Market Failure: NYSE Trading Suspensions (1974–1988)

A cross-sectional analysis of all trading suspensions that occurred during the period 1974–1988 in the New York Stock Exchange reveals that, though the desire to maintain price continuity remains an important motivation to suspend trade, inventory-imbalance fears are pronounced for large firms. Adverse-selection concerns afflict all news-related suspensions irrespective of firm size. Furthermore, we find substitutability among the various dimensions of liquidity: Although large- cap stocks have lower bid-ask spreads, they halt more often. A time series analysis shows that the resiliency of the exchange—its ability to absorb severe volatility shocks—has improved in this period.     

Audience Influence on EGM Gambling: The Protective Effects of Having Others Watch You Play

One component of social facilitation on gambling is the potential for an audience of people to observe the play of Electronic Gaming Machine (EGM) gamblers and influence their behaviour without participating directly in gambling themselves. An experiment was conducted with an audience of onlookers, purported to be students of research methods, taking notes while watching the participants play an EGM. Forty-three male and 82 female participants (N = 125), aged 18–79 (M = 49.2, SD = 15.6), played a laptop simulated 3-reel EGM using a $20 stake in three conditions: (1) alone, (2) watched by a simulated audience of six persons, or (3) watched by an audience of 26. Outcomes on the poker machine were rigged with a fixed sequence of five wins in the first 20 spins and indefinite losses thereafter. The results found smaller bet-sizes associated with larger audiences of onlookers, and this outcome is consistent with a hypothesized motivation to display more wins to the audience. Moreover, final payouts were greater in the audience conditions compared to the control, further suggesting that an audience may be a protective factor limiting player losses.     

Understanding Race and Ethnicity in Rural America1

Abstract Rural sociologists have an opportunity to make a significant contribution to the race and ethnic relations literature by focusing on the unique social position of minority communities in rural areas. Reservations, colonias, and rural African-Americans in the South are located in close proximity to the historic institutions established for their exploitation and oppression—slavery, for example. As such, these communities represent a legacy from which much can be learned. The potential impact of this work is readily seen in the context of the past contributions of rural sociologists. This discussion concludes with a review of the work of scholars studying race and ethnicity in rural areas in the early, middle, and later years of the discipline of rural sociology.     

Religion that strengthens democracy: An analysis of religious political strategies in Israel

Theory and Society -     

Sociopolitical Development and Vocational Expectations Among Lower Socioeconomic Status Adolescents of Color

The well‐documented aspiration‐expectation gap refers to lower socioeconomic status (SES) adolescents of color expecting to attain occupations with lower pay and status than the occupations to which they aspire. Sociopolitical inequity, such as structural racism and asymmetrical access to resources, may explain this gap. This article examines the capacity to cope with sociopolitical inequity (i.e., sociopolitical development) and its relationship to vocational expectations among this population. Analyses revealed that sociopolitical development was associated with higher vocational expectations and may contribute to reducing the vocational aspiration‐expectation gap among lower SES adolescents of color. Furthermore, career counseling, guidance, and psychosocial interventions may be augmented by incorporating sociopolitical development.