Influence of Female Genital Cutting on Sexual Experience in Southern Ethiopia

Female genital cutting (FGC) is a persistent social norm in the Liben district of southern Ethiopia. This study explores whether the sexual experiences of married men and women differ by women's FGC status. Qualitative in-depth interviews were conducted with 28 women with different types of FGC (or no FGC) and 21 husbands. Compared to others, women with more severe FGC reported traumatic sexual experiences and decreased sexual desire. Nonetheless, participants largely endorsed FGC for daughters, revealing pressure to maintain the practice. Opportunities for change exist, as women and men recognized the sexual pleasure and healthy birth experiences of uncut women.     

Sexual Functioning in Spanish and Portuguese Young Adults: Initial Validation of the Arizona Sexual Experience Scale

Objectives: The authors conducted an initial validation of the Arizona Sexual Experience Scale (ASEX) and examined the sexual function of Spanish and Portuguese young adults. Methods: Participants were 523 Spanish and 595 Portuguese heterosexual young adults who completed a background questionnaire, the ASEX, and measures of sexual sensation seeking, excitation, and inhibition. Results: The ASEX showed good reliability and validity. Participants reported good sexual function. The most prevalent difficulties in men were related to desire and orgasm, and to orgasm and satisfaction in women. Conclusions: This is a psychometrically sound instrument to assess sexual functioning in Spanish and Portuguese young adults.     

The Impact of HIV Pre-exposure Prophylaxis (PrEP) Use on the Sexual Health of Men Who Have Sex with Men: A Qualitative Study in Seattle,WA

This study explores the impacts of HIV pre-exposure prophylaxis (PrEP) use on the sexual health of men who have sex with men (MSM). The authors conducted in-depth interviews with MSM who use PrEP (n = 14). Data was analyzed using interpretative phenomenological analysis. PrEP use reduced fear and shame associated with sex and facilitated greater sexual satisfaction and intimacy. Although participants generally viewed PrEP as empowering and beneficial, they also experienced PrEP-related stigma. The authors’ analysis emphasizes the importance of understanding the reasons MSM use PrEP and highlights opportunities for reducing harm and fostering sexual health among MSM who are using or considering PrEP.     

A Comparison of Correlation Structure Selection Penalties for Generalized Estimating Equations

Correlated data are commonly analyzed using models constructed using population-averaged generalized estimating equations (GEEs). The specification of a population-averaged GEE model includes selection of a structure describing the correlation of repeated measures. Accurate specification of this structure can improve efficiency, whereas the finite-sample estimation of nuisance correlation parameters can inflate the variances of regression parameter estimates. Therefore, correlation structure selection criteria should penalize, or account for, correlation parameter estimation. In this article, we compare recently proposed penalties in terms of their impacts on correlation structure selection and regression parameter estimation, and give practical considerations for data analysts. Supplementary materials for this article are available online.     

Approximate Bayesianity of Frequentist Confidence Intervals for a Binomial Proportion

The well-known Wilson and Agresti–Coull confidence intervals for a binomial proportion p are centered around a Bayesian estimator. Using this as a starting point, similarities between frequentist confidence intervals for proportions and Bayesian credible intervals based on low-informative priors are studied using asymptotic expansions. A Bayesian motivation for a large class of frequentist confidence intervals is provided. It is shown that the likelihood ratio interval for p approximates a Bayesian credible interval based on Kerman’s neutral noninformative conjugate prior up to O(n^{? 1}) in the confidence bounds. For the significance level α ? 0.317, the Bayesian interval based on the Jeffreys’ prior is then shown to be a compromise between the likelihood ratio and Wilson intervals. Supplementary materials for this article are available online.     

Approximate confidence intervals for the weighted kappa coefficient of a binary diagnostic test subject to a case–control design

Case–control design to assess the accuracy of a binary diagnostic test (BDT) is very frequent in clinical practice. This design consists of applying the diagnostic test to all of the individuals in a sample of those who have the disease and in another sample of those who do not have the disease. The sensitivity of the diagnostic test is estimated from the case sample and the specificity is estimated from the control sample. Another parameter which is used to assess the performance of a BDT is the weighted kappa coefficient. The weighted kappa coefficient depends on the sensitivity and specificity of the diagnostic test, on the disease prevalence and on the weighting index. In this article, confidence intervals are studied for the weighted kappa coefficient subject to a case–control design and a method is proposed to calculate the sample sizes to estimate this parameter. The results obtained were applied to a real example.     

New V control chart for the Maxwell distribution

Control charts have been popularly used as a user-friendly yet technically sophisticated tool to monitor whether a process is in statistical control or not. These charts are basically constructed under the normality assumption. But in many practical situations in real life this normality assumption may be violated. One such non-normal situation is to monitor the process variability from a skewed parent distribution where we propose the use of a Maxwell control chart. We introduce a pivotal quantity for the scale parameter of the Maxwell distribution which follows a gamma distribution. Probability limits and L-sigma limits are studied along with performance measure based on average run length and power curve. To avoid the complexity of future calculations for practitioners, factors for constructing control chart for monitoring the Maxwell parameter are given for different sample sizes and for different false alarm rate. We also provide simulated data to illustrate the Maxwell control chart. Finally, a real life example has been given to show the importance of such a control chart.     

Likelihood inference for the component lifetime distribution based on progressively censored parallel systems data

Point and interval estimators for the scale parameter of the component lifetime distribution of a k-component parallel system are obtained when the component lifetimes are assumed to be independently and identically exponentially distributed. We prove that the maximum likelihood estimator of the scale parameter based on progressively Type-II censored system lifetimes is unique and can be obtained by a fixed-point iteration procedure. In particular, we illustrate that the Newton–Raphson method does not converge for any initial value. Furthermore, exact confidence intervals are constructed by a transformation using normalized spacings and other component lifetime distributions including Weibull distribution are discussed.     

Managing Serials in an Institutional Repository: An Interview With Kay Teel

ABSTRACT

In this interview from March 2017, Kay Teel, metadata librarian for serials and arts resources at the Stanford University Libraries, discusses the issues involved in providing access to serials through an institutional repository.     

A closer look at de-aliasing effects using an efficient foldover technique

Foldover techniques are used to reduce the confounding when some important effects (usually lower order effects) cannot be estimated independently. This article develops an efficient foldover mechanism for symmetric or asymmetric designs, whether regular or nonregular. In this paper, we take the uniformity criteria (UC) as the optimality measures to construct the optimal combined designs (initial design plus its corresponding foldover design) which have better capability of estimating lower order effects. The relationship between any initial design and its combined design is studied. A comparison study between the combined designs via different UC is provided. Equivalence between any combined design and its complementary combined design is investigated, which is a very useful constraint that reduce the search space. Using our results as benchmarks, we can implement a powerful algorithm for constructing optimal combined designs. Our work covers as well as gives results better than recent works of about 20 articles in the last few years as special cases. So this article is a good reference for constructing effective designs.