Asperger’s Syndrome and the Decoding of Boredom,Interest, and Disagreement from Body Posture

Twenty Asperger’s Syndrome (AS) participants were compared with 20 matched neurotypical controls in their decoding of postural cues of boredom, interest, and disagreement. On a nonverbal matching task, the AS group performed as accurately as the controls, whereas on a verbal labeling task, AS participants made significantly more mistakes in labeling bored postures. Response times of the AS group were significantly slower than controls in their judgments of all three attitudes on both tasks, with the exception only of disagreeing postures on the verbal labeling task. It was hypothesized that these slower response times may reflect a feature-based cognitive processing style by AS participants. Proposed practical recommendations are to train AS individuals in the recognition of boredom, and to improve the speed with which they can recognize different attitudes.     

The mean of linear signed rank statistics under alternatives

An expression is presented for the mean of a linear signed rank statistic for the one sample location model. Several examples are given to illustrate its application.     

Skill and education effects on earnings in 18 Countries: The role of national educational institutions

This study investigates whether the mechanisms why education is rewarded vary across countries. Do educational institutions affect the likelihood that support for a particular mechanism is found? Combining IALS survey data and OECD statistics on educational institutions, it was shown that the effect of measured skill on earnings - controlled for educational attainment - is lower in countries where educational institutions produce skills relevant for work through the vocational system. This indicates that the human capital perspective on education works particularly well in vocationally oriented educational systems, as the skills generated in education are strongly overlapping with the skills that are rewarded. An alternative mechanism sees education as a means for social closure through credentialization. Under the credentialization model, education is not primarily rewarded for the productivity-enhancing skills it entails, but rather for reasons unrelated to productivity. Following this theory education is used for selection into the organization, after which directly observable skills are determining wages. Assuming that a strongly differentiated educational system creates boundaries between social groups, it is hypothesized that strongly differentiated systems lead to stronger measured skill effects. We do not find support for this hypothesis.     

Theorizing the lesbian hashtag: Identity,community, and the technological imperative to name the sexual self

This analysis integrates poststructuralist and symbolic interactionist approaches to the self by incorporating the insights of science and technology studies regarding categorization processes. While the advent of the Internet has freed many individuals from geographical constraints on community formation, the architectures of online platforms produce a technological imperative to name aspects of the self with words. Using sexual identity hashtags on Instagram (e.g., #lesbian) thus performs paradoxical functions: the hashtag both enables the construction of a sexual identity within an affirming community and also reinforces the power relations that compel individuals to name and account for their sexual selves. By illustrating one way sexual identities function in the online lives of young women, this research complicates other scholars' findings that the salience of sexual identity categories is decreasing.     

The Probability of Teenage Parenthood: Parental Predictions and Their Accuracy

Teenage parenthood is an often-discussed topic in family economics since it has been shown to affect many outcomes for the teen, child, and household. Using a nationally representative longitudinal panel of American teenagers and their parents, two questions related to the probability of teenage parenthood are examined. First, how do predictions of this occurrence made by the teenager’s parents vary across the population? Second, how does the accuracy of these predictions vary? The actual prevalence and variance of teenage parenthood are also examined, and the determinants of its occurrence are estimated. Among other results, expectations and their accuracy are found to differ substantially across socioeconomic status and some demographics such as race and religion. The average American parent underestimates the probability their child will become a teen parent by only a small amount, but within certain demographic groups this outcome is considerably underestimated, and in others it is overestimated. These differences help explain the variability in teen parenthood effects, and more broadly, the analysis serves as a test of parents’ ability to judge their childrens’ future outcomes.     

Diffusive nested sampling

We introduce a general Monte Carlo method based on Nested Sampling (NS), for sampling complex probability distributions and estimating the normalising constant. The method uses one or more particles, which explore a mixture of nested probability distributions, each successive distribution occupying ∼e ⁻¹ times the enclosed prior mass of the previous distribution. While NS technically requires independent generation of particles, Markov Chain Monte Carlo (MCMC) exploration fits naturally into this technique. We illustrate the new method on a test problem and find that it can achieve four times the accuracy of classic MCMC-based Nested Sampling, for the same computational effort; equivalent to a factor of 16 speedup. An additional benefit is that more samples and a more accurate evidence value can be obtained simply by continuing the run for longer, as in standard MCMC.     

CUSUM Control Charts for Multivariate Poisson Distribution

A cumulative sum control chart for multivariate Poisson distribution (MP-CUSUM) is proposed. The MP-CUSUM chart is constructed based on log-likelihood ratios with in-control parameters, Θ₀, and shifts to be detected quickly, Θ₁. The average run length (ARL) values are obtained using a Markov Chain-based method. Numerical experiments show that the MP-CUSUM chart is effective in detecting parameter shifts in terms of ARL. The MP-CUSUM chart with smaller Θ₁ is more sensitive than that with greater Θ₁ to smaller shifts, but more insensitive to greater shifts. A comparison shows that the proposed MP-CUSUM chart outperforms an existing MP chart.     

Mean square error comparison among variance estimators with known coefficient of variation

The improved estimators for the population parameters were considered by several statisticians under various conditions. Recently Laheetharan and Wijekoon (Improved estimation of the population parameters when some additional information is available. Stat Papers doi:, 2008) demonstrated a generalized procedure for obtaining optimal shrunken estimators, and derived such estimators for both population mean and variance when coefficient of variation is known. In this article the mean square errors of those estimators were compared, and a numerical illustration was done using the scaled mean square error loss as used by Kanefuji and Iwase (Stat Papers 39:377–388, 1998) to understand the efficiency of the estimators with increasing sample size.