Are simple tests of son preference useful? An evaluation using data from Vietnam

Son preference is widespread although not universal. Where it occurs it may lead to higher fertility rates. Ideally son preference should be measured in the context of a hazards or parity progression model of fertility, or a logistic model of contraceptive use. Such models require large amounts of survey data, particularly to measure the covariates. Can son preference be discerned reliably using tests which rely on more limited information? The answer is yes, based on applying eight simple tests to data from the Vietnam Living Standards Survey of 1992–93 and comparing the outcomes with the benchmark results from fuller models. Some, but not all, of the simpler tests accurately measure son preference, including estimating a simple hazards or progression parity model, the unisex sibship test, and the sibling differentials test. Received: 28 September 1995 / Accepted: 2 January 1997     

Improving an exact approach for solving separable integer quadratic knapsack problems

We consider the specially structured (pure) integer Quadratic Multi-Knapsack Problem (QMKP) tackled in the paper “Exact solution methods to solve large scale integer quadratic knapsack problems” by D. Quadri, E. Soutif and P. Tolla (2009), recently appeared on this journal, where the problem is solved by transforming it into an equivalent 0–1 linearized Multi-Knapsack Problem (MKP). We show that, by taking advantage of the structure of the transformed (MKP), it is possible to derive an effective variable fixing procedure leading to an improved branch-and-bound approach. This procedure reduces dramatically the resulting linear problem size inducing an impressive improvement in the performances of the related branch and bound approach when compared to the results of the approach proposed by D. Quadri, E. Soutif and P. Tolla.     

WebStress: a web interface to explore a multidatabase bibliographic corpus on occupational stress

A bibliographic study on a multidisciplinary subject, such as occupational stress, requires a multidatabase query facility. Given this, we searched eight databases belonging to different fields (medicine, psychology, etc.) and from different countries. Thus, more than 26000 references on occupational stress were gathered. A bibliographic corpus of this sort is unusable because of the heterogeneous format of the records and the number of duplicate entries. Considering the limitations of commercial programs, we have developed a system, called WebStress, for reformatting the data and removing duplicates. The huge number of references and the research needs of updating and searching have necessitated the addition of several other functions to WebStress. Therefore WebStress comprises a web interface that makes it possible to search the corpus with advanced features (using clustering, a specialized thesaurus on stress and Boolean queries). In addition to the usual bibliographic queries on a specific database such as Medline, WebStress provides bibliometric analysis of the corpus, which might contribute to a detailed analysis on occupational stress in order to highlight the networks of researchers and to find the main topics studied in this area. WebStress is not yet available to researchers in general. It is being further developed, and also permission needs to be obtained from the eight commercial bibliographic databases that it consults.     

Disentangling the Influence of Value Predispositions and Risk/Benefit Perceptions on Support for Nanotechnology Among the American Public

Using nanotechnology as a case study, this article explores (1) how people's perceptions of benefits and risks are related to their approval of nanotechnology, (2) which information‐processing factors contribute to public risk/benefit perceptions, and (3) whether individuals’ predispositions (i.e., deference to scientific authority and ideology) may moderate the relationship between cognitive processing and risk perceptions of the technology. Results indicate that benefit perceptions positively affect public support for nanotechnology; perceptions of risk tend to be more influenced by systematic processing than by heuristic cues, whereas both heuristic and systematic processing influence benefit perceptions. People who are more liberal‐minded tend to be more affected by systematic processing when thinking about the benefits of nanotechnology than those who are more conservative. Compared to less deferent individuals, those who are more deferent to scientific authority tend to be less influenced by systematic processing when making judgments about the benefits and risks of nanotechnology. Implications are discussed.     

Improving quality at the point of service

The authors provide a research-based construct of youth program quality that differentiates safety, support, interaction, and engagement, four important issues for practitioners working with youth in the middle years. They describe two tools that have helped direct staff to be intentional about creating offerings that are appropriate for early adolescents: the focusing idea of point-of-service quality and the technology of observational assessment. They describe how these tools can be used to create cultures of accountability and intentionality that extend across program levels.     

Estimation of the mean of a spherically symmetric distribution with constraints on the norm

The authors consider the problem of estimating, under quadratic loss, the mean of a spherically symmetric distribution when its norm is supposed to be known and when a residual vector is available. They give a necessary and sufficient condition for the optimal James‐Stein estimator to dominate the usual estimator. Various examples are given that are not necessarily variance mixtures of normal distributions. Consideration is also given to an alternative class of robust James‐Stein type estimators that take into account the residual vector. A more general domination condition is given for this class.     

Ties in one block comparison experiments: a generalization of the Mallows–Bradley–Terry ranking model

This study is concerned with the extension of the Mallows–Bradley–Terry ranking model for one block comparison consisting of all the items of interest to situations which allow an expression of no preference. We consider a modification of the Mallows–Bradley–Terry ranking model by introducing an additional parameter, called an index of discrimination, in the model. This permits ties in the model. The maximum likelihood estimates of the parameters are found using a Maximization–Minimization algorithm: the evaluation of the mathematical expectations involved in the log-likelihood equation is obtained by generating samples of Monte Carlo Markov chain from the stationary distribution. In addition, a simulation study for asymptotic properties assessment has been made. The proposed method is applied to analyze data election.     

The effect of comment moderation on perceived bias in science news

Uncivil comments following online news articles about issues of science and technology have been shown to lead to biased interpretations of the news content itself. Using an experiment embedded in a nationally representative survey, we provide evidence that cues about comment moderation ? even without any change in the comments themselves ? have the potential to alleviate this so-called nasty effect. Participants exposed to uncivil comments that appear in a moderated environment were less likely to perceive bias in the news article itself. Importantly, perceptions of bias among respondents exposed to the uncivil, moderated stimulus were comparable to those of respondents who viewed both moderated and unmoderated civil comments. Our results suggest that visible cues about comment moderation are a potentially valuable endeavor for news organizations, especially in an age of declining profit margins.