An Efficient MCMC Algorithm to Sample Binary Matrices with Fixed Marginals

Uniform sampling of binary matrices with fixed margins is known as a difficult problem. Two classes of algorithms to sample from a distribution not too different from the uniform are studied in the literature: importance sampling and Markov chain Monte Carlo (MCMC). Existing MCMC algorithms converge slowly, require a long burn-in period and yield highly dependent samples. Chen et al. developed an importance sampling algorithm that is highly efficient for relatively small tables. For larger but still moderate sized tables (300×30) Chen et al.’s algorithm is less efficient. This article develops a new MCMC algorithm that converges much faster than the existing ones and that is more efficient than Chen’s algorithm for large problems. Its stationary distribution is uniform. The algorithm is extended to the case of square matrices with fixed diagonal for applications in social network theory. I am indebted to my colleague Gunter Maris for his suggestion to add a Metropolis–Hastings step as the finishing touch of the algorithm.     

Some Weakened Gödelian Ontological Systems

We describe a KB Gödelian ontological system, and some other weak systems, in a fully formal way using theory of types and natural deduction, and present a completeness proof in its main and specific parts. We technically and philosophically analyze and comment on the systems (mainly with respect to the relativism of values) and include a sketch of some connected aspects of Gödel's relation to Kant.     

Comprehension of reversible relative clauses in specifically language impaired and normally developing Greek children

This paper aims to investigate the syntactic comprehension of reversible relative clauses in a group of eight Greek children with specific language impairment (SLI) and two control groups of normally developing children matched on chronological and language age, respectively. An experiment using an acting out procedure was undertaken. Group analysis revealed that SLI children's performance is qualitatively different than that of both control groups. Interpreting the data, processes involved in syntactic comprehension are taken into consideration. It is claimed that processing demands impede SLI children's performance due to a deficit in their competence grammar.     

Identity and Engagement among Political Independents in America

Political behavior among independents has been documented for decades, yet we are left with limited insight into their political engagement. What, if anything, motivates independents to engage in politics? In this study, I apply psychological theories of attitude importance to explain high variation in political‐engagement levels among independents. Using two recent datasets, I find engagement levels are comparable across independents and partisans, yet predictors of their engagement differ substantially. Ideological strength predicts engagement for partisans—but not for independents. Instead, my data show that independents' engagement is best predicted by the importance they place on their independent identity. These data provide evidence that independence is a meaningful political identity and that identity importance is a key to explaining what motivates the independent voter to engage with politics.     

The relative importance of psychopathy-related traits in predicting impersonal sex and hostile masculinity

This paper reports the relative contributions of several facets of subclinical psychopathy (i.e., callous affect, erratic lifestyle, interpersonal manipulation), subclinical narcissism (i.e., entitlement, exploitation), and trait aggression (i.e., anger) to the prediction of four enduring attitudes towards women and sexual assault (i.e., hostility towards women, negative attitudes regarding women, sexual dominance, impersonal sex) and a behavioral indicator of an impersonal sexual behavior (i.e., number of one-night stands). Survey data were collected from 470 single men living in the Detroit Metropolitan area. The importance of personality traits varied as a function of the outcome with anger most predictive of hostility toward women; erratic lifestyle most predictive of impersonal sexual attitudes and behavior, and entitlement most predictive of sexual dominance and negative attitudes toward women. These outcome-specific findings are interpreted and directions for future research are discussed.     

A longitudinal investigation of the mediating role of self-esteem and body importance in the relationship between stress and body dissatisfaction in adolescent females and males

Body dissatisfaction is particularly prevalent during adolescence and has recently been linked to stress in females and males. However, prospective studies are needed to better understand the relationship between stress and body dissatisfaction. The present study investigates the direction of this association and the mediating role of self-esteem and body image importance. A sample of 298 adolescent females and males in Grades 7 to 10 (ages 12 to 17 years) were surveyed at two time points over a one-year period. Hierarchical regression analyses revealed that stress significantly predicted body dissatisfaction one year later. Furthermore, a multiple mediation analysis controlling for gender revealed a significant indirect effect in both cross-sectional and longitudinal models, indicating that stress predicts reductions in self-esteem and increases in body importance, which in turn predict body dissatisfaction. These findings suggest that stress, self-esteem, and body importance should be included in programmes aimed at improving body dissatisfaction.     

绝对的公平和相对的公平

效率和公平是经济伦理的两大原则 ,也是制定和衡量经济政策的价值依据 ,但大部分经济学家都认为 ,效率和公平存在着不可调和的矛盾 ,使得人们在指导经济行为和制定经济政策时处于两难境地。本文通过对自由主义、平等主义和功利主义公平观的批判 ,试图说明 ,从历史唯物主义的立场出发 ,抛弃绝对的公平观 ,主张相对的公平观 ,便能够解决这个难题。     

程序公正对网络集群行为倾向的影响:群体相对剥夺和群体认同的作用*

程序公正对于建设和谐美好社会具有重要现实意义。研究采用情境实验法,编制程序公正材料,考察群体相对剥夺在程序公正影响网络集群行为倾向中的中介作用以及群体认同的调节作用。结果显示:(1)程序公正负向影响大学生的网络集群行为倾向;(2)群体相对剥夺在程序公正与网络集群行为倾向间起中介作用;(3)对于高群体认同者,低程序公正更容易通过增强群体相对剥夺进而提高其网络集群行为倾向。研究为促进公正管理实践、预防网络集群行为以建设和谐社会提供实践指导。