试论人类经济历史发展过程的波形路径

资本主义经济危机与周期的理论 ,是马克思主义政治经济学中固有的理论。对这一理论的研究 ,已逐渐延伸到对社会经济发展过程中一般周期性波动问题的探讨。人类经济的发展 ,是否也呈现一定的周期性 ?本文试图说明 ,人类经济历史发展过程 ,是沿着某种曲折的波形路径推进的     

Small‐sphere distributions for directional data with application to medical imaging

We propose novel parametric concentric multi‐unimodal small‐subsphere families of densities for p ? 1 ≥ 2‐dimensional spherical data. Their parameters describe a common axis for K small hypersubspheres, an array of K directional modes, one mode for each subsphere, and K pairs of concentrations parameters, each pair governing horizontal (within the subsphere) and vertical (orthogonal to the subsphere) concentrations. We introduce two kinds of distributions. In its one‐subsphere version, the first kind coincides with a special case of the Fisher–Bingham distribution, and the second kind is a novel adaption that models independent horizontal and vertical variations. In its multisubsphere version, the second kind allows for a correlation of horizontal variation over different subspheres. In medical imaging, the situation of p ? 1 = 2 occurs precisely in modeling the variation of a skeletally represented organ shape due to rotation, twisting, and bending. For both kinds, we provide new computationally feasible algorithms for simulation and estimation and propose several tests. To the best knowledge of the authors, our proposed models are the first to treat the variation of directional data along several concentric small hypersubspheres, concentrated near modes on each subsphere, let alone horizontal dependence. Using several simulations, we show that our methods are more powerful than a recent nonparametric method and ad hoc methods. Using data from medical imaging, we demonstrate the advantage of our method and infer on the dominating axis of rotation of the human knee joint at different walking phases.     

Noninformative priors for the between-group variance in the unbalanced one-way random effects model with heterogeneous error variances

For the unbalanced one-way random effects model with heterogeneous error variances, we propose the non-informative priors for the between-group variance and develop the first- and second-order matching priors. It turns out that the second-order matching priors do not exist and the reference prior and Jeffreys prior do not satisfy a first-order matching criterion. We also show that the first-order matching prior meets the frequentist target coverage probabilities much better than the Jeffreys prior and reference prior through simulation study, and the Bayesian credible intervals based on the matching prior and reference prior give shorter intervals than the existing confidence intervals by examples.     

Loneliness and the use of social media to follow celebrities: A moderating role of social presence

Because social media provide users with the possibility of an easy way to communicate with celebrities in society, it has become a more common practice to follow celebrities through social media. However, there exists few studies that examine how people’s individual characteristics are related to their celebrity-following behavior. In this regard, the current study examines whether celebrity followers’ loneliness is associated with the following behavior of their favorite celebrity. Data were collected through an online survey (N = 210). Primary findings suggest that celebrity followers’ loneliness is positively related to frequent visits of their favorite celebrity’s social media, greater social-interpersonal motive for following the celebrity, and greater enjoyment of learning about personal life stories of the celebrity. Social presence is found to be a significant moderator that can intensify more favorable parasocial relationship perceptions with the celebrity.     

Stakeholder perceptions of contextual factors related to PBIS implementation in high need schools

Positive behavior intervention and supports (PBIS) is a thoroughly researched three-tiered framework for preventing and treating challenging behavior in schools. While more than 20 years of research contribute to the literature base, less is known about PBIS implementation in high-needs school settings, particularly those that serve students predominantly from low-income families and majority minority student populations across urban and rural districts. This study investigated the critical contextual factors of PBIS implementation from the stakeholder perspective. Specifically, we surveyed 161 participants including teachers, school staff members, and administrators who were PBIS team members and had received technical assistance in PBIS implementation. The completed surveys were analyzed with participants and their schools coded for district type, Title I funding, and position in order to determine how the perceptions of issues such as buy-in, administrator support, PBIS in secondary school settings, and poverty affect PBIS implementation and team needs. The factor analysis and resulting structure along with statistically significant results for each factor are presented along with implications.     

Training Bodies,Building Status: Negotiating Gender and Age Differences in the U.S. Fitness Industry

What role does the body play in facilitating interaction across status differences? Whereas previous scholarly work has focused on “roles” and “specialized knowledge,” I investigate how bodies, appearances, and physical abilities are also consequential in these exchanges through the concept of “bodily capital.” Coined by Bourdieu, bodily capital provides a way to understand why individuals invest time, energy, and resources into their bodies, and what they expect to receive in return. As a concept, bodily capital is necessarily broad as it encompasses a variety of forms, including athletic prowess, attractiveness, physique, muscle tone/strength, agility, and other modes of embodiment. Because the body is integral to a variety of status distinction-making processes, individuals invest in and exchange bodily capital to increase their relative status in specific fields. Drawing on interviews with 26 personal trainers and 25 clients, as well as more than one year of participant observation, I find that trainers and clients use bodily capital to negotiate gender and age differences, either by re-arranging interactional power dynamics or resisting stereotypes. The type of bodily capital that allows for such negotiations to take place, however, is the hegemonic thin-toned ideal—a classed and largely raced form of bodily capital that has purchase in the U.S. fitness industry. Although individuals in the study were able to use this form of capital to enable successful cross-status interactions, doing so reified the dominance of middle-class, white bodily aesthetics. Thus, while bodily capital may challenge some status hierarchies, it reinforces others.     

Individuals and Communities: the Importance of Neighbors Volunteering

In this analysis, I examine the effects of community-level volunteering on an individual’s choices regarding time – whether to work and whether to volunteer. In order to better explain the decision to volunteer, a classic pure public goods structure is contrasted with a less restrictive impure public goods model that admits other possible private motivations. The results of this study undermine the neoclassical notion that volunteering can be understood solely as a pure public good that is provided less when others are seen to be contributing. In fact, individuals are found to be more, not less, likely to volunteer when others in their communities do so. An innovative instrumental variables strategy is used to account for reflection bias and the possible endogeneity caused by selective sorting of individuals into neighborhoods, which allows for a causal interpretation of these results. Employment regressions provide preliminary evidence that average volunteering relates, to some extent, with the decision of whether to participate in the labor force. Variations in the effect of average volunteering across age and gender are also explored. The present work is unique by virtue of its use of a large and representative dataset, along with rigorous statistical testing. I use United States Census 2000 Summary File 3 and Current Population Survey (CPS) 2004–2007 September Supplement file data and control for various individual and community-level characteristics.     

Apathy and Antipathy: Media Coverage of Restrictive Immigration Legislation and the Maintenance of Symbolic Boundaries

Although the government no longer explicitly establishes boundaries of whiteness, it continues to play a central role in shaping symbolic boundaries between immigrants and nonimmigrants through immigration lawmaking. However, the salience of these boundaries may depend on how the media disseminate them to the public. In this study, we investigate media framing of immigration lawmaking using an original data set of news coverage of six of the most widely recognized exclusionary immigration bills and laws at different levels of government. Two patterns emerged from an iterative frame analysis. First, in their coverage of frames critical of these bills and laws, outlets devoted more attention to the effects of exclusionary legislation for nonimmigrants. Second, in their coverage of frames supportive of the restrictive legislation, outlets provided more space to those who openly associated immigrants with criminality and terrorism. Regardless of outlets’ seemingly neutral stance toward restrictive legislation, their disparate coverage of exclusionary lawmaking demonstrates apathy and antipathy toward immigrants, which has repercussions for the maintenance of inequality.     

Winning a Battle but Losing the War? Third Sector and Social Policy in Latin America: The Case of Uruguay

This paper analyzes some aspects of the third sector’s involvement process in the provision of public social services. Using evidence garnered in previous research based on in-depth interviews, I offer elements toward an assessment of the consequences this process has produced not only in terms of the gains and losses it has produced for social policy, but also for the very identity and constitutive characteristics of the third sector. The evidence hereby compiled strengthens skepticism toward the hypothesis that sees a transformative potential in the role of the third sector in social policy in Latin America. This skepticism arises from issues detected by involved actors themselves and that are linked to the weakness of the sector as a whole.