Discretionary Time of Chinese College Students: Activities and Impact of SARS-Induced Constraints on Choices

How people make choices about activity engagement during discretionary time is a topic of increasing interest to those studying quality of life issues. Assuming choices are made to maximize individual welfare, several factors are believed to influence these choices. Constraints theory from the leisure research literature suggests these choices are heavily influenced by intrapersonal, interpersonal and structural constraints. Within these constraints, the individual is motivated to make choices that maximize perceived personal welfare. Leisure affordance theory focuses on these motivations by suggesting the importance of more positive influences on choices within a set of constraints. In this study, an inventory of discretionary time activities and reasons for choosing these activities were documented for a sample of Chinese college students. Because data were collected during an unanticipated SARS epidemic, the impact of the SARS crisis on students’ daily choices was also examined in detail. Despite the constraints imposed by SARS and the attendant suspension of off-campus activities, some students did not perceive a change of daily life as a result, while others perceived positive changes in attitudes and behavior. Findings shed light on students’ experiences during a time of rapid change in Chinese society and higher education. Decisions made during this influential time of life are important because they may affect students’ future choices related to leisure and discretionary time.     

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This paper treats some of the special and unfamiliar problems encountered in presenting in a courtroom setting the result of a sample survey which leads to reporting an estimate. It develops that the minor problem of non-response in surveys is very much aggravated in legal evidentiary evaluation, leading to the necessity of exercising much more stringent follow-up procedures. It is claimed that the interval estimate form is almost ideally suited to presentation before a judge, jury, and legal counsel.     

粪肥纤维单胞菌木质素 11A基因野生型与点突变子底物结合特性研究(英文)

本文报道 ,应用点突变技术获得的粪肥纤维单胞菌 (Cellulomonasfimi)木质素酶 11A(Xyn11A)基因的3个点突变子 ,即R2 62G ,R573G和R2 62G R573G ,表达产物结合底物特性的测定结果。试验表明 ,R2 62G R573GXyn11A与野生型Xyn11A基因表达产物结合底物的特性明显不同 ,表现为前者不与木质素结合而与纤维素结合 ,后者与纤维素和木质素均结合 ,但与木质素结合能力更强 ,与野生型Xyn11A一样 ,R2 62GXYN11A和R573GXyn11A也能与纤维素和木质素两者结合 ,但与纤维素的结合力更强 ,而与木质素结合力弱。用纤维素作为底物测定Xyn11A和R2 62G ,R573G和R2 62G R573GXyn11A的Kr值分别为 0 .6,1.1,1.1和 1.9L g。     

The economic costs of childhood poverty in the United States

This paper attempts to estimate the aggregate annual costs of child poverty to the US economy. It begins with a review of rigorous research studies that estimate the statistical association between children growing up in poverty and their earnings, propensity to commit crime, and quality of health later in life. We also review estimates of the costs that crime and poor health impose on the economy. Then we aggregate all of these average costs per poor child across the total number of children growing up in poverty in the United States to obtain our estimate of the aggregate costs of the conditions associated with childhood poverty to the US economy. Our results suggest that these costs total about $500 billion per year, or the equivalent of nearly 4% of gross domestic product (GDP). More specifically, we estimate that childhood poverty each year: (1) reduces productivity and economic output by an amount equal to 1.3% of GDP, (2) raises the costs of crime by 1.3% of GDP, and (3) raises health expenditures and reduces the value of health by 1.2% of GDP.     

From Global Knowledge Management to Internal Electronic Fences: Contradictory Outcomes of Intranet Development

This paper considers the adoption of intranet technology as a vehicle for encouraging organization-wide knowledge sharing within a large, global bank. Ironically, the outcome of intranet adoption was that, rather than integrate individuals across this particular organization, the intranet actually helped to reinforce the existing functional and national boundaries with 'electronic fences'. This could be partly explained by the historical emphasis on decentralization within the bank, which shaped and limited the use of the intranet as a centralizing, organization-wide tool. This is possible because the intranet can be described as an interactive and decentred technology, which therefore has the potential for multiple interpretations and effects. Thus, while the intranet is often promoted as a technology that enables processes of communication, collaboration and social coordination it also has the potential to disable such processes. Moreover, it is argued that to develop an intranet for knowledge-sharing requires a focus on three distinctive facets of development. These different facets may require very different, sometimes contradictory, sets of strategies for blending the technology and the organization, thus making it extremely difficult for a project team to work effectively on all three facets simultaneously. This was evidenced by the fact that none of the independent intranet-implementation projects considered actually managed to encourage knowledge-sharing as intended, even within the relatively homogeneous group for which it was designed. Broader knowledge-sharing across the wider organizational context simply did not occur even among those who were working on what were defined as 'knowledge management' projects. A paradox is that knowledge-sharing via intranet technologies may be most difficult to achieve in contexts where knowledge management is the key objective.     

Women's sexual working models: an evolutionary-attachment perspective

In three studies, we developed and validated a self-report measure of women's sexual working models. In a pilot study we created an initial version of the Women's Sexual Working Models Scale (WSWMS), administered it to an exploratory sample of 470 women, and identified its 5-factor structure. Study 1 confirmed the 5-factor structure in a new sample: (1) Fostering commitment; (2) Evaluating a sexual partner's suitability; (3) Promoting frequent sexual activity through positive affect; (4) Restricting sexuality through shamefulness; and (5) Negative emotions that signal incompatibility with relationship goals. In Study 2, 444 Israeli women completed the WSWMS. Confirmatory factor analysis provided cross-national evidence for the generalizability of the underlying factor structure of the WSWMS.     

Negative binomial time series models based on expectation thinning operators

The study of count data time series has been active in the past decade, mainly in theory and model construction. There are different ways to construct time series models with a geometric autocorrelation function, and a given univariate margin such as negative binomial. In this paper, we investigate negative binomial time series models based on the binomial thinning and two other expectation thinning operators, and show how they differ in conditional variance or heteroscedasticity. Since the model construction is in terms of probability generating functions, typically, the relevant conditional probability mass functions do not have explicit forms. In order to do simulations, likelihood inference, graphical diagnostics and prediction, we use a numerical method for inversion of characteristic functions. We illustrate the numerical methods and compare the various negative binomial time series models for a real data example.     

Tail Behavior of the Failure Rate Functions of Mixtures

The tail behavior of the failure rate of mixtures of lifetime distributions is studied. A typical result is that if the failure rate of the strongest component of the mixture decreases to a limit, then the failure rate of the mixture decreases to the same limit. For a class of distributions containing the gamma distributions this result can be improved in the sense that the behavior of the failure rate of the mixture asymptotically mirrors that of the strongest component in whether it decreases or increases to a limit. This revised version was published online in July 2006 with corrections to the Cover Date.