唤醒心中的天使

解放军战士雷锋是伟大的楷模。雷锋省吃俭用,生活朴素,穿着打补丁的袜子,人家喝汽水的时候他喝白开水,一分一分积攒下来的钱默默无闻地捐给灾区。在去医院看病的路上看到工地缺少搬砖人手,他竟忘却了自己带病的身体还和别人展开了搬砖比赛。吃苦在前、一生都为别人服务的他仅仅20多岁就离开了人世,但他的事迹传遍了整个中国,毛泽东主席还题辞"向雷锋同志学习",全中国掀起了学习雷锋的热潮。雷锋唤醒了我心中的天使!无论是中国人还是韩国人,全世界人类心中都有"天使",重要的是你是     

A dynamic multistate model of robustness and frailty

Dynamic multistate models can show realistic population dynamics over time, model complex cycles, and encompass the life history of a cohort. This paper uses a recently developed approach to obtain the analytic solution of a time‐dependent multidimensional differential equation. The illustrative robust/frail model presented shows that the assumption of fixed individual frailty can be abandoned in a two living state model that allows transitions between health statuses and nonproportional hazards of death.     

Online Donation Experiences,Donation Awareness,and Intention of Future Donation Among Teenagers in South Korea

Younger generations have become less likely to donate than older generations. Online fundraising might be a solution to encourage young donors. This study examines the mediating effects of online donation on the donation awareness of teenagers, as well as the pathway from online donation to an intention to donate in the future. Using data collected from 287 teenagers through an online survey, the study found that online donation experience has positive effects on the frequency of future donation, mediated by donation awareness. These results suggest that nonprofit organizations should consider online donation platforms to be important fundraising mechanisms in encouraging young donors. Future research is need in order to develop the theoretical models of online donation as well as investigate the applicability of the models, especially for young generations.     

Independence distribution preserving joint covariance structures for the multivariate two-group case

We characterize the general nonnegative-definite and positive-definite joint observation covariance structures for the two-group case such that the two sample mean vectors are independent of the two corresponding sample covariance matrices. Also, the sample covariance matrices are distributed as independent noncentral or central Wishart random matrices. We derive and utilize a representation of the general common non-negative-definite solution to a particular system of matrix equations with idempotent coefficient matrices.     

Probability inequalities for continuous unimodal random variables with finite support

A paramecer-free Bernstein-type upper bound is derived for the probability that the sum S of n i.i.d, unimodal random variables with finite support, X₁ ,X₂,…,X_n, exceeds its mean E(S) by the positive value nt. The bound for P{S - nμ ≥ nt} depends on the range of the summands, the sample size n, the positive number t, and the type of unimodality assumed for X_i. A two-sided Gauss-type probability inequality for sums of strongly unimodal random variables is also given. The new bounds are contrasted to Hoeffding's inequality for bounded random variables and to the Bienayme-Chebyshev inequality. Finally, the new inequalities are applied to a classic probability inequality example first published by Savage (1961).     

Bayesian inference for comparing two Poisson rates using data subject to underreporting and validation data

We derive a new Bayesian credible interval estimator for comparing two Poisson rates when counts are underreported and an additional validation data set is available. We provide a closed-form posterior density for the difference between the two rates that yields insightful information on which prior parameters influence the posterior the most. We also apply the new interval estimator to a real-data example, investigate the performance of the credible interval, and examine the impact of informative priors on the rate difference posterior via Monte Carlo simulations.     

Who Plays What? Participation Profiles in Chance Versus Skill-based Gambling

To determine whether gambling participation falls into skill and chance-based categories and, if so, to determine the socio-demographic characteristics associated with these different categories. A cross-sectional analysis of all respondents to the 2005 Northern Territory Gambling Prevalence Survey who gambled in the 12 months prior to the survey. Factor analysis was employed to determine whether a chance versus skill-based dichotomy described the structure of gambling participation. Gambler preference groups were constructed using the median of rotated factor scores. Multinomial logit regression was then used to determine independent associations between explanatory variables and categories of gambler preferences. The skill and chance-based dichotomy did describe player preferences for the sample of adult gamblers in the Northern Territory, Australia. Gender, age, household income, household structure and the geographic location (access to gambling opportunities) of respondents were all associated with different degrees of participation in skill and chance based gambling activities. Notably, respondents 35 years and over were significantly over-represented in the low-skill/high-chance participation group, and under-represented in the high-skill/low-chance group. It is clear that the term gambling is a confounding rubric that hides differences both in the type of activity and the socio-demographic profiles of participants. An examination of the latter raises important questions about the role of chance in later life, as well as the role of self-determination in gambling for other groups, particularly younger men.     

The power of the exponential scores test for an ordinary renewal process against trend alternatives

The power properties of a statistic based on the use of exponential scores which may be used for testing whether a series of events occurring in time form an ordinary renewal process against trend alternatives are examined. Small sample power comparisons under a Lehmann trend alternative are made with an alternative nonparametric test based on a rank trend statistic and with the parametric test when the intervals are exponentially distributed. Finally, some asymptotic efficiency results are developed for limiting trend alternatives.     

Social Capital,Labour Markets,and Job‐Finding in Urban and Rural Regions: comparing paths to employment in prosperous cities and stressed rural communities in Canada1,2

This paper compares paths to employment (job‐finding) in prosperous cities and economically‐stressed rural communities in Canada. Since the pioneering work of Mark Granovetter (1973; 1974 ), sociologists have investigated the role of social capital in job‐finding (specifically, the use of strong and weak social ties to find out about employment opportunities). To date, however, there have been few direct comparisons of job‐finding in urban and rural settings (see Lindsay et al., 2005 ; Wahba and Zenou, 2005 ). Using data from two major surveys and a qualitative interview project, we uncover several important differences in urban and rural paths to employment. First, we find that both strong and weak ties are used more frequently by rural residents to find a job, while city‐dwellers rely more often on formal or impersonal means. Second, we find much stronger evidence of differentiation within rural regions. Long‐time rural residents are much more likely to use strong and weak ties to find employment than are newcomers. However, rural residents who used weak ties as paths to employment have significantly lower incomes. None of these patterns are evident in the cities. Together, these findings lead us to conclude that job‐finding in rural settings is strongly affected by constraints – in the labour market and in social capital resources – that are not present in cities.