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941.
A family of robust estimators for coefficients of Gaussian AR(p) time series under simultaneously influencing distortions of two types: outliers and missing values, is proposed. The estimators are based on special properties of the Cauchy probability distribution; consistency and the asymptotic normality of these estimators are proven. An approximate solution of the problem of minimization of the asymptotic variance within the proposed family of estimators is found. Performance of the proposed estimators is illustrated for simulated time series and for real data sets.  相似文献   
942.
Parametric confidence intervals are given for linear combinations of the means of independent Poisson variables and for their continuous versions. The performance of the intervals is assessed using simulation. A real data set is used to compare the proposed intervals with known ones. The proposed intervals are shown to be superior to known ones and comparable to exact intervals.  相似文献   
943.
New forms of youth social and political participation have been termed ‘Slacktivism’ – low-cost online forms of social engagement that decrease subsequent offline participation. Previous experimental work has provided support for a ‘Slacktivism effect,’ but it is unclear if this theoretical model applies to youth media sharing on social networking sites. This study uses a novel sharing simulation paradigm to test the effect of publicly vs. anonymously sharing a social cause video on subsequent willingness to engage in offline helping behavior. Results show that publicly (as compared to anonymously) sharing a selected video on one’s own Facebook wall led to a greater willingness to volunteer for an issue-related cause. Participants’ existing use of social media for engagement in social issues/causes moderated the effect, such that only participants low in use of social media for social engagement were susceptible to the sharing manipulation. Implications for reconceptualizing media sharing as a unique form of online participation beyond ‘Slacktivism’ are discussed.  相似文献   
944.
The current study attempts to identify the prevalence rate of and risk factors associated with elder mistreatment in Singapore, a multi-ethnic nation in South-East Asia. Information on elder mistreatment was collected from 400 non-randomly selected cognitively intact older adults in a residential area of Singapore. Items on mistreatment were adopted from the Hwalek-Sengstock Elder Abuse Screening Test and the Vulnerability to Abuse Screening Scale. Standardized scales on activities of daily living, loneliness, and items on violence between family members were administered. The prevalence rate of mistreatment was 8.3%. A family environment characterized by psychological and physical abuse between family members and a social environment characterized by loneliness increased the vulnerability of older adults to mistreatment. Older adults who were mistreated reported more depression symptoms than those who were not.  相似文献   
945.
Nowadays, the majority of human beings live in urban ecosystems, with this proportion expected to continue increasing in the future. With the growing importance of urban rat-associated issues (e.g. damages to urban infrastructures, costs of rat-control programs, rat-associated health risks), it is becoming indispensable to fill the identified gaps in knowledge on the urban brown rat regarding, among others, its density, home range, genetic structure, and infectious status. In this context, live-trapping is a crucial prerequisite to any scientific investigation. This paper assesses the main constraints and challenges regarding the urban field and describes the major steps to be considered when planning research on urban rats. The primary challenges are i) the characterization of the urban experimental unit; ii) the choice of a trapping design: the use of live-trapping in capture-mark-recapture design, in association with modern statistics, is highly recommended to answer ecological questions (although these methods, mostly developed in natural ecosystems, need to be implemented for the urban field); iii) the potential ethical considerations with regard to animal welfare and field-worker safety; iv) the building of mutually-beneficial collaborations with city stakeholders, pest control professionals, and citizens. Emphasis must be put on communication to the public and education of field-workers. One major need of modern urban rat research is a peer-validated field methodology allowing reproducibility, repeatability, and inference from urban field studies and enabling researchers to answer long-standing key questions about urban rat ecology.  相似文献   
946.
947.
948.
We consider the square contingency tables which arise when the same method of classification is applied twice. The hypothesis of marginal homogeneity is then relevant! and can be tested by various methods Models are discussed which contain marginal homogeneity as a special case. They include a class based on univariate and bivariate Dirichlet distributions. The question of ordered categories is briefly discussed. Applications are made to data on unaided distance vision.  相似文献   
949.
Memory based on a one‐time experience is an important element of its definition as “episodic.” Infants' memories for one‐time experiences over long delays are largely unexplored. Using elicited imitation, we tested 20‐ and 16‐month‐olds' (Experiment 1) and 13‐month‐olds' (Experiment 2) memories as a function of number of experiences and delay. Over 1 month, 20‐ and 16‐month‐olds remembered individual actions of one‐time events; 20‐month‐olds also remembered temporal order; with verbal reminders, 16‐month‐olds did as well. Over 3 months, recall depended on multiple experiences. Thirteen‐month‐olds' required multiple experiences, even over 1 month. The findings speak to the gradual emergence of an important element of episodic memory, namely the ability to preserve memories of one‐time experiences over long periods of time.  相似文献   
950.
This study describes the implementation of three evidence-based treatments addressing traumatic stress symptoms within a wraparound foster care program in Illinois. Child–Parent Psychotherapy (CPP), Trauma-Focused Cognitive Behavioral Therapy (TF-CBT), and Structured Psychotherapy for Adolescents Responding to Chronic Stress (SPARCS) were implemented with a racially diverse sample of youth ages 3–18 at six agencies. Culturally sensitive adaptations were made to treatment approaches to improve client retention and outcomes. Data analyses revealed no racial differences in retention in the program and no differences in outcomes between minority youth exposed to the intervention and other participants. All three evidence-based treatments were effective in reducing symptoms and improving functioning among minority youth. Implementation issues, including challenges and culturally competent accommodations, are discussed.  相似文献   
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