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141.
Understanding how people view flash flood risks can help improve risk communication, ultimately improving outcomes. This article analyzes data from 26 mental models interviews about flash floods with members of the public in Boulder, Colorado, to understand their perspectives on flash flood risks and mitigation. The analysis includes a comparison between public and professional perspectives by referencing a companion mental models study of Boulder‐area professionals. A mental models approach can help to diagnose what people already know about flash flood risks and responses, as well as any critical gaps in their knowledge that might be addressed through improved risk communication. A few public interviewees mentioned most of the key concepts discussed by professionals as important for flash flood warning decision making. However, most interviewees exhibited some incomplete understandings and misconceptions about aspects of flash flood development and exposure, effects, or mitigation that may lead to ineffective warning decisions when a flash flood threatens. These include important misunderstandings about the rapid evolution of flash floods, the speed of water in flash floods, the locations and times that pose the greatest flash flood risk in Boulder, the value of situational awareness and environmental cues, and the most appropriate responses when a flash flood threatens. The findings point to recommendations for ways to improve risk communication, over the long term and when an event threatens, to help people quickly recognize and understand threats, obtain needed information, and make informed decisions in complex, rapidly evolving extreme weather events such as flash floods.  相似文献   
142.
Doubly truncated survival data arise when event times are observed only if they occur within subject specific intervals of times. Existing iterative estimation procedures for doubly truncated data are computationally intensive (Turnbull 38:290–295, 1976; Efron and Petrosian 94:824–825, 1999; Shen 62:835–853, 2010a). These procedures assume that the event time is independent of the truncation times, in the sample space that conforms to their requisite ordering. This type of independence is referred to as quasi-independence. In this paper we identify and consider two special cases of quasi-independence: complete quasi-independence and complete truncation dependence. For the case of complete quasi-independence, we derive the nonparametric maximum likelihood estimator in closed-form. For the case of complete truncation dependence, we derive a closed-form nonparametric estimator that requires some external information, and a semi-parametric maximum likelihood estimator that achieves improved efficiency relative to the standard nonparametric maximum likelihood estimator, in the absence of external information. We demonstrate the consistency and potentially improved efficiency of the estimators in simulation studies, and illustrate their use in application to studies of AIDS incubation and Parkinson’s disease age of onset.  相似文献   
143.
Using data from the 2003?C2007 American Time Use Surveys (ATUS), we compare mothers?? (N = 6,640) time spent in four parenting activities across maternal education and child age subgroups. We test the hypothesis that highly educated mothers not only spend more time in active child care than less-educated mothers but also alter the composition of that time to suit children??s developmental needs more than less-educated mothers. Results support this hypothesis: not only do highly educated mothers invest more time in basic care and play when youngest children are infants or toddlers than when children are older, but differences across education groups in basic care and play time are largest among mothers with infants or toddlers; by contrast, highly educated mothers invest more time in management activities when children are 6 to 13?years old than when children are younger, and differences across education groups in management are largest among mothers with school-aged children. These patterns indicate that the education gradient in mothers?? time with children is characterized by a ??developmental gradient.??  相似文献   
144.
145.
There is a growing social work literature about lesbian, gay, bisexual, and transgender (LGBT) older people. However, research and guidance are predominantly based on the experiences of older gay men and, to a lesser extent, older lesbians. There is little to help practitioners work with older bisexual people. The Looking Both Ways study aimed to contribute to this gap in knowledge. We undertook in-depth purposely sampled qualitative interviews with 12 people aged over 50, all of whom have bisexual relationship histories and half of whom also currently identify as bisexual. There were three main findings. First, biphobia (prejudice against bisexual people) impacts on older people with bisexual histories in ways that may affect their well-being in later life. Second, concerns around receiving care are similar in some ways and different in others from the concerns of lesbians and gay men. Third, people with bisexual relationship histories may have developed strong support networks and resilience, factors that may be very beneficial in later life. Three recommendations for social work professionals were identified: 1) understand biphobia, 2) recognize the legitimacy of concerns about receiving care, and 3) ask about support networks rather than assuming family support.  相似文献   
146.
Although research with hard‐to‐reach populations is necessary to deepen the social work knowledge base and improve services to these groups, recruiting members of hard‐to‐reach populations for research projects is often a challenging process. Frequently, non‐probability sampling is used to obtain participants. However, the difficulties and limitations associated with this process in quantitative research are rarely discussed in depth in the literature. Sampling issues can significantly impact a research project, delaying it, extending it or even causing the premature termination of a project. Challenges to recruitment can limit the type of research that is completed, impact the knowledge base or introduce threats to validity through sampling bias. Using a preliminary quantitative study on parental engagement with child protective services as an illustration for the discussion, the challenges of non‐probability sampling with a hard‐to‐reach population and the implications for research practice are explored and discussed. Implications for future research practice are considered.  相似文献   
147.
Abstract

The authors surveyed 738 college students aged 18 to 27 years to assess overweight, obesity, dietary habits, and physical activity. They used BMI (body mass index) > 25 kg/m2 or BMI > 85th percentile and BMI > 30 kg/m1 or BMI > 95th percentile to estimate overweight and obesity in those aged < 19 years. To define overweight and obesity in those > 20 years, they used BMI > 25 kg/m2 and > 30 kg/m2. They found overweight rates of 21.6% using BMI directly and 16.2% using BMI percentile and obesity rates of 4.9% using BMI directly and 4.2% using BMI percentile. More than 69% of the participants reported < 5 servings of fruits and vegetables per day and more than 67% reported < 20 g of fiber per day; participants reported physical activity on fewer than 3 d/wk. Most college students are not meeting dietary and physical activity guidelines, suggesting the need for prevention interventions and increased understanding of overweight in college students.  相似文献   
148.
External ratings of organizations have proliferated in the last few decades, impacting not only the behavior of consumers but also of the organizations being rated. This phenomenon has been widely studied in regards to the U.S. News and World Reports ratings of universities and law schools. This article strives to understand how third party ratings impact the behavior of nonprofits using the financial data the nonprofits provide in their IRS Forms 990. The results show that such ratings are, in fact, having an effect on how nonprofits report financial information on the IRS Form 990.  相似文献   
149.
Technology and Education for Career Heights (Project TECH) was designed to help Temporary Assistance to Needy Families participants enhance their literacy through distance learning as a means to promote job retention and career advancement. The evaluative research presented in this report was intended to gather information from the participants of Project TECH about their experience with distance learning training curriculum. The report describes Project TECH and what happens when participants who are low-income workers are given a computer, basic training software, Internet access, and training coupled with instruction form a instructor who met with them face to face weekly and provided daily online coaching and instruction. It highlights participants' experience with online instruction and the use of computers in their homes, and it concludes with lessons learned from the project. The information is useful for those wanting to design and develop a distance learning program to increase adult literacy for families that needs to comply with Temporary Assistance to Needy Families work requirements and other demands.  相似文献   
150.
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