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1.
A central problem in compressed sensing is the construction of sensing matrices. In this paper, we show how to construct sensing matrices by using semilattices, and give many examples of sensing matrices constructed from specific semilattices. Moreover, we show that the new construction for some examples with small parameters gives better sensing matrices compared with previously known constructions. 相似文献
2.
Let X = {X1, X2, …} be a sequence of independent but not necessarily identically distributed random variables, and let η be a counting random variable independent of X. Consider randomly stopped sum Sη = ∑ηk = 1Xk and random maximum S(η) ? max?{S0, …, Sη}. Assuming that each Xk belongs to the class of consistently varying distributions, on the basis of the well-known precise large deviation principles, we prove that the distributions of Sη and S(η) belong to the same class under some mild conditions. Our approach is new and the obtained results are further studies of Kizinevi?, Sprindys, and ?iaulys (2016) and Andrulyt?, Manstavi?ius, and ?iaulys (2017). 相似文献
3.
Seokho Hong 《Asian Social Work and Policy Review》2019,13(1):46-57
Studies have mostly examined mental health service use of older Asian immigrant combining all Asian Americans into one group whereas immigration backgrounds and socioeconomic status of each Asian minority group are different. Therefore, this study aimed to identify predictors of mental health service use within specific ethnic groups among older Asian adults focusing on Chinese, Japanese, Korean, Filipino, and Vietnamese in California. The Behavioral Model for Vulnerable Populations (BMVP) is used to guide the secondary data analysis of a sample of 3,453 older Asian immigrants from the California Health Interview Survey (CHIS). Logistic and linear regression analyses are performed to examine predictors of mental health service use and the frequency of mental health service use, respectively. As results, mental health‐seeking patterns differ by ethnicity within the older Asian immigrant sample, not being married (Korean), higher levels of acculturation (Filipino), lower levels of neighborhood cohesion (Korean and Vietnamese), higher levels of perceived safety (Korean) and lower levels of perceived safety (Vietnamese), higher levels of mental distress (Korean and Filipino), and having perceived need (all) were related to more visits for mental health services. The study findings highlight the necessity of cultural competency services and programs for each Asian ethnicity. 相似文献
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The widely used empirical Bayes (EB) and full Bayes (FB) methods for before–after safety assessment are sometimes limited because of the extensive data needs from additional reference sites. To address this issue, this study proposes a novel before–after safety evaluation methodology based on survival analysis and longitudinal data as an alternative to the EB/FB method. A Bayesian survival analysis (SARE) model with a random effect term to address the unobserved heterogeneity across sites is developed. The proposed survival analysis method is validated through a simulation study before its application. Subsequently, the SARE model is developed in a case study to evaluate the safety effectiveness of a recent red‐light‐running photo enforcement program in New Jersey. As demonstrated in the simulation and the case study, the survival analysis can provide valid estimates using only data from treated sites, and thus its results will not be affected by the selection of defective or insufficient reference sites. In addition, the proposed approach can take into account the censored data generated due to the transition from the before period to the after period, which has not been previously explored in the literature. Using individual crashes as units of analysis, survival analysis can incorporate longitudinal covariates such as the traffic volume and weather variation, and thus can explicitly account for the potential temporal heterogeneity. 相似文献
6.
In end‐of‐life (EOL) care research, death anxiety and religiosity are often overlooked. Terror management theory (TMT) may provide a useful conceptual model with which to examine how comfort discussing death and religiosity influence attitudes related to EOL care. A telephone‐based survey was conducted among community‐dwelling adults in the Unites States. Via random sampling, with over‐sampling of Hispanics/African Americans, 123 completed survey interviews (response rate = 46%) were analyzed. Respondents were more likely to have better attitudes toward EOL care if they were older or white, religiously active, and comfortable with the subject of death. Religiosity and comfort discussing death were correlated with each other and remained significant predictors of attitudes about EOL care even without demographic covariates. Findings suggest that promoting an open dialogue about mortality may improve attitudes about EOL care and utilization of palliative care services. The study also provides evidence about the utility and applicability of TMT for EOL care. 相似文献
7.
This paper considers the tail asymptotic of discounted aggregate claims with compound dependence under risky investment. The price of risky investment is modeled by a geometric Lévy process, while claims are modeled by a one-sided linear process whose innovations further obeying a so-called upper tail asymptotic independence. When the innovations are heavy tailed, we derive some uniform asymptotic formulas. The results show that the linear dependence has significant impact on the tail asymptotic of discounted aggregate claims but the upper tail asymptotic independence is negligible. 相似文献
8.
The aim of this paper is to examine whether and how rural residents’ educational attainment is associated with their self-rated health in China. Taking advantage of the National Exercise Facility Survey that was collected between December 2015 and March 2016, we find that educational attainment has a significant and positive correlation with self-rated health, net of the effects of age, gender, and geographical region. This correlation is mediated by factors such as perceived importance of exercise and healthy lifestyle. Relatively, people’s cognitive knowledge about health-related information and material resource access fail to play a significant mediating role. The findings highlight the non-material and non-cognitive attributes of educational attainment in shaping the gradient of health in the rural setting of China. Interventions that expand formal education to the mass and optimize teaching contents may offer an effective means to balance the health gradient. 相似文献
9.
传统的国际化理论模型长期用一种刻板、静态的思想对国际化活动进行思考,事实上,企业的国际化成长过程存在着复杂的、多元的国际化行为组合和行为序列模式。即使在国际化程度相同的情况下,国际化过程的差异也可能导致截然不同的组织绩效。中国企业国际化过程体现出的“加速”和“跳跃”特征令世界瞩目,但少有研究关注中国企业国际化过程背后的管理者决策逻辑。而且,目前相关研究大多基于管理者理性人假设,忽略了管理者非理性行为对国际化过程特征的影响。
基于高阶梯队和行为金融等理论,探讨高管过度自信对中国企业对外直接投资速度和节奏等国际化动态过程特征的影响,并考察在内部股权结构和外部国际化压力的双重情景下该影响机制的变化情况。以具有国际化行为的中国上市公司为研究样本,通过手工整理获取2007年至2013年301家上市公司国际化过程面板数据,选择固定效应模型进行多元回归分析。
研究结果表明,①高管过度自信与国际化速度和国际化节奏之间均存在显著的正相关关系,即高管过度自信心理会促使中国企业国际化过程的速度增加,不规律性增强;②内部国有股权比例增加显著增强高管过度自信对国际化速度和国际化节奏的正向影响;③企业外部产业国际化竞争压力显著遏制中国企业高管过度自信对企业国际化速度和国际化节奏的正向影响。
在中国特定的制度环境和管理情景下,讨论高管过度自信心理对企业国际化过程特征产生的影响,验证了中国企业国际化扩张背后存在的高管非理性因素,为行为金融理论和国际化过程研究等相关研究领域的进一步推进做出了贡献。另外,探讨内部股权和外部产业竞争的影响,进一步丰富了公司治理和产业竞争的相关实证研究。研究结论对于高管团队管理和企业国际化决策管理具有较好的实践指导意义。 相似文献
10.