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141.
142.
This study uses Lovejoy and Saxton's (2012) hierarchy of engagement to analyze how nonprofit human service organizations use Facebook and Twitter to engage stakeholders. Their framework has not been applied to this nonprofit subgroup, and most previous scholarship on this topic focuses on just one platform. We also contribute by drawing on organizational theory to better understand variation in the modes of engagement organizations emphasize. Based on our analysis, we add new subcategories to the hierarchy of engagement. In addition, we find that compared to other nonprofit subgroups examined in previous research, the organizations in our sample placed a greater emphasis on using social media messages to ask stakeholders to take action. We report only modest variations in how organizations were using Facebook and Twitter. Finally, according to our results, resource dependence and stewardship theories help explain the modes of engagement organizations prioritize.  相似文献   
143.
Urban Ecosystems - Generalist wildlife species often thrive in urban environments because of increased anthropogenic resources. However, human-wildlife interactions, especially if negative, raise...  相似文献   
144.
Urban Ecosystems - Critical resources for birds nesting in cities can support populations in spite of the challenges imposed by urbanization, and the identification of such resources can shed light...  相似文献   
145.
Technology is pervasive in homes of families with young children, despite evidence for negative associations between infant exposure to screen‐based media and cognitive development that has led the American Academy of Pediatrics (AAP) to discourage parents from exposing children under the age of 18 months to any kind of screen time (AAP, 2016). Here, we apply a propensity score matching approach to estimate relations between electronic screen‐based media use in infancy and executive function in early toddlerhood. In an international sample of 416 firstborn infants, parental report of regular exposure to screen‐based media at 4 months predicted poorer performance on a test of inhibition at 14 months, but was unrelated to either cognitive flexibility or working memory at 14 months. Results of this study are therefore consistent with the view that early exposure to screen‐based media adversely affects the development of executive function.  相似文献   
146.
Population Research and Policy Review - The issue of population ageing is no longer exclusively centred on developed countries. Empirical studies have proven that the rise in the proportion of the...  相似文献   
147.
Practitioners and researchers have long been interested in achieving the highest response rate within resource constraints on their mailed surveys. Achieving this high response rate typically has required the selection of the right mix of response-facilitating techniques. The selection decisions were generally made under the assumption that the response-facilitating techniques act independently of one another. The authors have examined the validity of this independence assumption by identifying the major response facilitators in use and then analyzing the results of 531 independent mail survey studies. The authors conclude that major facilitators do not function independently. In fact, it was found that significant joint action interactive effects on response rates do exist. Practitioners and researchers who are faced with the survey design decisions of choosing response facilitators can receive assistance by reviewing the results of this diverse collection of reported experiences.  相似文献   
148.
The paper examines to what extent a player's market value depends on his skills. Therefore, a data set covering 28 performance measures and the market values of about 493 players from 1. and 2. German Bundesliga is analysed. Applying robust analysis techniques, we are able to robustly estimate market values of soccer players. The results show (1) that there are significantly underrated and overrated players and (2) that a player's affiliation to a certain team may contribute to his market value. We conclude that a club's reputation affects the market values of its players and that star players are in tendency overrated.  相似文献   
149.
In this paper, we discuss the usual stochastic and reversed hazard rate orders between the series and parallel systems from two sets of independent heterogeneous exponentiated Weibull components. We also obtain the results concerning the convex transform orders between parallel systems and obtain necessary and sufficient conditions under which the dispersive and usual stochastic orders, and the right spread and increasing convex orders between the lifetimes of the two systems are equivalent. Finally, in the multiple-outlier exponentiated Weibull models, based on weak majorization and p-larger orders between the vectors of scale and shape parameters, some characterization results for comparing the lifetimes of parallel and series systems are also established, respectively. The results of this paper can be used in practical situations to find various bounds for the important aging characteristics of these systems.  相似文献   
150.
The main objective of this work is to evaluate the performance of confidence intervals, built using the deviance statistic, for the hyperparameters of state space models. The first procedure is a marginal approximation to confidence regions, based on the likelihood test, and the second one is based on the signed root deviance profile. Those methods are computationally efficient and are not affected by problems such as intervals with limits outside the parameter space, which can be the case when the focus is on the variances of the errors. The procedures are compared to the usual approaches existing in the literature, which includes the method based on the asymptotic distribution of the maximum likelihood estimator, as well as bootstrap confidence intervals. The comparison is performed via a Monte Carlo study, in order to establish empirically the advantages and disadvantages of each method. The results show that the methods based on the deviance statistic possess a better coverage rate than the asymptotic and bootstrap procedures.  相似文献   
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