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821.
Les transferts de fonds et leur effet sur les indicateurs du marché du travail: illustration par le cas mexicain 下载免费PDF全文
L'effet des envois de fonds sur les indicateurs du marché du travail est abondamment traité dans la littérature, à partir de microdonnées en général. Les macrodonnées, plus rarement utilisées, posent un problème d'endogénéité lié aux corrélations possibles de la variable relative aux transferts. Dans cette analyse, fondée sur des données de panel relatives au Mexique, les auteurs cherchent à contourner le problème en utilisant un estimateur GMM en système. Ils montrent que les envois de fonds élèvent les taux d'activité tout en réduisant le nombre des heures travaillées, la fréquence de l'emploi «critique» (c'est‐à‐dire de mauvaise qualité) et la durée des épisodes de chômage. 相似文献
822.
Timothy F. Platts-Mills Joseph A. Dayaa Bryce B. Reeve Kayla Krajick Laura Mosqueda Jason S. Haukoos 《Journal of elder abuse & neglect》2018,30(4):247-270
Emergency departments (EDs) are an important health care setting for the identification of elder abuse (EA). Our objective was to develop an ED-based tool to identify EA. The initial tool included a brief cognitive assessment, questions to detect multiple domains of EA, and a physical examination. Refinement of the tool was based on input from clinical experts and nurse and patient feedback. The revised tool, which included 15 questions about EA, was then tested in an academic ED. We calculated the inter-rater reliability, sensitivity, and specificity of individual EA questions. Among ED patients age≥65 (N = 259), 17 (7%) screened positive for suspicion of EA. We identified a combination of six questions that cover the included domains of EA, demonstrated good or excellent inter-rater reliability, and had a sensitivity and specificity of 94% (95% confidence interval (CI) 71–100%) and 90% (95% CI 85–93%), respectively. These results inform a proposed screening tool for multisite validation testing. 相似文献
823.
Kathleen S. Caffrey Bruce R. Wright Patricia L. Maarhuis 《Journal of American college health : J of ACH》2018,66(3):194-201
Objective: To examine the psychometric properties of a measure of cannabis-specific Protective Behavioral Strategies (PBS), which assesses ways in which students may reduce cannabis-related risk. Participants: Respondents to the American College Health Association – National College Health Assessment II (N = 580) during Spring 2015. Methods: Exploratory Factor Analysis (EFA) and Exploratory Structural Equation Modeling (ESEM) were used to identify and replicate the factor structure of the measure. Results: Results support a four-factor model (Respiratory Health, Frequency/Quantity, Socializing, and General Health) with close approximate fit (Χ2 (310) = 565.96, p < .001, RMSEA = .038 (.033, .043; 90% CI), CFI = .961, TLI = .929, SRMR = .033). Support for the convergent validity and construct validity of the measure was also found. Conclusions: This is the initial step in the development of a standard, psychometrically validated measure of cannabis PBS that has the potential to inform future research and interventions. 相似文献
824.
Objective: This study examined symptoms of anxiety and depression among college students with attention-deficit/hyperactivity disorder (ADHD). Participants: Data were collected between March 2011 and March 2016 from 150 college students with ADHD and 150 college students without ADHD. Method: Participants with ADHD were compared to a sex- and ethnicity-matched control group. For the ADHD group, parent and self-report of anxiety and depression were also compared. Results: College students with ADHD self-reported significantly higher anxiety and depressive symptoms than did students without ADHD. Scores on parent-report measures of anxiety and depressive symptoms were significantly higher than scores on self-report measures. Significant sex differences were found for participants with ADHD, with females showing higher depressive and anxiety symptoms than males. Parent-reported anxiety symptoms were higher for those with inattentive type ADHD compared to combined type ADHD. Conclusion: The current study highlights the importance of multi-informant assessment in ADHD evaluations for college-aged adults. 相似文献
825.
Laura J. Heideman 《Voluntas: International Journal of Voluntary and Nonprofit Organizations》2018,29(2):333-347
What makes civil society sustainable? This paper examines USAID “Legacy Mechanisms”—programs designed to support a stable civil society after USAID withdraws aid—in the context of post-war Croatia to reconceptualize civil society sustainability in terms of resilience. Rather than examine whether specific legacy mechanisms remained intact, this paper looks at how Croatian civil society organizations adopted, adapted, and dropped these legacy programs to respond to novel crises and a changing political and social environment once USAID exited Croatia. Drawing on archival data from USAID’s time in Croatia and interviews conducted between 2008 (the year after USAID withdrew) and 2016, this paper shows that the long-term impact USAID had on civil society lay not within the formal institutions and organizations it supported, but in the resilience, creativity, and cooperation it fostered in the civil society sector. 相似文献
826.
Avery C. Edenfield Fredrik O. Andersson 《Voluntas: International Journal of Voluntary and Nonprofit Organizations》2018,29(5):1033-1043
This article examines how a social venture transitions from nascent to formal status and argues that the transformation of the organization set in motion by establishing formal boundaries is a deeply profound one. Drawing from the nonprofit and social entrepreneurship literature on what prompts and energizes individuals to initiate new not-for-profit ventures, and linking it to a notion of revolutionary crisis as organizations emerge and develop, we seek to illuminate and explore the tension, and its consequences, between nonprofit entrepreneurs and the organization they create as the new venture transitions from nascent to formal. We do this by presenting the results from an in-depth case study examining the gestation and boundary-forming phases of Robert’s Place Cooperative, a plucky start-up cooperative in a midsize Midwestern city. 相似文献
827.
Several models for studies related to tensile strength of materials are proposed in the literature where the size or length
component has been taken to be an important factor for studying the specimens’ failure behaviour. An important model, developed
on the basis of cumulative damage approach, is the three-parameter extension of the Birnbaum–Saunders fatigue model that incorporates
size of the specimen as an additional variable. This model is a strong competitor of the commonly used Weibull model and stands
better than the traditional models, which do not incorporate the size effect. The paper considers two such cumulative damage
models, checks their compatibility with a real dataset, compares them with some of the recent toolkits, and finally recommends
a model, which appears an appropriate one. Throughout the study is Bayesian based on Markov chain Monte Carlo simulation. 相似文献
828.
The variational approach to Bayesian inference enables simultaneous estimation of model parameters and model complexity. An interesting feature of this approach is that it also leads to an automatic choice of model complexity. Empirical results from the analysis of hidden Markov models with Gaussian observation densities illustrate this. If the variational algorithm is initialized with a large number of hidden states, redundant states are eliminated as the method converges to a solution, thereby leading to a selection of the number of hidden states. In addition, through the use of a variational approximation, the deviance information criterion for Bayesian model selection can be extended to the hidden Markov model framework. Calculation of the deviance information criterion provides a further tool for model selection, which can be used in conjunction with the variational approach. 相似文献
829.
S. Rao Jammalamadaka Md. Aleemuddin Siddiqi Kaushik Ghosh 《Journal of applied statistics》2009,36(6):621-631
Microtubules are part of the structural network within a cell's cytoplasm, providing structural support as well as taking part in many of the cellular processes. A large body of data provide evidence that dynamics of microtubules in a cell is reponsible for the performance of many critical cellular functions such as cell division. In this article, we study the effect of four different isoforms of a protein tau on microtubule dynamics using growth curve models. The results show that a linear growth curve model is sufficient to explain the data. Moreover, we find that a mutated version of a 3-repeat tau protein has a similar effect as a 4-repeat tau protein on microtubule dynamics. The latter findings conform with the biological understanding of the effect of the protein tau on microtubule dynamics. 相似文献
830.
Agustín Hernández Bastida José María Pérez Sánchez 《Journal of applied statistics》2009,36(8):853-869
The distribution of the aggregate claims in one year plays an important role in Actuarial Statistics for computing, for example, insurance premiums when both the number and size of the claims must be implemented into the model. When the number of claims follows a Poisson distribution the aggregated distribution is called the compound Poisson distribution. In this article we assume that the claim size follows an exponential distribution and later we make an extensive study of this model by assuming a bidimensional prior distribution for the parameters of the Poisson and exponential distribution with marginal gamma. This study carries us to obtain expressions for net premiums, marginal and posterior distributions in terms of some well-known special functions used in statistics. Later, a Bayesian robustness study of this model is made. Bayesian robustness on bidimensional models was deeply treated in the 1990s, producing numerous results, but few applications dealing with this problem can be found in the literature. 相似文献