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In this article, we introduce tempered Mittag-Leffler Lévy processes (TMLLP). TMLLP is represented as tempered stable subordinator delayed by a gamma process. Its probability density function and Lévy density are obtained in terms of infinite series and Mittag-Leffler function, respectively. Asymptotic forms of the tails and moments are given. A step-by-step procedure of the parameters estimation and simulation of sample paths is given. We also provide main results available for Mittag-Leffler Lévy processes (MLLP) and some extensions which are not available in a collective way in a single article. Our results generalize and complement the results available on Mittag-Leffler distribution and MLLP in several directions. Further, the asymptotic forms of the moments of the first-exit times of the TMLLP are also discussed.  相似文献   
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This paper explores liminality, a concept receiving increased attention in management and organization studies and gaining prominence because of its capacity to capture the interstitial and temporary elements of organizing and work. The authors present a systematic review of the literature on liminality, covering 61 published papers, and undertake a critical analysis of how the concept of liminality has been used in prior research. This review reveals associations with three main themes: process; position; and place. For each theme, the authors identify the central research questions posed, while comparing individual and collective levels of analysis. During this process, the authors revisit several ideas central to the original, anthropological research on liminality, a perspective from which they suggest a rejuvenation of liminality research in management and organization studies. This paper argues for a greater focus on the liminal experience itself – especially its ritual and temporal dimensions – and for improving the comparative analysis of liminality following the three themes identified in this paper. The authors suggest that revising the agenda for liminality research along these lines could facilitate more informed responses to the challenges of an increasingly temporary and dynamic work life.  相似文献   
24.

Background

Second-degree tears are the most common form of perineal trauma occurring after vaginal birth managed by New Zealand midwives, although little is known about midwives’ perineal practice.

Aim

The aim of this study was to identify how midwives managed the last second-degree perineal tear they treated and the level to which their practice reflects National Institute for Health and Care Excellence guidelines.

Methods

An (anonymous) online survey was conducted over a six-week period in 2013. New Zealand midwives who self-identified as currently practising perineal management and could recall management of the last second-degree tear they treated were included in the analysis.

Findings

Of those invited, 645 (57.1% self-employed, 42.9% employed) were eligible and completed surveys. Self-employed midwives reported greater confidence (88.0% vs 74.4%, p < 0.001) and more recent experience (85.1% vs 57.4%, p < 0.001) with perineal repair than employed midwives. Midwives who left the last second-degree tear unsutured (7.3%) were more likely to report low confidence (48.9% vs 15.4%, p < 0.001) and less recent experience with repair (53.2% vs 24.7%, p < 0.001), and were less likely to report a digital-rectal examination (10.6% vs 49.0%, p < 0.001), compared to midwives who sutured. Care consistent with evidence-based guidelines (performing a digital-rectal examination, 59.4% vs 49.3% p = 0.005; optimal suturing techniques, 62.2% vs 48.7%, p = 0.001) was associated with recent perineal education.

Conclusions

Midwives’ management of the last second-degree perineal tear is variable and influenced by factors including: employment status, experience, confidence, and perineal education. There is potential for improvement in midwives’ management through increased uptake of evidence-based guidelines and through ongoing education.  相似文献   
25.
This paper examines the determinants of base pay and total incentive compensation packages of CEOs of biopharmaceutical firms that have recently gone public, and whether human capital and agency factors affect the market’s response to the initial public offering. We find that in terms of net proceeds, the IPO market appears to reward the firms that have founder-CEOs and CEOs with higher incentive compensation. CEOs with prior venture capital experience are associated with receiving higher incentive compensation, while CEOs with a greater ownership interest in the firm receive lower incentive compensation but higher salaries. CEOs of firms with a greater percentage of insiders are associated with lower salaries. The results should add to our understanding related to human capital and agency theories, as well as help firms and investors better understand and structure CEO compensation.  相似文献   
26.
Journal of Nonverbal Behavior - Past research has demonstrated that children understand distinct emotion concepts and can accurately recognize facial expressions of distinct emotions by a young...  相似文献   
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Random effects regression mixture models are a way to classify longitudinal data (or trajectories) having possibly varying lengths. The mixture structure of the traditional random effects regression mixture model arises through the distribution of the random regression coefficients, which is assumed to be a mixture of multivariate normals. An extension of this standard model is presented that accounts for various levels of heterogeneity among the trajectories, depending on their assumed error structure. A standard likelihood ratio test is presented for testing this error structure assumption. Full details of an expectation-conditional maximization algorithm for maximum likelihood estimation are also presented. This model is used to analyze data from an infant habituation experiment, where it is desirable to assess whether infants comprise different populations in terms of their habituation time.  相似文献   
29.
We propose testing procedures for the hypothesis that a given set of discrete observations may be formulated as a particular time series of counts with a specific conditional law. The new test statistics incorporate the empirical probability-generating function computed from the observations. Special emphasis is given to the popular models of integer autoregression and Poisson autoregression. The asymptotic properties of the proposed test statistics are studied under the null hypothesis as well as under alternatives. A Monte Carlo power study on bootstrap versions of the new methods is included as well as real-data examples.  相似文献   
30.
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