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71.
72.
The length of repeated hypercalcemia free periods of patients with bone metastasis of breast cancer with at least one hypercalcemic event was modelled according to a generalized linear mixed model formulated in terms of transition probabilities and according to a latent variable model. In the former case the periods were assumed to be lognormally distributed with two variance components (patients and residue). In the latter case the conditional intensity given a patient was assumed to be the intensity of the Weibull distribution, while the random patient effect (frailty) was assumed to be drawn from a gamma distribution. In both cases the selection of only patients with at least one hypercalcemic event was taken into consideration. In both models the variance of the patient effect turned out to be negligible. For the second and later periods the Weibull appeared to fit better than the lognormal model. For the first period there was almost no information available.  相似文献   
73.
Organizations increasingly depend on employee efforts to innovate. However, the quality of relationships between leaders and employees may affect the recognition that employees receive for their innovative work behaviors. Drawing from a social cognition perspective, we tested a model in which leader–member exchange (LMX) moderates the impact of employee innovative work behavior on supervisory ratings of employee performance. Results from two multisource studies combining self, colleague, and supervisor ratings consistently showed that employees receive more favorable performance ratings by engaging in innovative work behavior when they have high‐quality LMX relationships. Moreover, we found that this interactive relationship was mediated by leader perceptions of innovative employee efforts, providing support for a moderated mediation model. Implications for the literatures on performance appraisal, LMX, and innovation are discussed.  相似文献   
74.
Guide to reform of higher education: a European perspective   总被引:2,自引:0,他引:2  
  相似文献   
75.
Urban water systems have to deal with the impacts of climate change. In response, urban water managers in the city of Rotterdam developed a new water management strategy combining the renewal of water infrastructure with neighborhood revitalization projects. A key factor was the recognition that additional water retention in existing urban areas could only be realized if these projects were linked to urban renewal programs. Moreover, it was acknowledged that through new water retention infrastructure the quality of the social environment of deteriorated neighborhoods could be restored. The results from this historical analysis show that this turn in thinking initiated a successful water policy innovation in Rotterdam, in which the urban water policy is used to solve other urban problems as well by improving the quality of the public amenity. This paper presents key factors that contributed to this process and provides recommendations to further advance the transformation of urban water management infrastructure and the link with spatial planning.  相似文献   
76.
Abstract

Objectives: Atrial fibrillation (AF) is the most common arrhythmia and a major marker of ischemic stroke risk. Early detection is crucial and, once diagnosed, anticoagulation therapy can be initiated to reduce stroke risk. The aim of this study was to assess the cost-effectiveness of employing an insertable cardiac monitor (ICM), BIOMONITOR, for the detection of AF compared to standard of care (SoC) ECG and Holter monitoring in patients with cryptogenic stroke, that is, stroke of unknown origin and where paroxysmal, silent AF is suspected.

Materials and methods: A Markov model was developed which consisted of five main health states reflecting the potential lifetime evolution of the AF disease: post cryptogenic stroke (index event), subsequent mild, moderate and severe stroke, and death. Sub-states were included to track a patient’s AF diagnostic status and the use of antiplatelet or anticoagulant therapy. AF detection was assumed to result in a treatment switch from aspirin to anticoagulants, except among those with a history of major bleeding. Detection yield and accuracy, clinical actions and treatment effects were derived from the literature and validated by an expert clinician. All relevant costs from a US Medicare perspective were included.

Results and conclusions: An ICM-based strategy was associated with a reduction of 37 secondary ischemic strokes per 1000 patients monitored compared with SoC. Total per-patient costs with an ICM were higher (US$90,052 vs. US$85,157) although stroke-related costs were reduced. The use of an ICM was associated with a base-case incremental cost-effectiveness ratio of US$18,487 per life year gained compared with SoC and US$25,098 per quality-adjusted life year gained, below established willingness-to-pay thresholds. The conclusions were found to be robust over a range of input values. From a US Medicare perspective the use of a BIOMONITOR ICM represents a cost-effective diagnostic strategy for patients with cryptogenic stroke and suspected AF.  相似文献   
77.
Bang-bang investment in a two-sector growth model with immobile capital is rational and leads to a unique and globally stable long-run equilibrium along a sliding trajectory. This steady state coincides with the stationary equilibrium in the traditional model with non-sector-specific capital.This article was written while the authors were visiting scholars at Cornell University. We gratefully acknowledge financial assistance from the Erasmus University Trust Fund and the Netherlands Scientific Organization. We would like to thank, without implicating, two anonymous referees, Martijn Herrmann, Jean-Marie Viaene, Claus Weddepohl, and the participants of seminars at the University of Maryland, the University of Montreal, and Erasmus University Rotterdam for perceptive remarks and useful comments. Jeroen Hinloopen and Rien Wagenvoort provided able graphical assistance. The views expressed in this article are those of the authors and not necessarily those of the World Bank.  相似文献   
78.
Sovereign wealth funds have become a prominent feature of the international financial landscape. However, legitimate concerns have been raised about these funds. Many of those concerns can be addressed via increased accountability and transparency by the funds. The Santiago Principles are a good start in doing so. My sovereign wealth funds scoreboard points to areas where these Principles can be improved. At the same time, the OECD effort to address concerns from the host‐country side has not resulted in the erection of new barriers to that form of cross‐border investment, but the OECD failed to reverse the creeping financial protectionism of the past decade. Because of their size and the source of their funding, some Asian funds stand out. As a result, those funds will be held to a higher standard of accountability and transparency.  相似文献   
79.
Strongly stable networks   总被引:3,自引:0,他引:3  
We analyze the formation of networks among individuals. In particular, we examine the existence of networks that are stable against changes in links by any coalition of individuals. We show that to investigate the existence of such strongly stable networks one can restrict focus on a component-wise egalitarian allocation of value. We show that when such strongly stable networks exist they coincide with the set of efficient networks (those maximizing the total productive value). We show that the existence of strongly stable networks is equivalent to core existence in a derived cooperative game and use that result to characterize the class of value functions for which there exist strongly stable networks via a “top convexity” condition on the value function on networks. We also consider a variation on strong stability where players can make side payments, and examine situations where value functions may be non-anonymous—depending on player labels.  相似文献   
80.
Abstract

HR managers have different beliefs about the nature, value, and instrumentality of talent—referred to as ‘talent philosophies’. In line with cognitive psychology, we reason that talent philosophies are similar to mental models that influence how HR managers interpret and use talent management (TM) practices within their organizations. In this article, we explore the prevalence of four different talent philosophies (exclusive/stable; exclusive/developable; inclusive/stable; inclusive/developable) in a sample of 321?HR managers. We then explore how talent philosophies relate to organizational context (i.e. size, ownership form, multinational orientation) as well as to HR managers’ perceptions of their organization’s TM practices. Cluster analysis corroborated the presence of the four talent philosophies in our dataset. All four talent philosophies were represented almost equally often in the overall dataset. Organizational size was found to be related to talent philosophies, such that HR managers who worked in smaller organizations were more likely to hold an inclusive talent philosophy. We also found support for the relationship between talent philosophies and perceptions of the exclusiveness or inclusiveness of the organization’s definition of talent, and its degree of workforce differentiation. Contrary to expectations, results did not support a link between talent philosophies and perceived talent identification criteria.  相似文献   
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