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61.
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This article examines the relationship between the Europeanization process and the anti‐globalization agenda in Europe. Relying on the results of fieldwork research conducted since 2001 on the anti‐globalization demonstrations surrounding the European summits, it argues that these transnational protest movements are of a dual and, in part, contradictory nature. On the one hand, they have an agenda‐setting character, contributing to the formation of European public opinion. On the other hand, their influence in terms of agenda setting of European policy is constrained by their discourse style which bypasses or circumvents official discourse about European integration.  相似文献   
63.
Polluted soils have become a public health problem. While population exposure to soil pollutants is generally quantified using multimedia models, their estimations have not been validated, and studies that attempted to do so are scarce. The objective of the SOLEX study was to compare the predictions of pyrene exposure levels (converted into 1 hydroxypyrene) computed by several models with the results of urinary 1-hydropyrene (1-HOP) assays among 110 employees working at three sites polluted during their past use as manufactured gas plants. Four models were used: AERIS (Canada), CalTOX (California, USA), CLEA (UK), and HESP (The Netherlands). Three occupational exposure scenarios--with office, mixed, and outdoor workers--were constructed, based upon job activities during two measurement campaigns, one in winter and one in summer. The exposure levels estimated by the four models could differ markedly (from 7 up to 80 times) according to the exposure scenario. Also, the predominant exposure routes differed according to the model (direct soil ingestion for HESP and CalTOX, inhalation for AERIS, and dermal absorption for CLEA). The predictions of CalTOX are consistent with the 1-HOP measurements for all the scenarios. For HESP, the consistency is observed for the scenarios, office and mixed, for which the pyrene level in the soil is low. AERIS and CLEA yield results that are systematically above the 1-HOP measurements. This study confirms that validation of the models is crucial and points out to the need to proceed to assess components of the models that are the most influential using appropriate statistical analysis in combination with true field data.  相似文献   
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The variability of travel time modifies the rush hour traffic and the cost of commuting. The bottleneck model of road congestion with fixed peak-load demand is augmented of an additive random delay. When individuals have (α-β-γ) preferences, there exists a unique Nash equilibrium. The variability of travel time leads to departure rates that are spread more evenly over the rush hour than when travel times are deterministic. This equilibrium mechanism mitigates both congestion and the cost of unreliability. This implies that “single-traveler models,” which treat congestion as an exogenous phenomenon, overestimate the value of reliability for the rush hour. The application with the uniform or with the exponential distribution helps appraise the overestimation.  相似文献   
66.
ABSTRACT

Multi-state models describe the transitions people experience as life unfolds. The transition probabilities depend on sex, age, and attributes of the person and the context. Empirical evidence suggests that attributes that cannot be measured directly may at most be inferred from a long list of observable characteristics. A cluster-based, discrete-time multi-state model is presented, where transition probabilities are estimated simultaneously for several subpopulations of a heterogeneous population. The subpopulations are not defined a priori but are determined on the basis of similarities in behavior in order to determine which women exhibit similar characteristics with respect to method choice, method switch, discontinuation and subsequent resumption of contraceptive use. The data are from the life history calendar based on the Brazilian Demographic and Health Survey 1996. The parameters of the model are estimated using the EM algorithm. Seven subpopulations with heterogeneous transition probabilities are identified.  相似文献   
67.
Journal of Combinatorial Optimization - Modifying the topology of a network to mitigate the spread of an epidemic with epidemiological constant $$\lambda $$ amounts to the NP-hard problem of...  相似文献   
68.
This research examines how a firm's position in a coopetitive network (formed through cooperation among firms within an industry) influences the extent of the firm's competitive aggressiveness and market performance. The authors collected data on the competitive and cooperative actions of firms in the mobile telephone industry from 2000 to 2006, using structured content analysis of news reports. The results show that the centrality of a firm in a coopetitive network contributes to the firm's competitive aggressiveness through increased volume and variety of competitive actions. Further, the more central a firm is in the network, the greater is its market performance. Firms that undertake more volume and variety of competitive actions improve their market performance. Overall, these results show that being in a central position in a coopetition network is quite advantageous for the firm.  相似文献   
69.
Estimating function inference is indispensable for many common point process models where the joint intensities are tractable while the likelihood function is not. In this article, we establish asymptotic normality of estimating function estimators in a very general setting of nonstationary point processes. We then adapt this result to the case of nonstationary determinantal point processes, which are an important class of models for repulsive point patterns. In practice, often first‐ and second‐order estimating functions are used. For the latter, it is a common practice to omit contributions for pairs of points separated by a distance larger than some truncation distance, which is usually specified in an ad hoc manner. We suggest instead a data‐driven approach where the truncation distance is adapted automatically to the point process being fitted and where the approach integrates seamlessly with our asymptotic framework. The good performance of the adaptive approach is illustrated via simulation studies for non‐stationary determinantal point processes and by an application to a real dataset.  相似文献   
70.
We present a theoretical model on the processes that mediate and moderate the diversity-performance relationship. Past research on this topic—for example the categorization elaboration model (van Knippenberg et al. 2004)—has often focused on information elaboration as mediator. Complementing this cognitive perspective, we propose that group diversity can also stimulate group members to engage with each other emotionally, resulting in higher levels of empathy—an emotional state which arises from the comprehension and apprehension of fellow group members’ emotional state. Empathy, in turn, is likely to enhance performance through processes within a single group member and through processes between group members. At the core of the model lies the proposition that group- as well as individual-level empathy mediate the relationship between diversity of organizational units and the performance of individual members and groups at large (multilevel mediation). Furthermore, we specify moderating conditions for the relationship between diversity and empathy. Diversity beliefs and diversity climates are introduced as second-order moderators.  相似文献   
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