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131.
This analysis proposes new measures of rent creation and rent sharing and assesses their impact on productivity on cross‐country‐industry panel data. We find first that: (1) anticompetitive product market regulations positively affect rent creation and (2) employment protection legislation boosts hourly wages, particularly for low‐skill workers. However, we find no significant impact of this employment legislation on rent sharing, as the hourly wage increases are offset by a negative impact on hours worked. Second, using regulation indicators as instruments, we find that rent creation and rent sharing both have a substantial negative impact on total factor productivity. (JEL E22, E24, O30, L50, O43, O47, C23)  相似文献   
132.
The quest for a widely accepted definition of social enterprise (SE) has been a central issue in the last two decades. However, it only seems feasible today to identify a few criteria that were most debated: the specific role of individual social entrepreneurs, the place of social innovation, the search for market income and the issue of governance. The arena of conceptualization efforts should now be fed with more contributions starting from bottom-up approaches built upon a hypothesis that could be termed “the impossibility of a unified definition”. In this paper, we develop a theoretical framework combining principles of interest (mutual, general and capital interest) and resource mixes to identify institutional trajectories generating four major SE models. We then show that all four SE models may address the actual diversity of SE’s social missions. Finally, we suggest that such social missions may be enhanced differently depending on the respective governance mechanisms.  相似文献   
133.
Investigations of urbanization effects on birds have focused mainly on breeding traits expressed after the nest-building stage (e.g. first-egg date, clutch size, breeding success, and offspring characteristics). Urban studies largely ignored how and why the aspects of nest building might be associated with the degree of urbanization. As urban environments are expected to present novel environmental changes relative to rural environments, it is important to evaluate how nest-building behavior is impacted by vegetation modifications associated with urbanization. To examine nest design in a Mediterranean city environment, we allowed urban great tits (Parus major) to breed in nest boxes in areas that differed in local vegetation cover. We found that different measures of nest size or mass were not associated with vegetation cover. In particular, nests located adjacent to streets with lower vegetation cover were not smaller or lighter than nests in parks with higher vegetation cover. Nests adjacent to streets contained more pine needles than nests in parks. In addition, in nests adjacent to streets, nests from boxes attached to pine trees contained more pine needles than nests from boxes attached to other trees. We suggest that urban-related alterations in vegetation cover do not directly impose physical limits on nest size in species that are opportunistic in the selection of nesting material. However, nest composition as reflected in the use of pine needles was clearly affected by habitat type and the planted tree species present, which implies that rapid habitat change impacts nest composition. We do not exclude that urbanization might impact other aspects of nest building behaviour not covered in our study (e.g. costs of searching for nest material), and that the strengths of the associations between urbanization and nest structures might differ among study populations or species.  相似文献   
134.
Abstract

This article is inspired by some of the challenges faced by non-governmental organizations in the distribution of humanitarian relief to vulnerable rural communities. A major concern of these organizations is to warrant that relief is distributed in an impartial and transparent way, which gives rise to the notion of fairness. This article thus discusses the importance of fairness in relief distribution and how it can be defined, especially in a context where delivery of vital items must be ensured periodically. We also propose some performance indicators to measure fairness, which can be useful to organizations that are held accountable for the impartiality of their decisions. Finally, an empirical study of an academic case, inspired by a rural aid distribution problem, is used to analyse how different mathematical formulations may contribute in helping crisis managers integrate fairness or equity in their decisions.  相似文献   
135.
136.
The researches that specifically analyse the working conditions of teachers are few in the ergonomic literature. Our research relates more specifically to teachers of physical education and sports in french context of college. The research project described here includes both a quantitative exploratory survey (218 respondents) and qualitative case studies (interviews and observation), using the general framework of Activity Ergonomics. The results of this exploratory work tend to emphasize the importance of collective and organizational dimensions in the experience of teachers' physical education and sports. Specifically, in a perceived context of degradation of working conditions and accumulation of constraints, the collective and local ability to negotiate the various constraints on the activity appears to be a protective factor. This power to act, these margin of manoeuvre could be a relevant topic for future research.  相似文献   
137.
With their “Beyond Nonprofits: Re-conceptualizing the Third Sector”, Salamon and Sokolowski have made an important contribution to the ongoing debate on how to define the third sector. This Voluntas symposium brings together the comments of five leading scholars both supportive and critical of the new definition. The comments are based on a debate held at the conference of the International Society for Third Sector Research, in Stockholm in 2016.  相似文献   
138.
Leaf litter may be an important source of nutrients to stormwater and ultimately contribute to eutrophication of surface waters associated with urbanization. Thus, understanding decomposition and nutrient release from leaf litter that falls on impervious surfaces is important for stormwater management. However, few studies have examined leaf litter decomposition in the unique urban environment of the street gutter. We compared decomposition of leaf litter of five street tree species in a parking lot gutter in St. Paul, Minnesota, USA. In contrast to our expectations, comparisons with past studies revealed that litter decomposed more rapidly in the gutter than in nearby natural areas. And decomposition rates were as rapid as those measured in other urban settings (forests and streams), with most species losing 80 % of their initial mass after 1 year. Litter of most species had retained more than half of its initial N and P after 1 year. However, in contrast to N, litter P dynamics largely were uncoupled from litter mass dynamics, with litter P increasing and decreasing unpredictably over the year. Short-term (24 h) laboratory studies revealed that litter had the potential to lose a high fraction of its initial P, with high variation among species (from 27 to 88 %), and a smaller fraction of its initial N (<10 %) via leaching. Thus, street tree species may differ in their potential contributions to nutrients that are released during decomposition. Our results suggest that careful selection of street tree species and timely removal of litterfall have significant potential to reduce nutrient fluxes from streets to storm drains, particularly for P.  相似文献   
139.
This work is concerned with robustness in Principal Component Analysis (PCA). The approach, which we adopt here, is to replace the criterion of least squares by another criterion based on a convex and sufficiently differentiable loss function ρ. Using this criterion we propose a robust estimate of the location vector and introduce an orthogonality with respect to (w.r.t.) ρ in order to define the different steps of a PCA. The influence functions of a vector mean and principal vectors are developed in order to provide method for obtaining a robust PCA. The practical procedure is based on an alternative-steps algorithm.  相似文献   
140.
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