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Much effort has been dedicated to fighting wildlife crime with modest results. This paper focuses on marine wildlife crime, which suffers from a certain level of neglect due to terrestrial bias (a predominant focus on land animals). Despite legislative and enforcement efforts, there has been little integration of marketing techniques to curtail marine wildlife crime. For these reasons, we set out to study current issues surrounding marine wildlife crime by conducting interviews with three experts in areas of marine education, research, and legislation. The interviews provide an overview of the threats to marine wildlife, aid in the development of a classification of marine wildlife crime, and provide strategies as to what marketing actions may be useful to reduce it.  相似文献   
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Participating in leisure activities provides important benefits for all people. However, there is a substantial reduction of (green) leisure opportunities in cities, and the green spaces that are available often are poorly accessible. The purpose of this study is to analyze the diversity of participation in various types of leisure activities and to determine the relationship between leisure activity participation and characteristics of the residential environment depending on socio-demographic characteristics. Diary data from 803 respondents living in the Eindhoven region in the Netherlands were used. Four segments were identified that differ regarding their leisure activity participation, and a modest impact of green space accessibility was found.  相似文献   
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Living in inadequate housing conditions not only supposes a failure of a basic functioning. It also has effects on other essential aspects of well-being such as health. This study questions to what extent living in poor housing conditions can determine individuals’ health status once the possible influence of other factors is controlled for. By estimating a logistic model with individual effects and a housing deprivation index based on a latent variable model, we reach a number of relevant conclusions concerning the relationship between these two different dimensions of multidimensional well-being. We find a negative effect of housing deprivation on the individuals’ health, both when housing conditions are introduced in a disaggregated manner in the model and when they are combined in a latent variable.  相似文献   
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Journal of Regulatory Economics - A number of studies suggest that price cap regulation may reduce the quality of the regulated good. This paper analyzes the impact on drinking water quality of a...  相似文献   
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Studies of improved seed adoption in developing countries are almost always based on household surveys and are premised on the assumption that farmers can accurately self-report their use of improved seed varieties. However, recent studies suggest that farmers’ reports of seed varieties planted, or even whether the seed is local or improved, are sometimes inconsistent with the DNA fingerprinting results of those crops. We use household survey data from Tanzania to test the alignment between farmer-reported and DNA-identified maize seed types planted. In the sample, 70% of maize seed observations are correctly reported as local or improved, while 16% are type I errors (falsely reported as improved) and 14% are type II errors (falsely reported as local). Type I errors are more likely to have been sourced from other farmers, rather than formal channels. An analysis of input use, including seed, fertiliser, and labour allocations, reveals that farmers tend to treat improved maize differently, depending on whether they correctly perceive it as improved. This suggests that errors in farmers’ seed type awareness may translate into suboptimal management practices. The average yield of seed that is correctly identified as improved is almost 700 kg per hectare greater than that of type I errors. This indicates that investments in farmers’ access to information, seed labelling, and seed system oversight are needed to complement investments in seed variety development.  相似文献   
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Non-negative matrix factorisation (NMF) is an increasingly popular unsupervised learning method. However, parameter estimation in the NMF model is a difficult high-dimensional optimisation problem. We consider algorithms of the alternating least squares type. Solutions to the least squares problem fall in two categories. The first category is iterative algorithms, which include algorithms such as the majorise–minimise (MM) algorithm, coordinate descent, gradient descent and the Févotte-Cemgil expectation–maximisation (FC-EM) algorithm. We introduce a new family of iterative updates based on a generalisation of the FC-EM algorithm. The coordinate descent, gradient descent and FC-EM algorithms are special cases of this new EM family of iterative procedures. Curiously, we show that the MM algorithm is never a member of our general EM algorithm. The second category is based on cone projection. We describe and prove a cone projection algorithm tailored to the non-negative least square problem. We compare the algorithms on a test case and on the problem of identifying mutational signatures in human cancer. We generally find that cone projection is an attractive choice. Furthermore, in the cancer application, we find that a mix-and-match strategy performs better than running each algorithm in isolation.  相似文献   
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ABSTRACT

Previous studies on the impact of the new protectionist stance of the United States have focused mainly on the imposition of the controversial border tax. This research advances the understanding of the possible impacts of the tightening of the rules of origin and the imposition of the most-favored nation tariffs on manufacturing companies. The findings show a negative impact from the protectionist measures on businesses by increasing costs per unit and decreasing the gross margin. The results suggest that those additional costs could be passed on to the final buyers, raising the price level by more than previously assumed.  相似文献   
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