A Global Ex-vessel Fish Price Database: Construction and Applications

Synopsis We describe the first effort at creating a global ex-vessel fish price database, which is required for understanding the economic behavior of participants in the world’s fisheries. We demonstrate potential applications of the database by linking it to a spatially defined catch database, which makes it possible to attach landed values to species in both time and space. This is the first database available publicly where interested members of the public, researchers and managers can easily find and access ex-vessel prices of the world’s major commercial fish species. Preliminary results indicate that the average real price of a number of species have declined between 1950 and 2002. The estimated landed value of fish globally, in year 2000 dollars, was about US$24 billion in 1950. It increased steadily to about US$90 billion in the early 1970s, reached a peak of US$100 billion at the end of the 1980s, and declined to about US$80 billion in 2000. The top 15 fishing countries cumulatively account for 79% of total real landed value, with Japan leading, even though the value of its landings has been declining.      

Recursive utility with unbounded aggregators

A new framework is presented for the study of the existence and uniqueness of solutions to the Koopmans’ equation in the unbounded case, that is based on the contraction mapping approach. In the bounded below case with bounded consumption streams, uniqueness of the solution in the whole class of weak-star continuous utility functions is obtained. When the aggregator is unbounded below and/or consumption streams are unbounded, existence of a weak-star continuous solution is shown, and a simple criterium to check the sufficient conditions for existence is provided. Juan Pablo Rincón-Zapatero and Carlos Rodríguez-Palmero gratefully acknowledge financial support by the Ministerio de Educación y Ciencia and FEDER funds under Research Projects MTM2005-06534 and SEJ2005-08709/ECON, respectively, and by Consejería de Educación de la Junta de Castilla y León under Research Projects VA99/04 and VA017B05, respectively. This paper has substantially benefited from the comments of an anonymous referee. Particular and special thanks are due to Robert Becker for his very helpful comments and valuable suggestions.     

Credit Risk Research: Review and Agenda

This article provides a comprehensive review of scholarly research on credit risk measurement during the last 57 years applying bibliometric citation analysis and elaborates an agenda for future research. The bibliography is compiled using the Institute for Scientific Information (ISI) Web of Science (WOS) database and includes all articles with citations over the period 1960–2016. Specifically, the review is carried out using 1695 articles across 72 countries published in 442 journals by 2928 authors. The findings suggest that credit risk research is multifaceted and can be classified into six streams: (1) defaultable security pricing, (2) default intensity modeling, (3) comparative analysis of credit models, (4) comparative analysis of credit markets, (5) credit default swap (CDS) pricing, and (6) loan loss provisions. The article contributes through synthesizing and identifying existing as well as emerging research streams.     

GPS在土地测绘中的应用

在经济飞速发展的21世纪,土地测绘的技术也在快速发展着。因为该技术应用于各个领域,其中,GPS技术起到了十分关键的作用,不仅为各个领域的发展提供了充足的准备和保障,也就奠定了GPS成为最基础的科学的地位。     

Hybridizing local and generic information to model cropping system spatial distribution in an agricultural landscape

For quantitative water management, fine analysis of spatial and temporal interactions between cropping systems and water resources helps identify time and site-specific withdrawal situations. However, it is a methodological challenge to provide fine-resolution analyses at the scale of large watersheds used for crises management. In this study, we present a methodology based on multiple methods and mixed sources of information to finely model an agricultural landscape (AL) that represents the spatial distribution of cropping systems. Our approach is based on progressively hybridizing databases and local actors' and experts' knowledge to produce a spatially explicit and dynamic model. The Land Parcel Identification System database, which resulted from the European Common Agricultural Policy, is crucial for our method since it provides the spatial and temporal basis of our model (i.e., geographic delineation of islets and information about crop sequences). Local knowledge is used to identify factors determining spatial distribution of cropping systems and to build a generic model that simulates farmers' crop-management strategies. The model was qualitatively and quantitatively evaluated using a multi-agent simulation platform (MAELIA). We asked local experts on quantitative water management to evaluate the ability of the platform to reproduce intra- and inter-annual dynamics at different levels when using our model of the AL as input. The experts were satisfied with the results; they validated the predicted dynamics of the variables, and some discussed the objectivity of the values. We discuss the method’s contribution to current challenges in modeling large agricultural areas and the associated tradeoffs. The approach is promising for policy makers who wish to develop integrated, locally adapted land-management strategies.     

The failure of agri-environment measures to promote and conserve grassland biodiversity in Slovenia

The effectiveness of four grassland-specific agri-environment measures (AEM), implemented in the frame of the European Agricultural Fund for Rural Development (EAFRD) in the period 2007–2013 in Slovenia was studied. We questioned whether the measures – “extensive grassland maintenance”; “preservation of special grassland habitats”; “preservation of grassland habitats for butterflies” and “bird conservation in humid extensive meadows in Natura 2000 sites” did genuinely support the conservation (maintenance or improvement) of high nature value (HNV) grasslands in Slovenia. The HNV grasslands were defined on the basis of national fine-resolution field mapping of habitat types. Two main outcomes emerged: AEM did not reach the vast majority of HNV grasslands in Slovenia (only 3%); the proportion of HNV grassland area included in AEM was negligibly low (1). Moreover, even this very limited interest in AEM did not target only grasslands of HNV, but any permanent grasslands regardless of their conservation value: forty-one percent (41%) of the grassland areas included in the AEM were actually non-HNV grasslands (2). The absence of pre-selection criteria for grasslands along with an absence of monitoring of the effectiveness and efficiency of the measures and low interest in the subsidies among farmers, led to almost complete failure of the AEM to promote and conserve species-rich extensive grasslands in Slovenia between 2007 and 2013. Even with some minor differences, the same concept was maintained for the currently running EAFRD 2014–2020, which raises serious concern.     

Identifying and mapping the tourists⿿ perception of cultural ecosystem services: A case study from an Alpine region

Landscapes provide an array of services to society, from the provision of food and material, to the provision of cultural ecosystem services such as recreation, aesthetics or spirituality. Studies on cultural ecosystem services, however, remain rare and little is known about the spatial localisation of these services. In this study, we adopt and test a framework to identify and map the provision of cultural ecosystem services as perceived by tourists in an Alpine region, i.e. the region of South Tyrol in Italy. A photo-based questionnaire survey is combined with cartographical representations of landscape types to elicit hot and coldspot areas of cultural ecosystem service provision. We statistically test for influences of the land use type and the respondents' socio-demographic background on the tourists' perception of these services. The results show that different spatial patterns emerge for each of the investigated cultural ecosystem services depending on the distribution and extent of the landscape types to which they are related. In particular traditionally managed landscapes, small in extent and mainly scattered over large areas between 1000 and 2200 m a.s.l., are hotspot areas of aesthetic beauty, leisure activities and spirituality. In contrast, intensively managed landscapes, mainly located in the lowland plains of the study site, are considered to be more important for the provision of cultural heritage values. While the results suggest that land use type exerts the strongest influence upon tourists' perception, factors such as the respondents' perceived importance of the services, their gender, cultural background, environmental engagement and experience with the landscape play a significant but subordinate role. We conclude that the spatially explicit information about the provision of cultural ecosystem services can serve as a helpful basis for the design and further implementation of land use policies that acknowledge the high touristic value of traditionally used landscapes in mountain regions.     

The decade-long cryptocurrencies and the blockchain rollercoaster: Mapping the intellectual structure and charting future directions

Recent advances in science mapping allowed to analyze the entire intellectual structure of blockchain and cryptocurrencies in business-related disciplines to identify 174 academic articles as well as 1482 practitioner-oriented articles published since the inception of cryptocurrencies in 2008 to highlight key trends of the published outputs. The results demonstrate academic research done by 389 authors in 296 organizations based in 50 countries that only just initiated the conversation on four major streams of the literature—Bitcoin and cryptocurrencies; blockchain adoption; cryptocurrency and blockchain environment; and business model innovations. When comparing academic scholarship to practitioner-oriented literature, the results demonstrate that practitioners discussed investor-related themes, cryptocurrency intrinsic value, political-economic sphere, and the impact of cryptocurrency and blockchain technologies on the wider society in greater detail. As a result, a number of themes are identified and discussed that could align academic and practitioner interests and provide guidance for further research in this important field.     

测绘项目应注意安全生产

随着国家经济建设的快速发展,测绘作为各建设项目的基础工作越发重要,因为从业门槛较低和从业人员队伍庞大,所以测绘安全生产显得尤为重要,如何进行安全生产管理,值得每个从业人员深思。     

试论房地产面积测绘的结果和质量管理

本文通过对房地产面积测绘内容的分析,提出了相关的优化房地产面积测绘的措施及其质量管理。