22,355 research outputs found

    European Regional Science: Between Economy of Culture and Economy of Catastrophes (Review of the ERSA 2005 Amsterdam Congress Reports)

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    ERSA Congress can be seen as laboratory of ideas with broad representation not only European, but also scientists from US, Japan, Korea, Brazil, African and Asian countries. With very high speed new thoughts and phenomena from the European regional scientific community appear on the stages of the ERSA annual Congresses. Three new features were characteristic for the 2005 ERSA Congress in comparison with the previous ones. First, special focus on the factors of density in the regional development. That was not surprising as the meeting was held in the city of Amsterdam with the highest density in Europe where land and space are scarce goods. Second, integrative tendencies in attempt to use natural factors to explain traditional phenomena of the regional science. Issues of land and water management coincide with economic growth and regional development in many reports. Third, for the first time theme of networks and network society was embedded in many sections of the Congress and in the very title of the Congress itself. All these aspects as participants demonstrated could be positive creative factors increasing cultural assets of the European regions, efficiency of the knowledge transfer, leisure activities; or negative as the source of disaster and risk for human beings. Density factors (lack of people or lack of space?) divide European regional science into two sciences – urban for the populated regions and regional for the territories scarcely populated with very different themes, methods and tools of research. Housing markets, urban sprawl and commuting patterns are popular topics in the first case; labour markets and human capital in the second case. New Economic Geography models work smoothly in the first regions but are inappropriate in the second. Competition is harder in the labour markets of the populated regions but is softer in the regions with scattered population where it is substituted by the forces of cooperation. Contemporary regional society can be sustainable only as network society. In the reports networks were examined on different levels: a) as transportation networks in the investment national or interregional projects; b) as policentricity urban structures replacing Cristaller’s hierarchy of central places; c) as public-public, public-private partnerships combining public and private stakeholders in the decision-making process. Transition of the European regions from the industrial to network/service has begun 25 years ago. Position of the concrete region on this route determines clearly the type and intensity of its problem and research agenda. The more advanced is the region or nation on this route the more often terms like “reinventâ€, “rethinkâ€, “revisited†are used in the scientific community. Rediscovery of the old concepts, definitions, essence (as Amsterdam Congress demonstrated) is very creative and challenging process of the post-industrial regional science.

    Evolutionary model type selection for global surrogate modeling

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    Due to the scale and computational complexity of currently used simulation codes, global surrogate (metamodels) models have become indispensable tools for exploring and understanding the design space. Due to their compact formulation they are cheap to evaluate and thus readily facilitate visualization, design space exploration, rapid prototyping, and sensitivity analysis. They can also be used as accurate building blocks in design packages or larger simulation environments. Consequently, there is great interest in techniques that facilitate the construction of such approximation models while minimizing the computational cost and maximizing model accuracy. Many surrogate model types exist ( Support Vector Machines, Kriging, Neural Networks, etc.) but no type is optimal in all circumstances. Nor is there any hard theory available that can help make this choice. In this paper we present an automatic approach to the model type selection problem. We describe an adaptive global surrogate modeling environment with adaptive sampling, driven by speciated evolution. Different model types are evolved cooperatively using a Genetic Algorithm ( heterogeneous evolution) and compete to approximate the iteratively selected data. In this way the optimal model type and complexity for a given data set or simulation code can be dynamically determined. Its utility and performance is demonstrated on a number of problems where it outperforms traditional sequential execution of each model type

    A cloud-based enhanced differential evolution algorithm for parameter estimation problems in computational systems biology

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    This is a post-peer-review, pre-copyedit version of an article published in Cluster Computing. The final authenticated version is available online at: https://doi.org/10.1007/s10586-017-0860-1[Abstract] Metaheuristics are gaining increasing recognition in many research areas, computational systems biology among them. Recent advances in metaheuristics can be helpful in locating the vicinity of the global solution in reasonable computation times, with Differential Evolution (DE) being one of the most popular methods. However, for most realistic applications, DE still requires excessive computation times. With the advent of Cloud Computing effortless access to large number of distributed resources has become more feasible, and new distributed frameworks, like Spark, have been developed to deal with large scale computations on commodity clusters and cloud resources. In this paper we propose a parallel implementation of an enhanced DE using Spark. The proposal drastically reduces the execution time, by means of including a selected local search and exploiting the available distributed resources. The performance of the proposal has been thoroughly assessed using challenging parameter estimation problems from the domain of computational systems biology. Two different platforms have been used for the evaluation, a local cluster and the Microsoft Azure public cloud. Additionally, it has been also compared with other parallel approaches, another cloud-based solution (a MapReduce implementation) and a traditional HPC solution (a MPI implementation)Ministerio de Economía y Competitividad; DPI2014-55276-C5-2-RMinisterio de Economía y Competitividad; TIN2013-42148-PMinisterio de Economía y Competitividad; TIN2016-75845-PXunta de Galicia ; R2016/045Xunta de Galicia; GRC2013/05

    Migration, Unemployment and Net Benefits of Inbound Tourism in a Developing Country

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    International tourism is increasingly viewed as one of the best opportunities for a sustainable economic and social development of developing countries. There is also an increasing concern from public policy makers as to whether mass tourism coastal resorts can play a catalytic role in the overall economic development and improve the real income of their community. In this paper, we present a general equilibrium model which explicitly takes into consideration specific features of some developing countries (e.g. coastal tourism, dual labour market, unemployment, migrations, competition between agriculture and tourism for land) to analyse the ways by which an inbound tourism boom affects this kind of country, in particular its real income. We define the conditions under which an inbound tourism boom makes developing countries residents worse off.Economic impacts, General equilibrium model, Inbound tourism, Migration, Unemployment, Developing countries

    International trade negotiations and the trans-border movement of people: A review of the literature

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    We review the international and New Zealand literatures on the two-way interaction between international migration and agreements designed to enhance cross-border trade or investment. Benefits and costs of migration, to the extent that these may feature in trade and migration negotiations, are discussed. While trade and migration can be substitutes in some contexts, they will be complements in other contexts. Liberalisation of services and the movement of people are likely to offer much more significant gains than liberalisation of remaining barriers to goods trade. Significant scope for liberalisation under GATS mode 4 (the movement of natural persons) may remain. However, temporary migration is already promoted on a unilateral and bilateral basis within immigration policy frameworks that may provide greater flexibility than GATS mode 4. With respect to both trade and migration, the more diverse the exchanging countries are, the greater the economic benefits tend to be. However, greater diversity may also imply greater social costs. This paradox of diversity needs to be addressed through appropriate social policies accompanying enhanced temporary and permanent migration

    Gravitymodels of interprovincial migration flows in Canada with hierarchical multifactor structure

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    Following recent contributions on migration flows, we contribute to the literature by relaxing restrictions on how multilateral resistance to migration (MRM) may affect province-pair-specific migration flows. We follow recent advancements in the three dimensional (3D) panel data models with a hierarchical multifactor structure and develop the more flexible specification for MRM. In addition to including unobserved global (country) factors with province-pair-specific coefficients, we can control for local origin (destination)-specific factors that have heterogeneous effects on destinations (origins). We apply the 3DCCE estimator advanced by Kapetanios et al. (J Econom, 2020) to an analysis of the determinants of interprovincial migration flows in Canada from 1976 to 2014. In particular, we find that the recent rise in the internal migration flows, registered in Canada from 2009 onwards, is more likely to be associated with the relative income inequality and network presence rather than the conventional long-run determinants such as income and unemployment differentials
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