scholarly journals Structure and Evolution of the International Pesticide Trade Networks

2021 ◽  
Vol 9 ◽  
Author(s):  
Jian-An Li ◽  
Wen-Jie Xie ◽  
Wei-Xing Zhou
Keyword(s):  
International Trade ◽  
Dynamic Properties ◽  
Network Size ◽  
Clustering Coefficient ◽  
Trade Networks ◽  
The World ◽  
Local Clustering ◽  
Increasing Demand ◽  
Positive Correlations ◽  
Local Clustering Coefficient

To meet the increasing demand for food around the world, pesticides are widely used and will continue to be widely used in agricultural production to reduce yield losses and maintain product quality. International pesticide trade serves to reallocate the distribution of pesticides around the world. We investigate the statistical properties of the international trade networks of five categories of pesticides from the view angle of temporal directed and weighted networks. We observed an overall increasing trend in network size, network density, average in- and out-degrees, average in- and out-strengths, temporal similarity, and link reciprocity, indicating that the rising globalization of pesticides trade is driving the networks denser. However, the distributions of link weights remain unchanged along time for the five categories of pesticides. In addition, all the networks are disassortatively mixed because large importers or exporters are more likely to trade with small exporters or importers. We also observed positive correlations between in-degree and out-degree, in-strength and out-strength, link reciprocity and in-degree, out-degree, in-strength, and out-strength, while node’s local clustering coefficient is negatively related to in-degree, out-degree, in-strength, and out-strength. We show that some structural and dynamic properties of the international pesticide trade networks are different from those of the international trade networks, highlighting the presence of idiosyncratic features of different goods and products in the international trade.

Foreign exchange earnings of the countries of the world from international trade in fruit and berry products

2021 ◽  
pp. 45-56
Author(s):  
Rafail R. Mukhametzyanov ◽  
◽  
Nikolay G. Platonovskiy ◽  
Akhmed M. Khezhev ◽  
Tatiyana V. Ostapchuk ◽  
...  
Keyword(s):  
International Trade ◽  
Foreign Exchange ◽  
Import Substitution ◽  
World Order ◽  
Climatic Conditions ◽  
The European Union ◽  
The World ◽  
Increasing Demand ◽  
Processed Products ◽  
The Stability

In the context of the modern global financial world order, an important element of the stability of the national monetary unit of the overwhelming majority of countries in the world, especially developing countries, is foreign exchange earnings. For some countries with favorable natural and climatic conditions, the production, processing and export of agricultural products plays a significant role in the overall structure of foreign exchange earnings in the country. The constantly increasing demand from consumers for fruits, berries, nuts and their processed products allows economic entities of national fruit and berry subcomplexes to increase the volume of growing and exporting these types of products. This study analyzes the change in the volume of exports and imports of fruit and berry products in value terms for the period 2010-2019. It is revealed that some states, being the largest exporters of fruits, berries, nuts and products of their processing, occupy significant positions in the import of these types of products from abroad. Based on the author’s calculations, the top 30 countries of the world have been compiled in terms of net foreign exchange earnings from international trade in this type of product. According to this indicator, the first line with a level of $ 7.506 billion was occupied by Spain, while it increased it by $ 1.675 billion over 10 years. As for Russia, despite the counter-sanctions against the countries of the European Union and some other countries of the world, as well as the ongoing policy of import substitution, including in domestic gardening, it continues to be one of the main importers of fruits, berries, nuts and their processing products in the world. Thus, our country supports both foreign producers and other commercial structures that carry out the processes of commodity circulation of fruit and berry products, and the receipt of foreign exchange earnings in these powers.

scholarly journals Counting Triangles in Power-Law Uniform Random Graphs

10.37236/9239 ◽  
2020 ◽  
Vol 27 (3) ◽  
Author(s):  
Pu Gao ◽  
Remco Van der Hofstad ◽  
Angus Southwell ◽  
Clara Stegehuis
Keyword(s):  
Random Graphs ◽  
Power Law ◽  
Degree Sequence ◽  
Clustering Coefficient ◽  
Linear Functions ◽  
Configuration Model ◽  
Local Clustering ◽  
Asymptotic Number ◽  
Multiple Edges ◽  
Local Clustering Coefficient

We count the asymptotic number of triangles in uniform random graphs where the degree distribution follows a power law with degree exponent $\tau\in(2,3)$. We also analyze the local clustering coefficient $c(k)$, the probability that two random neighbors of a vertex of degree $k$ are connected. We find that the number of triangles, as well as the local clustering coefficient, scale similarly as in the erased configuration model, where all self-loops and multiple edges of the configuration model are removed. Interestingly, uniform random graphs contain more triangles than erased configuration models with the same degree sequence. The number of triangles in uniform random graphs is closely related to that in a version of the rank-1 inhomogeneous random graph, where all vertices are equipped with weights, and the probabilities that edges are present are moderated by asymptotically linear functions of the products of these vertex weights.

scholarly journals International trade in services: The role of international shipping

2007 ◽  
Vol 59 (2-3) ◽  
pp. 376-399
Author(s):  
Ivana Popovic-Petrovic
Keyword(s):  
International Trade ◽  
Trade In Services ◽  
National Interests ◽  
Transportation Services ◽  
The Past ◽  
Wide Range ◽  
The World ◽  
Increasing Demand ◽  
Merchandise Trade

The General Agreement on Trade in Services (GATS) is one of the World Trade Organization's most important agreements. This accord is the first and only set of multilateral rules covering international trade in services. It is a framework for international trade in services and a legal basis for resolving conflicting national interests. For the past two decades, trade in services has grown faster than merchandise trade. Currently, they represent more than two thirds of the World Gross Domestic Product. As the term services covers a wide range of intangible and heterogeneous products and activities, there has been an increasing demand for detailed, relevant and internationally comparable statistical information on trade in services. In the last ten years, the share of transportation services in international trade in commercial services was steady and amounted to about one quarter.

scholarly journals Overlapping Structures Detection in Protein-Protein Interaction Networks Using Community Detection Algorithm Based on Neighbor Clustering Coefficient

2021 ◽  
Vol 12 ◽  
Author(s):  
Yan Wang ◽  
Chen Qiong ◽  
Lili Yang ◽  
Sen Yang ◽  
Kai He ◽  
...  
Keyword(s):  
Community Detection ◽  
Detection Algorithm ◽  
Clustering Coefficient ◽  
Functional Modules ◽  
Seed Selection ◽  
Protein Protein Interaction ◽  
Ppi Networks ◽  
Local Clustering ◽  
Community Detection Algorithm ◽  
Local Clustering Coefficient

With the rapid development of bioinformatics, researchers have applied community detection algorithms to detect functional modules in protein-protein interaction (PPI) networks that can predict the function of unknown proteins at the molecular level and further reveal the regularity of cell activity. Clusters in a PPI network may overlap where a protein is involved in multiple functional modules. To identify overlapping structures in protein functional modules, this paper proposes a novel overlapping community detection algorithm based on the neighboring local clustering coefficient (NLC). The contributions of the NLC algorithm are threefold: (i) Combine the edge-based community detection method with local expansion in seed selection and the local clustering coefficient of neighboring nodes to improve the accuracy of seed selection; (ii) A method of measuring the distance between edges is improved to make the result of community division more accurate; (iii) A community optimization strategy for the excessive overlapping nodes makes the overlapping structure more reasonable. The experimental results on standard networks, Lancichinetti-Fortunato-Radicchi (LFR) benchmark networks and PPI networks show that the NLC algorithm can improve the Extended modularity (EQ) value and Normalized Mutual Information (NMI) value of the community division, which verifies that the algorithm can not only detect reasonable communities but also identify overlapping structures in networks.

scholarly journals Disparity of clustering coefficients in the Holme‒Kim network model

2018 ◽  
Vol 50 (3) ◽  
pp. 918-943
Author(s):  
R. I. Oliveira ◽  
R. Ribeiro ◽  
R. Sanchis
Keyword(s):  
Random Graph ◽  
Network Model ◽  
Slow Rate ◽  
Clustering Coefficient ◽  
Concentration Inequality ◽  
Free Graph ◽  
Scale Free ◽  
Local Clustering ◽  
Clustering Coefficients ◽  
Local Clustering Coefficient

Abstract The Holme‒Kim random graph process is a variant of the Barabási‒Álbert scale-free graph that was designed to exhibit clustering. In this paper we show that whether the model does indeed exhibit clustering depends on how we define the clustering coefficient. In fact, we find that the local clustering coefficient typically remains positive whereas global clustering tends to 0 at a slow rate. These and other results are proven via martingale techniques, such as Freedman's concentration inequality combined with a bootstrapping argument.

scholarly journals Characterizing several properties of high-dimensional random Apollonian networks

2020 ◽  
Vol 8 (4) ◽  
Author(s):  
Panpan Zhang
Keyword(s):  
Small World ◽  
Wiener Index ◽  
Clustering Coefficient ◽  
Probabilistic Methods ◽  
High Dimensional ◽  
Analytic Combinatorics ◽  
Local Clustering ◽  
Clustering Property ◽  
Small World Property ◽  
Local Clustering Coefficient

Abstract In this article, we investigate several properties of high-dimensional random Apollonian networks, including two types of degree profiles, the small-world effect (clustering property), sparsity and three distance-based metrics. The characterizations of the degree profiles are based on several rigorous mathematical and probabilistic methods, such as a two-dimensional mathematical induction, analytic combinatorics and Pólya urns, etc. The small-world property is uncovered by a well-developed measure—local clustering coefficient and the sparsity is assessed by a proposed Gini index. Finally, we look into three distance-based properties; they are total depth, diameter and Wiener index.

scholarly journals Random intersection graphs with communities

2021 ◽  
Vol 53 (4) ◽  
pp. 1061-1089
Author(s):  
Remco van der Hofstad ◽  
Júlia Komjáthy ◽  
Viktória Vadon
Keyword(s):  
Weak Convergence ◽  
Internal Structure ◽  
Degree Distribution ◽  
Clustering Coefficient ◽  
Intersection Graphs ◽  
Structure Of Communities ◽  
Local Clustering ◽  
Model Networks ◽  
Local Weak Convergence ◽  
Local Clustering Coefficient

AbstractRandom intersection graphs model networks with communities, assuming an underlying bipartite structure of communities and individuals, where these communities may overlap. We generalize the model, allowing for arbitrary community structures within the communities. In our new model, communities may overlap, and they have their own internal structure described by arbitrary finite community graphs. Our model turns out to be tractable. We analyze the overlapping structure of the communities, show local weak convergence (including convergence of subgraph counts), and derive the asymptotic degree distribution and the local clustering coefficient.

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