Université de Fribourg

K-core: Theories and applications

Kong, Yi-Xiu ; Shi, Gui-Yuan ; Wu, Rui-Jie ; Zhang, Yi-Cheng

In: Physics Reports, 2019, vol. 832, p. 1–32

With the rapid development of science and technology, the world is becoming increasingly connected. The following dire need for understanding both the relationships amongst individuals and the global structural characteristics brings forward the study of network sciences and many interdisciplinary subjects in recent years. As a result, it is crucial to have methods and algorithms that help us...

Université de Fribourg

Discoverers in scientific citation data

Shi, Gui-Yuan ; Kong, Yi-Xiu ; Yuan, Guang-Hui ; Wu, Rui-Jie ; Zeng, An ; Medo, Matúš

In: Journal of Informetrics, 2019, vol. 13, no. 2, p. 717–725

Identifying the future influential papers among the newly published ones is an important yet challenging issue in bibliometrics. As newly published papers have no or limited citation history, linear extrapolation of their citation counts—which is motivated by the well-known preferential attachment mechanism—is not applicable. We translate the recently introduced notion of discoverers to...

Université de Fribourg

Industry upgrading: recommendations of new products based on world trade network

Zhang, Wen-Yao ; Chen, Bo-Lun ; Kong, Yi-Xiu ; Shi, Gui-Yuan ; Zhang, Yi-Cheng

In: Entropy, 2019, vol. 21, no. 1, p. 39

GDP is a classic indicator of the extent of national economic development. Research based on the World Trade Network has found that a country’s GDP depends largely on the products it exports. In order to increase the competitiveness of a country and further increase its GDP, a crucial issue is finding the right direction to upgrade the industry so that the country can enhance its...

Université de Fribourg

Competition may increase social utility in bipartite matching problem

Kong, Yi-Xiu ; Yuan, Guang-Hui ; Zhou, Lei ; Wu, Rui-Jie ; Shi, Gui-Yuan

In: Complexity, 2018, p. -

Bipartite matching problem is to study two disjoint groups of agents who need to be matched pairwise. It can be applied to many real-world scenarios and explain many social phenomena. In this article, we study the effect of competition on bipartite matching problem by introducing conformity into the preference structure. The results show that a certain amount of competition can improve the...

Université de Fribourg

Instability in stable marriage problem: matching unequally numbered men and women

Shi, Gui-Yuan ; Kong, Yi-Xiu ; Chen, Bo-Lun ; Yuan, Guang-Hui ; Wu, Rui-Jie

In: Complexity, 2018, p. -

The goal of the stable marriage problem is to match by pair two sets composed by the same number of elements. Due to its widespread applications in the real world, especially the unique importance to the centralized matchmaker, a very large number of questions have been extensively studied in this field. This article considers a generalized form of the stable marriage problem, where different...

Université de Fribourg

The mathematics of non-linear metrics for nested networks

Wu, Rui-Jie ; Shi, Gui-Yuan ; Zhang, Yi-Cheng ; Mariani, Manuel Sebastian

In: Physica A: Statistical Mechanics and its Applications, 2016, vol. 460, p. 254–269

Numerical analysis of data from international trade and ecological networks has shown that the non-linear fitness–complexity metric is the best candidate to rank nodes by importance in bipartite networks that exhibit a nested structure. Despite its relevance for real networks, the mathematical properties of the metric and its variants remain largely unexplored. Here, we perform an analytic...

Université de Fribourg

Analysis of ground state in random bipartite matching

Shi, Gui-Yuan ; Kong, Yi-Xiu ; Liao, Hao ; Zhang, Yi-Cheng

In: Physica A: Statistical Mechanics and its Applications, 2016, vol. 444, p. 397–402

Bipartite matching problems emerge in many human social phenomena. In this paper, we study the ground state of the Gale–Shapley model, which is the most popular bipartite matching model. We apply the Kuhn–Munkres algorithm to compute the numerical ground state of the model. For the first time, we obtain the number of blocking pairs which is a measure of the system instability. We also show...