nep-net New Economics Papers
on Network Economics
Issue of 2014‒02‒15
four papers chosen by
Yi-Nung Yang
Chung Yuan Christian University

  1. Will Facebook save or destroy social capital? An empirical investigation into the effect of online interactions on trust and networks By Fabio Sabatini; Francesco Sarracino
  2. Allocating value among farsighted players in network formation By Nicolas CARAYOL; Remi DELILLE; Vincent VANNETELBOSCH
  3. A Novel Banking Supervision Method using a Threshold-Minimum Dominating Set By Gogas, Periklis; Papadimitriou , Theophilos; Matthaiou, Maria- Artemis
  4. Correlation and Network Topologies in Global and Local Stock Indices By Ashadun Nobi; Sungmin Lee; Doo Hwan Kim; Jae Woo Lee

  1. By: Fabio Sabatini; Francesco Sarracino
    Abstract: Studies in the social capital literature have documented two stylised facts: first, a decline in measures of social participation has occurred in many OECD countries. Second, and more recently, the success of social networking sites (SNSs) has resulted in a steep rise in online social participation. Our study adds to this body of research by conducting the first empirical assessment of how online networking affects two economically relevant aspects of social capital, i.e. trust and sociability. We find that participation in SNSs such as Facebook and Twitter has a positive effect on face-to-face interactions. However, social trust decreases with online interactions. Several interpretations of these findings are discussed.
    Keywords: Social participation; online networks; Facebook; Internet-mediated communication; social capital; broadband; digital divide
    JEL: C36 D85 O33 Z13
    Date: 2014–01–02
    Abstract: We propose a concept to study the stability of social and economic networks when players are farsighted and allocations are determined endogenously. A set of networks is a von Neumann-Morgenstern farsightedly stable set with bargaining if there exists an allocation rule and a bargaining threat such that (i) there is no farsighted improving path from one network inside the set to another network inside the set, (ii) from any network outside the set there is a farsighted improving path to some network inside the set, (iii) the value of each network is allocated among players so that players suffer or benefit equally from being linked to each other compared to the allocation they would obtain at their respective credible bargaining threat. We show that the set of strongly efficient networks is the unique von Neumann-Morgenstern farsightedly stable set with bargaining if the allocation rule is anonymous and component efficient and the value function is top convex. Moreover, the componentwise egalitarian allocation rule emerges endogenously.
    Keywords: Farsighted players, Stability, Equal bargaining power
    JEL: A14 C70 D20
    Date: 2014
  3. By: Gogas, Periklis (Democritus University of Thrace, Department of Economics); Papadimitriou , Theophilos (Democritus University of Thrace, Department of Economics); Matthaiou, Maria- Artemis (Democritus University of Thrace, Department of Economics)
    Abstract: A healthy and stable banking system resilient to financial crises is a prerequisite for sustainable growth. Minimization of a) the associated systemic risk and b) of the contagion effect in a banking crisis is a necessary condition to achieve this goal. The Central Bank is in charge of this significant undertaking via a close and detailed monitoring of the banking network that can significantly limit the outbreak of a crisis and a subsequent contagion. In this paper, we propose the use of an auxiliary monitoring system that is both efficient on the required resources and can promptly identify a set of banks that are in distress so that immediate and appropriate action can be taken by the supervising authority. We use the interrelations between banking institutions for efficient monitoring of the entire banking network employing tools from Complex Networks theory. In doing so, we introduce the Threshold Minimum Dominating Set (T-MDS). The T-MDS is used to identify the smallest most efficient subset of banks able to act as a) sensors of distress of a manifested banking crisis and b) provide a path of possible contagion. Moreover, at the discretion of the regulator, the methodology is versatile in providing multiple layers of supervision and monitoring by setting the appropriate threshold levels. We propose the use of this method as a supplementary monitoring tool in the arsenal of a Central Bank. Our dataset includes the 122 largest American banks in terms of their total assets. The empirical results show that when the T-MDS methodology is applied, we can have an efficient supervision of the whole banking network, by monitoring just a small subset of banks. We will show that, the proposed methodology is able to achieve an efficient overview of the 122 banks by only monitoring 47 T-MDS nodes.
    Keywords: Complex networks; Minimum Dominating Set; Banking supervision; Interbank loans
    JEL: D85 E58 G28
    Date: 2014–01–31
  4. By: Ashadun Nobi; Sungmin Lee; Doo Hwan Kim; Jae Woo Lee
    Abstract: This study examined how the correlation and network structure of 30 global indices and 145 local Korean indices belonging to the KOSPI 200 have changed during the 13-year period, 2000-2012. The correlations among the indices were calculated. The results showed that although the average correlations of the global indices increased with time, the local indices showed a decreasing trend except for drastic changes during crises. The average correlation of the local indices exceeded the global indices during the crises from 2000-2002, implying a strong correlation structure among the local indices during this period due to the detrimental effect of the dot-com bubble. The threshold networks (TN) were constructed in the observation time window by assigning a threshold value and determining the network topologies. A significant change in the network topologies was observed due to the financial crises in both markets. The Jaccard similarities were also determined using the common links of TNs. The TNs of the financial network were not consistent with the evolution of the time, and the successive TNs of the global indices were more similar than those of the successive local indices. Finally, the Jaccard similarities identified the change in the market state due to a crisis in both markets.
    Date: 2014–02

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