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arXiv · cond-mat/0206240

Macro- and micro-structure of trust networks

X. Guardiola·R. Guimera·A. Arenas·A. Diaz-Guilera·D. Streib·L. A. N. Amaral
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Abstract

A challenging problem in the social sciences is the characterization of the formation of ``social capital''. It is believed that societies with more social capital are more democratic and economically developed than societies with little social capital. However, social capital is a concept hard to quantify and measure in a ``real-word'' context. Here, we take advantage of an existing "web of trust'' between users of the "Pretty-Good-Privacy" (PGP) encryption algorithm, which is used in digital communication to ``sign'' documents so that the recipient knows for sure who the author is. Our analysis reveals the coexistence in the web of trust of a macro scale-free structure with micro strongly-connected cells in a complex network. We also show that when this network is intentionally attacked the scale-free structure rapidly disintegrates and that the resulting network is partitioned into a large number of small strongly-connected cells that are resilient to the intentional attack.

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X. Guardiola, R. Guimera, A. Arenas, A. Diaz-Guilera, D. Streib, L. A. N. Amaral. 2002-06-13. Macro- and micro-structure of trust networks. https://arxiv.org/abs/cond-mat/0206240

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