The Structure and Evolution of an Offline Peer-to-Peer Financial Network

TL;DR

This paper analyzes the structure and evolution of Venmo's offline social network, revealing its non-scale-free degree distribution, high connectivity, and small-world properties through static and dynamic measurements.

Contribution

It provides the first comprehensive analysis of Venmo's offline social network, highlighting its unique structural properties and evolution over time.

Findings

Degree distribution is not scale-free.

Giant component includes 99.9% of nodes.

Average path length is approximately 6 steps.

Abstract

In this work, we investigate the structure and evolution of a peer-to-peer (P2P) payment application. A unique aspect of the network under consideration is that the edges among nodes represent financial transactions among individuals who shared an offline social interaction. Our dataset comes from Venmo, the most popular P2P mobile payment service. We present a series of static and dynamic measurements that summarize the key aspects of any social network, namely the degree distribution, density and connectivity. We find that the degree distributions do not follow a power-law distribution, confirming previous studies that real-world social networks are rarely scale-free. The giant component of Venmo is eventually composed of 99.9% of all nodes, and its clustering coefficient reaches 0.2. Last, we examine the "topological" version of the small-world hypothesis and find that Venmo users are separated by a mean of 5.9 steps and a median of 6 steps.