# An Army of Me: Sockpuppets in Online Discussion Communities

## TL;DR

This paper analyzes sockpuppet behavior in online communities, revealing behavioral, linguistic, and social network differences, and develops methods for automatic detection of deceptive accounts.

## Contribution

It provides a comprehensive data-driven analysis of sockpuppets, introduces a taxonomy of deception, and applies findings to predict account linkage.

## Key findings

- Sockpuppets use more personal pronouns and have clustered networks.
- Pairs of sockpuppets are more likely to interact simultaneously.
- Deceptiveness varies, affecting detection strategies.

## Abstract

In online discussion communities, users can interact and share information and opinions on a wide variety of topics. However, some users may create multiple identities, or sockpuppets, and engage in undesired behavior by deceiving others or manipulating discussions. In this work, we study sockpuppetry across nine discussion communities, and show that sockpuppets differ from ordinary users in terms of their posting behavior, linguistic traits, as well as social network structure. Sockpuppets tend to start fewer discussions, write shorter posts, use more personal pronouns such as "I", and have more clustered ego-networks. Further, pairs of sockpuppets controlled by the same individual are more likely to interact on the same discussion at the same time than pairs of ordinary users. Our analysis suggests a taxonomy of deceptive behavior in discussion communities. Pairs of sockpuppets can vary in their deceptiveness, i.e., whether they pretend to be different users, or their supportiveness, i.e., if they support arguments of other sockpuppets controlled by the same user. We apply these findings to a series of prediction tasks, notably, to identify whether a pair of accounts belongs to the same underlying user or not. Altogether, this work presents a data-driven view of deception in online discussion communities and paves the way towards the automatic detection of sockpuppets.