# Gaps in Information Access in Social Networks

## TL;DR

This paper addresses the issue of unequal information access in social networks by proposing a maximin welfare approach to ensure fairer dissemination, analyzing its theoretical properties, computational challenges, and practical effectiveness.

## Contribution

It introduces the maximin social welfare function for fair information spread, proving its effectiveness in reducing access gaps and providing practical algorithms.

## Key findings

- Maximin welfare constrains access gaps effectively.
- Maximizing expected reach does not reduce access disparities.
- A simple greedy strategy performs well empirically.

## Abstract

The study of influence maximization in social networks has largely ignored disparate effects these algorithms might have on the individuals contained in the social network. Individuals may place a high value on receiving information, e.g. job openings or advertisements for loans. While well-connected individuals at the center of the network are likely to receive the information that is being distributed through the network, poorly connected individuals are systematically less likely to receive the information, producing a gap in access to the information between individuals. In this work, we study how best to spread information in a social network while minimizing this access gap. We propose to use the maximin social welfare function as an objective function, where we maximize the minimum probability of receiving the information under an intervention. We prove that in this setting this welfare function constrains the access gap whereas maximizing the expected number of nodes reached does not. We also investigate the difficulties of using the maximin, and present hardness results and analysis for standard greedy strategies. Finally, we investigate practical ways of optimizing for the maximin, and give empirical evidence that a simple greedy-based strategy works well in practice.