Knowledge through social networks: Accuracy, error, and polarisation.

This paper examines the fundamental problem of testimony. Much of what we believe to know we know in good part, or even entirely, through the testimony of others. The problem with testimony is that we often have very little on which to base estimates of the accuracy of our sources.

How Communication Can Make Voters Choose Less Well.

With the advent of social media, the last decade has seen profound changes to the way people receive information. This has fueled a debate about the ways (if any) changes to the nature of our information networks might be affecting voters' beliefs about the world, voting results, and, ultimately, democracy. At the same time, much discussion in the public arena in recent years has concerned the notion that ill-informed voters have been voting against their own self-interest.

How Good Is Your Evidence and How Would You Know?

This paper examines the basic question of how we can come to form accurate beliefs about the world when we do not fully know how good or bad our evidence is. Here, we show, using simulations with otherwise optimal agents, the cost of misjudging the quality of our evidence. We compare different strategies for correctly estimating that quality, such as outcome- and expectation-based updating.