In modern information markets, buyers routinely combine signals from multiple sellers. We develop a model of ``portfolio competition'' to analyze this distinctive feature. We show that the combinability of information overturns standard oligopoly intuition. Unlike traditional markets,...

We develop a tractable model to study how AI and digital platforms impact the information ecosystem. News producers -- who create truthful or untruthful content that becomes a public good or bad -- earn revenue from consumer visits. Consumers search for information and differ in their ability to...

"The falling costs of collecting, storing, and processing data have allowed firms and governments to improve products and services. These same changes have also yielded databases containing detailed, individual-level data, raising privacy concerns. The Economics of Privacy summarizes the...

In this paper we build a formal model to study market environments where information is costly to acquire and is of use also to potential competitors. In such situations a market for information may form, where reports - of unverifiable quality - over the information acquired are sold. A...

I study how policymakers can access and act on the information about climate change damages that is dispersed throughout the economy. I analyze a new dynamic deposit-refund instrument (called "carbon shares") that I show can: i) efficiently price emissions conditional on information, ii)...

This paper reports on experiments testing the viability of markets for cheap talk information. We find that the poor quality of the information transmitted leads to a collapse of information markets. The reasons for this are surprising given the previous experimental results on cheap-talk games....