(sdw19.uh.edu) About the workshop: Social decision making - from voting in a national election to investing in the stock market - is fundamental to human behavior. But we have limited ability to model, analyze or predict social decision making in realistic settings. There are several difficulties to overcome: i) The math is hard. Game theory provides a framework for analyzing social decision problems. But figuring out the “optimal” and the “stable” behaviors for any given problem is difficult, and often impossible. ii) People are not “rational". Real humans work with limited information and conflicting incentives when deciding how to behave. Understanding when and how humans depart from rationality is necessary to making reliable predictions. iii) The data are poor. Social media provides a large amount of very limited data. Most other spheres of human interaction are data sparse. Improving the science of social decision making has never been more vital, as we engage in urgent debates about how to construct and regulate spaces for public discourse, particularly online, and how the results of these regulations can impact our beliefs, actions and behavior. Our workshop will bring together researchers working in neuroscience, complex systems, game theory, evolutionary biology, collective animal behavior, psychology and behavioral economics to discuss how we can better coordinate theory, data and experiment to understand how people make social decisions.