His research uses randomized controlled experiments to help understand public opinion, voter behavior, and political representation. His work on these topics has appeared in the American Journal of Political Science, Political Analysis, and other academic journals, and been discussed in the New York Times, Washington Post, and many other media outlets. David has also helped design hundreds of experiments for the field, the web, email, mobile, and mail in the academic, political, and private sectors, including with the Analyst Institute, CREDO, and Google. David's latest research has focused on the effects of high-quality personal contacts on public opinion. He hopes to expand this work to climate.