The Changing Evidence Base of Social Science Research

I believe the evidence base of political science and the related social sciences are beginning an underappreciated but historic change. As a result, our knowledge of and practical solutions for problems of government and politics will begin to grow at an enormous rate — if we are ready. For the last half-century, we have learned about human populations primarily through sample surveys taken every few years, end-of-period government statistics, and in-depth studies of particular places, people, or events. These sources of information have served us well but, as is widely known, are limited: Survey research produces occasional snapshots of random selections of isolated individuals from unknown geographic locations, and the increases in cell phone use and growing levels of nonresponse are crumbling its scientific foundation. Aggregate government statistics are valuable, but in many countries are of dubious validity and are reported only with intentionally limited resolution or after obscuring valuable information. One-off in-depth studies are highly informative but for the most part do not scale, are not representative, and do not measure long-term change. In the next half-century, these existing data collection mechanisms will surely continue to be used and improved — such as with inexpensive web surveys, if the problems with their representativeness can be addressed — but they will be supplemented by the profusion of massive data bases already becoming available in many areas. Some produce extensive or continuous time information on individual political behavior and its causes, such as based on text sources (via automated information extraction from blogs, emails, speeches, government reports, and other web sources), electoral activity (via ballot images, precinct-level results, and individual-level registration, primary participation, and campaign contribution data), commercial activity (through every credit card and real estate transaction and via product RFIDs), geographic location (by carrying cell phones or passing through toll booths with Fastlane or EZPass transponders), health information (through digital medical records, hospital admittances, and accelerometers and other devices being included in cell phones), and others. Parts of the biological sciences are now effectively becoming social sciences, as developments in genomics, proteomics, metabolomics, and brain imaging produce huge numbers of person-level variables. Satellite imagery is increasing in scope, resolution, and availability. The internet is spawning numerous ways for individuals to interact, such as through social networking sites, social bookmarking, comments on blogs, participating in product reviews, and entering virtual worlds, all of which are possibilities for observation and experimentation. (Ensuring privacy and protection of personal information during the analyses to be conducted with this information will require considerable effort, care, and new work in research ethics, but should not be markedly more difficult than the now routine medical research involving experiments on human subjects with drugs and surgical procedures of unknown safety and efficacy.) The analogue-to-digital transformation of numerous devices people own makes them work better, faster, and less expensively, but also enables each one to produce data in domains not