Making Inferences About Elections and Public Opinion Using Incidentally Collected Data

Elections and public opinion scholarship has traditionally relied on datasets designed and collected for the specific purpose of measuring individuals’ political attitudes and behaviors. The Internet has greatly increased the availability of new non-purposefully or incidentally collected data (ICD), i.e. data that arises from citizen daily interactions on social media platforms, with search engines or civic technology platforms. ICD is now increasingly used in studies of public opinion, as well as to forecast elections and test causal relationships. While this work has shown that ICD can provide a valid basis for inference, it is clear that researchers need to treat such data with considerable caution in order to avoid making false claims. In this chapter we review the range and robustness of current research conducted with ICD and describe the main analytic challenges that researchers face in using ICD. Finally we show how, when properly handled, ICD can yield important new insights into political phenomenon.