Among the changes: Smartphones and social media became the norm, church attendance fell, and same-sex marriage and legalizing marijuana gained support.
With fully a quarter of the U.S. adult population now relying solely on cell phone service, pollsters and other survey researchers face a difficult decision as to whether to include cell phones in their samples. A joint study by the Pew Research Center for the People & the Press and the Pew Internet & American Life Project takes an up-to-date look at the potential biases in findings based on landline-only surveys.