A behind-the-scenes blog about research methods at Pew Research Center. For our latest findings, visit pewresearch.org. Ask a survey methodologist to explain random sampling, or how non-probability ...

Greg DePersio has 13+ years of professional experience in sales and SEO and 3+ years as a writer and editor. Robert Kelly is managing director of XTS Energy LLC, and has more than three decades of ...

International surveys provide information about how people in different countries are thinking about issues, but polling in different parts of the world can be very challenging because what works in ...

Sampling is a technique in which samples are drawn at random (without any favor or bias). For this, suitable measures or procedures may be laid down and adopted according to the nature and ...