Our third Methods 101 video explores some of the ways that nonprobability surveys differ from traditional probability-based polls. How do pollsters conduct surveys online and what does that mean for ...

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 ...

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 ...