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 ...

The first video in Pew Research Center’s Methods 101 series helps explain random sampling – a concept that lies at the heart of all probability-based survey research – and why it’s important. Fresh ...

Systematic sampling is straightforward and low risk, offering better control. However, it may introduce sampling errors and ...

The first video in our “Methods 101” series is about random sampling, a concept that undergirds all probability-based survey research. Here’s how it works. Fresh data delivered Saturday mornings Thank ...