Mark Blumenthal and Natalie Jackson of Huffpost Pollster write: If you read polls in the news, you’re probably familiar with the term “margin of error.” What ...

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 ...

Learn how representative samples and random samples differ and why combining them minimizes sampling bias for accurate data.

Investopedia contributors come from a range of backgrounds, and over 25 years there have been thousands of expert writers and editors who have contributed. Thomas J. Brock is a CFA and CPA with more ...

Sampling is the process of collecting some data when collecting it all or analyzing it all is unreasonable. Before addressing why sampling still matters when massive amounts of data are available and ...