Stratified random sampling is a method of sampling that divides a population into smaller groups that form the basis of test samples.

Melissa Horton is a financial literacy professional. She has 10+ years of experience in the financial services and planning industry. Robert Kelly is managing director of XTS Energy LLC, and has more ...

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 ...

Sampling is the process of creating a small unbiased population to be used in a test or experiment. The sample removes the impractical idea of surveying everyone in a market or a population. Random ...

The rise of internet polling makes it more feasible to publish estimates for Asian Americans. But these estimates offer a limited view. What does the migration to online polling mean for the country’s ...