Survey sampling and estimation methods form the cornerstone of modern statistical inference, underpinning research across the social, medical, and natural sciences. At their heart, these methods ...

PROC SURVEYSELECT provides a variety of methods for selecting probability-based random samples. With probability sampling, each unit in the survey population has a known, positive probablity of ...

The COVID-19 pandemic has infected over 38 million people around the world and is showing no signs of going away any time soon. Researchers worldwide are frantically working on developing an effective ...

One possible explanation for the variability in estimates across the different nonprobability samples is the range of methods that online sample vendors employ. They differ on recruitment, weighting ...

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

— -- ABC News polls of the general population are conducted by telephone among a random national sample of adults age 18 and over. Sampling and data collection for most of these polls is ...