Researchers have proposed an optimized ratio-type estimator that uses auxiliary attributes to estimate population means more ...

Use our calculator to determine your own survey sample size. Plus, we provide a quick explainer on how to use sampling to improve your customer experience program and rein in fees. “For a precise ...

Detailed information on Pew Research Center international survey methodology, such as mode of interview, sampling design, margin of error, and design effect, for each country we survey, organized by ...

As marine ecosystems change and technology advances, modernizing survey tools allows NOAA to maintain critical survey time series and deliver the best available science to support sustainable ...

A new telephone survey experiment finds that, despite major structural differences, an opinion poll drawn from a commercial voter file can produce results similar to those from a sample based on ...

NOAA Fisheries' Marine Recreational Information Program responds to questions about different types of survey errors, how they impact our estimates of recreational catch, and what we’re doing to ...