Note: This report was updated on Dec. 30, 2015 to reflect the January-July 2015 National Health Interview Survey estimates released on December 1, 2015. Telephone surveys face numerous challenges, but ...

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 ...

Targeting matters most. Surveying the wrong audience can lead to misleading data and poor decisions, even if the questions themselves are solid. Weighting shapes reality. Overrepresenting certain ...

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 ...

Let us start with the biggest paradox. In all probability, you have never been interviewed for any of the opinion polls. How can the polls then claim to reflect ?public opinion?? The story goes that a ...

The National Sample Survey, under the Ministry of Statistics and Programme Implementation, has been conducting large-scale sample surveys on All-India basis since the 1950s. These surveys are the most ...