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 ...

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 ...

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Part One: The nature and process of social research ; Social research strategies ; Research designs ; Planning a research project and formulating research questions ; Getting started: Reviewing the ...

Sean Ross is a strategic adviser at 1031x.com, Investopedia contributor, and the founder and manager of Free Lances Ltd. Gordon Scott has been an active investor and technical analyst or 20+ years. He ...