Concept

Sampling fraction

In sampling theory, the sampling fraction is the ratio of sample size to population size or, in the context of stratified sampling, the ratio of the sample size to the size of the stratum. The formula for the sampling fraction is where n is the sample size and N is the population size. A sampling fraction value close to 1 will occur if the sample size is relatively close to the population size. When sampling from a finite population without replacement, this may cause dependence between individual samples. To correct for this dependence when calculating the sample variance, a finite population correction (or finite population multiplier) of (N-n)/(N-1) may be used. If the sampling fraction is small, less than 0.05, then the sample variance is not appreciably affected by dependence, and the finite population correction may be ignored.

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https://en.wikipedia.org/wiki/Sampling_fraction

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Philipp Jürgen Schneider

Hubert Girault

Education: 1979 - Engineering diploma from Grenoble Institute of Technology. FRANCE. 1982 - PhD- Department of Chemistry, University of Southampton. Thesis entitled : Interfacial studies using drop image processing techniques. Positions : 1982 - 1984 SERC Research Fellow. University of Southampton. 1984 - 1985 CNRS Research Fellow. University of Southampton. 1985 - 1992 Lecturer in Physical Chemistry, University of Edinburgh. 1992 - Professor of Physical Chemistry, Ecole Polytechnique Fédérale de Lausanne. 2011 - 2014 Dean of Bachelor and Master studies Hubert Girault is the author of 2 textbooks, the co-author of about 600 scientific publications with more than 20'000 citations and the co-inventor of more than 15 patents. During his academic career, he has supervised 70 PhD students. 30 alumni of his laboratory are now Professors. Honours: Faraday medal 2006, Royal Society of Chemistry, Fellow of the International Society of Electrochemistry 2007, Reilley Award 2015. Fellow of the Electrochemical Society (USA), Shikata International medal, Polarography Society of Japan. Associate editor of Chemical Science

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