$$Z_{j}={\lambda}Y_{j}+(1-{\lambda})Z_{j-1},\quad for\,j= 1,2,3,...,n.$$ The variance of mean using stratified sample is given as. $$S_{{yst}}^{2}=\sum\nolimits_{{h=1 ...

Surveys can provide valuable data about the prevalence of various conditions, behaviours and traits in a population, but there needs to be careful consideration of the methods used to sample the ...

The data in this report are based on two independent survey administrations with the same randomly selected, nationally representative group of respondents. The first is the center’s largest survey on ...

Suggested Citation: "2 Current Challenges and Opportunities in Federal Statistics." National Academies of Sciences, Engineering, and Medicine. 2017. Innovations in ...

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 ...