Systematic sampling is very convenient in many practical situations, but does not provide a satisfactory estimator of the variance of the sample mean except when additional assumptions are made. A ...

Many techniques in survey sampling depend on the possession of information about an auxiliary variable x, or a vector of auxiliary variables, available for the entire population. Regression estimates ...

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Adam Hayes, Ph.D., CFA, is a financial writer with 15+ years Wall Street experience as a derivatives trader. Besides his extensive derivative trading expertise, Adam is an expert in economics and ...