A simple random sample is used to represent the entire data population. A stratified random sample divides the population into smaller groups based on shared characteristics.

As an estimator of the population mean, the sample mean based only on the distinct units possesses a remarkable invariance property. Under three forms of simple random sampling, viz. simple random ...

A statistically designed random sampling scheme, based on as few as 100 people, would give a very high probability of detecting if there are any COVID-19 cases and highlight at-risk hotspots.

In this paper we derive the exact covariance of some sample moments for 'simple random sampling with replacement' (SRSWR) of a finite population. An application of the results is given for estimating ...