Learn how representative samples and random samples differ and why combining them minimizes sampling bias for accurate data.

Julie Young is an experienced financial writer and editor. She specializes in financial analysis in capital planning and investment management. Dr. JeFreda R. Brown is a financial consultant, ...

where is the true probability of observing the jth response level in the ith population. The product multinomial distribution is simply the product of two or more individual multinomial distributions ...

We consider semiparametric models for which solution of Horvitz-Thompson or inverse probability weighted (IPW) likelihood equations with two-phase stratified samples leads to $\sqrt N $ consistent and ...

In sample surveys estimates are often required for subclasses of the population. The usual results assume that the domain numbers, M i, are either known exactly or completely unknown. The case where ...

It’s a truism that even large samples can be misleading if they are biased or, as market and social researchers say, if they are not representative for the universe. Therefore, it is essential whether ...