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

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 ...

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 ...

The method of simple random sampling (METHOD=SRS) selects units with equal probability and without replacement. Each possible sample of n different units out of N has the same probability of being ...