Suppose that the sample of students described in the previous section was actually selected using stratified random sampling. In stratified sampling, the study population is divided into ...

Mary Hall is a editor for Investopedia's Advisor Insights, in addition to being the editor of several books and doctoral papers. Mary received her bachelor's in English from Kent State University with ...

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 is shown that variance estimates for regression coefficients in exposure-stratified case-cohort studies (Borgan et al 9 Lifetime Data Anal., 6,2000,39-58) can easily be obtained from influence ...

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 ...