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The characteristics estimated by quick response surveys are, in many cases, rare. Because of its ease of use the random group estimator is commonly employed. It is felt, from years of empirical experience, that for rare characteristics the random group variance estimator overestimates the variance especially when the relative standard error of the estimate is large. The result of limiting a characteristic to one or two groups is a p-value which is high in these random groups and zero in the remaining random groups. In order to determine if the random group variance estimator is overestimating the variance, we decided to compare the random group variance estimator with the standard stratified variance estimator. This paper reviews the research done to compare these two variance estimators.