Generalized Multivariate Estimator for the Mean of Finite Populations
Poduri S.R.S. Rao, Govind S. Mudholkar · Journal of the American Statistical Association · 1967
Just as ratio estimators are often indicated when the variable y is positively correlated with an auxiliary variable x so product estimators are indicated when y is negatively correlated with x. The method of estimation suggested by Olkin [4] is extended to the case where some or all of the auxiliary variables are positively correlated and some or all are negatively correlated with y.