2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/95605This paper proposes a class of estimators for population correlation coefficient when information about the population mean and population variance of one of the variables is not available but information about these parameters of another variable (auxiliary) is available, in two phase sampling and analyzes its properties. Optimum estimator in the class is identified with its variance formula. The estimators of the class involve unknown constants whose optimum values depend on unknown population parameters.10 pages, 1 table. To appear in "Libertas Mathematica"General Mathematics92B28, 62P20text