Chain regression type estimators using additional auxiliary variable in two phase sampling in the presence of non response

Two chain regression type estimators for the population mean using double sampling scheme in the presence of non response have been proposed and their properties are studied. In the case of fixed cost, the optimum values for the size of preliminary sample (n') sub sample n(<n') and sub sampling fraction (K) for non respondent group have been obtained The empirical study shows that the proposed estimators are more efficient than the relevant estimators for specified sample sizes n and K as well as for the fixed cost.