A general family of dual to ratio-cum-product estimator in sample   surveys
  This paper presents a family of dual to ratio-cum-product estimators for the finite population mean. Under simple random sampling without replacement (SRSWOR) scheme, expressions of the bias and mean-squared error (MSE) up to the first order of approximation are derived. We show that the proposed family is more efficient than usual unbiased estimator, ratio estimator, product estimator, Singh estimator (1967), Srivenkataramana (1980) and Bandyopadhyaya estimator (1980) and Singh et.al. (2005) estimator. An empirical study is carried out to illustrate the performance of the constructed estimator over others. 
Rajesh Singh, Mukesh Kumar, P. Chauhan, N. Sawan, S. Florentin
stat.ME