  In this paper we have considered the problem of estimating the population
mean in systematic sampling using information on an auxiliary variable in
presence of non response. Some modified ratio, product and difference type
estimators in systematic sampling have been suggested and their properties are
studied. The expressions of mean squared errors (MSEs) up to the first order of
approximation are derived. An empirical study is carried out to judge the best
estimator out of the suggested estimators.
