2.4. New Partially Systematic Sampling (NPSS)
Leu and Tsui (1996) [8] developed the New Partially Systematic Sampling (NPSS) in order to derive an unbiased
estimator of the variance of systematic sampling V y( sy ) . The population size N need not be a multiple
of sample size n; therefore, it is a suitable procedure when N nk ≠ . The procedure entails selection of SRS of
size a and the remaining sample of size (n-a) systematically, these samples are combined to derive an unbiased
estimate of V y( sy ) . Thus, NPSS combines SRS with systematic sample to obtain its estimates thereby deviating
from the objective of this study as we intend to observe performances when systematic sampling is employed
as a choice scheme within strata and not when SRS is combined with systematic samples.