摘要：This paper introduces an unequal probability sampling without replacement
scheme with inclusion probability proportional to size. This new
scheme possesses some desirable properties with regard to .i and .ij , and
provides a non-negative variance estimator of the Horvitz and Thompson estimator,
when the values of the auxiliary variable fulfill some restrictions. On
comparing the suggested scheme with some of the existing sampling schemes
in respect of efficiency and stability of the variance estimator empirically, it
has been observed that the performance of the scheme is satisfactory.
关键词：Joint Inclusion Probability, Unequal Probability Sampling.
