Some Limit Theorems with Applications in Sampling Theory

Abstract

From a finite population units are drawn with varying probabilities with replacement. There is a certain cost for observing a unit. In this paper samples are obtained partly by drawing a fixed number of times, and partly by drawing and observing units until the cost reaches a specified level. Let $X_k$ be the number of times the $k$th unit has been drawn in either case. Consider for a given function $g(\bullet)$ the random variable $Z = \sum_k g(X_k, k)$. Under general conditions it is proved that $Z$ is asymptotically normally distributed (actually a multidimensional generalization is considered). By appropriate choices of $g(\bullet)$ asymptotic distributions are obtained in successive sampling with varying probabilities without replacement and for the mean of the distinct units in a simple random sample with replacement. It is also investigated how heterogeneous catchability and effects of marking affect the "Petersen" estimator in capture-recapture theory.