Sample selection with probability proportional to size sampling using SAS and R software

ABSTRACT In simple random sampling every unit in the population has the equal chance of being included in the sample but if the sampling units vary in their size then simple random sampling does not take into account the importance of larger units in the population contradiction to this probability proportional to size sampling scheme gives more probability of inclusion to larger units as compared to the smaller units in the sample. Therefore, Probability proportional to size sampling gives more efficient estimator as compared to equal probability sampling scheme. In this article, my aim is to select a sample of units on the basis of its size by using SAS and R software.