statistical sampling probability-proportional-to-size sampling Alejandra Gonzalez-Beltran PPS sampling Philippe Rocca-Serra Probability proportional to size ('PPS') sampling is a sampling method in which the selection probability for each element is set to be proportional to its size measure, up to a maximum of 1. In a simple PPS design, these selection probabilities can then be used as the basis for Poisson sampling. However, this has the drawback of variable sample size, and different portions of the population may still be over- or under-represented due to chance variation in selections. https://en.wikipedia.org/wiki/Sampling_(statistics)#Probability-proportional-to-size_sampling ready for release