Echantillonnage avec probabilités inégales et sans remise : comparaison de l'estimateur de Horvitz et Thompson à des alternatives plus simples

When sampling with unequal probabilities and without replacement, the inclusion probabilities of units in the sample which allow the use of HOROWITZ and THOMPSON's estimator of a total, are obtained by simulation. The biases encountered when analysing such a sample as if drawn with equal probabilities and without replacement, or with unequal probabilities but with replacement, are also studied. Finally, the interest of using sampling with unequal probabilities rather than simpler sampling methods is discussed.