Apart from its ordinary significance this term is used in the following special sense. The coefficients of a linear function of the values of the sample units used to estimate population, stratum, or higher stage unit totals are called raising, multiplying, weighting or inflation factors of the corresponding sample units. If the raising factors of all the sample units are equal, the common raising factor is called the raising factor of the sample, and the sample itself is called self-weighting. It should be noted that the raising factors depend not only on the sampling plan but also on the method of estimation.