This book is very beneficial for the post graduate students, researchers, statisticians, social scientists and other persons working in the field of sampling. It is very common problem in practice to deal with the skewed data. The use of arithmetic mean to measure the central tendency may gives misleading conclusions in such cases. To deal with the skewed data the appropriate measures of central tendency are geometric and harmonic mean. In this book the estimators of population geometric and harmonic mean along with the arithmetic mean and variance have been given very beautifully under different sampling techniques.