Tianjin University of Finance and Economics, Southwest University of Finance and Economics, etc. Statistics is a method of systematically expounding statistical theory according to its own research object, which reflects the phenomena and processes of things in a centralized, comprehensive and comprehensive way. There is a great competition for statistics postgraduate entrance examination. Tianjin University of Finance and Economics, Southwestern University of Finance and Economics and other schools recruit many people, so there is less pressure for postgraduate entrance examination. The basic task of statistics is to infer the population from the sample, explore the relationship between the sample and the population with the method of probability theory, and reveal the inevitable regularity hidden in accidental phenomena, so as to make a more correct conclusion on the population.