The overall reflection of human thinking on the nature of objective things. Each discipline has its own basic category. Such as contradiction in philosophy, quality and quantity, essence and phenomenon, commodity value, abstract labor, concrete labor, chemical combination and decomposition in political economy, etc. Quartile is to divide all data into four equal parts, each of which contains 25% data, and the value of each point is quartile. As a form of quantile, quartile plays a very important role in statistics. Quantile is the variable value of each equal position after all the data of the population are arranged in order of size. If all the data are divided into two equal parts, it is the median; If it is divided into four equal parts, it is a quartile; The eighth division is the eighth division. Quartile, also called quartile, divides all data into four equal parts, each part contains 25% data, and the value of each point is quartile.