von Mises分布是圆形统计学或方向数据统计学中最重要的分布。本文简要地讨论了该分布的分布函数、参数估计、假设检验及其在确定医学正常值范围中的应用。本文(1)编制了不同正常值范围的长度表,以利应用;(2)举例说明如何较精确地拟合 vonMises 分布;(3)是《中国医学百科全书·医学统计学》中“圆形分布法”的补充. The von Mises distribution is the most important distribution in either round statistics or directional data statistics. This article briefly discusses the distribution function, parameter estimation, hypothesis testing and its application in determining the normal range of medicine. This article (1) compiles length tables with different ranges of normal value for application; (2) illustrates how to fit von Mises distribution more accurately; (3) is a circle in Chinese Medical Encyclopedia·Medical Statistics. “Distribution method” added.