A Bimodal Distribution on the Sphere
提出一种球面数据的双峰分布模型，数据大致等比例集中在两个方向，计算方便，且Fisher分布是其特例。
SUMMARY A distribution is proposed as a model for spherical data concentrated about two directions in roughly equal proportions. This distribution, which has convenient computational properties, includes the Fisher distribution as a special case (that in which the modal directions coincide).