عنوان مقاله [English]
Circular data are typical examples of directional data with a specific regular period. Because the presence of outliers leads to invalid statistical inferences on the parameters of the circular regression models, their prevalence in analyzing these models requires particular attentions. There are different approaches for modeling the structure of the data set with outliers in which using the mixture models is among the most important ones. As a new idea, to study the methods in determining the outlier data and to employ the mixture model of Von Mises distribution are considered in this paper. The EM algorithm is utilized to estimate the parameters of these models. The performance of the proposed models is investigated using some simulation studies, and then the confusion matrix is considered to evaluate the accuracy of fitting models. Also, the proposed methods are applied to analyze a real data set, related to the wave directional analysis in the Bushehr province in Iran.