A robust statistic to detect single and multi-outliers in univariate circular data is proposed. The performance of the proposed statistic was tested by applying it to a simulation study and to three real data sets, and was demonstrated to be robust.
Mahmood, E. A., Rana, S., Midi, H., & Hussin, A. G. (2017). Detection of Outliers in Univariate Circular Data using Robust Circular Distance. Journal of Modern Applied Statistical Methods, 16(2), 418-438. doi: 10.22237/jmasm/1509495720