The Maximum Likelihood Estimator (MLE) was used to estimate unknown parameters of the simple circular regression model. However, it is very sensitive to outliers in data set. A robust method to estimate model parameters is proposed.
Mahmood, E. A., Midi, H., & Hussin, A. G. (2019). The comparison between maximum weighted and trimmed likelihood estimator of the simple circular regression model. Journal of Modern Applied Statistical Methods, 18(2), eP2689. doi: 10.22237/jmasm/1604188920