I am interested in assessing whether my angular data distribution is satisfactorily described by a von Mises distribution.
In scale data, one can potentially use a Kolmogorov-Smirnov test. However, with circular data, it is usual to use the Watson test. The Rayleigh, Watson or Rao Spacing tests are used if a uniform distribution on the circle is suspected.
Question: Why is a Kolmogorov-Smirnov test not appropriate?
Also, I notice differences when plotting Probability and Quantile plots in routine software packages, e.g., Mathematica etc. vs. dedicated software for circular data? How are PP and QQ plots distorted in the circular data setting?