At each time point, I have a multivariate distribution $x=[x_1,x_2,x_3]$. I don't have that many time points around 3-15. I would like to know whether the change of the distribution over the time is significant. I checked out the Mann-Kendall trend test but it only works for a single value at each time point.
Do you guys know some good test for this? For a univariate distribution is fine with me as well.