Shown are the empirical cumulative distribution functions (ECDFs) of the observed angles between the two (estimated) objective gradients on the best known Pareto set approximations for all 92 functions of the bbob-biobj(-ext) functions (more precisely, we display 1 plus the cosine of the angles). Instead of investigating all known solutions in the best available Pareto set approximations, we only do this for every 100th point to keep the file sizes low. The numbers of actually investigated points is shown in the figures for the last of the investigated instance of that particular dimension, here instances 1-5.
Click on each plot to enlarge.
The plots are retrieved from the bbob-biobj-plots GitHub repository.