Searching for outliers, I found lots of really interesting and useful information in answers to three questions here, FInding outliers in multiple dimensions, How to remove outliers from data and Filtering and Replacing outliers. Maybe there are more that I missed, I don't know.
However all these answers concern some (maybe very clever and useful, but) newly designed solutions.
What I want to know is this:
BoxWhiskerChart has an option to show outliers. This means Mathematica does have some built-in algorithms for outlier detection, which might be also customizable.
Does anybody know how to access this functionality? How to invoke the corresponding functions, and where are they documented?