I have read in some places that Coursera needs to improve its Review system, because the stars of this course do not match reality.
Clearly, this course is not in the "standard coursera" of quality (if you have already taken some courses, you will understand). The evaluation system is by colleagues, but it does not work, the classes are very weak, you will probably find the material of the wikipedia more didactic and in-depth. Few exercises. In fact, I don't even know if it can be called "exercise", it seems more like something for you to get a grade and not learn something. It needs to be reviewed urgently, as Coursera is now paid.