At the moment, Moodle provides a basic analysis of quiz results through the standard reports.
It also provides ways for the grades and responses to be downloaded, for further detailed analysis offline.
Thirdly, quiz reports are a type fo plugin, so people can try to implement more sophisticated analyses. However, this is not something we would want to maintain in Moodle core, until such a plugin had proved itself as an add-on.
Therefore I am closing this issue.