I don't believe so.
But you can do a similar things with global variables.
Customize or create a new panes view, and add this to the Set rules for file display (using the Import/Export button):
[Media Type]=[Audio] [=1save(-1,v_[name]_[artist])]=1 [=1ifelse(isequal(load(v_[name]_[artist]), -1), save([Rating], v_[name]_[artist]), !isequal([Rating], load(v_[name]_[artist])), save(10,v_[name]_[artist]))]=1
Add an Artist and an Name column. Also add an expression column, call it Ratings, with the expression value of:
Load(v_[name]_[artist])
Once the view is done, select the 10 item under the Ratings column. All the tracks now show should be your mixed ratings.