The Quality of play index seems to be highly correlative with ELO rating, so to players, such as myself, who only play online it could provide some indication of what my ELO would look like.
Reference: http://chess-db.com/public/research/qualityofplay.html
This might be related/similar to the thread about CTORH (I couldn't find any reference to this system in google): http://en.lichess.org/forum/lichess-feedback/quality-rating-system-
Reference: http://chess-db.com/public/research/qualityofplay.html
This might be related/similar to the thread about CTORH (I couldn't find any reference to this system in google): http://en.lichess.org/forum/lichess-feedback/quality-rating-system-