If home field is worth 3.5 then OSU is 10.5 points better then Michigan State. I think I would take the points, but OSU did hand it to us last year.
http://www.freep.com/story/sports/college/2015/06/26/michigan-msu-football-betting-lines/29348357/
http://www.freep.com/story/sports/college/2015/06/26/michigan-msu-football-betting-lines/29348357/