At the end of every turn, a list is compiled of the most proficient spell casters.
Each magic skill that your character has acquired will add to you total, as will spells that you have learned. Magic skills you know at the basic level will get you a score equal to your skills points. At the advanced level, each combat skill add twice your skill points. Thrice for each expert skill, 4 times for master and 5 times at grandmaster. 1st level spells will get you 1 points, 2nd level spells 2 points, etc.
E.g. if you have the elemental magic skill at 4 skill points and the advanced level, and the sorcery skill at 2 skill points and the basic level, and you know the 1st level spells 'flames' and 'light', your total score will be: (4 x 2) + (2 x 1) + 1 + 1 = 12.