b79ce3e4_arning___five_practical_guides__Some_possible_disadvantages
[Assessment option] Combination of Group Average and Individual Mark The group mark is awarded to each member with a mechanism for adjusting for individual contributions [Some possible advantages] perceived by many students as fairer than shared group mark [Some possible disadvantages] 
additional work for staff in setting up procedure for and in negotiating adjustments
Assessing Student Learning - five practical guides
Some possible disadvantages