Set Rating Determination?

69topps8

Someone has probably already answered this question in previous threads but how do you determine the set rating? It doesn't appear to be a simple multiplication of the average grade x completion percentage. Is this a simple task?

Penny

Here's how its calculated using this hypothetical small set of 3 cards:

Card Weight
Babe Ruth 8
Ty Cobb 7
Ted Williams 6 ........ Total weight of the entire set is 21

Let's say you have two of the three cards: Babe Ruth with grade 9 and Ty Cobb with grade 7.
Your weighted gpa would be:
9 x 8 (Ruth: grade 9 x weight 8) + 7 x 7 (Cobb: grade 7 x weight 7) / 15 (total weight of your set) = (72 + 49)/15 = 8.06
Your set ratubg would be (72 + 49) / 21 (Total weight of the entire set) = 5.76

Basically, the formula for set rating is the sum of each registered card's grade x each card's weight divided by the total weight of the entire composite set.

Hope this makes it clear.

Penny
Collectors Universe