Q-score based on weighted share of scrap of chars and q-score of chars

Dear QM experts,

I would like to know how the Quality score can be calculated with reference to the below options in the material master

1. Weighted from Quality score of characterisitcs

2. Weighted from share of scrap for characteristcs

Please let me know what are the important settings needs to be done for this or it would be helpful if you provide any good documents. I checked in help.sap.com and other posts in SCN but couldnt get the clue how we can calculate it

Regards,

J.Balakrishnan