Which is an effective method for calculating goodwill? A) Full Goodwill Method B) Proportionate Goodwill Method

Well, if you want to follow International Accounting standards & IFRS. I'd suggest Full goodwill method.

Reason being when you calculate partial goodwill you only account for the goodwill of the Controlling party.

If you calculate fullgoodwill it shows complete picture, taking account of goodwill share of minority as well as of controlling party , which makes more sense.

Proportionate good will method i suggested

I'll go wtih partial goodwill method, make more sense for me.