I checked several dictionaries and googled and checked previous biased-related questions here including Is it "biased towards" or "biased against"?, Word for being biased "towards the other direction"?, What do you call a person who is regionally biased? (unrelated),
Moreover, subscription-only LDOCE says:
unfairly preferring one person or group over another:
Of course I'm biased, but I thought my daughter's paintings were the best.
racially biased attitudes.
biased against/towards/in favour of
news reporting that was heavily biased towards the government
more interested in a particular thing than in another: biased towards
The majority of infants are biased towards being social rather than being antisocial.
biase (v.): To give a bias or one-sided tendency or direction to; to incline to one side; to influence, affect (often unduly or unfairly).,
biased: Influenced; inclined in some direction; unduly or unfairly influenced; prejudiced.
But I still can't understand the meaning of the following sentence:
I appreciate that you took the time to contact me. You are great in my opinion! But then I am very biased in your favour!
Does the sentence imply that:
a. The person saying this, is somewhat being unrealistically nice at their own expression of the addressee being great (in a negative way); or
b. Do they mean that they're not great enough to be able to return the favor (in a positive way being keen on the addressee's greatness)?
I also notice that LDOCE uses "favour" rather than favor, which probably indicates that this usage is British only?