clear, definite, marked, obvious, significant, strong
blatant
slight
possible, potential
The data was checked for potential biases.

alleged
conservative, left-wing, liberal, right-wing
He claims that America's media has a liberal bias.

cultural, political, racial
class, gender
personal
inherent, systematic
media

have
The newspaper has a clear bias towards/toward the party.

demonstrate, display, exhibit, reveal, show
avoid, eliminate, minimize, prevent, reduce
address, correct, overcome
We have now tried to correct the bias in our original report.

be free from
The newspaper was free from political bias.

creep in, exist, occur
Bias often creeps in through the wording of questions.

result in sth
affect sb/sth
favour/favor sb

with bias, without bias
All material must be selected and presented without bias.

with a bias
a newspaper with a strong left-wing bias

bias against
a bias against women

bias in favour/favor of, bias towards/toward
a bias towards/toward small companies

Bias is used with these nouns as the object:
result