The difference between objective and subjective testing is between methods of evaluating a test. Scoring is objective when no judgement on the part of the scorer is needed. Test items can be evaluated objectively if there is only one right answer and scorers can mark a test by following an answer key. Objective tests can be constructed by means of multiple choice questions, true or false questions or matching. The advantage of an objective test is that test takers cannot create alternative, acceptable answers. When there is the need for judgement on the part of the scorer, then scoring is subjective. In that case, test takers might provide some acceptable, alternative responses that the teacher or test developer did not predict. There are different degrees of subjectivity in test scoring. For example, evaluating short answers is less subjective than evaluating a longer text.

http://www.carla.umn.edu/assessment/vac/evaluation/p_2.html. Retrieved January 8, 2012.
Hughes, A. (1989). Testing for Language Teachers. Cambridge: University Press.

Submitted by Olla Grosicka