Evaluation should effectively assess the degree to which a learner has acquired the knowledge, skills and attitudes expected from the curriculum outcomes. Ideally, if the process of evaluation truly measures learning achievement, any instructor will award exactly the same grade as any other for a particular assignment. Of course, this is seldom true, and experience suggests that even in the best of circumstances, developing consistently fair methods of evaluation remains a difficult task for many instructors. Because instructors are most often the sole determining influence on the evaluation of students enrolled in their courses, the grades awarded will reflect the instructor's habitual methods of judgment. The research on evaluation shows that there is no consistent pattern in instructors' approach to this task.
Some teachers tend to expect more of their students than do others.
In sum, the accuracy and fairness of evaluation can be limited by inconsistency within and across classroom experience, by a lack of instructor objectivity, or by an inadvertent introduction of evaluation bias. Some education in what is good or bad about particular evaluative strategies is provided by teachers' own many years of experience as students undergoing evaluation. Often, that replication of traditional methods fails to address the issues which have lead to inequity in evaluation. In suggesting that equivalent products and standards should be required across multi-section classes, many respondents recognized the inherent subjectivity of grading and evaluation processes, and the persistence of bias in evaluation. A theoretical awareness of the evaluation bias problem must be accompanied by a practical understanding of its causes and through that understanding, by efforts to develop and maintain reliable and equitable evaluation methods.