All written exams (except for preliminary exams) will be set by two readers who will be selected by the graduate adviser. The examiners should make up the exam in consultation with each other. They should grade the exam independently. If there is a discrepancy of more than half a grade, and they cannot resolve this discrepancy after discussion between themselves, the graduate advisor will appoint a third reader. The graduate advisor will also review all the exams before they are given, to ensure that the difficulty of the exam is roughly in line with other such exams that have been given in recent years. Students may take the exams anonymously if they wish.