Starting from January 2010, the iBT writing scoring system will undergo significant changes. Research by ETS has found that the correlation between one human examiner and one computer-based scoring system (e-Rater) is better than that of two human examiners. Therefore, the scoring method will change from the original system where two examiners scored each of the two essays, with the raw score being the arithmetic average of the four scores, to a new system where one examiner and one computer scoring system (e-Rater) score each of the two essays, with the raw score being the arithmetic average of the two human and two e-Rater scores.