A predictive validity approach has been employed to find some implications to support evidences for Automated Essay Scoring (AES) systems. First, using R² values from multiple linear regression models, validity indices are compared first between multiple choice scores and essay scores across four AES systems. Secondly, R² values from models using only essay scores, the validity indices of four AES systems are hypothetically compared to see if how well AES systems could predict student outcome such as GPA.