How Good Are Robo-Graders?

stoolpigeon writes "With a large study showing software grades essays as well as humans, but much faster, it might seem that soon humans will be completely out of the loop when it comes to evaluating standardized tests. But Les Perelman, a writing teacher at MIT, has shown the limits of algorithms used for grading with an essay that got a top score from an automated system but contained no relevant information and many inaccuracies. Mr. Perelman outlined his approach for the NY Times after he was given a month to analyze E-Rater, one of the software packages that grades essays."