THE INTELLIGENT ESSAY ASSESSOR
A psychology professor at the University of Colorado at Boulder is
spearheading the creation of an Intelligent Essay Assessor, a computerized
tool to assist professors in grading students' written essays. Thomas
Landauer says that to use the program, a professor must first teach it to
recognize both good and bad essay writing by feeding it examples of both,
which have been manually graded. The program can also be trained using
what he calls a "gold standard" -- passages from textbooks or other
materials written by experts on the same subject as the essay to be
graded. While earlier digital essay graders work by analyzing essays
mechanically -- looking at sentence structures and counting commas,
periods and word lengths -- Landauer says his program can actually
"understand" the student's writing using sophisticated artificial
intelligence technology called "latent semantic analysis." It does so by
comparing the patterns of word usage in student essays with the usage
patterns it has learned from the initial samples, enabling the computer
"to a good approximation, to understand the meanings of words and passages
of text." If an essay appears to convey the same knowledge as those used
in the examples, the computer gives it a high score. The Intelligent
Essay Assessor is not meant to be used to grade essays in
English-composition or creative-writing assignments, where a student is
being graded more on writing skill than subject knowledge.
(Chronicle of Higher Education 4 Sep 98)
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John Milton
Hong Kong University of Science & Technology
lcjohn@usthk.ust.hk