I need to learn more about the e-rater used to judge GMAT essays. From Computers can now judge writing?:
The e-rater was developed in the 1990s by subjecting essays to a ‘natural language processing technology’ that identifies grammar, sentence structure and strength of vocabulary. The computer also is programmed to scan for the elements present in a well-supported essay, said Richard Swartz, an executive with Educational Testing Service, which developed e-rater.
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Much of the research used to refine the technology involved taking essays that had been graded by people and looking for signs the computer could use to come close to those human judgments. The GMAT Web site boasts that “e-rater and independent readers agree, on average, 87 percent to 94 percent of the time.”Swartz emphasized the modest goal of computerized scoring: to judge the structure and coherence of the writing, rather than the quality of the thoughts and originality of the prose. In college, he said, professors grade the development of ideas, while essay-rating computers “are better suited to judgment about more basic-level writing.”