Computers Grade Essays Fast … But Not Always Well |
|
|
As schools look to cut costs, more are considering using computers to grade students' writing assignments and to provide writing help. The programs can assess large numbers of papers in seconds.
Imagine a school where every child gets instant, personalized writing help for a fraction of the cost of hiring a human teacher — and where a computer, not a person, grades a student's essays.
It's not so far-fetched. Some schools around the country are already using computer programs to help teach students to write.
There are two big arguments for automated essay scoring: lower expenses and better test grading. Using computers instead of humans would certainly be cheaper, but not everyone agrees on argument No. 2.
Les Perelman, director of the student writing program at MIT, is among the skeptics. Perelman recently tried out a computer essay grading program made by testing giant Educational Testing Service.
"Of the 12 errors noted in one essay, 11 were incorrect," Perelman says. "There were a few places where I intentionally put in some comma errors and it didn't notice them. In other words, it doesn't work very well."
Perelman says any student who can read can be taught to score very highly on a machine-graded test.
That's because software developers build the computer programs by feeding in thousands of student essays that have already been graded by humans.
Then, by identifying the elements of essays that human graders seem to like, the programs create a model used to grade new essays. If human graders give essays with long sentences high marks, for example, the programs will tend to do so, as well. If human graders like big words, the programs will also, say, "manifest a tantamount predilection for meretricious vocabulary."
So, Perelman says, it's possible for students to score an A on a computer-graded essay simply by combining all the elements of an essay that would be scored highly by a human grader.
Source: NPR
Read more: