Equating speedy answers with copying, the team concluded that about 10 percent of the students copied more than half of their homework, about 40 percent copied 10 to 50 percent of their homework, and about half the students copied less than 10 percent of their homework. By the end of the semester, students who copied 50 percent or more homework earned almost two letter grades below students who didn't copy very much, the team found. Heavy copiers were also three times more likely to fail the course.
They also report that certain change in course formatting and self-reporting academic dishonesty survey has reduced copying by factor of 4.
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