in recent years, and the university has taken a number of steps to address it. Thomas Conroy, a university spokesman, said Monday that because the A.A.U. report was the first of its kind for Yale it was impossible to know whether those measures had paid off. Senator Kirsten Gillibrand, Democrat of New

exual assault. The new study cautioned that only 19 percent of students responded to the survey, far below the rates of some previous studies. The A.A.U. survey found that even in the most serious assaults, those involving penetration, almost three-fourths of victims did not report the episode to anyo