As was stated earlier, the pool of respondents is self-selecting and therefore disproportionately likely to be voted on by those who experienced terrible things.
Here's what I despise about this poll and those like it: it lends apparent legitimacy to the argument of those who downplay nearly all sexual assault allegations. By exaggerating the number of those who are assaulted, you minimize the impact and severity of those who truly are. If people think sexual assault figures are phony, they don't believe the people who deserve to be believed. Those conducting these polls and releasing these numbers thinks they're doing some great work, when in actuality they're doing great harm to true victims, of which there are plenty, at PSU and in every community.