The key term is “useful”. They produce some data, but it’s likely to be misleading, primarily because of self-selection bias. So, no, you can NOT conclude that “there’s a good bit of street harassment, and it’s fairly frequent” on the basis of putting up a survey on a web page and keeping it there for a month or two.
The key term is “useful”. They produce some data, but it’s likely to be misleading, primarily because of self-selection bias. So, no, you can NOT conclude that “there’s a good bit of street harassment, and it’s fairly frequent” on the basis of putting up a survey on a web page and keeping it there for a month or two.