(Headline from print edition:How a bogus child sex trafficking study fooled some of the most respected media outlets in the country)
Like with most New Times articles it is really long so I recommend going to the link but I'll post 4 paragraphs from the first page.
<snip>
After all, the numbers are all guesses.
The data are based merely on looking at photos on the Internet. There is no science.
Eric Grodsky, a sociologist at the University of Minnesota who teaches about proper research construction, says that the study is fundamentally flawed.
"The method's not clean," Grodsky says. "You couldn't get this kind of thing into a peer-reviewed journal. There are just too many unanswered questions about their methodology."
http://www.phoenixnewtimes.com/2011-03-24/news/women-s-funding-network-sex-trafficking-study-is-junk-science/ (Here is more on the prostitution during the Super Bowl story that you may have seen posted in this forum)
http://www.dallasobserver.com/2011-01-27/news/the-super-bowl-prostitute-myth-100-000-hookers-won-t-be-showing-up-in-dallas/