Facebook's recently disclosed 2012 experiment in altering the tone of what its users saw in their newsfeeds has brought it plenty of negative opinions to chew on. Here's one, pointed out by an anonymous reader: Facebook's methodology raises serious ethical questions. The team may have bent research standards too far, possibly overstepping criteria enshrined in federal law and human rights declarations. "If you are exposing people to something that causes changes in psychological status, that's experimentation," says James Grimmelmann, a professor of technology and the law at the University of Maryland. "This is the kind of thing that would require informed consent." For a very different take on the Facebook experiment, consider this defense of it from Tal Yarkoni, who thinks the criticism it's drawn is "misplaced": Given that Facebook has over half a billion users, it’s a foregone conclusion that every tiny change Facebook makes to the news feed or any other part of its websites induces a change in millions of people’s emotions. Yet nobody seems to complain about this much–presumably because, when you put it this way, it seems kind of silly to suggest that a company whose business model is predicated on getting its users to use its product more would do anything other than try to manipulate its users into, you know, using its product more. ... [H]aranguing Facebook and other companies like it for publicly disclosing scientifically interesting results of experiments that it is already constantly conducting anyway–and that are directly responsible for many of the positive aspects of the user experience–is not likely to accomplish anything useful. If anything, it’ll only ensure that, going forward, all of Facebook’s societally relevant experimental research is done in the dark, where nobody outside the company can ever find out–or complain–about it."