Jeff Hancock, a Stanford University professor who was involved in the study, analyzed the hate mail he got, and found four themes. Some asked, "How dare you manipulate my news feed?" although it was always generated by an algorithm of some sort. Others accused him of attempted mind control. Some complained that the news feed was important to them. And some asked if they were part of the experiment.
But the biggest problem, he added, was probably that Facebook violated their expectations. "They thought of it as a platform, and platforms don't experiment on people," he said.
Consent is not always required for such experiments -- especially when the users are exposed to minimal risks, added Hancock.
Elizabeth Churchill, Google's director of user experience, told the conference that designers should routinely design experiments to support their design decisions as part of the process of creating a user experience, using qualitative and quantitative measures that can work together to improve overall quality.
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