The difference between this experiment and advertising or A/B testing is _intent_. With A/B testing and advertising, the publisher is attempting to sway user behaviour toward purchasing or some other goal which is usually obvious to the user.
With this experiment, Facebook are modifying the news feeds of their users specifically to affect their emotions, and then measure impact of that emotional change. The intention is to modify the feelings of users on the system, some negatively, some positively.
Intentional messing with human moods like this purely for experimentation is the reason why ethics committees exist at research organisations, and why informed consent is required from participants in experiments.
Informed consent in this case could have involved popping up a dialog to all users who were to be involved in the experiment, informing them that the presentation of information in Facebook would be changed in a way that might affect their emotions or mood. That is what you would expect of doctors and researchers when dealing with substances or activities that could adversely affects people's moods. We should expect no less from pervasive social networks like Facebook.
With this experiment, Facebook are modifying the news feeds of their users specifically to affect their emotions, and then measure impact of that emotional change. The intention is to modify the feelings of users on the system, some negatively, some positively.
Intentional messing with human moods like this purely for experimentation is the reason why ethics committees exist at research organisations, and why informed consent is required from participants in experiments.
Informed consent in this case could have involved popping up a dialog to all users who were to be involved in the experiment, informing them that the presentation of information in Facebook would be changed in a way that might affect their emotions or mood. That is what you would expect of doctors and researchers when dealing with substances or activities that could adversely affects people's moods. We should expect no less from pervasive social networks like Facebook.