“The research was done in collaboration with two US universities to gauge if ‘exposure to emotions led people to change their own posting behaviours’.”
“The test saw Facebook ‘manipulate’ news feeds to control which emotional expressions the users were exposed to.”
“The study found that users who had fewer negative stories in their news feed were less likely to write a negative post, and vice versa.”
If you are among happy people, do you also feel happy? I don’t know.
Besides, I think that ‘positive’ posts do not necessarily reflect positive emotions. Emotions are one of the last things that psychological studies can deal with scientifically.
You are quite right - as well you know - negative does not necessarily mean ‘sad’.
Negative news might be anything affecting a person’s mental well-being, such as stories about fraud, corruption, greed or a favourite actor’s wedding. All depends on the reader’s interpretation of negative.