How social networking sites may discriminate against women. Using the photo-sharing site Instagram as a test case, researchers demonstrate how two common recommendation algorithms amplify a network effect known as homophily in which similar or like-minded people cluster together. They further show how algorithms turned loose on a network with homophily effectively make women less visible; they found that the women in their dataset, whose photos were slightly less likely to be 'liked' or commented on, became even less popular once recommendation algorithms were introduced. Source 3k.