Pinning alone? A study of the role of social ties on pinterest

This paper seeks to answer the question of whether social ties are important on interest-driven social networks, by analysing 4-years of activities of 50,000 randomly sampled users on Pinterest, a social image discovery website. We find that a non-trivial number of users' images are copied or repinned from strangers instead of friends, suggesting that social-based information exploration is not important. However, social interactions and social repins are critical for user retention: users interacting with friends are more likely to return Pinterest soon. These results suggest that the real role of social ties on interest-driven social networks is to enable bonding of users rather than seeking information.