  Recent studies using data on social media and stock markets have mainly
focused on predicting stock returns. Instead of predicting stock price
movements, we examine the relation between Facebook data and investors'
decision making in stock markets with a unique data on investors' transactions
on Nokia. We find that the decisions to buy versus sell are associated with
Facebook data especially for passive households and also for nonprofit
organizations. At the same time, it seems that more sophisticated
investors---financial and insurance institutions---are behaving independently
from Facebook activities.
