Referred workers are more likely than nonreferred workers to be hired, all else equal. In three field experiments in an online labor market, we examine why. We find that referrals contain positive information about worker performance and persistence that is not contained in workers’ observable characteristics. We also find that referrals perform particularly well when working directly with their referrers. However, we do not find evidence that referrals exert more effort because they believe their performance will affect their relationship with their referrer or their referrer’s position at the firm.

We exploit the randomness of weather and the relationship between weather and moviegoing to quantify social spillovers in movie consumption. Instrumenting for early viewership with plausibly exogenous weather shocks captured in LASSO-chosen instruments, we find that shocks to opening weekend viewership are doubled over the following five weekends. Our estimated momentum arises almost exclusively at the local level, and we find no evidence that it varies with either ex post movie quality or the precision of ex ante information about movie quality, suggesting that the observed momentum is driven in part by a preference for shared experience, and not only by social learning.