Working Paper: NBER ID: w25589
Authors: Vivi Alatas; Arun G. Chandrasekhar; Markus Mobius; Benjamin A. Olken; Cindy Paladines
Abstract: Celebrity endorsements are often sought to influence public opinion. We ask whether celebrity endorsement per se has an effect beyond the fact that their statements are seen by many, and whether on net their statements actually lead people to change their beliefs. To do so, we conducted a nationwide Twitter experiment in Indonesia with 46 high-profile celebrities and organizations, with a total of 7.8 million followers, who agreed to let us randomly tweet or retweet content promoting immunization from their accounts. Our design exploits the structure of what information is passed on along a retweet chain on Twitter to parse reach versus endorsement effects. Endorsements matter: tweets that users can identify as being originated by a celebrity are far more likely to be liked or retweeted by users than similar tweets seen by the same users but without the celebrities' imprimatur. By contrast, explicitly citing sources in the tweets actually reduces diffusion. By randomizing which celebrities tweeted when, we find suggestive evidence that overall exposure to the campaign may influence beliefs about vaccination and knowledge of immunization-seeking behavior by one's network. Taken together, the findings suggest an important role for celebrity endorsement.
Keywords: Celebrity Endorsement; Vaccination; Social Media; Public Health; Indonesia
JEL Codes: D85; I15; O33
Edges that are evidenced by causal inference methods are in orange, and the rest are in light blue.
| Cause | Effect |
|---|---|
| Celebrity tweets (Y60) | Increase in likes and retweets (O00) |
| Source attached to tweet (Y60) | Decrease in retweet rate (C22) |
| Exposure to campaign (K16) | Increase in recognition of campaign's hashtag (O36) |
| Exposure to campaign (K16) | Increase in awareness of immunization discussions (I19) |
| One standard deviation increase in exposure to campaign (D79) | Increase in knowledge about domestic vaccine production (L65) |
| One standard deviation increase in exposure to campaign (D79) | Increase in knowledge of neighbors' immunization behaviors (I14) |
| Exposure to campaign (K16) | Influence on offline knowledge and discussions about immunization (O36) |
| Celebrity endorsements (M37) | Influence on public health beliefs and behaviors (I14) |