Digital public health interventions at scale: The impact of social media advertising on beliefs and outcomes related to COVID vaccines.

Public health organizations increasingly use social media advertising campaigns in pursuit of public health goals. In this paper, we evaluate the impact of about $40 million of social media advertisements that were run and experimentally tested on Facebook and Instagram, aimed at increasing COVID-19 vaccination rates in the first year of the vaccine roll-out. The 819 randomized experiments in our sample were run by 174 different public health organizations and collectively reached 2.1 billion individuals in 15 languages. We find that these campaigns are, on average, effective at influencing self-reported beliefs-shifting opinions close to 1% at baseline with a cost per influenced person of about $3.41. Combining this result with an estimate of the relationship between survey outcomes and vaccination rates derived from observational data yields an estimated cost per additional vaccination of about $5.68. There is further evidence that campaigns are especially effective at influencing users' knowledge of how to get vaccines. Our results represent, to the best of our knowledge, the largest set of online public health interventions analyzed to date.

Attenuating the school context increases students’ academic self-concept

Big-Fish-Little-Pond (BFLP) theory posits that being surrounded by high-ability peers reduces students’ self-perceived ability – i.e., their academic self-concept (ASC), which is known to regulate the effort students put into education. We add to this literature the finding that the school context alone, without referring to peers’ ability, triggers social comparison and can decrease students’ ASC. We hypothesize that attenuating the school context increases students’ ASC. The paper shows two examples of how attenuating school context leads to an increase in ASC. In Study 1, we exploited COVID-19-induced home-based education where students learned online without their usual school context. We find that students’ ASC in reading and writing increased outside the school context. In the randomized survey experiment of Study 2, we treated students by asking first for their ASC and subsequently their grades – thus, we attenuated the school context by ordering the questions. We asked control students first about their grades and subsequently their ASC. We found that treated students’ ASC increased in reading (but not in writing) compared to the control students who first reported their grades and then their ASC. The results indicate that the school context alone renders the perception of ability relative to peers, which triggers an unintended negative effect on students’ ASC. © 2021, Oviedo University Press. All rights reserved.

Social punishment for breaching restrictions during the COVID-19 pandemic.

In response to the novel coronavirus outbreak, the Japanese government requested the temporary closure of businesses. Consequently, complying with restrictions came to be recognized as the social norm, and stores that continued with business as usual were seen as norm-breakers. This study empirically investigates costly punishment behavior for stores' violation of restrictions and how this behavior changes when a decision-maker receives information pertaining to contrasting norms, implicitly requiring the opposite response. By implementing joy-of-destruction minigames, we found that costly punishment behavior for norm-breakers was significantly stimulated (by approximately 11%) but not increased when additional information was provided.