Abstract: Why do social media users spend so much time consuming content that seemingly harms them? We build a simple model to argue that advertising-driven platforms can find it profitable to display content that harms users when it is complementary to their time spent on the platform. These incentives disappear, absent network effects, in the case of a subscription-based business model because harmful content reduces the willingness to pay for the platform. Our results warn against interpreting increases in engagement on social media as welfare increases.

Abstract: Blind adoption of opinions put forward by political parties and influential figures can sometimes be harmful. Focusing on cases where the partisan gap in policy support has not yet arisen, we investigate whether its formation can be prevented by encouraging prior active engagement with non-partisan information. To address this question, we recruited N=851 Republicans for a study about net neutrality, an issue largely unfamiliar to the electorate, which refers to equal treatment of all internet traffic. In a pre-registered experiment, we randomly changed the order in which the following two types of information were provided: (i) partisan, underscoring Republicans’ opposition and Democrats’ support, and (ii) non-partisan, where the participants evaluated factual arguments about the pros and cons of the policy. Despite holding total information constant, we find that those who saw the non-partisan block first donated 46% more to a charity advocating for net neutrality (p=0.001). The treatment effect persisted in an obfuscated follow-up study, conducted several weeks after the intervention. However, we do not find an effect on donations when repeating the main study with a sample of Democrats.

Abstract: We exploit Facebook’s introduction of a filter hiding ads from the feed as a unique opportunity to study the effects of online ads on political behavior. In a pre-registered experiment, we randomly assigned participants to hide political ads (treatment) or alcohol ads (control) for several weeks preceding the 2020 US elections. We report an insignificant intent-to-treat effect of political ads on turnout (2.3 pp.), but we cannot rule out a sizable positive effect, with 95% confidence interval of [-2.8,7.4]. The result may mask important heterogeneity, with political ads making Democrats slightly more motivated to vote and Republicans – substantially less. We explore the reasons for this effect, such as natural variation in ad content: the majority of Facebook ads on users’ feeds skewed Democratic. Lastly, the effect on measures of affective polarization and informedness was negligible.

Abstract: Most social media users have encountered harassment online, but there is scarce evidence of how this type of toxic content impacts engagement. In a pre-registered browser extension field experiment, we randomly hid toxic content for six weeks on Facebook, Twitter, and YouTube. Lowering exposure to toxicity reduced advertising impressions, time spent, and other measures of engagement, and reduced the toxicity of user-generated content. A survey experiment provides evidence that toxicity triggers curiosity and that engagement and welfare are not necessarily aligned. Taken together, our results suggest that platforms face a trade-off between curbing toxicity and increasing engagement.

Abstract: Rising political polarization heightens concerns about politicization of regulatory agencies, prompting a reassessment of the trade-off between accountability and independence. Perceived out-group partisan oversight can erode trust in regulation and impact key markets like food and medicine—a dynamic we investigate empirically. First, we demonstrate the salience of the president-regulatory agency link in US media using TV transcript data. Second, in a pre-registered field experiment with 5,566 individuals, we test the channel using a case where both the Trump and Biden EPAs endorsed antibiotic spraying on citrus crops. This enabled us to randomize the partisanship of the administration, holding the scientific arguments constant. Out-group administration reduces support for spraying by 26%, lowers trust in the EPA’s evaluation, and raises donations to an opposing NGO by 15%. We find no effect on willingness to pay for citrus products on average, measured in an obfuscated follow-up. However, we document significant differences in effects for habitual and occasional consumers. Taken together, there is a cost to increasing executive dependence of agencies—it reduces out-party supporters’ trust and influences economic behavior, though distrust may not lower demand.

Abstract: Despite being often discussed both in practice and academic circles, the sunk cost effect remains empirically elusive. Our model based on reference point dependence suggests that the traditional way of testing it—by assigning discounts—may not produce the desired effect. Motivated by this, we evaluate it across the gain-loss divide in two pre-registered experiments. In an online study, we randomize the price (low, medium, or high) of a ticket to enter a real-effort task and observe its effect on play time. Despite varying the sunk cost by $2 for a 14-minute task and the sample size of N=1,806, we detect only a small effect (0.09 SD or 1.1 minutes). We further explore the economic applications of the effect in a field experiment on YouTube with N=11,328 videos in which we randomize whether the time until a pre-video ad becomes skippable is shortened (0 s), default (5 s), or extended (10 s). The intervention has an overall insignificant effect on video engagement. This is driven by a sizable negative effect on the extensive margin, a channel which is not present in the online study. Specifically, more users leave before the video starts in the extended treatment (5.2 pp. or 28% more relative to the shortened treatment). Taking the results of both studies together, we offer a cautionary tale that applying even the most intuitive behavioral effects in policy settings can prove challenging.