The Welfare Effects of Social MediaHunt Allcott, Luca Braghieri, Sarah Eichmeyer, and Matthew Gentzkow*January 27, 2019AbstractThe rise of social media has provoked both optimism about potential societal benefits andconcern about harms such as addiction, depression, and political polarization. We present arandomized evaluation of the welfare effects of Facebook, focusing on US users in the run-up to the 2018 midterm election. We measured the willingness-to-accept of 2,844 Facebookusers to deactivate their Facebook accounts for four weeks, then randomly assigned a subsetto actually do so in a way that we verified. Using a suite of outcomes from both surveys anddirect measurement, we show that Facebook deactivation (i) reduced online activity, includingother social media, while increasing offline activities such as watching TV alone and socializingwith family and friends; (ii) reduced both factual news knowledge and political polarization;(iii) increased subjective well-being; and (iv) caused a large persistent reduction in Facebookuse after the experiment. We use participants’ pre-experiment and post-experiment Facebookvaluations to quantify the extent to which factors such as projection bias might cause peopleto overvalue Facebook, finding that the magnitude of any such biases is likely minor relative tothe large consumer surplus that Facebook generates.JEL Codes: D12, D90, I31, L86, O33.Keywords: Social media, political polarization, subjective well-being, consumer surplus,projection bias.———————————————————————————*Allcott: New York University, NBER, and JPAL. hunt.allcott@nyu.edu. Braghieri: Stanford University. lu-cabrag@stanford.edu. Eichmeyer: Stanford University. saraeich@stanford.edu. Gentzkow: Stanford University andNBER. gentzkow@stanford.edu. We thank Nancy Baym, Moira Burke, Annie Franco, Alex Leavitt, and Todd Rogersfor helpful comments. We thank Kelly B. Wagman and Raj Bhargava for exceptional research assistance. We aregrateful to the Sloan Foundation for grant funding. The study was approved by Institutional Review Boards atStanford (eProtocol #45403) and NYU (IRB-FY2018-2139). This RCT was registered in the American EconomicAssociation Registry for randomized control trials under trial number AEARCTR-0003409. Survey instruments areavailable from https://sites.google.com/site/allcott/research. Disclosures: Allcott is a paid employee of Microsoft Re-search. Gentzkow does paid consulting work for Amazon and is a member of the Toulouse Network for InformationTechnology, a research group funded by Microsoft. Braghieri and Eichmeyer have no relevant or material disclosures.1每日免费阅读行业报告1、每日星球内分享10+精品报告；2、不定时分享国际投行报告，脱水研报等；3、行业报告均为公开内容，版权归原作者所有，星球仅分享内部学习。扫描右侧二维码即刻加入【行业报告（免费） 】星球（此页只为更多需要行业报告的朋友提供便利，希望不会影响您的阅读，谢谢理解！）1IntroductionSocial media have had profound impacts on the modern world. Facebook, which remains by farthe largest social media company, has 2.3 billion monthly active users worldwide (Facebook 2018).As of 2016, the average user was spending 50 minutes per day on Facebook and its sister platformsInstagram and Messenger (Facebook 2016). There may be no technology since television that hasso dramatically reshaped the way people communicate, get information, and spend their time.Speculation about social media’s welfare impact has followed a familiar trajectory, with earlyoptimism about potential benefits giving way to widespread concern about possible harms. At abasic level, social media dramatically reduce the cost of connecting, communicating, and sharinginformation with others.Given that interpersonal connections are among the most importantdrivers of happiness and well-being (Myers 2000; Reis, Collins, and Berscheid 2000; Argyle 2001;Chopik 2017), this could be expected to bring widespread improvements to individual welfare.Many have also pointed to wider social benefits, from facilitating protest and resistance in autocraticcountries, to encouraging activism and political participation in established democracies (Howardet al. 2011; Kirkpatrick 2011).More recent discussion has focused on an array of possible negative impacts. At the individuallevel, many have pointed to negative correlations between intensive social media use and bothsubjective well-being and mental health.1 Adverse outcomes such as suicide and depression appearto have risen sharply over the same period that the use of smartphones and social media hasexpanded.2 Alter (2018) and Newport (2019), along with other academics and prominent SiliconValley executives in the “time well-spent” movement, argue that digital media devices and socialmedia apps are harmful and addictive. At the broader social level, concern has focused particularlyon a range of negative political externalities. Social media may create ideological “echo chambers”among like-minded friend groups, thereby increasing political polarization (Sunstein 2001, 2017;Settle 2018). Furthermore, social media are the primary channel through which fake news andother ty...
发表评论取消回复