The small effects of political advertising are small regardless of context, message, sender, or receiver: Evidence from 59 real-time randomized experiments
The small effects of political advertising are small regardless of context, message, sender, or receiver: Evidence from 59 real-time randomized experiments
复制标题
DOI：
10.1126/sciadv.abc4046
复制
发表时间：
2020-09-01
期刊：
影响因子：
13.6
通讯作者：
Vavreck, Lynn
中科院分区：
文献类型：
--
作者：
Coppock, Alexander;Hill, Seth J.;Vavreck, Lynn
社会科学的证据表明，说服性信息的平均效果很小。对这些小影响的一个常见解释是异质性：说服术可能只在特定情况下有效。为了评估异质性，我们每周使用2016年美国总统竞选广告在真实的时间内重复一次实验。我们对49个政治广告进行了59个独特的实验，共有34,000人参与。我们通过发送者（候选人或团体），接收者（主题党派），内容（攻击或促销）和背景（战场与非战场，初选与大选，早期与晚期）来调查异质效应。我们发现小的平均影响候选人的候选人资格和投票。然而，这些微小的影响并不能掩盖实质性的异质性，即使政治学理论表明我们应该发现这种异质性，在初选和大选期间，在战场州，对民主党人、共和党人和无党派人士来说，影响同样很小。具有大的抵消效应的异质结不是小的平均效应的来源。
Evidence across social science indicates that average effects of persuasive messages are small. One commonly offered explanation for these small effects is heterogeneity: Persuasion may only work well in specific circumstances. To evaluate heterogeneity, we repeated an experiment weekly in real time using 2016 U.S. presidential election campaign advertisements. We tested 49 political advertisements in 59 unique experiments on 34,000 people. We investigate heterogeneous effects by sender (candidates or groups), receiver (subject partisanship), content (attack or promotional), and context (battleground versus non-battleground, primary versus general election, and early versus late). We find small average effects on candidate favorability and vote. These small effects, however, do not mask substantial heterogeneity even where theory from political science suggests that we should find it. During the primary and general election, in battleground states, for Democrats, Republicans, and Independents, effects are similarly small. Heterogeneity with large offsetting effects is not the source of small average effects.