To inform product release and distribution strategies, research has analyzed cross-market spillovers in new product adoption. However, models that examine these effects for digital and viral media are still evolving. Given resistance to advertising, firms often seek to promote their own viral content to boost brand awareness. However, a key shortcoming of virality is its ephemeral nature. To gain insight into sustaining virality, we develop a quasi-experimental approach that estimates the backward spillover onto a focal platform by introducing a piece of content onto a new platform. We posit that introducing content to the audience of a new platform can generate word of mouth, which may affect its consumption within an earlier platform. We estimate these spillovers using data on 381 viral videos on 26 platforms (e.g., YouTube, Vimeo) and observe how consumption of videos on an initial “lead” platform is affected by their subsequent introduction onto “lag” platforms. This spillover is estimated as follows: for each multiplatform video, we compare its view growth after being introduced onto a new platform to that of a synthetic control based on similar single-platform videos. Analysis of 275 such spillover scenarios reveals that introducing a video onto a lag platform roughly doubles its subsequent view growth in the lead platform. This positive cross-platform spillover is persistent, bursty, and strongest in the first 42 days. We find that spillover is boosted when the video is consumed more in the lag platform, when the consumption rate peaks earlier in the lag platform, and when the lag platform targets a foreign market. Delaying a video’s introduction onto a lag platform affects spillover concavely, whereas its introduction onto additional platforms shows diminishing returns. We find further support for positive spillover through a small-scale randomized field experiment. Implications are discussed for platforms, content creators, and policy makers.

中文翻译：

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跨平台溢出在病毒含量消耗中的作用：使用合成控件的拟实验分析

为了提供产品发布和分销策略的信息，研究分析了新产品采用过程中的跨市场溢出效应。但是，检验这些对数字媒体和病毒媒体影响的模型仍在发展。鉴于对广告的抵制，公司经常寻求推广自己的病毒内容以提高品牌知名度。但是，病毒性的一个主要缺点是它的短暂性。为了深入了解维持病毒性，我们开发了一种准实验方法，该方法通过将内容引入新平台来估计向后溢出到焦点平台上。我们认为，向新平台的受众介绍内容可能会产生口碑，这可能会影响其在较早平台中的消费。我们使用26个平台（例如YouTube，Vimeo），并观察最初的“领先”平台上视频的消费如何受到随后引入“落后”平台的影响。这种溢出估计如下：对于每个多平台视频，我们将其引入新平台后的视图增长与基于类似单平台视频的综合控件的视图增长进行比较。对275种此类溢出情景的分析表明，将视频引入滞后平台大约会使领先平台中其随后的视图增长量增加一倍。这种积极的跨平台溢出在前42天内是持久的，突发的，并且最强。我们发现，当视频在滞后平台中消费更多，消费率在滞后平台中更早达到峰值以及滞后平台瞄准国外市场时，溢出效应会得到增强。延迟将视频引入延迟平台会影响到溢出效果，而将视频引入其他平台则表明收益递减。通过小规模的随机现场实验，我们发现了对正溢出的进一步支持。讨论了对平台，内容创建者和政策制定者的影响。