Viral phenomenon refers to a special case of maximum market penetration at a rapid growth rate, within a short duration of time and at a low advertising cost. The shrinking product lifecycles and multitude of competing products emphasize the need for measurement of viral success. Current studies focus on a single measure and for only freely available online information. This paper develops a multimeasure viral phenomenon measurement methodology and empirically measures the robustness for tangible products (purchased with monetary value). The viral phenomenon factors of product performance and rate of growth are developed, taking four measures of virality, namely spikes, peak, magnitude, and exponential growth. Two products under the umbrella of Apple, namely iPod and iPad, are studied, using sales data and the related buzz created in social mediums like Twitter. The methodology successfully differentiates a genuine viral from a case of hype or popularity. New insights into iPod and iPad technology trajectory emerge as well.

中文翻译：

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探索有形购买产品的病毒现象方法：以 iPod 和 iPad 为例

病毒现象是指在短时间内以较低的广告成本实现快速增长的最大市场渗透率的特例。产品生命周期的缩短和众多竞争产品强调了衡量病毒成功的必要性。当前的研究侧重于单一措施，并且仅针对免费提供的在线信息。本文开发了一种多测量病毒现象测量方法，并根据经验测量有形产品（以货币价值购买）的稳健性。开发了产品性能和增长率的病毒现象因素，对病毒性采取四种措施，即峰值、峰值、幅度和指数增长。研究了苹果旗下的两款产品，即 iPod 和 iPad，使用销售数据和在 Twitter 等社交媒体中产生的相关嗡嗡声。该方法成功地将真正的病毒与炒作或流行情况区分开来。对 iPod 和 iPad 技术轨迹的新见解也出现了。