This paper discusses big technology and data privacy. First, we show the rapid rise in technology firms since the millennium. Using Facebook as a case study (the most popular social network in 2022), we show its reliance on personally identifiable data collection and advertising. Second, we investigate the Cambridge Analytica data breach. We show that stock prices fall in response to the data breach using event study methods. Cumulative abnormal returns decline by about 9.8% in the event window. Third, we discuss policy options in response to data privacy concerns. The GDPR provides a legislative model for protecting individually identifiable data.

中文翻译：

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大技术与数据隐私

本文讨论大技术和数据隐私。首先，我们展示了自千禧年以来科技公司的快速崛起。使用 Facebook 作为案例研究（2022 年最受欢迎的社交网络），我们展示了它对个人身份数据收集和广告的依赖。其次，我们调查了 Cambridge Analytica 数据泄露事件。我们使用事件研究方法表明，股价因数据泄露而下跌。累计异常收益在事件窗口内下降约 9.8%。第三，我们讨论了应对数据隐私问题的政策选择。GDPR 提供了一个保护个人身份数据的立法模型。