This article analyses the crucial role of user data for digital markets contestability and presents policy proposals devised to address growing concerns about the dominance of data-rich incumbents in digital markets. To this end, we discuss a data-driven theory of harm that would warrant ex-ante data access regulation and highlight that niche entry and growth should be the primary economic policy objective in digital markets characterized by strong data-driven network effects. We then evaluate regulatory data access remedies with respect to the involved economic trade-offs and their effectiveness for promoting niche entry and growth. Firstly, we analyse remedies that would limit the collection of user data by data-rich incumbents such as data silos and line of business restrictions. Secondly, we consider remedies that facilitate sharing of (user) data by opening up access to raw behavioural user data collected by data-rich incumbents. In particular, we propose a dual approach with two complementary types of data access remedies: bulk sharing of broad anonymized raw user data and continuous, real-time data portability of deep raw data that contain personally identifiable information. Finally, we comment on the recent proposal for a Digital Markets Act by the European Commission with respect to our findings.

中文翻译：

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大数据和数字市场的可竞争性：损害理论和数据访问补救措施

本文分析了用户数据对数字市场竞争性的关键作用，并提出了旨在解决对数据丰富的现有企业在数字市场中的主导地位日益增长的担忧的政策建议。为此，我们讨论了一种数据驱动的危害理论，该理论将保证事前数据访问监管，并强调利基进入和增长应该是以强大的数据驱动网络效应为特征的数字市场的主要经济政策目标。然后，我们评估监管数据访问补救措施与所涉及的经济权衡及其促进利基进入和增长的有效性。首先，我们分析了限制数据丰富的现有企业收集用户数据的补救措施，例如数据孤岛和业务线限制。其次，我们考虑通过开放访问由数据丰富的现有企业收集的原始行为用户数据来促进（用户）数据共享的补救措施。特别是，我们提出了一种具有两种互补类型的数据访问补救措施的双重方法：广泛匿名原始用户数据的批量共享和包含个人身份信息的深度原始数据的连续实时数据可移植性。最后，我们就欧盟委员会最近针对我们的调查结果提出的数字市场法案提案发表评论。包含个人身份信息的深度原始数据的实时数据可移植性。最后，我们就欧盟委员会最近针对我们的调查结果提出的数字市场法案提案发表评论。包含个人身份信息的深度原始数据的实时数据可移植性。最后，我们就欧盟委员会最近针对我们的调查结果提出的数字市场法案提案发表评论。