Wikipedia, the Web's largest encyclopedia, frequently faces content disputes or malicious users seeking to subvert its integrity. Administrators can mitigate such disruptions by enforcing "page protection" that selectively limits contributions to specific articles to help prevent the degradation of content. However, this practice contradicts one of Wikipedia's fundamental principles$-$that it is open to all contributors$-$and may hinder further improvement of the encyclopedia. In this paper, we examine the effect of page protection on article quality to better understand whether and when page protections are warranted. Using decade-long data on page protections from the English Wikipedia, we conduct a quasi-experimental study analyzing pages that received "requests for page protection"$-$written appeals submitted by Wikipedia editors to administrators to impose page protections. We match pages that indeed received page protection with similar pages that did not and quantify the causal effect of the interventions on a well-established measure of article quality. Our findings indicate that the effect of page protection on article quality depends on the characteristics of the page prior to the intervention: high-quality articles are affected positively as opposed to low-quality articles that are impacted negatively. Subsequent analysis suggests that high-quality articles degrade when left unprotected, whereas low-quality articles improve. Overall, with our study, we outline page protections on Wikipedia and inform best practices on whether and when to protect an article.

翻译：维基百科作为全球最大的网络百科全书，经常面临内容争议或试图破坏其完整性的恶意用户。管理员可通过实施"页面保护"来减轻此类干扰，即选择性限制对特定文章的编辑权限，从而防止内容质量下降。然而，这一实践与维基百科"对所有贡献者开放"的基本原则相悖，且可能阻碍百科的持续完善。本文通过分析页面保护对文章质量的影响，旨在更深入理解页面保护是否及何时具有必要性。我们基于英语维基百科长达十年的页面保护数据开展准实验研究，聚焦于"页面保护请求"（即维基百科编辑者向管理员提交的书面请愿）所涉及的页面。通过匹配实际受保护页面与未受保护的相似页面，我们量化了干预措施对既定文章质量指标的因果效应。研究结果表明，页面保护的效果取决于干预前页面的初始特征：高质量文章呈现正面影响，而低质量文章则受到负面冲击。进一步分析显示，未受保护的高质量文章会出现质量退化，与之相反，低质量文章反而有所改善。总体而言，本研究梳理了维基百科的页面保护机制，并为是否及何时需要实施页面保护提供了最佳实践建议。