Researchers use information about the amount of time people spend on digital media for a variety of purposes including to understand impacts on physical and mental health as well as attention and learning. To measure time spent on digital media, participants' self-estimation is a common alternative method if the platform does not allow external access to directly measure people's time spent. However, prior work raises questions about the accuracy of self-reports of time spent on traditional social media platforms and questions about the cognitive factors underlying people's perceptions of the time they spend on social media. In this work, we build on this body of literature by exploring a novel social platform: TikTok. We conduct platform-independent measurements of people's self-reported and server-logged TikTok usage (n=255) to understand how users' demographics and platform engagement influence their perceptions of the time they spend on the platform and the accuracy of their estimates. Our work adds to the body of work seeking to understand time estimations in different digital contexts, and identifies new engagement factors that may be relevant in future social media time estimation studies.

翻译：研究者利用人们在数字媒体上花费的时间信息，用于多种目的，包括理解对身心健康、注意力及学习的影响。当平台不允许外部直接测量用户使用时间时，参与者自我评估是测量数字媒体使用时长的常用替代方法。然而，先前研究对传统社交媒体平台上自我报告时间使用的准确性提出了质疑，并探讨了人们感知自己在社交媒体上花费时间的认知因素。本研究在此基础上，探索了一个新型社交平台：TikTok。我们通过平台无关的测量方法，收集了参与者自我报告和服务器记录的TikTok使用数据（样本量n=255），以理解用户人口统计学特征及平台参与度如何影响他们对使用时间的感知以及估算的准确性。本研究丰富了理解不同数字情境下时间估算的相关文献，并识别出未来社交媒体时间估算研究中可能具有相关性的新型参与因素。