Literature Review: Notifications

手机社交app中的 Notifications

从计算机和计算机软件时代到如今智能移动手机、手机应用的广泛使用，notification 也随着 IT 技术的进步而被使用于多样的情景，例如新邮件通知、新闻通知、电话通知（phone calls）、日程和闹钟提醒（alerts）、手机应用内通知（in-app）等 (Chen et al., 2019; Fitz et al., 2019)。如今人们平均每天会收到约63条 notification，且这个数字正在快速增加 (Pielot et al., 2018)。在这个电子和移动的时代人们已离不开 notification。

我们主要关心 notification 在手机应用内的场景，主要有社交平台app (Yoon et al., 2014)、电商app (Chen et al., 2019; Kumar & Johari, 2015)、新闻媒体app (Gavilan et al., 2020) 等。同时，以往研究中涉及的此类通知主要可以分为3种：通信消息通知，例如微信、qq等通信软件中用户互相发送的消息；社交动态通知，例如 Facebook、Twitter 等社交平台上用户新发动态的通知；应用自身的通知，例如健康管理软件给用户发送的提醒建议。在这些 notification 之中，学者发现来自于通讯应用的消息、与人有关的事件更新消息被用户认为是更重要的，而其他来源的通知更不易为用户所接受 (Fischer et al., 2010; Shirazi et al., 2014; Visuri et al., 2019)。

而 notification 并非一个完美的设计，在给用户提供便利的提醒服务的同时，也有可能带来烦扰、压力、注意力不集中、甚至多动症（Hyperactivity Symptoms）等负面影响 (Kushlev et al., 2016)。大部分学者都认同，notification 给用户带来的影响是正面还是负面，主要取决于推送消息提醒的时机（timing）和消息提醒的内容（content）(Visuri et al., 2019; Mehrotra et al., 2015; Fischer et al., 2010)。

• 在推送时机方面，过多的提示会打断用户当前的任务、造成疲劳等情绪，但 Pielot & Rello (2017) 在实验中发现完全关闭通知功能后用户会担心错过重要信息而频繁查看手机。所以只有把握好 notification 的数量和频率，才能避免用户产生压力。Fitz et al. (2019) 发现将消息集中打包（batching）在一天中的固定时间发送给用户会有最好的结果。
• 消息通知本身的内容也与用户对 notification 的接受程度密切相关。若内容与用户的兴趣和需求不相关，用户则对这些消息的接受程度低，更容易触发负面情绪。在社交通信手机应用中，notification 中显示的消息发送者与用户的社交关系越亲密，用户也更倾向于点击这条消息，甚至用户自身对于消息来源应用、消息发送者的猜测也能对点击产生影响 (Chang et al., 2019; Shirazi, 2014)。而近年来通知中显示的内容也被设计得越来越生动（vivid）来吸引用户，Gavilan et al. (2020) 发现生动的通知文字和图像对点击率都有正面的影响，而图像只有在和文字体现同样的主题时，才有对点击率的调节作用。

于是从这些角度入手，学者为手机应用的设计者提供了多种思路，来尽量避免 notification 的负面影响，给用户以更好的使用体验，从而促进用户消费（时间、金钱等）。例如设计更美观、内容更相关的消息提示信息 (Chen et al., 2019)，也有学者以推送时机为启发设计智能算法对通知进行忽略、延迟等操作，在最合适的时机推送给用户 (Mehrotra et al., 2015)。而 Chen et al. (2019) 站在用户的角度，提出用户可以对日渐增多、引发烦恼的 notification 采取 disturbance handling、self-preservation 等应对策略。

References

Chen, J. V., Tran, A., & Nguyen, T. (2019). Understanding the discontinuance behavior of mobile shoppers as a consequence of technostress: An application of the stress-coping theory. Computers in Human Behavior, 95, 83-93.

Gavilan, D., Fernández-Lores, S., & Martinez-Navarro, G. (2020). Vividness of news push notifications and users’ response. Technological Forecasting and Social Change, 161, 120281.

Kumar, A., & Johari, S. (2015, December). Push notification as a business enhancement technique for e-commerce. In 2015 Third International Conference on Image Information Processing (ICIIP) (pp. 450-454). IEEE.

Yoon, S., Lee, S. S., Lee, J. M., & Lee, K. (2014). Understanding notification stress of smartphone messenger app. In CHI’14 Extended Abstracts on Human Factors in Computing Systems (pp. 1735-1740).

Kushlev, K., Proulx, J., & Dunn, E. W. (2016, May). “ Silence Your Phones” Smartphone Notifications Increase Inattention and Hyperactivity Symptoms. In Proceedings of the 2016 CHI conference on human factors in computing systems (pp. 1011-1020).

Fitz, N., Kushlev, K., Jagannathan, R., Lewis, T., Paliwal, D., & Ariely, D. (2019). Batching smartphone notifications can improve well-being. Computers in Human Behavior, 101, 84-94.

Chang, Y. J., Chung, Y. J., & Shih, Y. H. (2019, October). I Think It’s Her: Investigating Smartphone Users’ Speculation about Phone Notifications and Its Influence on Attendance. In Proceedings of the 21st International Conference on Human-Computer Interaction with Mobile Devices and Services (pp. 1-13).

Visuri, A., van Berkel, N., Okoshi, T., Goncalves, J., & Kostakos, V. (2019). Understanding smartphone notifications’ user interactions and content importance. International Journal of Human-Computer Studies, 128, 72-85.

Fischer, J. E., Yee, N., Bellotti, V., Good, N., Benford, S., & Greenhalgh, C. (2010, September). Effects of content and time of delivery on receptivity to mobile interruptions. In Proceedings of the 12th international conference on Human computer interaction with mobile devices and services (pp. 103-112).

Sahami Shirazi, A., Henze, N., Dingler, T., Pielot, M., Weber, D., & Schmidt, A. (2014, April). Large-scale assessment of mobile notifications. In Proceedings of the SIGCHI conference on Human factors in computing systems (pp. 3055-3064).

Pielot, M., Vradi, A., & Park, S. (2018, September). Dismissed! a detailed exploration of how mobile phone users handle push notifications. In Proceedings of the 20th International Conference on Human-Computer Interaction with Mobile Devices and Services (pp. 1-11).

Pielot, M., & Rello, L. (2017, September). Productive, anxious, lonely: 24 hours without push notifications. In Proceedings of the 19th International Conference on Human-Computer Interaction with Mobile Devices and Services (pp. 1-11).

Mehrotra, A., Musolesi, M., Hendley, R., & Pejovic, V. (2015, September). Designing content-driven intelligent notification mechanisms for mobile applications. In Proceedings of the 2015 ACM International Joint Conference on Pervasive and Ubiquitous Computing (pp. 813-824).