Good Vibrations: Can a Digital Nudge Reduce Digital Overload? Fabian Okekey, Michael SobolevyΦ, Nicola DellyΨ, Deborah Estriny yCornell Tech, ΦTechnion, Ψe Jacobs Institute [fno2;ms3377;nixdell;de226]@cornell.edu ABSTRACT Snapchat, and more, have become an integral part of people’s ev- Digital overuse on mobile devices is a growing problem in every- eryday lives, helping them to share their thoughts, connect with day life. is paper describes a generalizable mobile intervention friends and families, receive news updates, and enjoy many forms that combines nudge theory and negative reinforcement to create of digital entertainment. However, research has shown that tech- a subtle, repeating phone vibration that nudges a user to reduce nology burdens people with the pressure of continual availability their digital consumption. For example, if a user has a daily Face- [2, 37], the need to constantly check in [38, 47], and the ease to book limit of 30 minutes but opens Facebook past this limit, the procrastinate on work, studies, and personal goals [22, 39, 52]. As user’s phone will issue gentle vibrations every ve seconds, but the a result, many people desire to reduce or limit their technology vibration stops once the user navigates away from Facebook. We use [21]. A number of studies have suggested completely abandon- evaluated the intervention through a three-week controlled experi- ing social media [3], using feature phones instead of smartphones ment with 50 participants on Amazon’s Mechanical Turk platform [31], calling users daily to reect on their social media habits [6], with ndings that show daily digital consumption was successfully limiting usage through personal productivity tools [16, 25], and reduced by over 20%. Although the reduction did not persist aer commiing as a group to reduce digital distraction [29]. Many of the intervention was removed, insights from qualitative feedback these existing solutions combine a variety of dierent interventions suggest that the intervention made participants more aware of their at the same time, making if dicult to understand the eects of app usage habits; and we discuss design implications of episodically particular behavioral theories or techniques. applying our intervention in specic everyday contexts such as ed- e goal of our research is to design, implement, and evaluate a ucation, sleep, and work. Taken together, our ndings advance the generalizable technique that reduces digital consumption on mo- HCI community’s understanding of how to curb digital overload. bile devices. Specically, we created a mobile app intervention that uses nudge theory [53] from behavioral economics and negative CCS CONCEPTS reinforcement [20, 51] from behavioral psychology. A nudge refers to an intervention that steers people in a particular direction with- •Human-centered computing ! Ubiquitous and mobile comput- out eliminating their freedom of making the nal choice; while ing design and evaluation methods; negative reinforcement refers to the strengthening of a behavior by KEYWORDS avoiding a negative outcome or aversive stimulus. We combined these two concepts to design our digital intervention as a subtle, Digital Overload; Social Media; Vibration; Intervention; Digital repeating phone vibration that nudges a user to stop using a target Nudge; Negative Reinforcement; Smartphones mobile application whenever they exceed a daily usage limit. ACM Reference format: We evaluated our intervention through a controlled experiment Fabian Okekey, Michael SobolevyΦ, Nicola DellyΨ, Deborah Estriny. 2018. with 50 workers recruited on Amazon’s Mechanical Turk (MTurk) Good Vibrations: Can a Digital Nudge Reduce Digital Overload?. In Proceed- platform. Participants were randomly assigned to one of three ings of MobileHCI ’18: 20th International Conference on Human-Computer experimental conditions: control, rigid and personalized, and each Interaction with Mobile Devices and Services, Barcelona, Spain, September 3–6, group used the intervention for three weeks. Although we de- 2018 (MobileHCI ’18), 11 pages. signed our intervention to work on any target mobile application, DOI: 10.1145/3229434.3229463 we conducted our evaluation only on participants’ Facebook usage in order to avoid experiment confounds. In the control condition, 1 INTRODUCTION no intervention was applied; in the rigid condition, the daily Face- e amount of time that people spend consuming digital content book usage limit was pre-determined and remained static over the has dramatically increased over the years because of the opportu- study period; while in the personalized condition, a daily Facebook nity to use mobile devices in nearly every context and at nearly usage limit was calculated based on each participant’s usage habits. every moment. Popular mobile apps such as Facebook, YouTube, During the rst week of the experiment we did not deliver any ex- plicit interventions in order to measure each participant’s baseline Permission to make digital or hard copies of all or part of this work for personal or usage. In the second week, participants in the rigid and personal- classroom use is granted without fee provided that copies are not made or distributed for prot or commercial advantage and that copies bear this notice and the full citation ized conditions experienced the intervention whenever they used on the rst page. Copyrights for components of this work owned by others than ACM Facebook past their daily limit. In the nal week, we monitored must be honored. Abstracting with credit is permied. To copy otherwise, or republish, participant’s usage aer withdrawing the intervention. We hy- to post on servers or to redistribute to lists, requires prior specic permission and/or a fee. Request permissions from [email protected]. pothesized that participants who had experienced the intervention MobileHCI ’18, Barcelona, Spain conditions would use Facebook less than participants in the control © 2018 ACM. 978-1-4503-5898-9/18/09...$15.00 condition. We also hypothesized that participants in personalized DOI: 10.1145/3229434.3229463 MobileHCI ’18, September 3–6, 2018, Barcelona, Spain Fabian Okekey, Michael SobolevyΦ, Nicola DellyΨ, Deborah Estriny condition would show an increased reduction in usage than those Focus, Moment, UnGlue) provide daily feedback that summarize in the rigid condition. users’ digital habits so users can regulate their digital consumption. Our ndings show that combining nudges and negative rein- In addition to providing feedback, HCI researchers have studied the forcement successfully reduced participants’ digital overload. We regulation of overuse through application blocking on an individual found statistically signicant dierences between the three experi- level [24, 33], in groups [28, 29], as a family [27], and in a classroom mental conditions. Participants in the rigid and personalized con- [23]. Our work extends the literature by investigating an approach ditions changed their behavior but not participants in the control that does not block users’ access to services but nudges them to condition. Our results show that providing only textual feedback stop technology overuse. to participants about their daily digital consumption is not su- Our study combines nudges [53] from behavioral economics cient to change behavior. However, nudging participants via subtle, and negative reinforcement [20, 51] from behavioral psychology repetitive vibrations reduced their digital consumption by over 20% to design a digital intervention that persuades users to spend less daily during the intervention week. When the intervention was time using a target mobile app. e rst concept, nudges, refer to removed, participants returned to their baseline behavior at the interventions that steer people in a particular direction without beginning of the experiment. Although, we hypothesized that the eliminating their freedom of making the nal choice. In this paper, personalized condition would have a greater eect than the rigid we use digital nudge described by Okeke et al. [42] as “nudges condition, we did not nd any detectable dierences between these that are provided via digital technologies. Digital nudges can provide strategies. ese ndings suggest that subtle, repetitive vibrations information, reminders and planning prompts to the users in the are an eective way to reduce digital overload on mobile phones. form of status-bar messages, pop-ups, phone vibration, and phone Our intervention oers several potential benets for researchers LED display.” We chose a continual gentle vibration as our digital and practitioners. It can be applied contextually: to nudge people nudge because vibration is considered private and subtle [15]. HCI back to their social interactions when they become distracted using researchers have studied the ecacy of vibration in supporting their devices, to persuade individuals to stop using their phones stroke survivors [40], to inform users of their proximity to places in bed when it is time to sleep, to encourage individuals to return of interest during the exploration of cities [18], and to help users back to work when they become distracted by their mobile devices, gain perspective of the objects of an interactive map [46]. Our and to nudge students in educational seings to use social media work extends existing research by applying vibration to curb digital less during exam weeks when intense focus is necessary. e in- overload. tervention is easy to adopt because it is a low-cost technique that e second concept,