Reducing Users’ Perceived Mental Effort due to Interruptive Notifications in Multi-Device Mobile Environments

August 8, 2015


In today’s ubiquitous computing environment where users carry, manipulate, and interact with an increasing number of networked devices, applications and web services, human attention is the new bottleneck in computing. It is therefore important to minimize a user’s mental effort due to notifi- cations, especially in situations where users are mobile and using multiple wearable and mobile devices. To this end, we propose Attelia II, a novel middleware that identifies break- points in users’ lives while using those devices, and delivers notifications at these moments. Attelia II works in real-time and uses only the mobile and wearable devices that users naturally use and wear, without any modifications to applications, and without any dedicated psycho-physiological sensors. Our in-the-wild evaluation in users’ multi-device en- vironment (smart phones and smart watches) with 41 par- ticipants for 1 month validated the effectiveness of Attelia. Our new physical activity-based breakpoint detection, in ad- dition to the UI Event-based breakpoint detection, resulted in a 71.8% greater reduction of users’ perception of workload, compared with our previous system that used UI events only. Adding this functionality to a smart watch reduced workload perception by 19.4% compared to random timing of notifica- tion deliveries. Our multi-device breakpoint detection across smart phones and watches resulted in about 3 times greater reduction in workload perception than our previous system.

This research is a joint research between Ubicomp lab. in HCII, SCS, CMU and Tokuda lab. in Keio University.

T. Okoshi, J. Ramos, H. Nozaki, J. Nakazawa, A. Dey and H. Tokuda. Reducing Users’ Perceived Mental Effort due to Interruptive Notifications in Multi-Device Mobile Environments. In Proceedings of The 2015 ACM International Joint Conference on Pervasive and Ubiquitous Computing (UbiComp’15), p475-486, Sep. 2015.

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 Anind K Dey Julian Ramos Tadashi Okoshi

Ubicomp '15

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