photo by Stephen Crowers

Interactions on the Move:
Understanding Strategy Adaptation in Dynamic Multitask Environments

Duncan Brumby (PI)

Chris Janssen (PhD student)

Justin Grace (RA)

Collaborators: Dario Salvucci (Drexel Univerisity) and Andrew Howes (University of Manchester)


project news

- welcome to Justin Grace

Justin Grace

november 2009

Justin Grace joins us from the University of Edinburgh, where he studied Human Cognitive Neuropsychology (MSc) and Psychology and Linguistics (MA). Justin has interests in how executive functioning and working memory systems control multitasking behavior.

- we're hiring

september 2009

We are looking to hire a Research Assistant who will be responsible for the running of experiments aimed at investigating how people perform multiple ongoing tasks while driving. Candidates should have a degree in Psychology (or equivalent subject) and have experience of running controlled experiments with human subjects. Effective working knowledge of statistical data analysis tools is essential (preferably R). Working knowledge of JAVA is desirable. This post is flexible in terms of working hours. It can be either a full-time position for one year starting November 2009, or a half-time position for two years. Closing date for applications is October 1st 2009. This is an exciting opportunity to join a vibrant HCI group at London's leading research university.
[job description] [apply]


- poster presented at ICCM and CogSci

july/august 2009

Chris Janssen presented the results of a study conducted in our lab at the 9th International Conference on Cognitive Modeling (ICCM 2009) in Manchester, and at the annual meeting of the Cognitive Science Society (CogSci 2009) in Amsterdam. The study was conducted as part of Chris' PhD work on dual-task strategy adaptation. The study found that people actively reconfigure the way in which they perform a simple dialing task to meet dual-task demands. [project publications]

- paper presented at CHI'09

april 2009

Duncan Brumby presented a full paper at the ACM SIGCHI conference (CHI'09) in Boston. The paper investigates how people adapt their multitasking strategy to varying task objectives. The
question of how objectives shape multitasking strategies is an important one for Human-Computer Interaction research given the field's promotion of mobile technologies. A better understanding will greatly facilitate the design, prototyping, and evaluation of such technologies in the context of how people actually use them in dynamic multitask contexts. [project publications]



project summary

With computers having been untethered from the relative safety of the desktop there comes a growing need to understand the implications of interface design for how people interact with information communication technologies on the move. Nowhere is this need greater than in situations where people interact with technology systems in safety critical environments, such as when driving a car. In many such multitasking situations, people can often only actively attend to a single task at a time because of competition for limited attentional resources between tasks. At the same time many of our interactions with technology systems tend to be shaped by prior knowledge of how to perform routine procedural tasks on that device. It is therefore not clear to what extent decisions about how to interleave attention between tasks is constrained by this prior experience of using a device. If people do not adjust their interaction style to the demands of the task environment this could be potentially dangerous.

There are a number of accounts for how people might choose to interleave resources between tasks. One possibility is that task interleaving is constrained to natural break points in the execution of a task. For example, consider a driver dialling a telephone number. In this situation, the driver might choose to enter only the area-code part of the telephone number (or indeed select the ‘Address Book’ option from an interactive menu), and then return attention to monitoring the road ahead before completing another small step of the secondary task. In this way, natural break points in the representational structure of the task act as a cue to switch from one task to another. Alternatively, drivers might simply set a limit (or threshold) on the amount of time they are prepared to look away from the road and complete as much of the secondary task as possible within this window of opportunity. A further possibility is that task interleaving strategies are selected that optimally trade the time required to complete the secondary task against any additional time taken to switch to the primary driving task in order to maintain a stable lane position while dialling.

This research proposal sets out a series of planned experiments that will be conducted to investigate how people allocate resources between multiple ongoing tasks while driving. Experiments will be conducted in a desktop driving simulator using specially instrumented devices for secondary task interactions. The experiments will be informed by various computational accounts of how people might choose to schedule resources between tasks, and will investigate the consequences of manipulating the representational structure of secondary in-car tasks and features of the functional task environment on performance and strategy adaptation. In tandem with the running of these experiments, modelling will be conducted that will implement these various computational accounts of human multitask scheduling, deriving key quantitative performance predictions for each. This modelling work will be aimed at determining which account provides the best characterisation of human behaviour, and in doing so, will set the foundation for future work directed towards developing design tools for rapidly predicting the efficiency of design alternatives for supporting the multitasking user on the move.

This programme of research will lead to greater understanding of human behaviour in complex multitasking environments and the knowledge gained will be of potential value to the designers of mobile interactive systems. The empirical data will give insights into how interfaces for in-car devices might be redesigned to support users’ needs in a safe and efficient manner. These conclusions will be of value for understanding behaviour in a variety of contexts where people must allocate attention between multiple concurrent task while monitoring safety critical systems.

project publications

Brumby D.P., Salvucci, D.D., & Howes, A. (2009). Focus on driving: How cognitive constraints shape the adaptation of strategy when dialing while driving. In the Proceedings of the SIGCHI Conference on Human Factors in Computing Systems (CHI 2009), Boston, MA, April 4–9, 2009 (pg. 1629-1638). New York, NY: ACM Press. [DOI]

Janssen, C.P., & Brumby D.P. (2009). Dual-task strategy adaptation: Do we only interleave at chunk boundaries? Poster to be presented at 9th International Conference on Cognitive Modeling. Manchester, UK.

Janssen, C.P., & Brumby D.P. (2009). Dual-task strategy adaptation: How task structure is actively reconfigured for improved performance. Poster to be presented at The 31st Annual Conference of the Cognitive Science Society. Amsterdam, The Netherlands.