helen.parker@btinternet.com
or
h.parker@shu.ac.uk
My talk concerns our present (and rather limited) understanding of user requirements for the timing of computer interface behaviour, in the performance of computer-aided tasks.
My interest lies in understanding what happens to users - what cognitive processes are at work - when the pace of user activity is driven by the pace of activity at the computer interface and when that pace is inappropriate to user needs. Specifically, how do we respond when delayed by slow system response times (in Web browsers and other remote communication processes); how do we respond when interrupted by irrelevant, but seemingly urgent information from "background" computer processes, which are not the focus of our present activity?
This talk focuses on the idea of "temporal coherence" and properties of temporally coherent event structures, originally identified in the literature on music perception and the understanding of film narrative, as environmental properties which are important to attention, understanding and recall. When the behaviour of the computer interface delays us, interrupts us and presents us with temporal irrgularity, temporal coherence is lost.
Two questions arise here. Firstly, what evidence do we have that temporally coherent interface behaviour does significantly and positively affect the understanding, satisfaction and performance of users? What does the history of response-time studies have to tell us? Secondly, what is the potential relevance of temporal coherence to the design of temporally usable computer interfaces?
Two candidate approaches to design present themselves: i) the design of interface agents which maintain a temporal awareness of both underlying computer processes and user task processes and which manage the timing of computer process response to match the timing of user tasks; ii) the design of interface behaviour which actively promotes effective user strategies in the face of interruption and delay. The feasibility of both approaches will be discussed.