Managing
the Ecology of Interaction
Alan Dix
Lancaster University, Computing Department,
Lancaster, UK.
Many studies and many areas in HCI and
CSCW emphasise the rich ecological setting of human–computer interaction:situated
action, distributed cognition, activity theory, ethnomethodological studies.Often
those who espouse rich understanding of interaction contrast it with more
formal models and reject these as inappropriate for capturing the complexity
of human experience and activity.
In the biological disciplines, an appreciation
of the complexity of ecological interactions was also a long time coming.However,
those studying the biosphere or environmental management do not stop at
saying that it is complex, but seek to analyse and model these interactions
in order to predict the effects of interventions and manage threatened
ecosystems.Similarly, in formal
areas of human–computer interaction we need to accept the limitations of
our formalisms, but also extend them to incorporate the richer interactions
with the work or home environment.
In this context I will discuss a variety
of issues that can inform or form part of our formal models:
- the
socio-organisational Church–Turing hypothesis – that organisations
perform information processing and thus share features with cognitive and
electronic computation;
-
triggers
– understanding why things happen when they happen,
-
artefacts
– that embody information not just in what they are, but also where they
are and how they are disposed in the workplace,
-
information
– how people use sources to drive and inform their actions
-
incidental
interaction – systems that respond because people have acted for some other
purpose.
These can be seen as part of a broader
theoretical perspective of embodied computation – that real computation
happens in the physical world and that the physical and human world is
full of computation.
By having a rich and, where appropriate,
formalised, understanding of the ecology of human–human and human–computer
interaction, we are better placed to ensure that our interventions in the
workplace do not lead to ecological catastrophes in the organisation.
[back]
Tools
for Task Modelling:Where we are, Where we
are headed
Fabio
Paterno
ISTI
- C.N.R.,
Pisa, Italy
One
universally agreed upon design principle for obtaining usable interactive
systems is “Focus on the users and their tasks”. Indeed, among the
relevant models in the human-computer interaction field, task models play
an important role, because they represent the logical activities that should
support users in reaching their goals. Thus, knowing the tasks necessary
to goal attainment is fundamental to the design process. Task models represent
the intersection between user interface design and more formal software
engineering approaches by providing designers with the means to represent
and manipulate a formal abstraction of goal-oriented activities.
While task modelling
and task-based design are entering into current practise in the design
of interactive systems, there is still a lack of tools supporting the interactive
analysis of task models. The purpose of such tools is to ease the creation,
analysis and modification of such representations and simulation of their
dynamic behaviour.
This talk will provide
a discussion of a set of functionalities that can be useful to support
the analysis of task models and that are supported by the CTTE tool (http://giove.cnuce.cnr.it/ctte.html),
such as the possibility of representing concurrent tasks, cooperative tasks;
calculating metrics, highlighting meaningful features of the task model
and allowing comparison among different task models for the same interactive
system; performing reachability analysis; interactive simulation of their
dynamic behaviour; identifying relationships among scenarios and task models,
and so on. Particular attention will be paid to explaining why such functionalities
are useful for designers and evaluators of interactive systems. This set
of functionalities can be used to create a taxonomy useful to compare tools
for task modelling. How other tools are positioned in this taxonomy will
be discussed. The CTTE tool is currently used in the CAMELEON project (http://giove.cnuce.cnr.it/cameleon.html)
to support the design of multi-platform applications (applications that
can be accessed through a variety of interaction platforms).
The last part of
the talk will be dedicated to discussing further functionalities that can
be helpful for such tools, thus providing a research agenda for those interested
in these topics.
[back]
