Lessons learned from manual systems: designing information systems based on the situational theory of agency - Information Systems Foundations: Constructing and Criticising - page 170

6. Identify choices remaining within the situations within activities that are not accom-
modated by environmental affordances. This will define the function of the informational
component of the system, which will allow all choices to be resolved by reference to it.
In situated systems the information system component is minimal and remains
simply to provide aspects that resolve situations that prevent activities from becom-
ing routine
The final methodology would consist of detailed documented guidelines for performing
these steps together with appropriate representational analytical tools.
Thus far, the only experience in analysing situational systems in the literature is for
designing robots and software agents. It has not been explicitly applied to socio-technical
systems. However, there exist evolved routine work systems involving human actors
and we are interested in examining their workings with respect to each of the theories
of agency and drawing conclusions about how they work based on the examination.
Should they be found to be consistent with the situational theory of agency, we may
add depth to our understanding of the characteristics of situational systems. Con-
sequently, in the following section we discuss three cases of evolved manual systems
supporting routines. Manual systems are used in this paper because they are examples
of effective situational systems. The design methodology for situational information
systems assumes that agent environments, sensing mechanisms for situations, and actions
may need to be designed from scratch and are thus 'blue sky'. Fine-tuning will be re-
quired where any unreliable activities are found: essentially 'tweaking' them to make
them more effective. Fine-tuning will involve further moulding of the environment and
improvement in sensing situations.
Learning from evolved manual systems
In this section we examine three user-designed routine systems in air traffic control,
small-scale manufacturing (the Cash System), and large-scale lean manufacturing (the
Kanban System). These systems have all been described in the literature and are inter-
esting because their design does not fit traditional approaches to systems analysis and
design. Although these are all manual systems, we do not intend our methodology to
be applied purely to manual systems. But despite the fact that the systems we examine
are manual, they can nevertheless give us important insights into how situated users
view and represent their immediate situation (as opposed to the aerial view of the world
used in the deliberative theory). In this section we examine each of the systems by ex-
ploring three things: what is being represented, what theory of agency is more likely
to be useful in explaining its workings, and what features it has that may be helpful
when designing systems to support similar cases.
The structure of the section is as follows: in each subsection, we describe each system,
discuss the approach to representation in the system, and classify the system as likely
to be either situational or deliberative. We conclude the section with a discussion of
what this tells us about designing situational systems.
Air traffic control: landing by the strips system
Airports have traditionally used a largely manual system for landing planes (Mackay et
al., 1998). The system is still respected and used in many places, and in this sense is re-
silient. The system is routine and has an air traffic controller seated in front of a radar
screen at an angled table of flight strips. The flight strips can be placed on the table in
various configurations in relation to each other. Each airport has several air traffic con-
trollers controlling different parts of the air space around the airport.