Knowledge Representation Environments: An Investigation of the CASSMs between Creators, Composers and Consumers

Many systems form ‘chains’ whereby developers use one system (or
‘tool’) to create another system, for use by other people. For example, a web development tool is created by one development team then used by others to compose web pages for use by yet other people. Little work within Human–Computer Interaction (HCI) has considered how usability considerations propagate through such chains. In this paper, we discuss three-link chains involving people that we term Creators (commonly referred to as designers), Composers (users of the tool who compose artefacts for other users) and Consumers (end users of artefacts). We focus on usability considerations and how Creators can
develop systems that are both usable themselves and also support Composers in producing further systems that Consumers can work with easily. We show how CASSM, an analytic evaluation method that focuses attention on conceptual structures for interactive systems, supports reasoning about the propagation of concepts through Creator–Composer–Consumer chains. We use as our example a knowledge representation system called Tallis, which includes specific implementations of these different perspectives. Tallis is promoting a development culture within which individuals are empowered to take on different roles in order to strengthen the ‘chain of comprehension’ between different user types.