Page 49 - DCAP208_Management Support Systems

Management Support Systems

Notes 4.1 Dialogue Management for DSS

While the quality and reliability of modeling tools and the internal architectures of DSSs are
important, the most crucial aspect of DSSs is, by far, their user interface. Systems with user
interfaces that are cumbersome or unclear or that require unusual skills are rarely useful and
accepted in practice. The most important result of a session with a DSS is insight into the decision
problem. In addition, when the system is based on normative principles, it can play a tutoring
role; one might hope that users will learn the domain model and how to reason with it over
time, and improve their own thinking.
A good user interface to DSSs should support model construction and model analysis, reasoning
about the problem structure in addition to numerical calculations and both choice and
optimization of decision variables.

The term “process” in the context of user interface process refers to the flow of information
(a) from the user to the system and (b) from the system to the user. It is handled by the User
Interface Management System (UIMS). The UIMS processes user commands, issued in whatever
action language it requires, and passes them on to the data and model management subsystems.
In the reverse direction, it presents information from those subsystems to the user.

Notes Increasingly, the action language is based on Web or operating system GUI concepts.
It may also incorporate natural language processing capabilities.

4.1.1 Support for Model Construction and Model Analysis

User interface is the vehicle for both model construction (or model choice) and for investigating
the results. Even if a system is based on a theoretically sound reasoning scheme, its
recommendations will be as good as the model they are based on. Furthermore, even if the
model is a very good approximation of reality and its recommendations are correct, they will
not be followed if they are not understood. Without understanding, the users may accept or
reject a system’s advice for the wrong reasons and the combined decision-making performance
may deteriorate even below unaided performance. A good user interface should make the
model on which the system’s reasoning is based transparent to the user.
Modeling is rarely a one-shot process, and good models are usually refined and enhanced as
their users gather practical experiences with the system recommendations.

!
Caution It is important to strike a careful balance between precision and modeling efforts;
some parts of a model need to be very precise while others do not.

A good user interface should include tools for examining the model and identifying its most
sensitive parts, which can be subsequently elaborated on. Systems employed in practice will
need their models refined, and a good user interface should make it easy to access, examine, and
refine its models.

4.1.2 Support for Reasoning about the Problem Structure in Addition to
Numerical Calculations

While numerical calculations are important in decision support, reasoning about the problem
structure is even more important. Often when the system and its model are complex it is insightful

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