Integral Logistics Management — Operations Management and Supply Chain Management Within and Across Companies

20.2.1 Basic Principles of Modeling

Intended learning outcomes: Describe, as a basic problem in modeling, how the quality of a system image is affected by the person who designs the model.

The storing, processing, and presenting of information are associated with typical design tasks. To carry out these tasks effectively, it is necessary to have an exact idea of the items or facts to which the information refers.

A model is defined by [MeWe18] as a description or analogy used to help visualize some­thing; a system of postulates data, and inferences presented as a mathematical description of an entity or states of affairs; also: a computer simulation based on such a system.

The term modeling denotes the procedure that leads to the result, namely, the model.
A modeling method is a planned and systematic approach used for modeling.

Models for information systems are not material but are instead the mental models that a person has of objects or circumstances/issues. People develop their ideas of things based on personal experience and learning about the system itself (for example, about the company), its goals, structure, and processes, but also based on concrete visible objects and their functio­ning. This leads immediately to one of the main difficulties: A model tends to carry the personal stamp of the person who designed the model. Figure shows this problem.

Fig.       A basic problem in modeling: The quality of a system image is affected by the person who designs the model. From [Norm13].

According to [Norm13, p.16], “the designer expects the user’s model to be identical to the design model. But the designer doesn’t talk directly with the user — all communication takes place through the system image. If the system image does not make the design model clear and consistent, then the user will end up with the wrong mental model.” When modeling physical systems, such as goods flow in the company, it is already difficult to achieve models that everyone sees as being generally the same. This is all the more difficult when mod­eling information systems. There are few restrictions placed on imagination and creativity. But this is a disadvantage for communication among several staff members.

Reality shows that the desired single and generally valid model for an information system of a company cannot be found. The modeling of operational information systems is conducted from different views, which accord with the different mental models. This corresponds to the complexity of such sociotechnical systems. In the following, the objective is to find a common framework in which the various models can be arranged.

The different methods of modeling are themselves different, depending on the purpose. Each method has specific advantages. Thus, if due to personal background or experience individuals view a certain aspect as especially important, they will find the corresponding method to be especially suitable.

Course section 20.2: Subsections and their intended learning outcomes