Architecture of Decision Support Systems

As shown in model, Decision support system consists of two major sub-systems: human decision makers and computer systems. Interpreting a DSS as only a computer hardware and software system is a common misconception. An unstructured (or semi-structured) decision by definition can not be programmed because its precise nature and structure are elusive and complex. The function of a human decision maker as a component of DSS is not to enter data to build a database, but to exercise judge or intuition throughout the entire decision-making process.


Imagine a manager who has to make a five-year production decision. The first step of the decision-making process begins with the creation of a decision support model, using an integrated DSS program such as Microsoft Excel, Lotus 1-2-3, Interactive Financial Planning Systems/Personal or Express/PC.

The user interface sub-system is the gateway to both database management systems and model-based management systems. DBMS area a set of computer programs that create and manage the database, as well as control access to the data stored within it.

The DBMS can be either an independent program or embedded within a DSS generator to allow users to create a database file that is to be used as an input to the DSS. MBMS is a set of computer programs embedded within a DSS generator that allows users to create, edit, update, and delete a model. User creates models and associated database files to make specific decisions.

The created models and database are stored in the model base and database in the direct access storage devices such as hard disks. From a user’s viewpoint, the user interface sub-system is the only part of DSS component with which they have to deal.

Therefore, providing an effective user interface must take several important issues into consideration, including choice of input and output devices, screen design, use of colors, data and information presentation format, using of different interface styles.

Today’s decision support system generator provides the user with a wide variety of interface modes: menu, based interaction mode, command language style, questions and answers, form interaction, natural language processing based dialogue, and graphical user interface (GUI). GUIs use icons, buttons, pull-down, menus, bars, and boxes extensively and have become the most widely implemented and versatile type. The interface system allows users to access to:

1. The data sub-system: (a) database (b) database management software;
2. The model sub-system: (a) model base (b) model base management software.