Decision Support Systems


Definition: A Decision Support System (DSS) is an umbrella term used to describe any computer application that enhances the user’s ability to make decisions. More specifically, the term is usually used to describe a computer-based system designed to help decision-makers use data, knowledge and communications technology to identify problems and make decisions to solve those problems.

Types of DSS

Since the definition of Decision Support Systems can be stretched to include almost any application that processes data there is some confusion as to exactly what constitutes a DSS. In an effort to clarify the term, DS systems can be separated into seven broad categories, each aiding decision making by different methods.

* Communications Driven DSS

A C-D DSS is a type of DSS that enhances decision-making by enabling communication and sharing of information between groups of people. At its most basic level a C-D DSS could be a simple threaded e-mail. At its most complex it could be a web-conferencing application or interactive video.

Communication-Driven DSS will exhibit at least one of the following characteristics:

Supports coordination and collaboration between two or more people;
Facilitates information sharing;
Enables communication between groups of people;
Supports group decisions.

* Data-Driven DSS

Data-driven DSS are a form of support system that focuses on the provision of internal (and sometimes external) data to aid decision making. Most often this will come in the form of a data warehouse – a database designed to store data in such a way as to allow for its querying and analysis by users.

Another example of a data-driven DSS would be a Geographic Information System (GIS), which can be used to visually represent geographically dependant data using maps.

* Document-Driven DSS

Decision Support SystemsDocument-driven DSS are support systems designed to convert documents into valuable business data. While data-driven DSS rely on data that is already in a standardised format that lends itself to database storage and analysis, document-driven DSS makes use of data that cannot easily be standardised and stored.

The three primary forms of data used in document driven DSS are:

Oral (i.e. transcribed conversations);
Written (i.e. reports, memos, e-mail and other correspondence);
Video (i.e. TV commercials and news reports).

None of these formats lend themselves easily to standardised database storage and analysis, so managers require DSS tools to convert them into data that can be valuable in the decision making process.

Document-driven DSS is the newest field of study in Decision Support Systems. Examples of document-driven tools can be found in Internet search engines, designed to sift through vast volumes of unsorted data through the use of keyword searches.

* Knowledge-Driven DSS

Knowledge-driven DSS are systems designed to recommend actions to users. Typically, knowledge-driven systems are designed to sift through large volumes of data, identify hidden patterns in that data and present recommendations based on those patterns.

* Model-Driven DSS

Model-driven support systems incorporate the ability to manipulate data to generate statistical and financial reports, as well as simulation models, to aid decision-makers. Model-based decision support systems can be extremely useful in forecasting the effects of changes in business processes, as they can use past data to answer complex ‘what-if’ questions for decision makers.

In addition to these basic types of DSS there are also two additional factors: whether the DSS is spreadsheet-based, web-based or something else entirely.

* Spreadsheet-based DSS

Model- and Data-driven DS systems can be built using spreadsheets. Spreadsheets offer decision-makers easy to understand representations of large amounts of data. Additionally, spreadsheet data is arranged in such a way as to make it easy to convert the data into visualisations to further aid decision-makers.

* Web-based DSS

Any type of DSS can be web-based. The term simply describes any decision support system that is operated through the interface of a web browser, even if the data used for decision support remains confined to a legacy system such as a data warehouse.

Scope of DSS

In addition to these basic types of Decision Support System there are also two separate categories used to define systems.

* Enterprise-wide DSS

Enterprise-wide DS systems are systems that are linked into large data warehouses, and offer decision support to managers at all levels of an enterprise. Enterprise-wide systems will typically be basic, general use systems that can perform a wide variety of functions.

* Desktop DSS

Desktop DS systems are much smaller applications designed to be run from a desktop PC. While these systems may well be linked into a data warehouse or other large volume of data, they will typically be more limited in scope.

An example of a desktop DSS is Microsoft Excel, the desktop spreadsheet application.