In the 1970 s number business organization began developing information systems which were significantly different from the information systems then in use. The new systems involved spending less resource both human and financial. The new system was interactive and was designed to help specific end users utilize data and models to discus and divide .not solve semi structured and unstructured problems.
These systems were called the decision support system and by the end of 1998 were extended to groups and entire organizations. the decision support system system are interactive information system ,that rely on a integrated set if the nurse friendly hardware and software tools to produce and present information that is targeted to support managements in the decision making process.
The decision support system assist management decision making by combining data, sophisticated analytical models and user friendly software into as single powerful system that can support semi structured or unstructured decision making .the decision support system is under user control from early inception to final implementation and daily use .decision support system helps to close the information gap to enable manager to improve quality of their decisions.
While management information system is considered useful for structured decisions, decision support system is considered to be more useful for decisions at the strategic levels ,where decision makers are often controlled with complex decisions which are beyond their human abilities to synthesize properly the factor involved.
The decision support system has basic three components:
1. The database
2. A model base
3. Decision support system software system
The decision support system is a collection of current or historical data from a number of applications or groups. It is organized in such a manner that it provides easy access for a range of application.adequate precaution is taken to ensure the data integrity while controlling the processing that keeps the data current.
1. The database
Decision support system does not create or update data rather use live organizational data so that the decisions could be taken based upon actual conditions. it would also be imperative to remember that most decision support system do not have direct access to organizational data but usually use data that have been extracted from relevant databases both internal and external and stored specifically for the decision support system.
2. The model database
A model; is an abstract representation that illustrates the component or relationship of a phenomenon. Model can be physical model, a mathematical model or a verbal model. Decision support system can make use of different types of models .the models could be classified into following three types.
1) behavioral model
The focus of behavioral models of decision support system is on studying understanding the behavior and trends among the business such behavioral relationship. The trend analysis, forecasting and the statistical analysis models belong to this category. The trend analysis indicates how different variables behave in trend setting in past and future.
A regression model shows relation between one or more variables .these types of models are largely used in the process control, marketing, philology, agricultural sciences, manufacturing.
2) Operation research model
The operation research models are mathematical model. These models represent a real life problems situation. In terms of the variables, constant and parameters expressed in algebraic equations. Linear programming, ABC analysis, mathematical programming techniques are examples of operation research model.
3) management science model
These models are developed on the principles of business management, accounting and economics and econometric. In management are the improved methods of management control are available which can be used for the management decisions. some of the management decisions .some of management system can be converted into the decision support system models.
Examples are cost reducing accounting system ,the budgetary system, the ABC analysis ,the mrp system production planning and control scheduling and loading system ,manpower planning and forecasting.
The decision support system
The decision support system permits easy interaction between the user of the system and the decision support system database and model database. And model base. The decision support system software system manages the creation ,storage and retrieval of models in the model database and integrates then with data in the decision support system database .the decision support system software a system also provides a graphic ,easy to use ,flexibly user interface that supports the dialogue between the users and the decision support system.
Characteristics of Decision Support System
While developing decision support system the focus must be on identifying a problem and a set of capabilities that user consider useful in arriving at decisions about this problem.
While developing decision support system, care must be taken to ensure that the decision support system possess the following desirable characteristics.
The key decision support system characteristics and capabilities are as follows.
1. Support for decision makers in semi structured and unstructured problems.
2. Support managers at all levels
3. Support individuals at all levels and groups
4. Support for interdependently or sequential decisions
5. Support intelligence, design, choice, and implementation.
6 Support varieties of decision processes and styles.
7. Decision support system should be adaptable and flexible
8. Decision support system should be interactive and provide ese of use
9. Effectiveness balanced with efficiency
10. Complete control by decision makers
11. Ease of development by end users
12. Support modeling and analysis
13. Data access
14. Standalone, integration and web based
Applications of Decision Support System
1.Texas oil and Gas Corporation: evaluation of potential drilling sites
2. southern railways: train development dispatching and routing
3. united airlines: flight scheduling passenger demand forecasting
4. General accident insurance: customer buying patterns and fraud detection.
5. Keycrp: targeting direct mail marketing customers.
Advantage and decision support system:
A decision support system reduces the time and efforts in collecting and analysis of data from different sources.
Decision support system facilitates in depth the quicker analysis of data for unstructured decision making
Decision support system facilitates in depth analysis of data so data structured are efficient and effectively used.
Decision support system enables the user to anticipate outcomes with the help of efficient and adhoc query facility.
Limitation of decision support system
- decision support system can’t replace human decision making talent
- Language and command interface are not sophisticated enough to low for natural processing of user directives and inquires.
- The power of decision support system is limited by the computer system upon which it is running