It is an information processing system within a decision making framework. This article details some of the definitions, theories and practices used in the construction of Decision Support Systems. This confidence level is often given a probability factor which acts as a weight in the decision making process. So if one piece of knowledge has proven true on many occasions them it will have a high level of probability and if it is untested and based on 'gut feeling' then it will have a correspondingly low level of probability Assumptions must be made about values used in any decision made. Knowledge is used to combat the uncertainty in arriving at a best decision.
Errors can be due to instrumental or conceptual problems in measuring the data.
Decision Support Systems help to manage the uncertainty of data , they take the data and turn it into a decision. Knowledge is a guide to informed practice. The process which the system takes the user through should lead to greater understanding and the formation of plans. It helps the user make concrete sense out of the abstract. Most computer based systems separate the knowledge base from the inference engine.