Knowledge Representation, Declarative knowledge, Procedural knowledge

Knowledge Representation

Knowledge is the information about a domain that can be used to solve problems in that domain. In order to solve many problems, it requires much knowledge and this knowledge must be represented in the computer. As a part of the designing a program to solve problems we must define how the knowledge will be represented. A representation scheme is referred to as the form of the knowledge that is used in an agent. A representation of some of the parts of the knowledge is the internal representation of the knowledge. A representation scheme specifies the form of the knowledge. A knowledge base is the representation of the entire knowledge that is stored by an agent.

A good representation scheme is a compromise among many competing objectives. A representation should be the following:

• It should be rich enough to express the knowledge that is needed to solve the problem.
• As close to the problem as possible it should be compact, natural and well-maintained. It should be easy to see the relationship between the representation and the domain that is being represented so that we can determine whether the knowledge represented is correct. A small change in the problem should also result in a small change itself while in the representation of the problem.
• It should be amenable to efficient computation which generally means that it is capable of expressing the features of the problem that can be exploited for computational gain and to trade off the accuracy and the computation time.
• It should be capable of being acquired from people, data, and the past experiences.

Declarative knowledge:

The declarative knowledge is understood as the passive knowledge in the form of statements of facts about the world. For example - A mark statement of a student is declarative knowledge. Declarative knowledge is defined as the factual information which is stored in memory and also it is known to be static in nature. There are many names that are given to the declarative knowledge such as descriptive knowledge, propositional knowledge and so on. It is the part of knowledge which describes how things are. The things or the events or the processes along with their attributes and the relations between these things,events or processes and their attributes define the domain of declarative knowledge.

Procedural knowledge:

The procedural knowledge is generally a compiled or a processed form of the information. Procedural knowledge is related to the performance of some specific task. For example, a sequence of steps to solve a problem is procedural knowledge. Procedural knowledge is different from other kinds of knowledge such as declarative knowledge in the fact that it can be directly applied to a task. For instance, one uses the procedural knowledge to solve problems differs from one possesses the declarative knowledge about problem solving because this knowledge is formed by doing. Procedural knowledge is a type of knowledge that can be possessed by an intelligent agent. Such knowledge is often represented as a partial or complete finite-state machine or computer program.

References:

1. Elaine Rich, Kevin Knight 1991, "Artificial Intelligence".
2. Nilsson, Nils J. Principles of Artificial Intelligence, Narosa Publishing House New Delhi, 1998.
3. Norvig, Peter & Russel, Stuart Artificial Intelligence: A modern Approach, Prentice Hall, NJ, 1995
4. Patterson, Dan W. Introduction to Artificial Intelligence and Expert Systems, Prentice Hall of India Private Limited New Delhi, 1998.