This document discusses information systems and decision support systems. It defines an information system as a system whose purpose is to store, process, and communicate information. A decision support system is defined as an information system that uses one or more databases to provide information to support decision making, does not update the databases it uses, and communicates with the decision maker. The document also discusses information quality and factors that impact quality such as relevance, correctness, accuracy, and timeliness.

2. Information &
Information Quality
Introduction to
Systems
DSS as an IS
Information
Systems (IS)
Chapter
3

3. Introduction to
Systems
Information &
Information Quality
DSS as an IS
Information
Systems (IS)
Chapter
3
System?
groupa of
interacting components
with a purpose

4. Information &
Information Quality
DSS as an IS
Information
Systems (IS)
Chapter
3
Introduction to
Systems
systems that has something crosses
its boundary in either direction.
systems that has nothing crosses its
boundary in either direction.
Each system has a boundary - separates the components of that systems
(which are inside it) from its environment.

5. Information &
Information Quality
DSS as an IS
Information
Systems (IS)
Chapter
3
Introduction to
Systems
Systems always incorporate feedback : output from a systems
component that becomes input to a systems component.
Systems that do not use
feedback to adjust their
outputs
Systems that use feedback to adjust
their outputs, based on how well
the result of those output matches
the desired result.

6. Information &
Information Quality
DSS as an IS
Chapter
3
Introduction to
Systems
Information
Systems (IS)
Information
Systems (IS)
is a system
whose purpose is to
In 1990’s we often associate IS with computer,
however, an IS need not use computers.
store
process
communicate

7. Information &
Information Quality
Information
Systems (IS)
Chapter
3
Introduction to
Systems
DSS as an IS
uses one or more data stores (database or set of files) that
provide information to support the decision.
does not update the databases that it uses as external
information sources.
communicates with the decision maker.
decision maker supplies specific information defining the decision
to be made within the general category of decisions with which th
DSS can help - tells the DSS what data to extract.

8. Information &
Information Quality
Information
Systems (IS)
Chapter
3
Introduction to
Systems
DSS as an IS
Data
Retrieval
Modeling
Data
Analysis
Database
Decision maker
Data for analysis
Model input Model results
Commands
Results
Answer
Queries
Commands
Extracted
Data

9. DSS as an IS
Information
Systems (IS)
Chapter
3
Introduction to
Systems
Information &
Information Quality
Raw facts Processed data
comparing one data
element with another
performing calculations on
data.

10. DSS as an IS
Information
Systems (IS)
Chapter
3
Introduction to
Systems
Information &
Information Quality
degree of excellence in the context of the
intended use.
Quality of Information : the value of that information for its
intended purpose
Factors
Relevance
Correctness
Accuracy
Precision
Completeness
Timeliness
Usability
Accessibility
Consistency
Conformity to
expectation
Cost