Systems and Information Quality Decision Support Systems Information

Systems and Information Quality Decision Support Systems

Information Systems n What is the difference between an information system and a system in general? n System n n A group of interacting components with a purpose. Every system has a boundary § Closed systems § Open systems n n n Your body Metropolitan area transportation system. Systems often incorporate feedback.

Information Systems n Information systems n Is a system whose purpose is to store, process and communicate information.

DSS As Information Systems n How does a decision support system differ from an information system in general? n An information system is a DSS, but can reach some conclusions that do not apply to all types of information systems. n n Usually uses one or more data stores Does not update the databases it used as external information sources Communicates with the decision maker The decision maker supplies the DSS with specific information defining the decision to be made.

Information and Information Quality n Difference between data and information n Data is what the information systems department creates, stores and provides. n Information is anything that reduces uncertainty. n Information is data in its business context.

Creating Information From Data n The two fundamental operations involved in turning data into information. n Comparing one data element with another n We compare the starting time of a movie with our earliest possible arrival, the projected rate of return on developing motorcycle CD players, etc. n Performing calculations on data n We calculate our earliest possible arrival time at the movie theater from the ending time of dinner and expected travel time. We compute the expected profitability of the motorcycle CD player from projected costs and revenues. n What can go wrong in the process?

The Affect of Computers on Information Quality n The eleven factors that define information quality, and the affects of computers:

The Affect of Computers on Information Quality n The eleven factors that define information quality, and the affects of computers: 1 Relevance l l l Applies to the task being performed Relevance is not an all or nothing situation A data requirements study should be on of the first parts of any DSS project

The Affect of Computers on Information Quality –Cont’d 2 Correctness l l Some correctness situations are absolute, where the data elements have no error tolerance. l A phone number is either correct or it isn’t l A catalogue number either refers to size 9 B black shoes or it doesn’t Other data elements are still correct if they are somewhat off from their actual value. l = 3. 14159 l Misspelling my name Caren Reeves instead of Karen Reaves. l It’s still correct because it refers to me, but it is inaccurate. l What’s the number one reason for incorrect data?

The Affect of Computers on Information Quality –Cont’d 3 Accuracy l l The accuracy of a data element is a measure of how close it is to its real world value. The accuracy information quality factor allows for some errors in the underlying data l l Knowing the outdoor temperature to within 5 degree Fahrenheit or so is sufficient to guide our choice of clothing Most automobile odometers are accurate to about 2 percent.

The Affect of Computers on Information Quality –Cont’d 4 Precision l The precision of a data element is the maximum accuracy that can be represented by the way a data element is stored in a computer and presented to its users. l Corporate earnings per share usually stated to the nearest cent, even when the input data can provide correct tenths or hundredths of a cent. l Graphs are seldom highly precise l Color coding requires classifying data into a few ranges

The Affect of Computers on Information Quality –Cont’d 5 Completeness l Completeness means that it includes all the necessary elements for the decision that is to be made and that each element is based on all relevant factors

The Affect of Computers on Information Quality –Cont’d 6 Timeliness n Refers to relationships among three items: n n n The time that information is needed The time that information is made available The time that its underlying data was obtained Information must reflect up-to-date data n Information must be available in time for its intended use n

The Affect of Computers on Information Quality –Cont’d 7 Usability n How quickly and easily its intended users can figure out what they need to know from what they see. n High quality information is presented in a usable format.

The Affect of Computers on Information Quality –Cont’d 8 Accessibility n This means that authorized people can obtain it quickly, with an acceptable level fo effort, from places in which they are expected to be when they need it. 9 Conformity to expectations n Is how well the information’s processing, timeliness, and so on match what this person expects.

The Affect of Computers on Information Quality –Cont’d 10 Consistency n Means that all data elements that contribute to an information item, or a set of related items, are based on the same assumptions, definitions time period, and other factors 11 Cost of information n The cost of anything is a measure of the resources, translated into financial terms, that an organization must expend to obtain it.