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Glossary Contents

Decision Support Systems Glossary

by D. J. Power

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A B C D E

F G H I J

K L M N O

P Q R S T

U V W X YZ




D

Daemon
A computer program or procedure that is automatically activated when it recognizes a specific, predefined state or condition.

Data
Binary (digital) representations of atomic facts, text, graphics, bit-mapped images, sound, analog or digital live-video segments. Data is the raw material of a system supplied by data producers and is used by information consumers to create information.

Data Conferencing
This term refers to a communication session in which two or more participants are sharing computer-based data in real-time. Any participants' keyboard/mouse can control screens of other participants. Voice communication can be out-of-band using a totally separate voice connection or in-band using a simultaneous voice and data technology.

Data Dictionary
A database about data and database structures. A data dictionary is a catalog of all data elements that contains their names, structures, and information about their usage. It is a central location for metadata. Normally, data dictionaries are designed to store a limited set of available metadata, concentrating on the information relating to the data elements, databases, files and programs of implemented systems.

Data-Driven DSS
This type of Decision Support System emphasizes access to and manipulation of a time-series of internal company data and sometimes external data. Simple file systems accessed by query and retrieval tools provide the most elementary level of functionality. Data warehouse systems that allow the manipulation of data by computerized tools tailored to a specific task and setting or by more general tools and operators provide additional functionality. Data-driven DSS with On-line Analytical Processing (OLAP) or data mining tools provide the highest level of functionality and decision support that is linked to analysis of large collections of historical data. Early, very limited versions of Data-Driven Decision Support Systems were called Data-Oriented (Alter, 1980) or Retrieval-Only DSS by Bonczek, Holsapple and Whinston (1981).

Data Element
The most elementary unit of data that can be identified and described in a dictionary or repository which cannot be subdivided.

Data Mining
A class of analytical applications that search for hidden patterns in a data base. Data mining is the process of sifting through large amounts of data to produce data content relationships. This is also known as data surfing. Data mining tools use a variety of techniques including case-based reasoning, data visualization, fuzzy query and analysis, and neural networks. Case-based reasoning tools provide a means to find records similar to a specified record or records. These tools let the user specify the "similarity" of retrieved records. Data visualization tools let the user easily and quickly view graphical displays of information from different perspectives. For more information, please check the data mining FAQ at http://www.rpi.edu/~vanepa2/faq.html.

Data Quality
High quality data is accurate, timely, meaningful, and complete. DSS must have high quality data; low quality data can result in bad decisions. Assessing or measuring data quality is a preliminary task associated with evaluating the feasibility of a data-driven DSS project.

Data Visualization
This term refers to presenting data and summary information using graphics, animation, 3-D displays, and other multimedia DSS tools.

Data Warehouse
A database designed to support decision making in organizations. It is batch updated and structured for rapid online queries and managerial summaries. Data warehouses contain large amounts of data. A data warehouse is a subject-oriented, integrated, time-variant, nonvolatile collection of data in support of management's decision-making process. Check "What is a Data Warehouse" by W.H. Inmon at http://www.cait.wustl.edu/ cait/papers/prism/vol1_no1/ According to Ralph Kimball "A data warehouse is a copy of transaction data specifically structured for query and analysis" (see Kimball, R. The Data Warehouse Toolkit: Practical Techniques for Building Dimensional Data Warehouses. 1996. Also, see Greenfield, L. A Definition of Data Warehousing.)

Decision
The choice of one from among a number of alternatives; a statement indicating a commitment to a specific course of action.

Decision Analysis Tools
DA tools help decision makers decompose and structure problems. The aim of these tools is to help a user apply models like decision trees, multi-attribute utility models, bayesian models, Analytical Hierarchy Process (AHP), etc. Examples of DA software packages include AliahThink, BestChoice3, Criterium Decision Plus, DecideRight, DecisionMaker, Demos, DPL, Expert Choice, Strad, Supertree, and Which and Why.

Decision Room
A physical arrangement for a group DSS in which workstations are available to participants. The objective for using a Decision Room is to enhance and improve the group's decision-making process.

Decision Support Systems
Interactive computer-based systems intended to help decision makers utilize data and models to identify and solve problems and make decisions. The "system must aid a decision maker in solving unprogrammed, unstructured (or "semistructured") problems...the system must possess an interactive query facility, with a query language that ...is ...easy to learn and use (Bonczek, Holsapple & Whinston, 1981; p. 19)". DSS help managers/decision makers use and manipulate data; apply checklists and heuristics; and build and use mathematical models. According to Turban (1990), a DSS has four major characteristics: DSS incorporate both data and models; they are designed to assist managers in their decision processes in semi-structured or unstructured tasks; they support, rather than replace, managerial judgment; and the objective of DSS is to improve the effectiveness of the decisions, not the efficiency with which decisions are being made (cf., p. 9).

Decision Systems
Computer based programs and technologies intended to make routine decisions, monitor and control processes, and aid or assist decision makers in semi-structured and/or non-routine decision situations.

Decision Variables
In a Model-Driven DSS a decision variable is a changing factor in the model that is determined by a decision maker. They are sometimes called independent variables and the range of values for the decision variables constrain the choices of the decision maker.

Descriptive Model
Physical, conceptual or mathematical models that describe situations as they are or as they actually appear.

Deterministic Model
Mathematical models that are constructed for a condition of assumed certainty. The models assume there is only one possible result (which is known) for each alternative course or action.

Development Environment
A Development Environment is used by a designer/builder. A development environment typically includes software for creating and maintaining a knowledge base and software for the inference engine.

Dialog Generation and Management System (DGMS)
A software management package in a DSS whose functions in the dialog subsystem is similar to that of a DBMS in a database (see Sprague and Carlson, 1982, Ch. 7).

Dialog System
The hardware and software that create and implement a user interface for a DSS. A DSS dialog system creates the human-computer interface.

Document-Driven DSS
It integrates a variety of storage and processing technologies to provide complete document retrieval and analysis. The Web provides access to large document databases including databases of hypertext documents, images, sounds and video. Examples of documents that would be accessed by a Document-Based DSS are policies and procedures, product specifications, catalogs, and corporate historical documents, including minutes of meetings, corporate records, and important correspondence. A search engine is a powerful decision-aiding tool associated with a Document-Driven DSS (cf., Fedorowicz, 1993, pp. 125-136).

Domain Expert
A person who has expertise in the domain in which a specific expert system is being developed. A domain expert works closely with a developer (known as a knowledge engineer) to capture the expert's knowledge (especially rule and relationship information) in a computer readable representation often called a knowledge base.

Drill Down/Up
An analytical technique that lets a DSS user navigate among levels of data ranging from the most summarized (up) to the most detailed (down).

DSS Generator
Computer software package that provides tools and capabilities that help a developer quickly and easily build a specific Decision Support System (cf., Sprague and Carlson, 1982, p. 11). Excel is an example of a DSS Generator. Many companies market tools for building DSS and EIS, see DSS Vendorlist.

DSS Development Tools
Software components (such as editors, code libraries, specific objects, visual interfaces) that facilitate the development of a specific DSS. New tools include object oriented languages like Java and C++.

 



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