lecture 6: dssmit.wu.ac.th/mit/images/editor/files/l6 - dss.pdfdecision support systems • systems...
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Lecture 6: DSS
ITM-761 Business Intelligence
ดร. สลลิ บญุพราหมณ์
topics
• DSS • Characteristics / capabilities • Components • DSS Classifications
• GDSS • Definition • GDSS architecture • Components of a GDSS and GDSS Software • GDSS Alternatives
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ความเจรญิของประเทศชาต ิเป็นความเจรญิสว่นรวม ซึง่เกดิจากผลงานหรอืผลของการกระทําของคนทัง้ชาต ิถอืไดว้า่ทกุคนแบง่หนา้ทีก่นัทําประโยชนใ์หแ้กช่าต ิตามความถนัดและความสามารถ และเกือ้กลูกนัและกนั ไมม่ผีูใ้ดจะอยูไ่ดแ้ละทํางานใหแ้กป่ระเทศชาตไิดโ้ดยลําพังตนเอง
คดัจากพระบรมราโชวาทของ พระบาทสมเด็จพระเจา้อยูห่วั
ในพธิพีระราชทานปรญิญาบตัรของจฬุาลงกรณ์มหาวทิยาลยั 10 กรกฎาคม 2513
Decision Support Systems
• Systems designed to support managerial decision-making in
unstructured problems
• More recently, emphasis has shifted to inputs from outputs
• Mechanism for interaction between user and components
• Usually built to support solution or evaluate opportunities
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• A DSS is a methodology that supports decision-making.
• It is
• Flexible
• Adaptive
• Interactive
• GUI-based
• Iterative
• Employs modeling 5
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Components of DSS
• Subsystems:
• Data management
• Managed by DBMS
• Model management
• Managed by MBMS
• User interface
• Knowledge management and organizational knowledge
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Data Management Subsystem
• Components:
• Database
• Database management system
• Data directory
• Query facility
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Database
• Interrelated data extracted from various sources, stored for use by the organization, and queried • Internal data, usually from TPS • External data from government agencies, trade
associations, market research firms, forecasting firms • Private data or guidelines used by decision-makers
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Database Management System
• Extracts data • Manages data and their relationships • Updates (add, delete, edit, change) • Retrieves data (accesses it) • Queries and manipulates data • Employs data dictionary
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Data Directory
• Catalog of all data • Contains data definitions • Answers questions about the availability of data items • Source • Meaning • Allows for additions, removals, and alterations
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Model Management Subsystem
• Components:
• Model base
• Model base management system
• Modeling language
• Model directory
• Model execution, integration, and command processor
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Models
• Strategic
• Supports top management decisions
• Tactical
• Used primarily by middle management to allocate resources
• Operational
• Supports daily activities
• Analytical
• Used to perform analysis of data 15
Model Base Management System
• Functions:
• Model creation
• Model updates
• Model data manipulation
• Generation of new routines
• Model directory:
• Catalog of models
• Definitions
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Model Management Activities
• Model execution • Controls running of model
• Model command processor • Receives model instructions from user interface • Routes instructions to MBMS or module execution or
integration functions • Model integration
• Combines several models’ operations
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User Interface System
Knowledge-based system
Data management and DBMS
Model management and MBMS
User Interface Management System (UIMS)
Natural Language Processor Input Action Languages
Output Display Language
Users Printers, Plotters
PC Display
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View of the User Interface
User Interface Management System
• GUI • Natural language processor • Interacts with model management and data
management subsystems • Examples
• Speech recognition • Display panel • Tactile interfaces • Gesture interface 19
Knowledge-Based Management System
• Expert or intelligent agent system component • Complex problem solving • Enhances operations of other components • May consist of several systems • Often text-oriented DSS
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DSS Hardware
• De facto standard • Web server with DBMS:
• Operates using browser • Data stored in variety of databases • Can be mainframe, server, workstation, or PC • Any network type • Access for mobile devices
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DSS Classifications
• Alter • Extent to which outputs can directly support or
determine the decision • Data oriented or model oriented
• Holsapple and Whinston
• Text oriented, database oriented, spreadsheet oriented, solver oriented, rule oriented, or compound Intelligent
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(ad hoc analysis)
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DSS Classifications • Donovan and Madnick
• Institutional • Problems of recurring nature
• Ad hoc • Problems that are not anticipated or are not
repetitive
• Hackathorn and Keen
• Personal support, group support, or organizational support
DSS Classifications
• GSS v. Individual DSS • Decisions made by entire group or by lone decision
maker • Custom made v. vendor ready made
• Generic DSS may be modified for use • Database, models, interface, support are built in • Addresses repeatable industry problems • Reduces costs
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Web and DSS
• Data collection • Communications • Collaborations • Download capabilities • Run on Web servers • Simplifies integration problems • Increased usability features
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Group Decision Support System
• Supports a group of people making a decision • Variation
• Multi-user, networked • Same or different location • Same or different time
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Benefits of working in group
• Easier to understand problem • More people accountable for decisions • Better at catching errors • Synergistic effects • More people committed to implementation • Reduces sources of resistance to implementation
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Traps and difficulties
• Members of a group may have different • Objectives • Information • Competencies
• A group may have difficulty • Communicating information between members • Coordinating implementation of policies
• Interpersonal dynamics affects outcomes • Groupthink • Domination by strong personalities • Fear of expressing opinion
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• At the First International Conference on Decision Support Systems in 1981, Peter G. W. Keen pointed out that the fundamental model of DSS—the lonely decision maker is truly in rare cases.
• In real organizations, be they public or private, Japanese, European, or American, most decisions are taken only after extensive consultation.
Evolution
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• A DSS is usually designed to be used by a particular decision-maker. That is, a decision is made basically from the input provided by one particular person.
• Group DSSs are designed to be used by more than one
decision maker. These systems are useful for committees, review panels, board meetings, task forces, and decision making sessions that require the input of several decision makers.
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Definition
• “ A GDSS consists of a set of software, hardware, and language components and procedures that support a group of people engaged in a decision-related meeting.” (Huber, 1982)
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• DeSanctis and Gullupe define a GDSS as an interactive, computer-based system that facilitates solution of unstructured and semistructured problems by a set of decision-makers working as a group.
• This definition is very similar to the definition of DSS. The only difference is the existence of the group versus individual decision makers. By this definition, the components of a GDSS, hardware, software, people, and procedures, are basically the same as the components of DSS in general.
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• An important point to note is that the group using the GDSS may not make the ultimate decision.
• It may be creating and/or reviewing alternatives to be submitted as a short list to the next level in the organizational hierarchy.
• GDSS can be viewed as subsuming conventional DSS within it. That is, the concepts of model base, database, and human interface all apply. Thus, as group size shrinks to one, a GDSS reduces to a DSS.
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Conversely, in moving from a DSS to GDSS, some new requirements are introduced:
• The addition of communications capabilities • Enhancement of the model base to provide voting,
ranking, rating, and so on, for developing consensus. • Greater system reliability • Enhance physical facilities • Increased setup before use of the system
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To be more specific, consider the hardware/software components of a GDSS.
The software components include: • Database capabilities • Modeling capabilities • Dialog management with multiple-user access • Specialized application program to facilitate group
access
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GDSS architecture
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The hardware components of GDSS include: • General purpose I/O devices (terminal, CRT, voice I/O) • Central processor • Common viewing screen (for the group) or individual
monitor (for each participant) • A network system linking the different
sited/participants to each other
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• Although most group decision meetings are face-to-face, technology is starting to be applied to make it possible for participants to be separated in space and/or time.
• These technologically enhanced meetings include
computer conferences and audio and video teleconferences.
• DeSanctis and Gallupe discuss the four combinations of proximity and separation in space and in time.
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Components of a GDSS and GDSS Software
• Database • Model base • Dialogue manager • Communication capability • Special software (also called GroupWare)
• For example Lotus Notes • people located around the world work on the same
project, documents, and files, efficiently and at the same time
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GDSS capabilities
Word processing and text manipulation • Group members need access to and support from word
processing programs and text manipulation packages. • These packages must go beyond traditional word
processing to provide multiple group members access to common files.
• This access allows several members in a group setting to work on common documents at the same time, including reports, forecasts, and proposals.
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Database and file manipulation • Database capabilities are often a requirement in group
decision making setting. • In some cases, these capabilities allow decision makers
to obtain information needed to make effective group decisions.
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Worksheet or spreadsheet abilities • If group decision support systems become more
important in business, worksheet packages may start to incorporate group features.
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Graphics packages • Graphical packages should allow the users to develop
the attractive and informative illustrations, drawing, and pictures that can be directly incorporated into reports and other documents.
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Decision making aids • Includes computer programs that can assist in listing
alternatives, analyzing potential solutions, incorporating subjective information into decisions, and ranking alternatives using a variety of methods.
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Communications facilities • LAN and telecommunication.
Help facilities • GDSS were developed in response to growing concern
over the quality and effectiveness of meetings.
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• Special design • A number of specialized software packages called
groupware support all aspects of group decision making. • These packages allow two or more individuals in the
group to effectively work together to use word processing, database, spreadsheet, and related software packages.
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• In some cases, the software packages are modified to allow access by a number of group numbers.
• Ease of use
• Specific and general support
• งานวจัิยทีศ่กึษาการใชง้านของ Groupware เป็นงานในสาขา Computer-supported cooperative work(CSCW)
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• Groupware = Computer-based systems that support groups of people engaged in a common task (or goal) and that provide an interface to a shared environment.
• GDSS should provide solutions for both specific and general problems.
• Generalized software packages can assist in many group decision-making settings.
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• Some group situations, however, call for highly specific, tailor-made GDSS approaches. These settings may require development of specialized software procedures.
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Suppression of negative group behavior
• Dominant individuals can take over the discussion, which can prevent other members of the group from presenting creative alternatives.
• Many GDSS designers are developing software and
hardware systems that will reduce the types of problems.
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Support of positive group behavior
• For example, the Delphi approach allows group decision making in which decision makers are geographically dispersed throughout the country or the world.
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GDSS Alternatives
Local area decision network
Wide area decision network
Decision room Teleconferencing
Location of group members
close distant
high
low Deci
sion
freq
uenc
y
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1. Decision room
• In the decision room GDSS, decision-makers sit around a horseshoe-shaped desk facing a large screen.
• Each participant has access to a terminal; for individual participant input, but at the same time can see the large screen.
• The large screen is used to summarize the input from individual participants.
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• The motivation for creating a decision room comes from the observation that in almost all organization office automation has resulted in terminals being ubiquitous in work areas.
• However, as soon as one-steps into the conference room, technology is a telephone and high technology is a speakerphone. The personal and online computer capabilities used routinely elsewhere are not available.
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• Input of these terminals is by keyboard, mouse, touch-screen, or some combination of these.
• Participants can do “private work” at their individual displays.
• One member of the group (as a “chauffeur”) operates the software needed to create the “public” display that can be seen by everyone.
• In some rooms, multiple public screens are provided where one screen is used for the current discussion and the others for reference or slowly changing information.
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• Because decision rooms are designed for senior managers, they tend to have an “executive feel” to them.
• Even the experimental laboratories are being created with plush carpeting and quality furnishings. 59
2. Local decision network (LDN)
• In LDN, the participants are dispersed in a limited geographical area. They can participate from their own offices and express their views.
• This architecture includes a central processor with dedicated software for storing the results.
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3. Teleconferencing
Video camera
Terminal
Public screen
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• Teleconferencing enables decision-makers in scattered geographic regions to see and hear each other as they participate in group decision-making.
Faculty of Applied Sciences, University of Liege
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4. Remote decision making
• Remote decision making advocates “uninterrupted communication” on a regular basis among a fixed number of decision makers in a geographically dispersed organization.
• In this type of architecture there is no need to schedule meeting in advance as in teleconferencing.
• A participant may send his or her input to central database (electronic mailbox); then the other participants respond to this input.
• Eventually a decision is made by consensus. 63
GDSS in use
• Electronic meeting system (Same time, same place) • Electronic meeting room • Electronic boardroom • War room
• Workflow system (Different time, different place) • GDSS can support
• Problem formulation • Analysis • Choice • implementation
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Role of GDSS
• On-line entry and solution of decision model • Bookkeeping • Anonymous discussion and sharing of ideas
• Required networked system • Encourages quiet individuals to contribute to
discussion • Discourages intimidation and domination of
discussion • Automated vote tally and summary of results
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Potential benefits of GDSS
• More thorough exploration of values • Better sharing of information • More creative option generation • More systematic option evaluation • Increased communication • Increased participation • Increased group cohesion • Increased acceptance of group decision
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