DSS Decision Support System.
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Transcript of DSS Decision Support System.
PRESENTATION: DECISION SUPPORT SYSTEM
Group Members:
Ahmad Raza Roll no. 007 M. Rashid Roll no. 067 Asad Bashir Roll no. 019 Irfan Khalid Roll no. 136
COMSATS INSTITUTE OF INFORMATION TECHNOLOGYLAHORE.
DECISION SUPPORT SYSTEM (DSS)
Decision Support System is a system that provides tools to managers to assist them in solving semi-structured and structured
problems.A DSS is not intended to make decisions
for managers.A DSS supports the human decision-
making process.
Systems that replace human decision making- rather than support it are called programmed decision systems.
EXAMPLE A writer, a selected group of journal and
text resources at a local library – and a strategy for using those resources – may serve as part of a decision support system.
Decision support systems are characterized by at least three properties:
They support semi-structured or un-structured decision making.
They are flexible enough to respond to the changing needs of decision makers.
They are easy to use.
DSS Goals and Applications
Structured decisions are those that are easily make from a given set of inputs.
E.g; issue a reminder notice if a bill is overdue or deciding to sell a stock under a given set of market conditions, can be programmed fairly easily.
Structured Decisions
Semi-structured and unstructured decisions are decisions for which information obtained from a computer system is only a portion of the total knowledge needed to make the decision.
Semi-structured and unstructured decisions
Figure: Steps in solving a problem with a DSS
Define and formulate problem
Frame problem into DSS model
Use Model to obtain results
Reformulate problem
CAPABILITIES OF DSS
A DSS provides support for decision maker at all management levels
It supports all phases of decision making process-intelligence-design and choice
It promotes learning.It is adaptable by the user over time to
deal with changing condition
PROPERTIES OF DECISION SUPPORT SYSTEM
Support for semi-structured and un-structured decision making.
Flexibility in specifying output requirements.
Ease of use and ease of development for non-professionals.
Fast response.
PROPERTIES OF DSS (CONT.)
Middle or top management focus. Use of models Focus on managerial effectiveness,
rather than efficiency.
MAJOR COMPONENTS OF A DSS
DSSSoftware
ModelBase
GraphicalInterface
UserDecisionMaker
Data BaseModels- Financial- Statistical analysis- Graphical- Project managment
COMPONENTS OF DSS
DATABASE: Current & Historical Data from Many Sources, as Required
MODEL BASE: Collection of Mathematical & Analytical Building Blocks
USER INTERFACE ;Communication between a DSS and user
USER: The person faced with the problem
A database is an organized collection of data for one or more multiple uses .
Databases consist of software-based "containers" that are structured to collect and store information so users can retrieve, add, update or remove such information in an automatic fashion
A graphical user interface (GUI) (sometimes pronounced gooey is a type of user interface item that allows people to interact with programs in more one ways
MODEL BASE Financial
e.g.: Cash Flow (discounted payback) Spreadsheet
Statistical Analysis
Graphical Project Management
Management Science
THE DATA MANAGEMENT SUBSYSTEM OF A DSS The data management subsystem allows the
user to create DSS databases by extracting data from other and, in some systems, databases that are external to the organization.
Figure; data management subsystem of a DSS.
External Databases
Electronic InformationServices
Databases of OtherStrategically linked companies
Personal, workgroup,And subunit databases
Finance
Marketing
Operations
Transactionprocessing
Personnel
DatabaseManagementcomponent
DSSdatabase
Data extraction
Database management• Data modification• Data retrieval• Report generation
DialogueManagemen
tsubsystem
ModelManagemen
tsubsystem
The model management software makes it possible for users to create, maintain, and use models needed to make decisions.
The model database may contain a wide variety of models, depending on the needs of decision makers.
Model Management Subsystem of a DSS
FIGURE: MODEL MANAGEMENT SUBSYSTEM OF A DSS
DataManagemen
tsubsystem
• Model creation• Model
modification• Model use• Model
maintenance
Dialogue managemen
tsubsystem
• Calculator functions
• Economic models• Financial models• Forecasting
models• Management-
science ….models• Marketing models• Operations models• Sensitivity analysis• Simulation models• Statistical models• Transportation/
logistics …models
Model management software
THE DIALOGUE MANAGEMENT SUBSYSTEM
The dialogue management system provides users with a flexible, interactive interface for input, processing and output.
FIGURE; DIALOGUE MANAGEMENT SUBSYSTEM
Model management
subsystem
DataManagemen
tsubsystem
DeviceSuppo
rtSoftwar
e
Input modules that support:_________________________________________
• Command language• Direct data entry;
o Keyboardo Lightpeno Mouseo Pen=based tableto Scanner, and so on
• Graphical user interface• Natural language
interface• On-screen menus• On-screen templates• Programming language
interface
Output modulesThat support;
-------------------------------• Graphics• On-screen display• Multidemensional
dispalys• On-screen windows• Report generation• Printers, plotters
etc.
PUTTING A DSS AT WORK
The tasks commonly performed by decision support systems are; Information retrieval Data reconfiguration Calculator activities Analysis
INFORMATION RETRIEVAL
Information retrieval in a DSS environment refers to the act of extracting information from a database, or from data files for the purpose of making decision.
SELECTION AND PROJECTION
Two common types of retrieval are;- Selection- Projection
Selection: Selection involves separating out records that have specific charabteristics.
e.g. identifying all males overgage 64 in employee file or database.
Projection: obtaining only certain fields of data.
e.g. extracting all names and phone numbers from an employee file or database.
FIGURE: DATA RECONFIGURATIONState City NamePunjab Multan M. RashidPunjab Lahore Irfan KhalidPunjab jranwla Asad BashirSindh Karachi Ahmad RzaBlchstan Kohlu Zahid Ali
Name City State Zip
M. Rashid Multan Punjab 52000Irfan Khalid Lahore Punjab 54000Asad BashirJranwla Punjab 50000Ahmad Raza Karachi Sindh
42000Zahid Ali Kohlu Blchstan 65000
Name City State
Ahmad Raza Karachi SindhAsad Bashir Jranwla PunjabIrfan Khalid Lahore PunjabM. Rashid Multan PunjabZahid Ali KohluBlchstan
Name City State
M. Rashid Multan PunjabIrfan Khalid Lahore PunjabAsad Bashir Jranwla PunjabAhmad Raza Karachi SindhZahid Ali KohluBlchstan
(b) Exchanging fields (columns)
(c) Joining (with zip code data)
(d) Presentation graphics(pie chart by state)
(a) Sorting by name
Original data:
Punjab(60%)
Sindh(20%)
Blchstan(20%)
CALCULATOR ACTIVITIES
Functions- Arithmetic and Statistical Functions i.e. SUM, AVG, LOG etc.
- Financial Functions PV, FV, NPV, PMT etc.
- Conditional Functions IF, CHOOSE etc.
- Data Functions TODAY, DATE etc.
ANALYSIS Four widely used types of DSS analysis
tools:Statistical ToolsOptimizing ToolsWhat-if Analysis Intelligence routines.
The DSS development process in many instances, after decision-making needs are identified and an initial prototype developed, several evaluation/ modification iterations may be needed before the DSS is ready for use.
DSS development tools:=> Spreadsheets=> User Interface=> Command Interfaces=> Templates=> Physical Modification
DSS Development
Figure: DSS Development Process
Determination of decision-making requirements
Developmetn of Initial DSS prototype
Evaluation of Prototype/DSS
Yes
Usable DSS
Completion and documentation of DSS
Modification of Prototype/DSS
Are Decision-making
requirements satisfied?
NO
Evaluation/ modification loop
Determination of decision-making requirements
Developmetn of Initial DSS prototype
Evaluation of Prototype/DSS
Yes
Usable DSS
Completion and documentation of DSS
Modification of Prototype/DSS
Are Decision-making
requirements satisfied?
NO
Determination of decision-making requirements
Developmetn of Initial DSS prototype
Evaluation of Prototype/DSS
Yes
Usable DSS
Completion and documentation of DSS
Modification of Prototype/DSS
Are Decision-making
requirements satisfied?
NO
Evaluation/ modification loop
A contract negotication DSS An Oil Executive’s DSS An Environmental DSS
DSS Examples
Group Decision Support Systems
Group of managers could also use a DSS as well on a common task or issue
To facilitate this a GDSS (Group Decision Support System) application is provided to multiple users on various computer and on multiple networks
Is the requirement in the organization that believe in team-based working environment
Characteristics of a GDSS (1)
• Special design: – Effective communication
– Group decision making
• Ease of use
• Flexibility– Accommodate different perspectives
• Anonymous input– Individuals’ names are not exposed
• Parallel communication
Characteristics of a GDSS (2)
• Decision-making support– Delphi approach: Decision makers are scattered
around the globe– Brainstorming: Say things as you think---think out
loud– Group consensus approach: The group reaches a
unanimous decision (everybody agrees)– Nominal group technique: Voting
• Reduction of negative group behavior– A trained meeting facilitator to help with sidetracking
• Automated record keeping
Examples of GDSS Software
• Lotus Notes– Store, manipulate, distribute memos
• Microsoft Exchange– Keep individual schedules
– Decide on meeting times
• NetDocuments Enterprise– Two people can review the same document
together
GDSS Alternatives