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Decision Support System ICS425. Building Data and Document-Driven DSS. This unit will cover…. What is Data-driven DSS and Document-driven DSS? Comparing two of them? Data-driven subcategories? DSS Data vs. Operating Data. Data-driven DSS architecture. Implementation of Data-driven DSS.
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Decision Support System ICS425 Building Data and Document-Driven DSS
This unit will cover… • What is Data-driven DSS and Document-driven DSS? • Comparing two of them? • Data-driven subcategories? • DSS Data vs. Operating Data. • Data-driven DSS architecture. • Implementation of Data-driven DSS
Introduction • In recent years, most large companies + many other large organizations have implemented; - database system => data warehouse - document management - OLAP (On-line analytical processing) - BI (Business Intelligence) or created EIS (Executive Information Systems)
Data-driven DSS • What is it? • It’s an interactive computer-based system that helps a decision maker use very large database of business data and, in some systems, data about the external environment of a company. • Data-driven DSS help managers retrieve, display, and analyze historical data
Document-driven DSS • “a variety of storage and processing technologies to provide complete document retrieval and analysis” • Knowledge management, Web are used to build document-driven DSS.
Data-driven vs. Document-driven DSS Different issues • Document-driven DSS help managers process “soft” or qualitative information. • Data-driven DSS help managers process “hard” or numeric data
Data-driven vs. Document-driven DSS (Sullivan, 2001).. “Data-driven help managers analyze, display and manipulate large structured data sets that contain numeric and short character strings” WHILE “Document-driven DSS analyze, display, and manipulate text including logical units of text, called documents”
Data-driven vs. Document-driven DSS • If you think about analysis tools used for decision support…. @ Data-driven DSS use quantitative and statistical tools for ordering, summarizing and evaluating the specific contents of a subject-oriented data warehouse @ Document-driven DSS use natural language and statistical tools for extracting, categorizing, indexing, and summarizing subject-oriented document warehouse.
Data-driven vs. Document-driven DSS Similar issues • Use database. • Require the definition of metadata and the cleaning, extraction and loading of data into an appropriate data management system using an organizing framework. • Understanding the decision support and information needs of the targeted users.
Data-Driven DSS Subcategories Generally, the broad category of data-driven DSS includes tools to help users “drill down” for more detailed information, “drill up” to see a broader, more summarized view, and “slice and dice” to change the data dimensions they are viewing. • “drilling” and “ slicing and dicing” are presented in tables and charts
Data-Driven DSS Subcategories There are 4 subcategories; • Data Warehouse • On-Line Analytical Processing (OLAP) • Executive Information System (EIS) • Geographic Information Systems and Spatial DSS
Data Warehouses • “A specific database designed and populated to provide decision support in an organization” (Gray & Watson, 1998) • Contain large amounts of data – 500 megabytes or more. • “A data warehouse is a subject-oriented, integrated, time-variant, nonvolatile collection of data in support of management’s decision making process” (Bill Inmon, 1995)
Data Warehouses 4 characteristics of a data warehouse (Inmon, 1995) • Subject-oriented: focuses on subjects related to business or organizational activity like customers, employees and suppliers • Integrated: the data from various databases is stored in a consistent format through use of naming conventions, domain constraints, physical attributes and measurement.
Data Warehouses 3. Time- variant: refers to associating data with specific points in time. 4. Nonvolatile: the data does not change once it is in the warehouse and stored for decision support
Data Warehouses • From Ralph Kimball (1996), “a data warehouse is a copy of transaction data specifically structured for query and analysis”
Data Warehouses DATA MART => is a more focused or a single subject data warehouse. e.g. some companies build a customer data mart rather than a multi-subject data warehouse. Such a focused data mart would have all of the business information about a company’s customers.
OLAP • On-Line Analytical Processing • Refers to software for manipulating multidimensional data • OLAP software provides fast, consistent, interactive access to shared. Multidimensional information (Nigel Pendse, OLAPReport.com) These characteristics are FASMI test!!
OLAP • F = Fast: the system delivers most responses to users within about five seconds • A = Analysis: the system can cope with any business logic and statistical analysis that is relevant for the application and the user
OLAP • S = Shared: the software has security capabilities needed for sharing data among users. • M = Multidimensional: an essential requirement. An OLAP system must provide a multidimensional, conceptual view of the data. • I = Information: the software can support all pf the data and derived information that managers need.
OLAP • Jay Tyo (1996) divided OLAP tools into 5 broad types • stand-alone desktop OLAP tools • Integrated desktop tools • Relational OLAP tools • Personal multidimensional databases • Other OLAP tools # Business Intelligence (BI) is sometimes used interchangeably with OLAP an other synonyms for DSS#
EIS • “Computerized systems intended to provide current and appropriate information to support executive decision making for managers” (Watson, Rainer, and Houdeshel, 1992)
EIS • What the differences of EIS from traditional information systems? • EIS are specifically tailored to an executive’s information needs • EIS are able to access data about specific issues and problems as well as aggregate reports
EIS 3. EIS provide extensive on-line analysis tools including trend analysis, exception reporting, pivot tables, and “drill-down” capacity 4. EIS access a broad range of internal and external data
EIS So… • EIS are intended to help senior executives find problems, identify opportunities, identify trends, and make fact-based decisions. • EIS report key business results to managers
GIS & Spatial DSS • GIS : a support system that represents data by using maps. • Spatial DSS help a manager access, display, and analyze data that have geographic content and meaning • E.g. of Spatial DSS => systems for crime analysis and mapping, customer demographic analyzes, and potential voting patterns analysis
DSS Data vs Operating Data • DSS data is data about transactions and business occurrences • It is created to provide tactical and strategic business meaning to operating data and relevant external data • While, operating data is a detailed record of a company’s daily business transactions
1. Data Structure • Normalization is the process of reducing a complex data structure into its simplest, most stable, structure. • The process involves removing redundant attributes, keys, and relationships from a conceptual data model. • DSS Data are generally stored in many fewer tables and integrated from multiple operating databases, and are sometimes aggregated and summarized in the database to support predefined decision support needs
DSS Data vs Operating Data Different data components of data warehouse often include: • Metadata • Current detail data • Older detail data • Lightly summarized data • Highly summarized data
2. Time Span • Operating data shows the current status of business transactions • DSS data are a snapshot of the operating data at given points in time • Therefore DSS data are an historic time series of operating data
3. Summarization • DSS Data can be summarized in the DSS data store, and disaggregated data can be summarized by analytical processing software • Operating data is not summarized within a transaction database
4. Data Volatility • Operating data changed when a new transaction occurs • But DSS data has no on-line updating and changing of data. Data can be added in batches so the DSS data is non-volatile
5.Data Dimension • DSS data are always related in many different ways (from manager’s and DSS analyst’s point of view) • Operating data has only one dimension
6. Metadata • It is important to develop and maintain metadata about the DSS data(coz DSS data may come from many sources -> creating data dictionaries for transaction systems is especially important) • Thus, integration of DSS data -> data dictionary provides a reference about how data has been combined from various sources.
6. Metadata • Metadata is a guide to mapping data as it is transformed from the operating environment to the data warehouse environment, and it serves as a guide to the algorithm used for summarization of current detailed data.
Data-driven DSS architecture • DSS designers -> begin-> researching other data-driven DSS to identify a data model and an appropriate DSS architecture • Need to understand a typical data-driven DSS’s components and interfaces, how it fits into the typical organization, and what the typical reasons are for success or failure
Data-driven DSS architecture • Starting-> examine software architecture • At least components -> provide data structures for a data store, guidelines for a data extraction and filtering management tool, interfaces for a query tool, and some predefined charts and tables for use with a data analysis and presentation tool.
Data-driven DSS architecture • The components: - data store component: database, database management system, multidimensional database management system - data extraction & filtering component: used to extract and validate the data taken from the operational databases and the external data sources
Data-driven DSS architecture - end user analysis & presentation tool: helps a manager perform calculations and select the most appropriate presentation format
Implementing a Data-driven DSS • Subject to numerous constraints; 1. available funding 2. a function of management’s view of the role played by an IS department and of management information and DSS requirements 3. corporate culture conflicts @note: DSS data store is not a static database
Implementing a Data-driven DSS • Decision support infrastructure includes @ hardware @software @people @procedures • Data store is a critical component, but it’s not the only important componentss
Implementing a Data-driven DSS • Technical aspects of creating a new database must be addressed • DSS analyst must support the data analysis needs of decision makers • Data-driven DSS must provide required analysis capabilities with acceptable query performance
Implementing a Data-driven DSS • Traditional database design procedures must be adapted to fit the requirements of building a large DSS data store • Data is derived from transaction databases, so a DSS analyst must understand the transaction database designs
A general development process • Has 2 general approached: Systems Development Life Cycle and Rapid Prototyping • It has 5 steps of the decision-oriented design and development process !!
A general development process Step3: Load/Test Step2: Design/Map Step4: Build/Test Decision-Oriented Design and Development Process Step1: Diagnosis Step5: Rollout
A general development process • Step 1: Initial Data Gathering or Diagnosis - identifying and interviewing key future DSS users - defining the main subjects of the DSS - identifying the transaction data model - defining ownership of data - assessing frequency of use and updates - defining end user interface requirements - defining any outputs and representations
A general development process • Step 2: Designing and Mapping the Data Store - design the Star Schema - identify facts, dimensions, and attributes - in multidimensional database-> key variables and dimensions need to defined
A general development process • Step 3: Loading and Testing Data - preparing to load data - defining initial data to load - defining update processes - define transformation of the transaction data and any external data (map from the operational transaction data, integrate and transform the data) - analysts load, index and validate the data - verify metadata and data cubes or Star Schemas
A general development process • Step 4: Building and Testing the Data-Driven DSS - create menus - develop output formats, build anticipated queries - test interfaces and results - optimize for speed and accuracy - engage in end user prototyping and testing - provide end user training in a development environment
A general development process • Step 5: Rollout and Feedback - deploying the DSS - providing additional training - getting user feedback - maintaining the system - expanding and improving the DSS