Exam 2 Review October 30, 2014. Info. Systems in Organizations Decision Making

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Exam 2 Review October 30, 2014 Slide 2 Info. Systems in Organizations Decision Making Slide 3 3 IS & Hierarchical Organizational structure. Slide 4 4 Administrative Information Systems Transaction Processing Systems (TPS) Basic business system that serves the operational level (including analysts) in organizations Capture & process data generated during day-to-day activities Office Automation Systems (OAS) Systems designed to help office workers in doing their job. Decision Support Systems (DSS) Systems designed to support middle managers and business professionals during the decision-making process Executive Information Systems (EIS) or Executive Support Systems (ESS) Specialized DSS that help senior level executives make decisions. GDSS: computer-based systems that facilitate solving of unstructured problems by set of decision makers Slide 5 5 Organization & IS: another view Top Management Middle Management Lower Management Operational workers Office workers Knowledge workers Types of Information Systems: - Transaction Processing Systems - Office Automation Systems - Knowledge Worker Systems - Management Information Systems - Decision Support Systems - Executive Information Systems Q: What kind of IS are designed to provide help for decision makers? Questions Slide 6 6 Decision Making process Simons decision-making process model Intelligence Design Choice (Implementation) Newell, A., and Simon, H. A. (1972). Human problem solving Englewood Cliffs, Prentice-Hall, New Jersey. Herbert Simon (1955), A Behavioral Model of Rational Choice, Quarterly Journal of Economics, vol. 69, 99188 Slide 7 7 Intelligence Phase Scan the environment for a problem. Determine if decision- maker can solve the problem. Within their scope of influence? Fully define the problem by gathering more information about the problem. Scan Environment for problem to be solved or decision to be made Data source Organizational IS Problem ? END Problem within scope of influence? No Yes END No Gather more information about the problem Internal & External data Yes Slide 8 8 Design Phase Develop a model of the problem. Determine type of model. Verify model. Develop and analyze potential solutions. Develop a model of problem to be solved Verify that the model is accurate Develop potential solutions Slide 9 9 Choice Phase Select the solution to implement. More detailed analysis of selected solutions might be needed. Verify initial conditions. Analyze proposed solution against real-world constraints. Questions Slide 10 10 DSS structure Systems designed to help middle managers make decisions Major components Data management subsystem Internal and external data sources Analysis subsystem Typically mathematical in nature User interface How the people interact with the DSS Data visualization is the key Text Graphs Charts User Interface Analysis - Sensitivity Analysis - What-if Analysis - Goal-seeking Analysis -Data-driven tools -> Data mining -> OLAP* Data Management - Transactional Data - Data warehouse - Business partners data - Economic data * OLAP: OnLine Analytical Processing Slide 11 11 DSS Analysis Tools Simulation is used to examine proposed solutions and their impact Sensitivity analysis Determine how changes in one part of the model influence other parts of the model What-if analysis Manipulate variables to see what would happen in given scenarios Goal-seeking analysis Work backward from desired outcome Determine monthly payment given various interest rates. Works backward from a given monthly payment to determine various loans that would give that payment. Slide 12 12 Executive Information Systems Specialized DSS that supports senior level executives within the organization Most EISs offer the following capabilities: Consolidation involves the aggregation of information and features simple roll-ups to complex groupings of interrelated information Drill-down enables users to get details, and details of details, of information Slice-and-dice looks at information from different perspectives Digital dashboards are common features Slide 13 13 Artificial Intelligence (AI) systems Common categories of AI systems: 1.Expert system computerized advisory programs that imitate the reasoning processes of experts in solving difficult problems 2.Neural Network attempts to emulate the way the human brain works Analyses large quantities of info to establish patterns and characteristics in situations where logic or rules are unknown Uses Fuzzy logic a mathematical method of handling imprecise or subjective information 3.Genetic algorithm an artificial intelligent system that mimics the evolutionary, survival-of-the-fittest process to generate increasingly better solutions to a problem 4.Intelligent agent special-purposed knowledge-based information system that accomplishes specific tasks on behalf of its users Slide 14 14 Expert Systems Artificial Intelligence systems that codify human expertise in a computer system Main goal is to transfer knowledge from one person to another Wide range of subject areas Medical diagnosis Computer purchasing Knowledge engineer elicits the expertise from the expert and encodes it in the expert system Slide 15 15 Expert Systems Components Knowledge base: database of the expertise, often in IF THEN rules. Inference engine: derives recommendations from knowledge base and problem-specific data User interface: controls the dialog between the user and the system Explanation system: Explain the how and why of recommendations Knowledge base Domain Expert Knowledge Engineer Expertise Explanation System Inference Engine User Interface User System Engineer Encoded expertise IF family is albatross AND color is white THEN bird is laysan albatross. IF family is albatross AND color is dark THEN bird is black footed albatross Example of rules - Knowledge engineer codify the human experts expertise into the systems knowledge base. - System engineer is the IT professional who develop the user interface, the inference engine, and the explanation system. Slide 16 Database & Data Warehouse Slide 17 17 Basic Concepts of Database systems Table Two-dimensional structure composed of rows and columns Field Like a column in a spreadsheet Field name Like a column name in a spreadsheet Examples: AccountID, Customer, Type, Balance Field values Actual data for the field Record Set of fields that describe an entity (a person, an account, etc.) Primary key A field, or group of fields, that uniquely identifies a record AccountIDCustomerTypeBalance 660001John SmithChecking$120.00 660002Linda MartinSaving$9450.00 660003Paul GrahamChecking$3400.00 Accounts table Each table has: Fields Records 1 Primary key Slide 18 18 Basic Concepts in Data Management A Primary key could be a single field like in these tables AccountIDCustomerTypeBalance 660001John SmithChecking$120.00 660002Linda MartinSaving$9450.00 660003Paul GrahamChecking$3400.00 Primary key Primary key could be a composite key, i.e. multiple fields Slide 19 19 Traditional File Systems System of files that store groups of records used by a particular software application Simple but with a cost Inability to share data Inadequate security Difficulties in maintenance and expansion Allows data duplication (e.g. redundancy) Application 1 Program 1 File 1 File 2 File 3 Program 2 File 1 File 2 File 3 Application 2 Program 1 File 1 File 2 File 3 Program 2 File 1 File 2 File 3 Slide 20 20 Traditional File System Anomalies Insertion anomaly Data needs to be entered more than once if located in multiple file systems Modification anomaly Redundant data in separate file systems Inconsistent data in your system Deletion anomaly Failure to simultaneously delete all copies of redundant data Deletion of critical data Slide 21 Database Advantages Database advantages from a business perspective include Ease of data insertion Example: can insert a new address once; and the address is updated in all forms, reports, etc. Increased flexibility Handling changes quickly and easily Increased scalability and performance Scalability: how the DB can adapt to increased demand Reduced information redundancy & inconsistency Increased information integrity (quality) Cant delete a record if related info is used in other container Increased information security Slide 22 22 Types of DBMSs Desktop Designed to run on desktop computers Used by individuals or small businesses Requires little or no formal training Does not have all the capabilities of larger DBMSs Examples: Microsoft Access, FileMaker Desktop Server / Enterprise Handheld Slide 23 23 Types of DBMSs (Cont.) Server / Enterprise Designed for managing larger and complex databases by large organizations Typically operate in a client/server setup Either centralized or distributed Centralized all data on one server Easy to maintain Prone to run slowly when many simultaneous users No access if the one server goes down Distributed each location has part of the database Very complex database administration Usually faster than centralized If one server crashes, others can still continue to operate. Examples: Oracle Enterprise, DB2, Microsoft SQL Server Slide 24 24 Types of DBMSs (Cont.) Handheld Designed to run on handheld devices Less complex and have less capabilities than Desktop or Server DBMSs Example: Oracle Database Lite, IBMs DB2 Everywhere. Slide 25 25 DBMS Functions Create database structure (tables, relationships, schema, etc.) Transform data into information (reports,..) Provide user with different logical views of actual database content Provide security: password authentication, access control DBMSs control who can add, view, change, or delete data in the database ID Name Amt 01 John 23.00 02 Linda 3.00 03 Paul 53.00 Physical view ID Name 02 Linda Name Amt Paul 53.00 ID Name Amt 01 John 23.00 02 Linda 3.00 Logical views Slide 26 26 DBMS Functions (cont.) Allowing multi-user access with control Control concurrency of access to data Prevent one user from accessing data that has not been completely updated When selling tickets online, Ticketmaster allows you to hold a ticket for only 2 minutes to make your purchase decision, then the ticket is released to sell to someone else that is concurrency control Slide 27 27 Database Models Database model = a representation of the relationship between structures (e.g. tables) in a database Common database models Flat file model Relational model (the most common, today) Object-oriented database model Slide 28 28 Flat File Database model Stores data in basic table structures No relationship between tables Used on PDAs for address book Slide 29 29 Relational Database Model Multiple two-dimensional tables related by common fields Uses controlled redundancy to create fields that provide linkage relationships between tables in the database These fields are called foreign keys the secret to a relational database A foreign key is a field, or group of fields, in one table that is the primary key of another table Handles One-to-Many and One-to-One relationships Slide 30 30 Object-Oriented Database model Needed for multimedia applications that manage images, voice, videos, graphics, etc. Used in conjunction with Object-oriented programming languages Slower compared to relational DBMS for processing large volume of transactions Hybrid object-relational Databases are emerging Slide 31 Data Warehouse A logical collection of information gathered from many different operational databases Supports business analysis activities and decision-making tasks The primary purpose of a data warehouse is to aggregate information throughout an organization into a single repository for decision-making purposes 31 Slide 32 32 Data Warehouse Fundamentals Many organizations need internal, external, current, and historical data Data Warehouse are designed to, typically, store and manage data from operational transaction systems, Web site transactions, external sources, etc. Slide 33 Multidimensional Analysis Data mining the process of analyzing data to extract information not offered by the raw data alone Data-mining tools use a variety of techniques (fuzzy- logic, neural networks, intelligent agents) in order to find patterns and relationships in large volumes of data and infer rules that predict future behavior and guide decision making Other analytical tools: query tools, statistical tools, etc. used to Analyze data, determine relationships, and test hypotheses about the data 33 Slide 34 Data Warehouse Fundamentals Extraction, transformation, and loading (ETL) a process that extracts information from internal and external databases, transforms the information using a common set of enterprise definitions, and loads the information into a data warehouse. Slide 35 Information Cleansing or Scrubbing Organizations must maintain high-quality data in the data warehouse Information cleansing or scrubbing a process that weeds out and fixes or discards inconsistent, incorrect, or incomplete information first, occurs during ETL. Then, when the data is in the Data Warehouse using Information cleansing or scrubbing tools. 35 Slide 36 36 Data Mart Subset of data warehouses that is highly focused and isolated for a specific population of users Example: Marketing data mart, Sales data mart, etc. Slide 37 Database vs. Data Warehouse Databases contain information in a series of two-dimensional tables In a Data Warehouse and data mart, information is multidimensional, it contains layers of columns and rows 37 Date Product Country sum TV VCR PC 1Qtr 2Qtr 3Qtr 4Qtr U.S.A Canada Mexico sum Total annual sales of TV in U.S.A. Slide 38 Networking & Telecom Slide 39 Why Networking ? Resource sharing Sharing hardware (printers, processors, etc.) Sharing software (programs, data files) High reliability Can set automatic backup of programs and data at different locations Fault tolerance (if one server is down, others can provide service. If a disk fails, data available through mirror or RAID-3 disks) Possible cost savings Communication tool Internal email service Remote Access service 39 Slide 40 Computer Network An interconnection of computers and computing equipment using either wires or wireless transmission media over small or large geographical distances. Connect to GHI ABC DEF GHI JKL MNO Once connected to the network, the computer (or another device) becomes a network node 40 Slide 41 Network scope Local area network (LAN): computer network where the nodes are all in close proximity spanning a room, building, or campus Metropolitan area network (MAN): network that serves an area of 3 to 30 miles - approximately the area of a typical city. Wide area network (WAN): a large network that encompasses parts of states, multiple states, countries, and the world 41 Slide 42 Transmission Media Physical media Transmission media used to physically connect nodes to the network Transmits electrical or optical signals Could be copper wire or fiber optic cable Physical Wireless 42 Slide 43 Transmission Media (Continued) Twisted Pair CategoryUseSignalData rateDistanceProblem Category 1TelephoneAnalog/Digital