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Explore how organizations function as systems, the impact of organizational culture on information system design, and the levels of management required for effective IT solutions. Learn about system interrelations, feedback mechanisms, and the importance of taking a systems perspective.
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IS 334information systems analysis and design 1437/1438 Semester 2 Chapter-2 Understanding and Modeling Organizational System Information Systems Department
Learning Objectives • Understand that organizations and their members are systems and that analysts need to take a systems perspective. • Depict systems graphically using context-level data flow diagrams, and entity-relationship models, use cases. • Recognize that different levels of management require different systems. • Comprehend that organizational culture impacts the design of information systems. Information Systems Department
Major Topics • Organizations as systems • Depicting systems graphically • Data flow diagram • Entity-relationship model • Use case modeling • Levels of management • Organizational culture
Organization • To analyze and design appropriate information systems, systems analysts need to comprehend organizations through the three main forces which interacting to shape the organization: • Levels of Management • Design of Organizations • Organizational Cultures
Organizations As Systems • Conceptualized as systems designed to accomplish predetermined goals and objectives • Organizations are composed of smaller • Interrelated systems: departments, units, and divisions,... • Interdependent subsystems Serving specialized functions: accounting, marking, production, data process and management.
Interrelatedness and Independence of Systems • All systems and subsystems are interrelated and interdependent • All systems process inputs from their environments • All systems are contained by boundaries separating them from their environments • System feedback is one form of system control. Organization use planning and control to manage their resources effectively. • An ideal system self-corrects or self-regulates itself
Figure 2.1 System outputs serve as feedback that compares performance with goals System Feedback
Organizational Environments Anything external to an organization’s boundaries is considered to be an environment. • Community environment • Organization Size and Physical location • Organization’s Demographic profile (education, income) • Economic environment • influenced by Market factors • Competition • Political environment • organization is controlled through state and local governments • Legal environment • Issuing federal, state, regional, local laws and guidelines.
Open and Closed Systems • A key aspect of a system for building is the system’s relationship with its environment. • There is no such thing as an absolutely open or completely closed organization. • Systems are described as either: • Open system: interacts freely with its environment, taking input and returning output. (such as creative, art departments, library, information system are characterized as open.) • Free-flowing information within the organization. As environment changes an open system must adapt to change . • Output from one system becomes input to another. • Closed system:is cut off from its environment and does not interact with it. (such as defense department unit assigned to work on top-secret defense planning affecting national security.) • Restricted access to information • Limited by numerous rules. • Information on a need to know basis. Information Systems Department
Virtual Organizations and Virtual Teams • A virtual organization has parts of the organization in different physical locations • Computer networks and communications technology are used to bring virtual teams together to work on projects
Virtual Organizations and Virtual Teams (cont.) • Benefits of Virtual Organizations and Teams • Possibility of reducing costs of physical facilities • More rapid response to customer needs • Helping virtual employees to fulfill their familial obligations to growing children or aging parents
Taking a Systems Perspective • Taking system perspective allows system analyst to understand businesses before they begin their tasks • It is important that members of subsystems realize that they are interrelated with other subsystems • Problems occur when each manager thinks that his/her department is the most important • Bigger problems may occur when that manager rises through the ranks
Taking a Systems Perspective (cont.) Neither subsystem can accomplish its goals without the other.
Taking a Systems Perspective (cont.) • If a production manager is promoted but continues to stress production scheduling and performance of line workers, the broader aspects of forecasting and policy making may suffer. • This tendency is a danger in all sorts of businesses. Their tunnel vision often creates problems for the systems analyst trying to separate actual informational requirements from desires for a particular kind of information.
Example: A fast food restaurant ‘Hoosier Burger’ as a system. • Physicalsubsystems: kitchen, dining room, counter, storage and office. • The subsystems are interrelated and work together to prepare food and deliver it to customers. • The boundary of Hoosier Burger is represented by its physical walls. • One purpose is to make a profit for its owners. • Environment: customers, food distributors, bank, local labor supply and neighbourhood fast food competitors. • Interface: at the counter where customers place orders and another at the back door where food and supplies are delivered. Still another is the telephone manager use regularly to talk with bankers and food distributors. 7. Input: food, labor and cash. 8. Output: prepare food , bank deposits and trash. 9. Constraints: the restaurant in the foods it may offer for sale, how much money it can make on any given day, Rules governing food storage.
Enterprise Resource Planning • Enterprise Resource Planning (ERP) describes an integrated organizational information system • Software that helps the flow of information between the functional areas within the organization
Depicting Systems Graphically • A system or subsystem may be graphically depicted in several ways. The various graphical models show the boundaries of the system and the information used in the system are: • Context-level data flow diagrams • Entity-relationship model • Use Case Modeling
Context-Level Data Flow Diagrams • A context-level data flow diagram is an important tool for showing data flowing into and out of the system and the processing of the data. • It provides an overview of the setting or environment the system exists within: which entities supply and receive data/information. • It shows how data moves through an information system. DFD represent a logical model that shows what the system does, not how it does it.
Figure 2.4 The basic symbols of a data flow diagram Context-Level Data Flow Diagrams(cont.)
Entity-Relationship Model (E-R Diagram) • Entity-relationship Diagrams help the analyst understand the organizational system and the data stored by the organization. • Focus is on the entities and their relationships within the organizational system
Entity-Relationship Model (E-R Diagram) • E-R Diagram consists of: • Entity: Anything about which we wish to maintaininformation, may be a person, a place , a thing, a concept or an event. • Relationship: is the association that describes the interaction among the entities. (One-to-one, One-to-many, Many-to-many) • Attribute: Property or characteristic of an entity type. Data attributes may be added to the diagram
Figure 2.8 Examples of different types of relationships in E-R diagrams
Use Case Modeling • Describes what a system does without describing how the system does it; that is, it is a logical model of the system
Use Case Diagram (cont.) Use Case Diagram consists of: • Actor • Refers to a particular role of a user of the system • Similar to external entities; they exist outside of the system • Use case symbols • An oval indicating the task of the use case • Connecting lines • Arrows and lines used to diagram behavioral relationships
Actor • Divided into two groups • Primary actors • Supply data or receive information from the system • Provide details on what the use case should do • Supporting actors • Help to keep the system running or provide help • The people who run the help desk, the analysts, programmers, and so on
Use Case Relations • Behavioral relationships • Communicates • Used to connect an actor to a use case • Includes • Describes the situation in which a use case contains behavior that is common to more than one use case
Use Case Relations • Behavioral relationships (Continued) • Extends • Describes the situation in which one use case possesses the behavior that allows the new case to handle a variation or exception from the basic use case • Generalizes • Implies that one thing is more typical than the other thing
Levels of Management • The three levels of managerial control are: • Operations management. • Middle management. • Strategic management • Each level carries its own responsibilities and all work toward achieving organizational goals and objectives in their own ways. Figure 2.18Management in organizations exists on three horizontal levels: operational control, managerial planning and control, and strategic management
1. Operations Management • Make decisions using predetermined rules that have predictable outcomes • Oversee the operating details of the organization • Make short-term planning and control decisions about resources and organizational objectives
2. Middle Management • Make short-term planning and control decisions about how resources best be allocated to meet organizational objectives • Decisions may be partly operational and partly strategic
3. Strategic Management • Look outward from the organization to the future • Make decisions that will guide middle and operations managers • Work in highly uncertain decision-making environment • Define the organization as a whole
Managerial Levels • Each of the three levels of management have: • Different organization structure • Leadership style • Technological considerations • Organization culture • Human interaction • All carry implications for the analysis and design of information systems
Organizational Culture • Organizational culture is a system of shared assumptions, values, and beliefs, which governs how people behave in organizations. • Organizations have cultures and subcultures • Learn from verbal and nonverbal symbolism
Verbal Symbolism • Myths • Metaphors • Visions • Humor
Nonverbal Symbolism • Shared artifacts • Trophies, etc. • Rites and rituals • Promotions • Birthdays, etc. • Clothing worn • Office placement and decorations
Summary • Organizational fundamentals • Organizations as systems • Levels of management • Organizational culture • Graphical representation of systems • DFD • ERD • Use case diagrams and scenarios
Summary (Continued) • Levels of managerial control • Operational • Middle management • Strategic • Organizational culture