Chap02-DFD

Chapter Overview

  • Understanding Organizational Style and Its Impact on Information Systems

  • Covers concepts in systems analysis and design

Objectives

  • Describe the organizational environment.

  • Discuss the nature of systems used in organizations.

  • Identify advantages of virtual organizations.

  • Describe uses of enterprise resources, including diagrams and their significance.

  • Understand levels of management and organizational culture.

Major Topics

  • Organizational environment

  • Nature of systems

  • Context-level data flow diagram

  • Entity-relationship diagram

  • Levels of management

  • Organizational culture

Organizations

  • Composed of interrelated and interdependent subsystems.

  • Boundaries and environments affect information system analysis and design.

Organizational Environment

  • Types of environments:

    • Community: geographical factors, demographics (education, income).

    • Economic: market factors and competition.

    • Political: influence of state and local government.

Open and Closed Systems

  • Open Systems:

    • Free-flowing information.

    • Output from one system serves as input to another.

  • Closed Systems:

    • Restricted access to information.

    • Information shared on a strictly need-to-know basis.

Virtual Organizations

  • Parts located in different physical locations.

  • Utilize computer networks and communication technology for collaboration.

Advantages of Virtual Organizations

  • Reduced costs of physical facilities.

  • Faster response to customer needs.

  • Flexibility for employees.

Enterprise Resource Planning (ERP)

  • Describes an integrated organizational information system.

  • Enhances information flow between organizational functional areas.

Context-Level Data Flow Diagram (DFD)

  • Tool for showing data used and information produced by a system.

  • Provides an overview of the system's environment, including entities supplying and receiving data.

Context-Level DFD Symbols

  • Entity: Represents a person, group, department, or system supplying/receiving information;

    • Labeled with a noun.

  • Process: Represents the entire system;

    • Labeled as number 0.

  • Data Flow: Represented by arrows showing information passage;

    • Labeled with nouns.

Entity-Relationship Diagrams (E-R Diagrams)

  • Help understand organizational system and data storage.

  • Symbols represent entities and relationships.

Types of Entities

  • Fundamental Entity:

    • Describes a person, place, or thing; symbol is a rectangle.

  • Associative Entity:

    • Links two entities; symbol is a diamond inside a rectangle.

  • Attributive Entity:

    • Describes attributes and repeating groups; symbol is an oval in a rectangle.

Relationships in E-R Diagrams

  • Show connections between entities with three types:

    • One-to-one

    • One-to-many

    • Many-to-many

  • Relationship lines are labeled; 'one' is indicated by a vertical line and 'many' by a crow's foot.

Creating Entity-Relationship Diagrams

  • Steps involve listing entities, identifying key entities, choosing primary entities, and confirming results with data gathering.

Managerial Control Levels

  • Three levels:

    • Operations Management:

      • Decisions with predictable outcomes; focuses on operating details.

    • Middle Management:

      • Short-term planning and control; operates between operational and strategic decisions.

    • Strategic Management:

      • Guiding future direction of the organization; operates in uncertain environments.

Organizational Culture

  • Culture consists of shared values, beliefs, and symbols.

  • Verbal Symbolism:

    • Language conveying myths, metaphors, visions.

  • Nonverbal Symbolism:

    • Artifacts like trophies, rites, rituals, clothing, and office decor.