Management Information Systems

1. Charles Parker 2nd Edition Management Information Systems Chapter 3:System & Models Prepared By: HamadRaza (Lecturer GCUF)

2. Systems • A system is made up of a number of parts combined in a particular way to do something useful. We think of the combined parts as a single thing and we give it a name. • Wheels, axles, pedals, gears, chain, seat and handlebars are combined to form a single whole we call a bicycle. A bike is a system when all the parts are connected correctly because it allows the rider to move from one place to another more easily.

3. Systems • A system is a set of integrated elements that collectively work together to achieve some common purpose or goal. • For Example: A football games is played according to the system that is composed of such elements as teams, stadiums, equipment, referees and rules. • A CBIS is a collection of people, hardware, software, data & procedures that interact to provide timely data and information, both internally and externally to authorized people who need it.

4. Components of a System • A system component / element can be tangible object such as a car or a person, an abstract concept such as data or information, or an event such as March 23 or “groundbreaking ceremony”. • Tangible objects of course are those objects that we can touch or measure. • Abstract concepts & events are intangible.

5. Components of a System • When classifying systems, we frequently differentiate between a system’s logical description & physical description. • Logical description of a system is a representation that specifies essential system elements in broad, often abstract terms. • A physical description of the same system would be much more precise about how it is actually implemented.

6. System Environment • All systems function within some sort of environment. • The environment, like the system, is a collection of elements. • These elements surround the system and often interact with it. • Systems are normally delimited by a boundary, which separates them from their environment. • Anything within the boundary is part of the system; • Anything outside is a part of the environment.

7. Open Versus Closed Systems • Systems are often classified as open or closed. • A closed system is self-contained and does not interact or make exchanges across its boundaries with its environment. • In other words, a closed system is one that has no interaction with any element not contained in it. • An open system is one that interacts and makes exchanges with its environment. • Most of the systems that occur naturally in business are open systems, and they interact with such environmental elements as consumers, suppliers, competitors, government and foreign countries.

8. Systems Models • When studying system, it is often convenient to represent them in the form of a model. • What is a Model? • A Presentation of a real world elements and the relationship among them. • For Example: 777 is a physical model of plane. • The equation “Area = Length * Width” is a math model for calculating the internal area of rectangle. • Porter’s five forces Model, Management level’s Model etc. • Why we need Models • The field of MIS uses many Models. Because management information system are often complex, it help to have a few models that simplify and clarify them.

9. General Versus Specific Models • Models can be classified in many ways. One way concerns how general or specific the models are: • General models are models that can be applied to wide variety of settings. • Specific models are those that apply to a specific situation. • For Example: Many of the graphical models Like Management Hierarchy Chart is a general model that can represent virtually any type of organization.

10. Types of Models • Models can be classified in several other ways. These are: • Graphical Models are models generally use such symbols as icons, boxes and lines to represent real-world elements and the relationships among them.

11. Types of Models • Graphical Models (Cont.) • Data flow diagrams (DFD) are widely used by systems analysts to graphically illustrate information systems. • These graphical models show how data or information move from one process to another in an organizational system. • These are useful for showing how systems work and are often used by systems analysts both to design systems & to clarify to users, programmers and other system analysts how components of a system fit together.

12. Types of Models • Graphical Models (Cont.) • Data flow diagrams (DFD)

13. Types of Models • Mathematical Models • A mathematical model is used to express quantifiable phenomena in mathematical terms. • Q = economic order quantity of specific product • D = annual usage of the product • S = the cost of placing an individual order • P = Price for the product • H = Unit cost of carrying items in inventory

14. Types of Models • Narrative Models • A Narrative models describes system without trying to illustrate it in a formula or graph. • For Example: A written description of a worker’s job duties. • Physical Models • A physical model is usually a three-dimensional representation that can be held or touched. • For Example: System prototype is a physical model. A prototype is a small “pilot” model of a hardware or software system that is used to guide the systems analyst in building a larger system.

15. Who is responsible for Developing Models? • Graphical & Narrative models of CBIS are usually constructed by system analysts. • Whereas Mathematical models are commonly created by the operations research or management science staff, who are specially trained in building mathematical models.