Chapter 1 Introduction to Information Systems. Information Concepts (1) Data vs. Information Data...

Chapter 1

Introduction toInformation Systems

Information Concepts (1)

Data vs. Information Data

• Raw facts

• Distinct pieces of information, usually formatted in a special way

Information• A collection of facts organized in such a way that

they have additional value beyond the value of the facts themselves

Data ‘Discussion’ (1)

(1) Distinct pieces of information, usually formatted in a special way. All software is divided into two general categories: data and programs. Programs are collections of instructions for manipulating data.

Data can exist in a variety of forms -- as numbers or text on pieces of paper, as bits and bytes stored in electronic memory, or as facts stored in a person's mind.

Strictly speaking, data is the plural of datum, a single piece of

information. In practice, however, people use data as both the singular and plural form of the word.

(2) The term data is often used to distinguish binary machine-readable information from textual human-readable information. For example, some applications make a distinction between data files (files that contain binary data) and text files (files that contain ASCII data).

(3) In database management systems, data files are the files that store the database information, whereas other files, such as index files and data dictionaries, store administrative information, known as metadata.

Terminology

Process• A set of logically related tasks performed to achieve

a defined outcome

Process• (n) An executing program. The term is used loosely

as a synonym of task.

• (v) To perform some useful operations on data.

Terminology

Knowledge• An awareness and understanding of a set of

information and how that information can be made useful to support a specific task

Knowledge base• The collection of data, rules, procedures, and

relationships that must be followed to achieve value or the proper outcome

Types of Data

Data Represented by

Alphanumeric data Numbers, letters, and other characters

Image data Graphic images or pictures

Audio data Sound, noise, tones

Video data Moving images or pictures

Data Information

Data InformationTransformation

Characteristics of Valuable Information

Characteristics Accurate, complete, economical, flexible,

reliable, relevant, simple, timely, verifiable, accessible, secure

Accessible: Information should be simple, not overly complex. Sophisticated and detailed information might not be needed. In fact, too much information can cause information overload, whereby a decision maker has too much information and is unable to determine what is really important.Information should be easily accessible by authorized users so they can obtain it in the right format and at the right time to meet their needs.

Accurate: Accurate information is error free. In some cases, inaccurate information is generated because inaccurate data is fed into the transformation process. (This is commonly called garbage in, garbage out [GIGO].)

Complete: Complete information contains all the important facts. For example, an investment report that does not include all important costs is not complete.

Economical: Information should also be relatively economical to produce. Decision makers must always balance the value of information with the cost of producing it.

Flexible information can be used for a variety of purposes. For example, information on how much inventory is on hand for a particular part can be used by a sales representative in closing a sale,by a production manager to determine whether more inventory is needed, and by a financial executive to determine the total value the company has invested in inventory.

Relevant Relevant information is important to the decision maker. Information showing that lumber prices might drop might not be relevant to a computer chip manufacturer.

Reliable Reliable information can be trusted by users. In many cases, the reliability of the information depends on the reliability of the data-collection method. In other instances, reliability depends on the source of the information. A rumor from an unknown source that oil prices might go up might not be reliable

Secure: Information should be secure from access by unauthorized usersSimple : Accessible Information should be simple, not overly complex. Sophisticated and detailed information might not be needed. In fact, too much information can cause information overload, whereby a decision maker has too much information and is unable to determine what is really important.

Verifiable: Information should be verifiable. This means that you can check it to make sure it is correct, perhaps by checking many sources for the same information.

Timely: Timely information is delivered when it is needed. Knowing last week’s weather conditions will nothelp when trying to decide what coat to wear today.

System

System A set of elements or components that interact

to accomplish goals A combination of components working

together

System ‘Discussion’

(1) Refers to a combination of components working together. For

example, a computer system includes both hardware and software.

A Windows system is a personal computer running the Windows

operating system. A desktop publishing system is a computer

running desktop publishing software.

(2) Short for computer system.

(3) Short for operating system.

(4) An organization or methodology. The binary numbering system,

for instance, is a way to count using only two digits.

System Elements

Inputs Processing mechanisms Outputs

System Example

System

Elements

GoalInputs

Processingelements

Outputs

Movie

Actors, director, staff, sets, equipment

Filming, editing, special effects, distribution

Finished film delivered to movie studio

Entertaining movie, film awards, profits

System Performance and Standards

Efficiency A measure of what is produced divided by what is

consumed

Effectiveness A measure of the extent to which a system achieves its

goals

System performance standard A specific objective of the system (next 2 slides)

Figure 1.5a

Figure 1.5b

System Variables and Parameters

System variable A quantity or item that can be controlled by the

decision maker E.g. the price a company charges for a product

System parameter A value or quantity that cannot be controlled

by the decision maker E.g., cost of a raw material

Information System (IS)

Definition A set of interrelated elements or components that

collect (input), manipulate (process), and disseminate (output) data and information and provide a feedback mechanism to meet an objective

(IS) Pronounced as separate letters, and short for Information Systems or Information Services. For many companies, IS is the name of the department responsible for computers, networking and data management. Other companies refer to the department as IT (Information Technology) and MIS (Management Information Services).

What is an Information System?

Schematic model of an information system

Input Processing Output

Feedback

Input, Processing, Output,

Input The activity of gathering and capturing data Whatever goes into the computer

Processing Converting or transforming data into useful outputs

Output Useful information, usually in the form of documents

and/or reports Anything that comes out of a computer

Input ‘Discussion’

(n) Whatever goes into the computer. Input can take a variety of forms, from commands you enter on a keyboard to data from another computer or device. A device that feeds data into a computer, such as a keyboard or mouse, is called an input device.

(v) The act of entering data into a computer

Output ‘Discussion’

(n) Anything that comes out of a computer. Output can be meaningful information or gibberish, and it can appear in a variety of forms -- as binary numbers, as characters, as pictures, and as printed pages. Output devices include display screens, loudspeakers, and printers.

(v) To give out. For example, display screens output images, printers output print, and loudspeakers output sounds.

Feedback

Feedback Output that is used to make changes to input or

processing activities

Forecasting A proactive approach to feedback Use for estimating future sales or inventory

needs

Manual vs. Computerized Systems

Manual systems still widely used E.g., some investment analysts manual draw charts

and trend lines to assist them in making investment decisions

Computerized systems E.g., the above trends lines can be drawn by computer

Evolution Many computerized system began as manual systems E.g., directory assistance (“411”)

Computer-based Information Systems

A CBIS is composed of… Hardware Software Databases Telecommunications People Procedures

Together they are… Configured to collect, manipulate, store, and process

data into information

Technology Infrastructure

Another term for CBIS Consists of the shared information system

(IS) resources that form the foundation of the information system

Parts of a CBIS

Five parts Hardware Software Database Telecommunications Networks

Hardware

Hardware Computer equipment used to perform input,

processing, and output activities The objects that you can actually touch, like

disks, disk drives, display screens, keyboards, printers, boards, and chips.

Hardware ‘Discussion’

Hardware refers to objects that you can actually touch, like disks, disk drives, display screens, keyboards, printers, boards, and chips. In contrast, software is untouchable. Software exists as ideas, concepts, and symbols, but it has no substance.

Books provide a useful analogy. The pages and the ink are the hardware, while the words, sentences, paragraphs, and the overall meaning are the software. A computer without software is like a book full of blank pages -- you need software to make the computer useful just as you need words to make a book meaningful.

Parts of a CBIS


Software

Software Computer programs that

govern/determine/control the operation of the computer

Computer instructions or data

Software ‘Discussion’ (1)

Software is computer instructions or data. Anything that can be stored electronically is software. The storage devices and display devices are hardware.

The terms software and hardware are used as both nouns and adjectives. For example, you can say: "The problem lies in the software," meaning that there is a problem with the program or data, not with the computer itself. You can also say: "It's a software problem.“

Software ‘Discussion’ (2)

The distinction between software and hardware is sometimes confusing because they are so integrally linked. Clearly, when you purchase a program, you are buying software. But to buy the software, you need to buy the disk (hardware) on which the software is recorded.

Software is often divided into two categories. Systems software includes the operating system and all the utilities that enable the computer to function. Applications software includes programs that do real work for users. For example, word processors, spreadsheets, and database management systems fall under the category of applications software.

Parts of a CBIS


Database

Database An organized collection of facts and

information A collection of information organized in such a

way that a computer program can quickly select desired pieces of data

Database ‘Discussion’ (1)

A database is a collection of information organized in such a way that a computer program can quickly select desired pieces of data.

You can think of a database as an electronic filing system. Traditional databases are organized by fields, records, and files. A field is a single piece of information; a record is one complete set of fields; and a file is a collection of records. For example, a telephone book is analogous to a file. It contains a list of records, each of which consists of three fields: name, address, and telephone number.


An alternative concept in database design is known as Hypertext. In a Hypertext database, any object, whether it be a piece of text, a picture, or a film, can be linked to any other object. Hypertext databases are particularly useful for organizing large amounts of disparate information, but they are not designed for numerical analysis.

To access information from a database, you need a database management system (DBMS). This is a collection of programs that enables you to enter, organize, and select data in a database.

Parts of a CBIS


Telecommunications

Telecommunications The electronic transmission of signals for

communications; enables organizations to link computer systems into effective networks

Refers to all types of data transmission, from voice to video

Parts of a CBIS


Networks

Network Used to connect computers and computer

equipment in a building, around the country, across the world, to enable electronic communications

A group of two or more computer systems linked together

Network ‘Discussion’ (1)

There are many types of computer networks, including:

local-area networks (LANs) : The computers are

geographically close together (that is, in the same building).

wide-area networks (WANs) : The computers are farther apart and are connected by telephone lines or radio waves.


In addition to these types, the following characteristics are also used to categorize different types of networks:

topology : The geometric arrangement of a computer system. Common topologies include a bus, star, and ring.

protocol : The protocol defines a common set of rules and signals that computers on the network use to communicate. One of the most popular protocols for LANs is called Ethernet. Another popular LAN protocol for PCs is the IBM token-ring network .

architecture : Networks can be broadly classified as using either a peer-to-peer or client/server architecture.


Computers on a network are sometimes called nodes.

Computers and devices that allocate resources for a network are called servers.

Internet and Intranet

Internet The world’s largest telecommunications network A network of networks Free exchange of information A global network connecting millions of computers

Intranet A network that uses Internet technology within an

organization A network belonging to an organization

People and Procedures

People The most important element in most computer-

based information systems Includes people who manage, run, program,

and maintain the system E.g., IT professionals (you!)

Procedures Includes the strategies, policies, methods, and

rules for using the CBIS

Business Information Systems

Types Transaction processing systems E-commerce systems Management information systems Decision support systems Expert systems

Transactions Processing Systems

Transaction Any business-related exchange E.g., generating a weekly payroll

Transaction processing system (TPS) An organized collection of people, procedures,

software, databases, and devices used to record completed for for business related exchanges

Payroll Example

Hoursworked

Hoursworked

Payrate

Payrate

Payrolltransactionprocessing

Payrolltransactionprocessing

Payrollchecks

Payrollchecks

E-Commerce System

E-commerce Involves any business transaction executed

electronically Conducting business on-line For example, between…

• Companies

• Companies and consumers

• Business and the public sector

• Consumers and the public sector

Example for placing a purchase order

Purchase Order - Traditional

Purchase Order – E-commerce

Management Information Systems

An MIS is… An organized collection of people, procedures,

software, databases, and devices used to provide routine information to managers and decision makers

Schematic of MIS

Commondatabases

Marketingmanagementinformation

system

Marketingmanagementinformation

system

FinancialmanagementInformation

system

FinancialmanagementInformation

system

ManufacturingmanagementInformation

system

ManufacturingmanagementInformation

system

Ordermanagementinformation

system

Ordermanagementinformation

system

TPSTPS

MIS ‘Discussion’

Short for management information system or management information services, and pronounced as separate letters, MIS refers to a class of software that provides managers with tools for organizing and evaluating their department. Typically, MIS systems are written in COBOL and run on mainframes or minicomputers.

Within companies and large organizations, the department responsible for computer systems is sometimes called the MIS department. Other names for MIS include IS (Information Services) and IT (Information Technology).

Decision Support Systems

A DSS is… An organized collection of people, procedures,

software, databases, and devices used to support problem-specific decision making

A DSS helps a manger “do the right thing”

Expert Systems

An expert system is… A computer application that performs a task that would

otherwise be performed by a human expert gives the computer the ability to make suggestions and

to act like an expert in a particular field Examples: diagnose human illnesses, make financial

forecasts, schedule routes for delivery vehicles

Expert systems typically include “artificial intelligence” (next slide)

Artificial Intelligence (1)

The branch of computer science concerned with making computers

behave like humans. The term was coined in 1956 by John McCarthy

at the Massachusetts Institute of Technology. Artificial intelligence

includes games playing: programming computers to play games such as

chess and checkers expert systems : programming computers to make decisions in real-life

situations (for example, some expert systems help doctors diagnose diseases based on symptoms)

natural language : programming computers to understand natural human languages


neural networks : Systems that simulate intelligence by attempting to reproduce the types of physical connections that occur in animal brains

robotics : programming computers to see and hear and react to other sensory stimuli

Currently, no computers exhibit full artificial intelligence (that is, are able to simulate human behavior). The greatest advances have occurred in the field of games playing. The best computer chess programs are now capable of beating humans. In May, 1997, an IBM super-computer called Deep Blue defeated world chess champion


Gary Kasparov in a chess match.

In the area of robotics, computers are now widely used in assembly plants, but they are capable only of very limited tasks. Robots have great difficulty identifying objects based on appearance or feel, and they still move and handle objects clumsily.

Natural-language processing offers the greatest potential rewards because it would allow people to interact with computers without needing any specialized knowledge. You could simply walk up to a


computer and talk to it. Unfortunately, programming computers to

understand natural languages has proved to be more difficult than

originally thought. Some rudimentary translation systems that

translate from one human language to another are in existence, but

they are not nearly as good as human translators. There are also

voice recognition systems that can convert spoken sounds into

written words, but they do not understand what they are writing;

they simply take dictation. Even these systems are quite limited --

you must speak slowly and distinctly.


In the early 1980s, expert systems were believed to represent the future of artificial intelligence and of computers in general. To date, however, they have not lived up to expectations. Many expert systems help human experts in such fields as medicine and engineering, but they are very expensive to produce and are helpful only in special situations.

Today, the hottest area of artificial intelligence is neural networks, which are proving successful in a number of disciplines such as voice recognition and natural-language processing.


There are several programming languages that are known as AI

languages because they are used almost exclusively for AI

applications. The two most common are LISP and Prolog.

Working with Systems (1)

Systems development The activity of creating or modifying an existing

business system

Systems investigation and analysis Defines the problems and opportunities of an existing

system

Systems design Determine how a new system will work to meet

business needs

Working with Systems (2)

Systems implementation Creating and acquiring system components

defined in the design

Systems maintenance and review Checks and modifies the system so that it

continues to meet changing business needs

End of Chapter 1

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