Concepts of Information & Data Processing Lecture 6

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Information Concepts: Data, Information, and Knowledge

• Data: raw facts

–Alphanumeric, image, audio, and video

• Information: data organized in a form that human can interpret

–Value of Information is directly linked to how it helps decision makers achieve their organization’s goals and can be measured

• in time required to make a decision

• Increased profits to the company

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Figure 1.2: The Process of Transforming Data into Information

Data, Information, and Knowledge

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The Characteristics of Valuable Information

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Table 1.2: Characteristics of Valuable Information

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The Characteristics of Valuable Information (continued)

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Table 1.2: Characteristics of Valuable Information (continued)

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What Is an Information System?

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Figure 1.3: The Components of any Information System

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What Is an Information System?

An Information System (IS) is a collection of interrelated

components that collect, process, store, and provide as output

the information needed to complete a business task.

Example: A payroll system, for example, collects information

on employees and their work, processes and stores that

information, and than produces paychecks and payroll reports

for the organization. Then information is provided to

manufacturing so the department can schedule production.

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Computer-Based Information Systems • Computer-based information system (CBIS): single set of

hardware, software, databases, telecommunications, people, and procedures configured to collect, manipulate, store, and process data into information

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Computer-Based Information Systems • CBIS components

– Hardware: computer equipment used to perform input, processing, and output activities

– Software: computer programs that govern the operation of the computer

– Database: organized collection of facts and information

– Telecommunications: electronic transmission of signals for communications

– Networks: connect computers and equipment in a building, around the country, and around the world

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Types of Information System

• As far as organizations perform many different types of activity, they require several different types of information systems to support all of information needs.

• The information systems found in most businesses include • Transaction processing systems • Management information systems • Executive information systems • Decision support systems • Expert systems • Communication support systems • Office support systems

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Types of Information System (Cont..)

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Types of Information System (Cont..)

• Transaction processing systems (TPS)

• Capture and record information about the transactions that affect

the organization.

• A transaction occurs each time a sale is made, supplies are

ordered, an interest payment is made.

• Usually these transactions create credit or debit entries in

accounting ledgers.

• This kind of ISs were among the first to be automated by

computers.

• The modern TPS use state-of-the-art technology, for instance, in

the form of on-line TPS.

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Types of Information System (Cont..)

• Management information systems (MIS)

• systems that take information captured by TPS

• Produces reports that management needs for planning and controlling the business.

• MIS are possible because the information has been captured by the TPS and placed in organizational databases.

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Types of Information System (Cont..)

• Executive information systems (EIS)

• Provides information for executives to use in strategic planning.

• Some of the information comes from the organizational databases,

• but much of the information comes from external sources – news about competitors, stock market reports, economic forecasts, and so on.

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Types of Information System (Cont..)

• Decision support systems (DSS)

• allow a user to explore the impact of available options or decisions. Whereas

an MIS produce reports,

• DSS provide an interactive environment in which decision makers can quickly

manipulate data and models of business operations.

• A DSS has three parts. The first part is composed of a database (which may

be extracted from TPS or MIS).

• The second part consists of mathematical or graphical models of business

processes.

• The third part is made up of a user interface (or dialogue module) that

provides a way for the decision makers to communicate with the DSS.

• An EIS is a DSS that allows senior management to explore data starting at a

high level of aggregation and selectively drill down into specific areas where

more detailed information and analysis are required.

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Types of Information System (Cont..)

• Expert systems (ES)

• Replicate the decision-making process rather than manipulating

information.

• If-then-else rules or other knowledge representation forms

describe the way a real expert would approach situations in a

specific domain of problems.

• Typically, users communicate with an ES through an interactive

dialogue.

• The ES asks questions (which an expert would ask) and the end

user supplies the answers.

• Those answers are then used to determine which rules apply, and

the ES provides a recommendation based on the rules.

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Types of Information System (Cont..)

• Communication support systems (CSS) • allow employees to communicate with each

other and with customers and suppliers. • Communication support now includes e-mail,

fax, Internet access, and video conferencing. • Office support systems (OSS) • help employees create and share documents,

including reports, proposals, and memos. • OSS also help to maintain information about

work schedule and meetings.

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Additional Information Systems

• Knowledge Management Systems (KMS)

–create, store, share, and use the organization’s knowledge and experience

• Artificial intelligence (AI)

–field in which the computer system takes on the characteristics of human intelligence

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Data Processing

• Data processing:

• Any operation or set of operations performed upon data, whether or not by automatic means, such as collection, recording, organization, storage, adaptation or alteration to convert it into useful information.

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Data Processing Cycle

• Once data is collected, it is processed to convert it into useful information.

• The data is processed again and again until the accurate result is achieved. This is called data processing cycle.

• The data processing is very important activity and involves very careful planning.

• Usually, data processing activity involves three basic activities.

1. Input 2. Processing 3. Output

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Data Processing Cycle (Cont…)

1. Input

It is the process through which collected data is transformed into a form that computer can understand. It is very important step because correct output result totally depends on the input data. In input step, following activities can be performed.

i) Verification

The collected data is verified to determine whether it is correct as required. For example, the collected data of all B.Sc. students that appeared in final examination of the university is verified. If errors occur in collected data, data is corrected or it is collected again.

ii) Coding

The verified data is coded or converted into machine readable form so that it can be processed through computer.

iii) Storing

The data is stored on the secondary storage into a file. The stored data on the storage media will be given to the program as input for processing.

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Data Processing Cycle (Cont…)

2.Processing The term processing denotes the actual data manipulation techniques such as classifying, sorting, calculating, summarizing, comparing, etc. that convert data into information. i) Classification The data is classified into different groups and subgroups, so that each group or sub-group of data can be handled separately. ii) Storing The data is arranged into an order so that it can be accessed very quickly as and when required. iii) Calculations The arithmetic operations are performed on the numeric data to get the required results. For example, total marks of each student are calculated. iv) Summarizing The data is processed to represent it in a summarized form. this means that the summary of data is prepared for top management. For example, the summary of the data of student is prepared to show the percentage of pass and fail student examination etc.

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Data Processing Cycle (Cont…)

3. Output

After completing the processing step, output is generated. The main purpose of data processing is to get the required result. Mostly, the output is stored on the storage media for later user. In output step, following activities can be performed.

i) Retrieval

Output stored on the storage media can be retrieved at any time. For example, result of students is prepared and stored on the disk. This result can be retrieved when required for different purposes.

ii) Conversion

The generated output can be converted into different forms. For example, it can be represented into graphical form.

iii) Communication

The generated output is sent to different places. For example, weather forecast is prepared and. sent to different agencies and newspapers etc. where it is required.

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Types of Data Processing

• Manual Data Processing:

• This method of data processing involves human intervention.

• The manual process of data entry implies many opportunities for errors, such as delays in data capture, as every single data field has to be keyed in manually, a high amount of operator misprints or typos, high labor costs from the amount of manual labor required.

• Manual processing also implies higher labor expenses in regards to spending for equipment and supplies, rent, etc.

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Types of Data Processing

• EDP (electronic data processing): • an infrequently used term for what is today usually called "IS"

(information services or systems) or "MIS" (management information services or systems), is the processing of data by a computer and its programs in an environment involving electronic communication.

• EDP evolved from "DP" (data processing), a term that was created when most computing input was physically put into the computer in punched card form or in ATM cards form and output as punched cards or paper reports.

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Types of Data Processing

• Real time processing: • In a real time processing, there is a continual input, process and

output of data. Data has to be processed in a small stipulated time period (real time), otherwise it will create problems for the system.

• For example, when a bank customer withdraws a sum of money from his or her account it is vital that the transaction be processed and the account balance updated as soon as possible, allowing both the bank and customer to keep track of funds.

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Types of Data Processing

• Batch processing:

• In a batch processing group of transactions collected over a period of time is collected, entered, processed and then the batch results are produced.

• Batch processing requires separate programs for input, process and output.

• It is an efficient way of processing high volume of data.

• For example: Payroll system, Examination system and billing system.

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Computer Processing Operations

A computer can perform only the following four operations which enable computers to carry out the various data processing activities we have just discussed.

(a) Input/Output operations

A computer can accept data (input) from and supply processed data (output) to a wide range of input/output devices. These devices such as keyboards, display screens, and printers make human-machine communication possible.

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Computer Processing Operations

(b) Calculation and text manipulation Operations

Computer circuits perform calculations on numbers. They are also capable of manipulating numeric and other symbols used in text with equal efficiency.

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Computer Processing Operations

(c) Logic/Comparison Operations

A computer also possesses the ability to perform logical operations.

For example, if we compare two items represented by the symbols A and B, there are only three possible outcomes. A is less than B (A<B); A is equal to B (A=B): or A is greater than B (A>B).

A computer can perform such comparisons and the, depending on the result, follow a predetermined path to complete its work. This ability to compare is an important property of computers.

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Computer Processing Operations

(d) Storage and Retrieval Operations

Both data and program instructions are stored internally in a computer.

Once they are stored in the internal memory, they can be called up quickly or retrieved, for further use.

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Data Representation

• How do computers represent data?

• Most computers are digital

• Recognize only two discrete states: on or off

• Computers are electronic devices powered by electricity, which has only two states, on or off

off

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Data Representation What is the binary system?

Binary

Digit (bit)

Electronic

Charge

Electronic

State

• A number system that has just two unique digits, 0 and 1

• A single digit is called a bit (binary digit)

• A bit is the smallest unit of data the computer can represent

• By itself a bit is not very informative

• The two digits represent the two off and on states

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Data Representation

8-bit byte for the number 3

8-bit byte for the number 5

8-bit byte for the capital letter T

• What is a byte?

• Eight bits are grouped together to form a byte

• 0s and 1s in each byte are used to represent

individual characters such as letters of the alphabet,

numbers, and punctuation

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Data Representation

What are two popular coding systems to represent

data?

• American Standard Code

for Information Interchange

(ASCII)

• Extended Binary Coded

Decimal Interchange Code

(EBCDIC)

• Sufficient for English

and Western European

languages

• Unicode often used for

others

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Data Representation How is a character sent from the keyboard to the computer?

Step 1:

The user presses the letter T key

on the keyboard

Step 2:

An electronic signal for the letter

T is sent to the system unit

Step 3:

The signal for the letter T is

converted to its ASCII binary

code (01010100) and is stored in

memory for processing

Step 4:

After processing, the binary

code for the letter T is converted

to an image on the output device

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Number Bases

Number System Base Symbols

Binary 2 0, 1

Octal 8 0,1, 2, 3, 4, 5, 6, 7

Decimal 10 0,1, 2, 3, 4, 5, 6, 7, 8, 9

Hexadecimal 16 0,1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F

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Decimal Number System

• The number 4567 in base 10 means:

• 4567 = four thousand five hundred and sixty seven

= 4000 + 500 + 60 + 7

= (4 x 1000) + (5 x 100) + (6 x 10) + (7 x 1)

= (4 x 103) + (5 x 102) + (6 x 101) + (7 x 100)

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Decimal Number System (cont..)

• The number 512.49 in base 10 means:

512.49

= 500 + 10 + 2 + 0.40 + 0.09

= (5 x 100) + (1 x 10) + (2 x 1) + (4 x 0.1) + (9 x 0.01)

= (5 x 102) + (1 x 101) + (2 x 100) + (4 x 10-1) + (9 x 10-2)

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Binary number system

• Base of the binary number system is 2

• Symbols are 0 & 1

• The number 1101.11 in base 2 means:

1101.11

= (1 x 23) + (1 x 22) + (0 x 21) + (1 x 20) + (1 x 2-1) + (1 x 2-2)

= (1 x 8) + (1 x 4) + (0 x 2) + (1 x 1) + (1 x 0.5) + (1 x 0.25)

= 8 + 4 + 0 + 1 + 0.5 + 0.25

= 13.75 in decimal

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Octal number system

• Base of the octal number system is 8

• The symbols are 0, 1, 2, 3, 4, 5, 6 & 7

• The number 456.41 in base 8 means:

456.41

= (4 x 82) + (5 x 81) + (6 x 80) + (4 x 8-1) + (1 x 8-2)

= (4 x 64) + (5 x 8) + (6 x 1) + (4 x 0.125) + (1 x 0.15625)

= 256 + 40 + 6 + 0.5 + 0.15625

= 302.65625 in decimal

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Hexadecimal number system

• The base is 16

• The symbols are

• 0,1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F

• The number 1FA.4C in base 16 means:

1FA.4C

= (1 x 162) + (F x 161) + (A x 160) + (4 x 16-1) + (C x 16-2)

= (1 x 162) + (15 x 161) + (10 x 160) + (4 x 16-1) + (12 x 16-2)

= (1 x 162) + (15 x 161) + (10 x 160) + (4 x 16-1) + (12 x 16-2)

= 1x256 + 15 x 16 + 10 x 1 + 4 x0.0625 + 12 x 0.00390625

= 256 + 240 + 10 + 0.25 + 0.046875

= 506.296875 in decimal

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