Information Processing Content covered Data and information Information Qualities ...

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Information Processing

Content covered

Data and information Information Qualities Data/Information Processing

Commercial Information Processing Industrial Information Processing Scientific Data Processing

Information Retrieval and Management Sources of data Data Integrity

Verification Validation

Data and information

Data is the raw materials that is input into a computer system. It consists of characters, numbers and program code.

Information is data that has been processed by a computer system

Data and Information

How are data and information related?

Next

processing

data stored on diskStep 1. The member data, including a photograph, is entered and stored on the hard disk.

Step 2. The computer extracts the member data from disk.

Step 3. The receipt is created and printed.

Data is raw facts Information is data that is organized

and meaningful

receipt

Computers process data into information

UsefulUsefulAccessibleAccessible

OrganizedOrganized

Information Qualities

What are the qualities of valuable information?

p. 516 - 517 Next

TimelyTimely

VerifiableVerifiable

AccurateAccurate

Cost-effectiveCost-effective

Information Qualities

Accurate information is error free. Inaccurate

information can lead to incorrect decisions.

Verifiable information can be proven as correct or

incorrect.

Timely information has an age suited to its use. Most

information loses value with time.

Information Qualities

Organized information is arranged to suit the needs

and requirements of the decision maker.

Accessible information is available when the decision

maker needs it. Having to wait on information may

delay important decision.

Useful information has meaning to the person who

receives it.

Information Qualities

Cost-effective information should give more value

than it costs to produce.

Data/Information Processing

Information (or data) processing refers to computer-based systems that take in data and generate information

Information Processing

There are many ways in which data can be processed to become information. Here are some of them:

Carrying out calculations in a spreadsheet

Printing a document or image

Displaying an image on the screen

Updating data in a file.

Sorting data into alphabetical order.

Commercial data processing

Computer systems are used in many businesses to carry out some time-consuming administrative tasks. Examples:- Payroll – calculating employees pay Orders – recording orders placed by customers Sales – in a shop, dealing with purchases at the till Invoices – sending request for payment to customers Accounts – keeping track of receipts and payments Marketing – designing packaging and advertising Correspondence – sending letters and emails

Industrial data processing

Industrial and manufacturing businesses need to carry out all the business task. In addition, they have further use for data processing such as:

Control systems – controlling the processes used when manufacturing products

Computer Aided Design – designing products Computer Aided Engineering – using special software Computer Aided Manufacture – using special software

to develop and test products

Control systems

We can use information processing systems to control machines automatically. Here are some examples:-

Factories are often largely automated, e.g. manufacturing chemicals, packaging goods.

The signalling systems on many railways across the world are controlled by computers, to ensure that the trains pass safely

Control systems

Some factories use robots to manufacture goods, such as automobiles.

Most electronic equipment in the home has some element of computer control, e.g. VCR’s, digital televisions, digital cameras, microwave oven, washing machines, cell phones

Control systems

They are two main types of control system:

Automation systems – these are straightforward type of control system in which tasks are carried out automatically. For e.g. running a washing machine.

Process control systems – these are a type of control system used in manufacturing in which actions are changed depending on feedback from sensors. A sensor can measure things like temperature, humidity, light, sound, movement and pressure.

Scientific data processing

Scientist can gather a lot of data during

an experiment. Sometimes they will use

sensors to capture data over a period of

time. In other experiments the scientist

themselves may be recording readings

on a source document.

Information Retrieval

When data stored on a computer

system is searched and the relevant

information is found, this is known

as information retrieval.

Information management

Information management ensures

that all data is input accurately,

stored correctly, retrieved easily

and output in a way that provides

useful information.

SOURCES OF DATA

Source Document Human Readable Machine Readable Turnaround Document

Source Documents

A source document is the original form or paper

from which data was taken. Examples of source

documents time cards, order forms, invoices, pay

cheques, brochures, photographs, inventory tags

etc.

Human Readable

Human readable language

refers to a language that a

human can fully read and

understands. For example the

language of origin (whether

English, Spanish or French) of

an individual or a language

learnt along the path of life.

Machine Readable

Machine readable language

is the language that the

computer understands. For

example information read

from a storage device.

Turnaround Documents

A turnaround document is a

document that you return to the

company that creates and sends

it. For example electricity bills,

water bills, telephone bills etc.

The customers normally tear off

a portion of the bill and send it

back with the payment.

Data Integrity

What is data integrity?

p. 516 Next

Degree to which data is correct Garbage in, garbage

out (GIGO)—computer phrase that means you cannot create correct information from incorrect data

Garbage out

Garbage in

Data integrity is lost

Data Verification

Data verification is the process by which an individual

checks to ensure that the information keyed in by

another person is correctly entered into a computer

system. Data verification is a process carried out by

humans.

Data Verification errors

Two common errors:-

Typographical errors

Transpositional errors

Data Verification methods

Proofreading – checks the data entered against the

data on the original source document. The person

entering the data reads the source document and

checks that it matches what he or she entered into

the computer.

Data Verification methods (cont’d)

Double-entry – is where the same data is entered

twice, sometimes by different people. If the data

differs between the two entries, it does not get

processed. It can be expensive and time-consuming

to use this method, but it does ensure very accurate

data capture.

Validation

What is validation?

Next

Process of comparing data with a set of rules

to find out if data is correct.

Data validation is an automatic process

carried out by software.

Reduce data entry errors and enhance data

integrity before program writes data on disk.

Types of Data Validation

Range checks – ensures that numbers entered fall

within a specific range. If someone enters 25 hours

in a day that will not be calculated.

Data type checks – ensures that the right type of

data has been entered. You do not type letters in a

telephone numbers.

Types of Data Validation (cont’d)

Consistency checks – compares data you have

entered against other data you have entered. If you

enter a person’s year of birth and their age in

separate fields, a consistency check will ensure that

the two fields correspond with each other.

Types of Data Validation (cont’d)

Reasonableness checks - ensures that the data is

reasonable – not completely unrealistic. If you are

entering salary information into a payroll system, a

reasonableness check will ensure that you do not

enter extra zeros (0’s) by mistake.

Verification Vs. Validation

Verification is the process of determining the correctness of

the data. (e.g. Was this done right or not?) { Verification is a

Preventive process/actions, which makes it a QA process }

Testing against specifications.

Validation is the process of determining if the data is

correct. (e.g. Was this the right thing to do or not?)

{ Validation is a Corrective process/actions , which makes

QC process} Testing against requirements

Verification Vs. Validation

Validation is the checking of data before processing to ensure

that it is acceptable for it or not. E.g. When entering a date, the

validation for month is 1-12, you cannot enter 13, its out of

range. Similarly a telephone number cannot contain letters.

Whereas Verification is the checking of data that has been

copied from one place to another to ensure that is replaces the

original one. E.g. PASSWORD. When you sign up in a site, just

like WIKIANSWERS, you have to enter your password twice,

the second entry being compared with the first.

End of presentation

Thank you for your undivided attention