Data and Information Starter Mr Tettenborn

What are these They make this 34.5 what will this be then?

Answers 12,17,38 and 71 are examples of data 34.5 is the average and therefore information

Data, Information

Definitions Data:Raw Facts and figures or a set of values, measurements Process: Any operation that transfers data into information Information: Output from an ICT system or data that has been processed and gives us Knowledge Knowledge (Definition not required for examination): Knowing how to use the information created by an information sysem correctly

Which is the odd one out

Examination Grades C E A U Which is the odd one out

Introduction In this presentation we cover where data comes from and factors we need to take into account when gathering data for processing

Homework Complete the GIGO and definitions worksheet S:\Student Area\Subjects\ICT\Year 12\AS ICT\INFO2 Living in the digital world\INFO 2.2 Data and Information This will be printed out before next lesson and peer assessed.

Data Sources Data can be collected either: DIRECTLY – Gathered from an original source or INDIRECTLY – Gathered from an another source or as a by-product of another operation In the world of business these would be described as primary and secondary sources of data

Direct (Original) Data Sources Sale of an item in a supermarket recorded at EFTPOS terminal Data from sensors e.g. a weather station Data collected in a survey e.g. a questionnaire or an interview

Indirect Data Sources 1 Data collected for one purpose and used for another – A credit card company collects data about your spending in order to bill you each month. However, a secondary use of this data is to build up a “profile” of your spending habits. This data can then be used to send you direct marketing about goods and services that may appeal to you. Credit Card Transaction Indirect Use of Data Direct Use of Data Customer Billing Direct Marketing

Indirect Data Sources 2 Purchased data/data passed on – There are a number of ways data can be acquired from 3 rd parties and then used for a different purpose – A good example is the electoral roll. Its main use is to gather data about who is eligible to vote. However, marketing companies make extensive use of the roll to target customers.

Task Go to : S:\Student Area\Subjects\ICT\Presentations\Unit 1 Hardware\ Input Devices. Read through presentation and make notes Create a spider diagram showing how Data Can arise (see p130)

Encoding Task: What formats are the following examples of.txt.csv.jpg.mpg.bmp.wav.midi

Coding Data Before being stored in a computer information can be coded as data e.g. – M or F – Mo, Tu, We, Th, Fr, Sa, Su – I, II, IIIM, IIIN, IV, V – S, M, L, XL, XXL In the picture shown we can see the date code for the tyre This represents the eighth week of 2006

Benefits of Coding Less storage space is required – M and F require less storage space than male and female Faster data input – See above Validation is easier – With a limited number of codes it is easier to match them against rules to check they are entered correctly

Drawbacks of Coding Precision of data can be lost (coarsened) – In the example all shades of blue are coded as “blue” The user needs to know the codes used – How many of these top level domains do you know? – au, ch, de, ie, pk, fr, il, lk, es Data in Stored data PinkBlueBlackBlue

Coding Value Judgements Coding value judgements can be a particular problem as they are subject to personal opinion What do you think of this presentation? – Good? Average? Poor? – One person’s good may be another person’s poor!!! Value judgements are very difficult to encode without some coarsening (loss of detail) How would you improve the analysis? What are the time/cost implications?

Task Create a data entry form for evaluating how successful students feel their Year 12 Examinations were.

Quality of the Data Source 1 GIGO (Garbage In Garbage Out) If data input is poor the resulting information output will be poor i.e. corrupt, inaccurate etc. Can you think of any “real life” examples? Garbage In Garbage Out

Quality of the Data Source 2 Examples of GIGO can include: Unreliable questionnaires/surveys – e.g. inappropriate samples, badly worded questions etc. Incorrectly calibrated instruments – e.g. an incorrectly calibrated balance will give incorrect measures of mass Human error – e.g. transcription errors when entering data Incomplete data sets – e.g. failing to account for “shrinkage” when measuring supermarket stock

Types of Data Numbers Text Sound MIDI (Musical Instrument Digital Interface) Bit-mapped graphics Vector graphics

Internal Data Storage Computers use a number system called binary. It uses two digits (0 and 1) Known as BIT (BInary digiT) Bits are generally grouped together as 8 bits (called a byte)

Decimal Numbers (Base 10) Remember your earliest sums in primary school ‘Hundreds, Tens & Units’ H T U (100 x 6) = 600 (10 x 5) = 50 (1 x 3) = 3 Total= Notice how the numbers (place values) multiply by 10 as we move from right to left which becomes:- Let’s look at:-

Binary Numbers (Base 2) Instead of : ‘Hundreds, Tens & Units’ we have: ‘Eights, Fours, Twos and Units’ (8 x 1) = 8 (4 x 1) = 4 (2 x 0) = 0 (1 x 1)= 1 Total= Notice how the numbers (place values) multiply by 2 as we move from right to left Let’s look at: which becomes:-

The pattern of 0’s and 1’s may be:- A number  the number ‘24’ A character  the letter ‘A’ A program instruction  the instruction ‘Add’ A sound  MP3 file Image(s)  Jpg, Bmp. Video.

ASCII Code American Standard Code for Information Interchange Character ASCII Char ASCII Char ASCII Char ASCII space P h ! Q i " : R j £ ; S k $ < T l % = U m & > V n ' ? W o ) A Y q * B Z r C [ s , D \ t E ] u F ^ v / G _ w

Digitised sound Input via a microphone - converted from analogue to digital by taking samples Higher sampling rate = Better sound quality

MIDI (Musical Instrument Digital Interface) Allows the computer to communicate with musical instruments Records information about each note Very compact format - takes around 1/20th of disk space than “recorded” sound

Bit-mapped graphics Data about each pixel (picture element) is stored – even if the element contains just white space Bigger the picture, the more pixels are stored thus larger file size Do not scale well - gives jagged edges

Vector Graphics Graphics represented by recording geometric data – A line is defined by End-points colour width Can be re-sized without distortion Creates smaller files

Encoding Task: What formats are the following examples of.txt.csv.jpg.mpg.bmp.wav.midi

Value and importance of information

Objectives: Understand that information is a commodity and as such can have a monetary value, the level of which depends on – its accuracy, – its potential use and – its particular intended use. Describe the overheads involved in ensuring that information is up-to-date.

Objectives: Understand that information is a commodity and as such can have a monetary value, the level of which depends on – its accuracy, – its potential use and – its particular intended use. Describe the overheads involved in ensuring that information is up-to-date.

VALUE OF INFORMATION Information has a value – Often when a company goes bankrupt the value of the database is more than of the company! However, for information to be valuable it must be… – Accurate – Up to date – Relevant

Accurate Valuable information is accurate: – It has been collected carefully – It has been checked for errors – It is updated regularly

Up to Date Valuable information is up to date: – Some data has relevance over a long period of time eg. Geological data, historical data etc – Other data ages very quickly eg. stock and share prices, weather data etc – Date stamping helps to prevent management decisions being based on very out-of-date information.

Relevant Valuable information must be relevant for a particular use – Eg. information intended for a branch manager of a supermarket showing till usage to allow them to allocate staff over a weekly period would not be of use to the Regional manager wanting a view of the efficiency of all branches

Also …..complete Valuable information contains all relevant data. Eg. Information on car ownership has much more value if it includes: – When the car was bought – Where it was bought – Amount of money spent

… from a reliable source The Internet has shown the value of reliable sources Firms like Reuters ( have a good reputation – so charge more for information. Stocks and Share info – price predictions etc. particularly vulnerable to poor info.

WHY IS INFORMATION VALUABLE? For Marketing… – Who are the important customers? – What characteristics do the customers have? – Who could be potential customers? – Can we target new products to specific customers? Aid efficiency… – Stock tracking – Just In Time ordering

WHY IS INFORMATION VALUABLE? The information provided by a system could do some of the following: – Reduce costs – Eliminate loses – Reduce wastage – Use resources more effectively – Provide better management information to aid more accurate decision making.

COSTS OF INFORMATION Collecting the data Forms have to be printed and staff have to collect this information Data conversion for direct input Involves converting the data into a computer readable form. If special forms are used that contain data capable of being read directly by the computer, then these costs can be reduced.

COSTS OF INFORMATION Frequency of Collecting The more often data is collected, the more likely it is to be up to date, but… Collecting data too frequently would be expensive, so a compromise needs to be reached. Control Mechanisms Control mechanisms prevent the information from being seen by anyone who shouldn’t see it. Information is a marketable commodity and its protection costs money.

COSTS OF INFORMATION Validation Data being entered into a system is subjected to validation checks. Some of the data will be rejected. In some systems, data which fails the validation checks will need to be investigated manually. This involves further costs.

COSTS OF INFORMATION Frequency of the processing cycle To keep information up to date it is necessary to perform some processing This ties up computing time and other resources. It is therefore necessary to restrict the frequency of the processing. Need to strike a balance

COSTS OF INFORMATION Output Printing out of stock lists prevents the printers from being used for other purposes. The large volumes of paper used costs money… There are also the cost of electricity, and toner or ink jet cartridges. The costs of all these may restrict the style or format of the output and its frequency.

Task: Draw Out the Processing Diagram on page 132 giving examples of where each way is used. Answer the questions on page 134 Draw a spider diagram on how data can arise Design a poster for quality of information. Complete Data Worksheet in sahred area: (S:\Student Area\Subjects\ICT\Year 12\AS ICT\INFO2 Living in the digital world\INFO 2.2 Data and Information)

Summary/Revision Topics Data can arise from direct and indirect sources Information can be coded as data This has a number of benefits but can lead to coarsening The source/accuracy of data has a major impact on the quality of information produced i.e. GIGO

Revision Tasks Use your textbook/Internet sources to make your own notes on: – Sources of Data – Encoding Data – Quality of Data Sources Try questions on this worksheet Diagram/example on slide 9 courtesy of teach-ict.com. See the original here.teach-ict.comhere