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Data Raw facts and figures – on their own they have no meaning e.g. readings from sensors, survey facts Information Data which has been processed by the computer. It has a context which makes it meaningful Knowledge Is derived from information by applying rules to it. Using information to make decisions Data: 1,12, 1.4,2, 12, 1.2, 3,16, 1.1 Information: Swim times for 100m Swimmer No Age group Times (mins) 1 12 1.4 2 12 1.2 3 16 1.1 Knowledge: Swimmer No 2 is the fastest in the age group. Data types • Boolean – Can hold one of two values – true/false, YES/NO 1/0 e.g are you disabled? • Integer – Holds whole numbers only e.g. school years 7 8 9 10 • Real – Holds decimal numbers e.g. for storing currency • Text/String – Holds any alphanumeric character, can include numbers and symbols e.g name address postcode tel no Coded Data Advantages • Save memory • Faster to type in • Less likely to have transcription errors • Greater consistency of data Disadvantages • Value judgments fitting into a certain category or group • Coarsen data by fitting itHow into groups clever am I ? •Thick •Average •Very •Genius Good quality information is up-to-date, accurate, and complete, relevant and correctly targeted •Add value by aiding decision making Decision-making is based on information that is available at the time and if this is either out-of-date or incomplete then this can have a bad effect on the organisation or company. •Monitor progress. Information obtained by market research (e.g. people in the street stopping certain passers-by, questionnaires sent to a sample of homes) and sales figures can help to achieve this. •Can target reasoning and strategy making e.g. buy more of a certain commodity because sales are good. Advertising and marketing a product should be aimed at people likely to buy it otherwise it is a waste of time and money. •Gain advantage over competitors. Information can tell an organisation how well it is doing compared to its competitors. For example information can identify gaps in a particular market which can then, on the basis of sound information be filled. Cost of information 3 categories •Money •Time •Human resources Collecting the data Data entry Data collected directly The organisation or company has to produce a way of collecting information e.g. creating forms, questionnaires, sampling etc. In the case of forms and questionnaires, these will have to be printed, sent out and collected. Not all people respond to forms or questionnaires so many more will have to be sent out in order to get a fair sample back. Often, an incentive is given to encourage people to respond e.g. your name being entered into a free prize draw if the form is completed and returned. Data collected indirectly The organisation may have to buy the information or pay a third party to gain access to data. Keying in Data keying takes time and staff will have to be paid to do it. Direct input There are automated methods of data entry - optical mark readers (OMR), optical character recognition (OCR), bar code readers, etc. Specialised hardware/software needs to be purchased and staff trained to use them. Data processing Once the data has been inputted it needs to be processed into information. This requires hardware and software resources. The software may be ‘off the shelf’ or it may have been developed specifically for the organisation or company. Either way it will cost money. Data maintenance There are costs involved in making sure that data remains accurate and up-to-date. For example, an organisation maintains a database of its customers. The database will only remain accurate and up-to-date if changes to customers’ details are reported and then updated. This involves communication with customers and checking that their details are correct. Methods used include: The task of keeping data up-to-date is expensive. frequent updating (typing in the changes) frequent collecting of data through questionnaires, letters or checksheets interactive systems where a person can update his/her own detail deleting out-of-date data or data which is no longer needed making sure that all copies of the data are updated so that everyone uses the same, amended data. Example 2 It is no good having a mailing list when the addresses are no longer correct. When people move house, mail continues to be sent to the old address until the relevant mailing list is updated. Companies who sell their products through direct mail (junk-mail is the more commonly used name!)need up-to-date lists of names and addresses of people who are likely to be interested in their product. An out-of-date list is of no value whatsoever. Remember people move house, grow old, die, and change their interests or buying habits. Errors on data entry Verification is the process of checking that data has been correctly copied from one media to another. Visual checking for errors. Double entry keying Types of errors that can be found; •Transcription /typing errors Typing in the wrong character by accident egg 2 instead of a 7 •Transposition Errors i.e. keying in, in wrong order e.g. 56789 instead of 57689 Validation is the process of ensuring data is valid and legal. •Format checks e.g. date is 2002/ 09.11 instead of 11/09/02 •Input masks e.g. entering data in a controlled way Postcode if LLNN NLL •Input mask on a date 99/99/99 Validation type Explanation Example Range checks Data is between stated ranges Admission No must be between 1 and 9999999999 Format checks Dates 12/04/03 Presence checks There must be a character present ina particular place e.g. the first 2 letters must be YR to represent year YR7 Check digits No added to a code Bar codes on library tickets Date of birth Format checks 12/09/95 Range check between 1/9/86 – 31/8/94 Input masks 99/99/9999 Admission no Library code Presence check e.g. YGA 123454 ( must start with YGA) Check digit Gender M or F Advantages of using ICT • • • • • Speed of processing Accuracy of processing of repetitive tasks Fast transmission speeds Different output formats graphs reports etc Save and edit work in future Factors affecting the efficiency of use of ICT • GIGO • Suitability of hardware and software for task • Level of user ability • Changes in circumstances of during development of the computer system • Poor implementation and maintenance procedures • Cost restrictions on solution HCI’s • GUI’s Windows Icons Menus pointer, online tutorials – good for inexperienced user . Children. • Dos text based has short cut keys- expert user • Menu driven when want to limit choices • Voice • Specialists e.g. touch sensitive Flatfiles vs relational databases Database –A large collection of related files of data items and links between them, structured in a way that allows it to be accessed by a number of different applications programs. File –a collection of related records Records –The basic unit of data stored in a data file. –It is a collection of items which may be different data types, all relating to the individual or object the record describes. –It is treated as a unit for processing. Fields –Is part of a record designed to hold a single data item of a specified type. –Holds data items of the same data type Primary Key –It is a unique value which is used to identify a record. Members Bookings Staff Members Bookings Members Staff Staff Flatfile Relational database Advantages Disadvantages Minimise s data duplication More expensive to create Ensures data consistency DBMS needs full time maintenance Ensure data integrity Controls data redundancy Computer Assisted Learning (CAL) Tutorials Special needs pupils; Spelling programs which have an interactive component testing student with games, quizzes and tests. A scoring system allows students to assess their progress. Often after 3 tries the answer or clues will be given to them. Picture and sound are used to enhance the experience. GCSE revision programs DISTANCE LEARNINGStudents not always be in the same place as the teacher. Distance learning course where the tutor is in North Wales. Students are provide with course booklets and practical work and videoconferencing is used to discuss problems that ariseAssignments are marked electronically. Online courses e.g Open University These can be intranet based in universities or Internet based. Some university modules are completely computer based with knowledge sections and task sections. The software records how much of the course you have covered and if you do not complete the full module you will fail the module.. E – learning sites are now available. Subscribers can even do A levels online approved by exam board such as OCR. Schools in England are given E-learning credits which they can use to purchase online courses. Chat rooms to discuss courses and problems with tutors. Advantages of using ICT FOR TEACHING AND LEARNING • • • • • • Greater interactivity holds a pupils attention. Quicker feedback in online tests Offers a variety of different ways to learn and a variety of information sources. Allows user to learn at own pace and can learn at times suitable for themselves. Allows user to ‘go over’ earlier work again in case they did not understand i.e repeat sections they found difficult earlier. Computer based training significantly reduces costs for the employers and can be safer if it is a danger Advantages of using ICT FOR ADMINISTRATION • Improved speed of access to data - faster searches/ e.g looking for all the pupils in a particular form and faster sorts e.g. listing pupils by alphabetical order of Surname. • A variety of output formats available e.g. printed reports, mailmerged documents. Etc. – Faster and simpler to transfer data e.g. exam entries • Saves time when reproducing standard letters e.g. lettes to parents informing them about parents evenings, school sports day programs. Such documents will only have minor changes each year. • Increased security • Saves on storage/office space Problems with using ICT in Education ICT is expensive and requires a great deal of capital investment which is constantly updated and has to be maintained. Maintenance contracts can run into thousands of pounds which takes money away from traditional teaching materials such as books. Unfair distribution of ICT resources and hence learning opportunities. Richer schools will have greater resources. Cuts down on social interaction skills Some educationalists argue that younger pupils do not have as great an opportunity for group learning. Text messaging has been blamed for a reduction in spelling skills because of the use of abbreviations. Lack of personal support. Distance learning does not provide the personal support needed by most students as and when they need it, particularly crucial when a student lacks confidence or cannot interpret the written instruct Over reliance e.g. if there is a power cut you cannot use it. Wordprocessing / DTP Editing Alter text and graphics and save Formatting Text styles, paragraph styles, bullets etc Templates Master documents which are stored have predefined layout e.g. letter headed notepaper Style sheets Have predefined indents, tab settings and subheading styles Spreadsheets Graphs Easy to read data in graph form than in lists or tables. Instant transfer understanding Templates Saves redoing layout for a firm spreadsheets each time.Standardises image. Statistics Use of commonly used standard functions such as SUM AVERAGE etc saves time Presentation Software •Templates Background styles and themes with each slide being the same as the master slide. Has same logo colour scheme layout etc •Animated transitions Movement and direction of text and picture. Graphical display when moving from one slide to another •Formatting Use of font styles and sizes bullet point scheme for headings and subheadings Web Authoring • Frames to work in and control layout • Hyperlinks to other web pages • Hotspots are hyperlinks on graphics/ pictures to other web pages or other parts of the web page • Bookmarks are hyperlinks internally to other parts of the web page • HTML language code for creating web pages CAD Computer Aided Design Feature Definition Advantage Hatching or rendering Different finishes or materials can be dispalyed Can do many ‘what if ‘ type investigations to explore the best finishes Zoom Enhance parts of a drawing to make it bigger To produce work of more detail or add detailed design Rotate Rotae in 3D across X Y and Z axis See design from all angles on the outside Walkthrough Visit rooms etc in 2D Allows spatial awareness of what the design looks like in relation to other features Costings Produce estimate of cost of building materials Automatic estimates are given and designer can investigate different options or work within a budget. Stress and strain Working out the weights materials can take Avoids disasters later on when building as the designer should build well within the safety requirements Wire drawings See design without any finiahes or solid form Helps with perspective and working out stresses and strain areas Hazard Prevention RSI repetitive strain injury caused by prolonged working at computers or computer games Ergonomic keyboards ; wrist and foot supports: correct chair positioning Eye Strain and epileptic fits Non flickering screens; Screen filters t remove glare; correct lighting in the room Back problems Adjustable chairs; foot supports:; tilting screens Ozone irritation from laser printers Locate personal laser printer 1 metre away from user Radiation affects embryos leading to miscarriages No real evidence for this Expert Systems • An expert system is a computer system which emulates the decision-making ability of a human expert. • A knowledge-based system which attempts to replace a human 'expert' in a particular field. • It diagnoses problems and gives advice on that the cause of those problems are. They can also give advice on solutions. Medical diagnosis The computer does not take the place of the doctor but can be used to help the doctor make decisions. An expert system would have information about diseases and their symptoms, the drugs used in treatments etc. A patient is asked by a doctor about symptoms and the replies are input to the expert system. The computer searches its database, uses its rules and makes suggestions about the disease and its treatments. Sometimes probabilities are assigned to diagnoses. Advantages. • • • • • • • The computer can store far more information than a human. It can draw on a wide variety of sources such as stored knowledge from books case studies to help in diagnosis and advice. The computer does not 'forget' or make mistakes. Data can be kept up-to-date. The expert system is always available 24 hours a day and will never 'retire'. The system can be used at a distance over a network. So rural areas or even poorer third world countries have access to experts. Provides accurate predictions with probabilities of all possible problems with more accurate advice. Some people prefer the privacy of talking to a computer. Limitations /Disadvantagesof expert systems • • • • • • Over reliance upon computers Some ‘ experts’ could loose their jobs or not be given training if computers are available to do the job. Lacks the 'human touch'! – lack of personal contact Dependent upon the correct information being given. If data or rules wrong the wrong advice could be given. Expert systems have no "common sense". They have no understanding of what they are for, nor of what the limits of their applicability are, nor of how their recommendations fit into a larger context. If MYCIN were told that a patient who has received a gunshot wound is bleeding to death, the program would attempt to diagnose a bacterial cause for the patient's symptoms. Expert systems can make absurd errors, such as prescribing an obviously incorrect dosage of a drug for a patient whose weight and age are accidentally swapped by the clerk. Shopping Input devices Output devices Storage devices Processes for automatic stock control Benefits of automatic stock control Benefits of e commerce Disadvantages of using computer based shopping systems. •Do not tell anyone your password •Change password regularly •Virus scan all discs •Do not misuse the Internet e.g email, chat rooms •No hacking •Do not steal hardware / software •Hacking The Computer Misuse Act 1990 •Blackmail using •computer •Spreading a virus The Copyright Act Illegal to copy software •Illegal copying : -software piracy •Purchasing one legal copy and loading it into several computers memory •Downloading software over the Internet creating a copy. The Data Protection Act People were worried that; Being asked for data which was irrelevant to the purpose e.g. What is your religion ? Demand to see data and have it corrected Must have good security passwords etc. Justify and register why they need that data Length of time data was held on computer about them Get rid of any unused data when finished with Data given for on purpose e.g. medical data was being sold on to companies who produce mailing lists for junk mail. Not allowed to sell data on. Data was wrong Hacking into personal data 1. Personal data shall be kept up to date and accurate . 2. Personal data obtained lawfully only for one purposes must not used for another 3. The data must be relevant to the purpose for which it is given 4. Personal data shall not be kept for longer than is necessary 5. It should be kept secure against unauthorised access and loss 6. Personal data shall not be transferred to a country outside the EEC Exemptions on data 1. Personal data required by the Inland revenue 2. Personal data used by national security or a solicitor in a legal case 3. Personal data kept by the user on himself or family e.g. files on birthdays, addresses etc.