AS ICT - Chapter 1

AS ICT - Chapter 1

1. Data

   • Raw facts, unprocessed, no meaning

2. Information

   • Taking data and processing it, certainties

3. Representation Methods

   • Text
     • Adv: explanations, clear, read if noisy
     • Dis: language, long explanations, need to see
   • Pictures
     • Adv: no language, always there, ok if noisy
     • Dis: need to know signs, no explanations
   • LED
     • Adv: cheap, power efficient, little memory
     • Dis: meaningless, close to see them
   • Video
     • Adv: explanations, how to... videos
     • Dis: time consuming, hearing and visual, linear
   • Sound
     • Adv: grab attention, visually impaired, large area
     • Dis: hear, everyone can hear, there at time
   • Animation
     • Adv: convey actions, language dependant
     • Dis: only shows steps, no sound

4. Knowledge

   • Application of information to give understanding
   • It can change, add more info, based on rules

5. Data Types

   • Boolean
   • Real
   • Integer
   • String
   • Date/Time

6. Static and Dynamic Data

   • Static
     • Limited info, no internet, reliable, not updated quickly, need book/CD
   • Dynamic
     • Large volume, need internet, less reliable, updated quickly, access anywhere

7. Data Sources

   • Direct: collect for purpose and by you
     • Adv: correct data, trusted source
     • Dis: costly to collect, time to collect, small sample size
   • Indirect: different purpose, not by you
     • Adv: instantly available, sources compared, large sample size
     • Dis: not meet requirements, out of date, unreliable, no detail

8. Quality of Information

   • Accuracy
   • Age
   • Relevance
   • Completeness
   • Presentation
   • Level of detail

9. Validation

   • ensure data is sensible, reasonable, in acceptable boundaries, complete
   • Range check
   • Type check
   • Length check
   • Picture check
   • Prescence check
   • Lookup check

10. Encoding Data

    • Replaces data with shorter data
    • Speed up processing, less storage, more accurate, improve presentation, security

11. Verification

    • Reduces errors, checks data is transferred correctly
    • Double-entry
    • Proof reading
    • Errors if data entered incorrectly both times, incorrect data source, proof reader misses error

12. Backup and Archiving

    • Backup: copying the data to USB, CD-RW, online storage
    • Backup procedures: away from original data, regular backups, lots of versions, security
    • Archiving: move data to offline storage to CD-R, tape, more main storage, rarely needed

13. Costs of Producing Information

    • Hardware: equipment to collect/process info, maintenance
    • Software: purchase or rent e.g. word processing
    • Personnel: people involved in collecting data, produce info, train others
    • Consumables: something that is used e.g. paper/ink

14. Input, Process, Output, Storage and Feedback

    • Processing: data processed
    • Output: info output by system
    • Input: data input
    • Storage: data stored before/after processing, data retrieved
    • Feedback: output info affects input info