Chapter 1

Chapter 1

1. Data, Information, Knowledge, Processing

   • Definitions
     • Data
       • Raw facts and figures that have no meaning, meaningless. Examples include 090909, FDKA021.3
     • Information
       • Processed data that means something
     • Knowledge
       • The application of information to a situation
     • Processing
       • Performing an action on the data;sorting, searching or editing the data
   • Turning Data into Information
     • INFORMATION=DATA+[CONTEXT]+[STRUCTURE]+MEANING
     • Data=14123, Context=UK£, Structure=nnn.nn, Meaning, £141.23 in bank

2. Representation Methods

   • Text
     • Clear to understand, lots of detail
     • Ability to read, language barriers, time consuming
   • Graphics
     • No language barriers
     • Directional, confusing if symbols not understood
   • Sound
     • No fixed position, no sight required
     • Can be distorted, language based, hearing abilitty
   • Animation
     • A lot of information, not language based
     • Linear, problems if sound dependent, need to be able to see
   • LED
     • Secure data, noisy places, similar to graphics
     • Directional, combinations need to be known

3. Data

   • Data Types
     • Integer
       • Whole numbers, 42
     • Boolean
       • One of two values, Yes/No
     • Real
       • Decimals, 12.6
     • Date/Time
       • Numbers and letters, December '12
     • String
       • Alphanumeric, telephone number
   • Data Sources
     • Static
       • Does not change
       • Limited information, not quickly updated
       • Does not need internet, more reliable
     • Dynamic
       • Can change
       • Need internet, not always reliable
       • Large volume of information, updated quickly
     • Direct
       • Physically collected by user
       • Source is known, can be changed
       • Not a large range, not always available
     • Indirect
       • Collected by someone else, used for a different purpose
       • Large range of data, data from different locations
       • Could be bias, not certain of accuracy

4. Quality of Information and Encoding

   • Accuracy
   • Relevance
   • Age
   • Level of detail
   • Completeness
   • Presentation
   • Encoding
     • Less memory required, higher level of security
     • Precision of data coarsened, codes need to be known

5. Validation and Verification

   • Ensures data is reasonable, sensible and within boundaries of rules
     • Range check
     • Type check
     • Presence check
     • Length check
     • Look-up
     • Picture check
     • Check digit
   • Ensures data is entered correctly
     • Errors
       • Transcription; miscopied
       • Transposition; numbers/letters round wrong way
     • Double-Entry
       • Compares two sets of manually entered data and informs user.
       • If same mistake made twice then it wont be picked up
     • Proof Read
       • Paper copy compared with on-screen copy
       • Difficult to transfer between paper and screen

6. Input, Processing, Output, Storage and Feedback

   • Input
     • Entering into the system, manual/electronic
       • Ticket request
   • Processing
     • Action performed on data
       • Search to find tickets
   • Output
     • Outputting the input data
       • "No tickets"
   • Storage
     • Where the data is held
       • Details of request
   • Feedback
     • Output forms part of the input back into the system
       • Put on waiting list for more tickets

7. Costs of Producing Information

   • Software
     • Graphics, DTP, OS
   • Personnell
     • Wages, training
   • Consumables
     • Paper, ink,
   • Hardware
     • Repair, storage, maintenance

8. Back-up and Archiving

   • Back-up is a copy of data and can be used to restore it. Stored on removable media and taken to another location
   • Archiving is moving data which is used for long term storage and for data that is not immediately required.