Data, Information, Knowledge & Processing

Data, Information, Knowledge & Processing

1. Data, Information & Knowledge

   • Data
     • Raw facts and figures with no meaning.
     • e.g. 180596
   • Information
     • Information = Data + [Structure] + [Context] + [Meaning]
       • Structure - how the data is presented.
         • e.g. 18/05/96 is a UK date.
       • Context - an environment where our prior knowledge and understanding can make sense of the data.
         • e.g. 180596 is a birthday.
       • Meaning - data in the correct structure and within the context.
         • e.g. 18/05/96 is my birthday.
     • Processed data.
   • Knowledge
     • The application of information to a situation.
   • Information vs. Knowledge
     • Information based on facts. Knowledge is opinion.
     • Information can be quantified and judged against. Knowledge can be quantified with success criteria.

2. Representation Methods

   • Text
     • Advantages
       • Clear to understand.
       • Lots of detail.
     • Weaknesses
       • Need to be able to read.
       • Not multilingual.
       • Lots cannot be read quickly.
       • Level of language can be confusing.
   • Graphics
     • Advantages
       • Multilingual.
       • Can match what you see - physical shapes.
     • Weaknesses
       • Need to know symbols.
       • Symbols are not universal.
   • Sound
     • Advantages
       • No fixed position.
       • No line of sight required.
       • Good for visually impaired.
     • Weaknesses
       • Not good in large areas.
       • Usually language based.
       • Need to be able to hear.
   • Moving Pictures
     • Advantages
       • Lots of info conveyed.
       • Not language dependent.
       • Can exemplify text.
     • Weaknesses
       • Linear - if you miss the beginning you may not understand.
       • Problems if sound attached.
   • LED
     • Advantages
       • Can allow data to be kept secure.
       • Can be used in noisy places.
       • Similar to graphics.
     • Weaknesses
       • Need line of sight.
       • Combinations need to be known to be understood.

3. Data Types

   • Boolean
     • Can contain 1 of 2 values.
     • e.g. Yes/No
   • Real
     • Numbers with decimal places.
     • e.g. 12.3
   • Integer
     • Whole numbers.
     • e.g. 123
   • Text/String
     • Alphanumeric characters.
     • e.g. ME2 3QZ or "Hello".
   • Date/Time
     • Contains numbers and letters, which depending on the format display the date/time to different degrees of accuracy.
     • e.g. 1996

4. Sources of Data

   • Indirect vs. Direct
     • Indirect
       • Data used for purpose other than what it was originally collected for.
       • Data collected by a separate party.
       • Advantages
         • Large range of data available which couldn't be collected directly.
         • Data available from different locations and time periods.
         • Analysis might have already been completed on some data.
       • Weaknesses
         • Don't know if bias placed on collection.
         • Can't be certain of accuracy of recording.
         • May not have all info on how and when collected to make a valued opinion on usefulness.
         • Info may not have been originally collected and so are unable to get hold of it.
     • Direct
       • Data collected from an original source.
       • Advantages
         • Source and collection method is known and verified.
         • Exact data required can be collected.
         • Data collected can change in response to answers.
       • Weaknesses
         • May not get large range of data.
         • Data may be unavailable - location/time.
   • Static vs. Dynamic
     • Static
       • Once created data does not change.
       • e.g. CD ROM
     • Dynamic
       • Information is able to be updated.
       • e.g. Websites
     • CD ROMs vs Websites
       • CD ROMs
         • Advantages
           • Does not require internet access.
           • More reliable source of information.
         • Weaknesses
           • In a single location.
           • Limited amount of info available.
           • Data cannot be updated very quickly.
           • Can be scratched or broken.
       • Websites
         • Advantages
           • Large volume of info.
           • Updated quickly.
           • Same web resource can be accessed from anywhere if address is known.
           • Accessible 24/7.
         • Weaknesses
           • Info is not always reliable.
           • Need internet access.
           • Need correct browser software.

5. Quality of Information

   • Accuracy
     • If inaccurate you cannot rely on information, lower quality.
   • Relevance
     • If irrelevant it can't be used for that topic, lower quality.
   • Age
     • Information can change over time, old information has lower quality.
   • Completeness
     • If only part of the information it cannot be used, lower quality.
   • Presentation
     • If can't understand layout, lower quality.
   • Level of Detail
     • If too much information is given it takes too long to find necessary info, lower quality.
     • If not enough info is given wont have enough to make a decision, lower quality.

6. Encoding Data

   • Taking the original data and storing it in a different representation.
   • Advantages
     • Lower memory requirements.
     • Quicker to input.
     • Can apply validation.
   • Weaknesses
     • Need to know code.

7. Validation Methods

   • Range check
     • Upper and lower bound.
   • Type check
     • Presence check.
   • Length check
     • Set number of characters.
   • Lookup check
     • Compares value against list of valuesin a different table.
   • Picture check
     • Format can be checked e.g. LLNNLL for letters and numbers.
   • Check digit
     • Calculated set of numbers and added to the end of them.

8. Verification Methods

   • Double entry
     • Enter data twice, data is compared to previous.
   • Manual verification
     • Visually compacring data with source document.

9. Archiving and Back Ups

   • Back ups keep a copy of the current data.
   • Archiving is for long term storage that isn't required immediately.

10. Cost of Production

    • Hardware
      • Printers, monitors, etc.
    • Software
      • Licenses, operating systems, utilities, etc.
    • Personnel
      • Staff wages.

11. Feedback Loop

    • Input - taking info external to system and entering into system.
    • Processing - action performed on data.
    • Storage - where data is held.
    • Output - taking info from out of the system.
    • Feedback - output forms part of input to the system.