TOPIC 1: Data, Information and Knowledge

TOPIC 1: Data, Information and Knowledge

1. Key definitions

   • Data
     • raw facts and figures collected from sensors and surveys.
     • Forms of data: words; numbers; sounds and images
     • no particular meaning or application
     • example
       • 21111998
   • Information
     • Data that has been processed
     • INFORMATION= DATA+ MEANING+ CONTEXT
     • e.g. 21111998 is a British date– 21/11/1998 (context). It is my birthday (meaning)
   • Knowledge:
     • Information that has had rules applied to it
     • e.g. 21111998 (Data) is a British date– 21/11/1998- and it is my birthday (Information). It is my birthday next week so I need to sort out my birthday party.
   • G.I.G.O
     • Means Garbage In Garbage Out.
     • – if you enter inaccurate data then you are going to get inaccurate results

2. Data

   • Good Quality Data
     • Up- to-date
     • relevant
     • fit for purpose
     • accurate
     • un- biased

3. Data VALIDATION checks

   • range check
     • Checks that he data is within a certain range
   • format check
     • checks that data has been entered in the right pattern
       • e.g. pattern for a postcode is LLN NLL
   • presence check
     • checks that data has been entered
   • check digits
     • is used to check that a series of numbers have entered correctly
       • the check digit is the last number in the sequence.
         • all the other numbers must equal that number after a complex calculation
           • . if they don't then a notification is brought up
   • validation checks make sure that data is sensible, reasonable, complete and within acceptable boundaries.
     • It DOES NOT check that the data is accurate
   • data type check
     • will check that the correct type of data has been entered

4. Data VERIFICATION checks

   • Visual check/ proof read
     • double check the entered data against the original source document and look for mistakes
   • double entry of data
     • when you type something in you have to type it twice
       • computer checks the first entry against the second entry
         • if there are any mistakes then a notification shows
   • parity checking
     • Even parity is checking that the number of 1's in the data word adds up to an even number
     • Odd parity is checking that the number of 1's in the data word adds up to an odd number.
     • adds an extra bit to each data packet. When an error is detected, a 'parity error' shows up.
   • hash totals
     • a specific item on the documents is chosen from the source document and a calculation is performed on it
       • the same calculation is performed on the entered data
         • if the answers do not match up then there has been a mistake
   • batch totals
     • checks that the correct number of documents have been entered by counting the number entered onto the system
   • checks that data is as ACCURATE as possible and checks that the data entered into the system is IDENTICAL to the original source document.

5. errors

   • Transcription
     • this is where the user has misread the original data or misheard what someone said over the phone
       • e.g. 'smyth' instead of 'smith'
   • Transposition
     • this is where the user has accidently changed the order of the characters
       • e.g. '98' instead of '89'

6. encoding