2.2 Data And Information

Question 1

Data

Answer 1

Raw facts and figures not been processed or given context

Question 2

Information

Answer 2

Data that has been given meaning by processing or putting in context

Question 3

Knowledge

Answer 3

When humans apply rules to information

Way to make decisions and way to interpret information.

Question 4

Factors affect quality of information

Answer 4

Accuracy 
Relevance 
Currency 
Completeness 
Reliability 
Presentation

Question 5

Data validation

Answer 5

Length check
Presence check
Format check
Check digit

Question 6

Type check

Answer 6

Confirms if a piece of data is a certain type

E. G. Price values must be currencies

Question 7

Format check

Answer 7

Check if pattern or sequence of characters that have been entered are correct.

Question 8

Evaluate check digit

Answer 8

Advantages
Checked automatically
Processed fast

Disadvantages
Input barcode- input inaccurately
Only useful for numeric data

Question 9

C+C hash and control totals

Answer 9

Both only apply to batches of data
Both worked on in advance.

Control total creates information that has a useful meaning in itself.
Hash total creates information which has no instrinct value.

Question 10

How control total preferable to a hash total when validating input of following data
Candidate numbers and exam scores for 100 pupils

Answer 10

Control total preferable- information it creates is useful as it has a meaning in itself.
Eg. Adding up all the scores is useful info.

Hash total would mean information has no instrinct meaning.
Eg. Adding up the value off all candidate numbers in an exam which no one would ever need to know.

Question 11

Two differences between data validation and data verification

Answer 11

Data verification is an attempt to ensure that data is consistent with its source and hasn’t been corrupted.

Involves using double entry and proof reading to ensure data is correct
Human has to proof read or re enter.

Data validation ensure data is sensible, reasonable, within boundaries and complete.

Involves using number of checks eg. Length and presence check. To make sure data is correct.
Automatic on data entry.

Question 12

Evaluate use of data validation and verification when inputting following data.
Candidate numbers and exam scores for 100 pupils.

Answer 12

Useful in ways to ensure that data entered is correct and feasible.

Using data validation on the candidate numbers and exam scores will ensure while data is being entered it is the correct data.
Type check we can ensure that data entered Is of right type e. G. Candidates numbers are numbers.
Presence check useful as ensures nobody’s grade is left blank.

Verification- e. G. Proof reading- allows user to confirm they have read data to check its accuracy.
Helpful as it means that user can enter correct data and makes less mistakes when entering data.