Validation and Quality of Data

Question 1

What are Validation Checks?

Answer 1

Ensure that only sensible data is entered into a computer - validation checks are in every from you fill in the internet.

Question 2

Name 4 types of Validation checks

Answer 2

Range check, Format Check, Presence check and Check digit.

Question 3

What is meant by the term ‘Range check’

Answer 3

Checks that numbers are between a certain range e.g. a movie site would make you enter your date of birth if buying/renting 18-rated movies.

Question 4

What is meant by the term ‘Format check’

Answer 4

Correct mix of letters and numbers are entered. e.g. shopping sites may restrict postcodes to the following combinations of letters and numbers - LL00 0LL.

Question 5

What is meant by the term ‘Presence check’

Answer 5

Fields are not empty. e.g. When signing up for Facebook, Instagram etc, the username field must be filled in.

Question 6

What is meant by the term ‘Check digit’

Answer 6

An extra number added to the end of a longer set of numbers. Preforming a calculation on the longer set numbers.

Question 7

Gave an example of Transposition

Answer 7

Accidentally pressing Q instead of W.

Question 8

Give 2 ways to prevent these errors

Answer 8

Visually check - proofread.

Double -keying - entering it twice and checking both are the same.

Question 9

What happens if data isn’t good quality?

Answer 9

There is a danger of GIGO.

Question 10

Give 3 ways to have good data

Answer 10

Accuracy - Data must be true and correct.
Fitness for purpose - Data must me suitable for what you want it to do.
Bias - Should not favour a particular result.