Data Validation and Verification Review

Data Validation and Verification Review

Main types of errors:

• Transcription error: typographical mistakes/ the wrong character- letter or number was entered

  
  

• Transposition error: the characters- letters or numbers were interchange or put in the wrong place

Multiple Select

Dale, a data entry clerk, is entering data from a paper-based form into the computer system. Identify two types of errors that can occur.

• Transposition error

• Presence error

• Transcription error

• Range error

Visual Verification Checks

• Double entry

• Proofreading

• Print a copy of the data and comparing with original paper document 

• A second person read the input data while the first checks against the original document 

• Checking the data on the screen against the original paper document

Multiple Select

To help ensure he entered correct data, David can use the following two verification checks:

• range check

• proofreading

• consistency check

• double entry

Validation Checks

• Data type This check ensures that data entered is of a specified type before it’s accepted

• Range Check: check ensures that data entered fits within a particular range.

• Consistency Check: ensures that data in one area cross references logically with data from another area

• Presence Check: This check ensures that data is actually entered in a field and it is not left blank.

• Parity Check ¨This check ensures that data is not adjusted (via electrical interference) during transmission...

• ...It adds an extra bit (0 or 1) to make the total number of ones (in a byte) odd or even.  

Multiple Select

David has to enter the age of students attending secondary school into one of the fields. identify three validation checks that can be applied to the age fields

• parity check

• range check

• data type check

• presence check

• double check