Double entry verification
Two sets of data are entered and then compared, more expensive and time consuming but more accurate
Records information and inputs it at times and in locations where it would be difficult for a person to do it
Radio frequency identification (RFID)
Microchips that store information and can be read wirelessly
An extra digit added to a number that is calculated in a prescribed way that is known to the computer system, the check digit is then checked
Many factors influence output design. One very important constraint is that output is dependent on the availability of the data it is derived from. If this is not already stored within the lCT system when output is requested, then the required Output cannot be generated .
Audience, Usage of Tables, Diagrams, Graphs, Layouts, Timing and Accessibility. Use simple language to avoid the audience from being confused.
This type of output is produced for the external audience but it is expected that they will add data to it and return it to the organization. An example of a turnaround document is Cl printed questionnaire or data capture form.
Use of Tables, Diagrams and Graphs
Tables. diagrams and graphs can be used to summarize information. They should
be clearly labeled. with legends provided for all abbreviations.
A pie diagram gives us information about relative importance of the takings from the sales of the different types of meals.
You could set up a validation check to make sure that only 'F' or 'M' were entered. Similarly 'Male' and 'Female' could easily be validated if this was being entered in an interactive form on a website.
Codes can be used to represent lengthy snippets of language. It can be found in our everyday devices from mobile phones to laptops and cars!
Examples of Encoding Data
'1' could mean 'Can you switch the television on?'
'2' could mean 'Which channel would you like to watch?'
'3' could mean 'I'd like to have pasta for dinner!'
Why is a range check for dates important?
As if there isn't a boundary then the numbers may be incorrect and invalid.
What are an advantage and a disadvantage for double entry verification?
One advantage is that the data will be almost 100% correct, one disadvantage is that this type of checking takes much longer.
Why are codes used?
They are used because:
-Data entry is easier.
-Data entry is faster.
-Less space is needed to store the data on backing storage.
-Setting up validation checks is easier.
-Privacy can be preserved.
-Output can be more concise.
Example of using codes
Codes are widely used in ICT systems. Another example would be a database for a school library where books are classified as 'fiction', 'non-fiction' or 'reference' and there are other resources like 'CDs', 'DVDs' and 'Magazines' that can be borrowed.
Coding these as 'F', 'N', 'R', 'C', 'D', 'M' would speed up data input, reducing the space needed on backing storage and make output more concise.