B061 4.0 Manipulating data

Question 1

Different types of data

Answer 1

Text/Alphanumeric
Numeric (Integer,Real numbers,Currency,percentages, Fractions)
Date and time
Boolean or Logical (yes/no open/closed Male/female On/off )

Question 2

Give examples of data collection

Answer 2

Questionnaires
Application forms 
Online forms  
Optical Mark Recognition 
Bar code readers
Biometrics
RFID tags

Question 3

What are the Advantages to OMR

Answer 3

It is a fast method of inputting large amounts of data at a very high rate

Only one computer needed ton correlate batch of data therefore lower cost

OMR is a more accurate method of data entry than manually keying data

Question 4

Disadvantages of OMR

Answer 4

The marks may not read correctly if spaces aren’t completely filled in

Not Suitable for text input ; mainly used for multi-choice input

Needs specially prepared stationary as well as a OMR reader also data needs to inputted into specific perimeters

Question 5

Advantages of barcode readers in electric point of sale situations

Answer 5

Automatic input therefore quick to enter

Bar code errors easily avoided via warning systems

Check digit software included

Easy to change data in databases and this allows for updates

Can be linked to stock control therefore allowing for a creation of an automatic re-ordering

Question 6

Disadvantages of barcode readers in electric point of sale situations

Answer 6

Other alternative methods needed in case system fails

If barcodes are missing data will need to be added manually

New products have to be added to the database otherwise the system would be out of date

Training required to use the hardware

Question 7

Advantages of Chip and Pin/ Magnetic Strip Recognition

Answer 7

Simple to use and cheep to produce

Data can be altered if necessary

Security has been improved by the use of PIN numbers which must be entered into a machine to confirm that you are the rightful card owner

Question 8

disadvantages of Chip and Pin/ Magnetic Strip Recognition

Answer 8

It has very limited storage capacity for data

Data can easily be destroyed by strong magnetic fields

It is not always secure as thieves can obtain the readers and read the data on the card

Question 9

Advantages of voice recognition

Answer 9

Quicker method of entering data than using using a keyboard

Ideal methods for disabled users who can’t easily use keyboards

Helps to prevent repetitive strain injury

Question 10

Disadvantages of voice recognition

Answer 10

Software needs to be trained to recognise an individual voice and accent accurate data entry

The user has to learn a range of commands and sometimes there are problems distinguishing between input text and commands

Excessive background noise can cause errors as the speech input is quality is reduced

Question 11

What is Biometrics recognition and how does it work

Answer 11

It is used to identify an individual by either Physiological such as finger prints iris recognition

Behavioral such as voice recognition

Question 12

What are RFID tags and how do they work

Answer 12

Radio frequency identification tags are fixed to products like barcode. They use the antenna to communicate with RFID reader or scanner for tracking purposes

Question 13

What is an Absolute cell reference

Answer 13

When a formula is copied from one cell to another may be a need to maintain an absolute cell reference with the original cells. This is can be achieved by referencing a cell as $A$1 which when copied will remain $A$1

Question 14

What are flat file Databases

Answer 14

A flat file database is a simple database that is composed of one table often used in the creation of spreadsheets each row is know as a record

Question 15

What are relational Databases

Answer 15

The data is stored in separate tables or entities
All the data tables are linked by key fields
Microsoft Access is an example of Relational Databases management systems

Question 16

List the verification types

Answer 16

Presence check 
Data Type check 
Length check 
Check Digits 
Range checks
Format Check

Question 17

Define Presence check

Answer 17

Checks that data has been entered into a field and that is has not been left blank

Question 18

Define Data Type check

Answer 18

Checks that a value entered is of a particular data type.

Question 19

Define Length check

Answer 19

Checks than an entered value such as mobile phones is no longer than a particular number of characters

Question 20

Define Check Digits

Answer 20

These are normally digits on a ISBN book code that are used as a part of a calculation to ensure that the code entered is valid code.

Question 21

Define Range checks

Answer 21

Checks that an entered value falls within a particular range

Question 22

Define Format Check

Answer 22

Check that an entered value has a particular format.

Question 23

what are the two mains ways to verify data

Answer 23

Visual checks

Double entry

Question 24

What is a Batch total in the context of Validation

Answer 24

This is a check for missing records where the all numerical records for a batch are summed together.

Question 25

What is a Hash total in the context of Validation

Answer 25

this a check used for detecting errors in data transmission. A hash total is calculated from several fields in a file or table before and after data transmission and a comparison is made between the original and final data to detect a difference or an error