4.3.3 Human Computer Interface (HCI)

Question 1

state the factors that need to be taken into account when desinging a good user interface

Answer 1

• consistency of signposting and pop up information
• on screen help
• layout appropriate to task
• differentation between user expertise
• clear navigational structure
• use by disabled people

Question 2

• Give the names of the four factors that should be taken into account when desinging a HCI and for each factor describe why it is important (8 marks)

Answer 2

On screen help- rather than wasting time looking a manual important in case outside help is not available from other sources e.g wizards to take you through the task, tool tips tells user what to do

Clear navigational structure- it should be clear for users how to get to the next step or next screen and navigational features (e.g Next, forwards and backward arrows) should be positioned in the same place through the progrms, speeds things up if there is a simlar route and helps users learn their way through the system

consitency of signposting and pop up information- every next should be in the same place using the same icon, so that interface is intuitive, which makes the software easier to learn

Expertise of the user-
expert user will need shortcuts so that the task can be completed as quickly
novice will need a number of steps to guide them

customisable to suit the needs of the user- make it more efficient if the user can change items to suit their work preference change font size

Use by disabled people- if a person is blind then the use of a ‘talking’, where the words are spoken when typed in by the user computer is helpful Or if they are colour blind they change colours to avoid the red/green combination

Layout appropriate to task- experts may prefer to type in commands rather than use a mouse, less experienced users will prefer to use the mouse and GUI as they don’t have to learn commands

Question 3

*An expert user and a novice user have differing needs when using ICT.
Explain what these differing needs are and then describe how HCI can be desinged to satsify these needs

Answer 3

Needs of the users:
expert- will want to get the job done in the shortest possible time
novice- user’s priority wil be the ease of learning/intuitive

How these needs could be met:
expert-
1. often type at high speeds and can memorise key commands, this faster than using a mouse and clicking icons
2. should be able to customise interface to suit their needs
3. increase the number of ways to perform the same operation, e.g an expert would want to press in Ctrl+P to print, instead of using menus or icons

novice-

1. provide tutorials
2. step by step approach; they should never be left wondering what to do next; wizards can help with this
3. novice users like a mouse/ gui
4. clear navigational structure, colour scheme making it easier to use i.e showing outes through a program (hyperlinks)

Question 4

*describe using examples the features of a HCI that would help a disable person use a computer

Answer 4

• Visually impaired people can have their screens configured using large
  fonts.
  -Visually impaired people can also use special Braille keyboards to enter the data and can use Braille printers to produce output which other blind people can read.
  -Use of correct colour schemes for colour blind people.
  -Magnify areas of the screen for people with poor eyesight.
  -Visual messages on screen instead of sound for the deaf.
  -Use large mouse or trackerball for people with poor co-ordination.
• Blow pipes (sip and puff switches) or eye movements for entering text
  controlling devices for those who cannot use their arms, etc.
  -Brainwave controlled devices for physically handicapped with no
  arm/hand movement.

Question 5

*Describe the factors that should be taken into account when deisning an appropriate HCI thst would be used by a young child learning how to spell

Answer 5

-Have a minimum amount of text on screen
-Use child friendly font/size of font (NOT Text)
-Use bright colours to attract the child’s attention
-Have an uncluttered appearance
-Involve minimal use of the keyboard / alternative input devices
-Use speech synthesis / sound so that they can hear the words
-Animation/videos to keep their interest
-Instant feedback on their responses
-Interactivity e.g. quizzes, educational games (must have an example)
-Visual prompts e.g. pictures of a cat (must have an example or
justification/reason)