Learnability 2

Question 1

Interaction Style 1: Command Language

Answer 1

• User types commands in an artificial language
• Earliest
• Knowledge in head
• Not easy to learn

Question 2

Interaction Style 2: Menus and Forms

Answer 2

• UI presents user with menus and forms
• GUI including menu bars and dialogue boxes
• Knowledge in world
• Easy to learn

Question 3

Interaction Style 3: Direct Manipulation P1

Answer 3

• User interacts with visual representation of data objects
• Continuous representation of graphical objects, icons and text
• Continuously displayed, not displayed on demand
• Contrast to command language style text editor

Question 4

Interaction Style 3: Direct Manipulation P2

Answer 4

• Physical actions
• Clicking
• Dragging
• Not every function is easily mapped e.g. making text bold command is trigged by pressing a button and thats analogous to pressing a physical button

Question 5

Interaction Style 3: Direct Manipulation P3

Answer 5

• Effects: RIRI, rapid, incremental, reversible, immediately visible
• Actions can be undone
• Scroll bar can be dragged a little or a lot and incremental change will be seen

Question 6

Why Direct Manipulation is so powerful?

Answer 6

• Exploits perceptual and motor skills of human machine
• Depends less on linguistic skills in IS 1 and 2
• More natural because we learnt how to manipulate the physical world before we could talk, walk and read

Question 7

Interaction Style 3: Speech Dialogue

Answer 7

• User speaks in natural language and system responds the same way
• Once province of researc
• Now in a lot of applications
• Leans on knowledge in the head
• Users need to learn what can be said

Question 8

Using multiple Interaction Styles

Answer 8

• Real user interfaces often combine multiple interaction styles to make up for deficiency in one style

Question 9

Models

Answer 9

• Learning a new system requires the user to build a mental model of how the system works
• Learning can be effected by difficulties in building that model
• Model of a system: how it works
• Facebook model is at a high level

Question 10

3 Models in UI design

Answer 10

• System Model: how the system actually works
• User Model: how the user thinks the system works
• Interface model: the system presented to the user through the UI

Question 11

Interface Model should be:

Answer 11

• Simple
• Appropriate
• Well Communicated

Question 12

Consistency

Answer 12

• A general principal of learnability
• User shouldn’t be surprised with the way a command works: similar things should look and act the same, different things should look different
• Consistency allows user to transfer their knowledge to different UIs

Question 13

Internal And External Consistency

Answer 13

• Internal: Within application

- External: WIth other applications