Human-Computer Interaction Module 2.2

Question 1

When you’re designing for learnability, you have to be aware of ____________________

Answer 1

How people actually learn

Question 2

The conventional model for human memory has two components:

Answer 2

Working Memory and Long-term memory

Question 3

This memory is where you do your conscious thinking.

Answer 3

Working Memory

Question 4

This memory is probably the least understood part of human cognition.

Answer 4

Long-Term Memory

Question 5

This is the act of repeating the items to yourself, which fends off this eventual decay of working memory, but doing this requires attention. So, distractions can easily destroy working memory.

Answer 5

Maintenance Rehearsal

Question 6

The elements of perception and memory are called

Answer 6

Chunks

Question 7

In one sense, chunks are defined ________; in another sense, a chunk represents the _______________.

Answer 7

symbols; activation of past experience.

Question 8

Our ability to form chunks in working memory depends strongly on how. . . ?

Answer 8

the information is presented.

Question 9

This is remembering with the help of a visible cue

Answer 9

Recognition

Question 10

This is remembering something with no help from the outside world.

Answer 10

Recall

Question 11

We can think about __________ (and __________ and _________) in terms of a generalized cognitive model for how people use a computer system

Answer 11

learnability, visibility, efficiency

Question 12

This has been one of the major goals in the evolution of graphical user interfaces over the last few decades.

Answer 12

Better learnability

Question 13

The earliest computer interface

Answer 13

Command Languages

Question 14

This interface presents a series of menus or forms to the user.

Answer 14

Menu/Form Interface

Question 15

the preeminent interface style for graphical user interfaces.

Answer 15

Direct Manipulation

Question 16

Direct Manipulation is defined by three principles

Answer 16

A continuous visual representation; Physical actions or labeled button presses (clicking on virtual objects and manipulating them via drag and drop type actions); The effects of actions should be rapid, incremental and reversible.

Question 17

Why is direct manipulation so powerful?

Answer 17

It exploits perceptual and motor skills of the human machine – and depends less on linguistic skills than command or menu/form interfaces. So it’s more natural in a sense, because we learned how to manipulate the physical world long before we learned how to talk, read, and write.

Question 18

3 Types of Interaction Styles

Answer 18

Command Language, Menu/Form Interface, Direct Manipulation

Question 19

Comparison of the interaction styles in terms of Learnability?

Answer 19

CL requires significant learning. Users must put a lot of knowledge into their heads in order to use the language, by reading, training, practice, etc. The MF style puts much more information into the world, i.e. into the interface itself. DM also has information in the world, delivered by the affordances, feedback, and constraints of the visual metaphor. Since recognition is so much easier than recall, this means that MF and DM is much more learnable and memorable than CL.

Question 20

Comparison of interaction styles in terms of Error messages?

Answer 20

CL and MF often have error messages (e.g. you didn’t enter a phone number), but DM rarely needs error messages. There’s no error message when you drag a scrollbar too far, for example; the scrollbar thumb simply stops, and the visual constraints of the scrollbar make it obvious why it stopped.

Question 21

Comparison interaction styles in terms of efficiency?

Answer 21

Experts can be very efficient with CL, since they don’t need to wait for and visually scan system prompts, and many CL systems have command histories and scripting facilities that allow commands to be reused rather than constantly retyped. Efficient performance with MF interfaces demands good shortcuts (e.g. keyboard shortcuts, tabbing between form fields, typeahead). Efficient performance with DMs is possible when the DM is appropriate to the task; but using DM for a task it isn’t well-suited for may feel like manual labor with a mouse

Question 22

Comparison of Interaction styles in terms of User Type

Answer 22

CL is generally better for expert users, who keep their knowledge active and who are willing to invest in training and learning in exchange for greater efficiency. MF and DM are generally better for novices and infrequent users.

Question 23

Comparison of Interaction Styles in terms of Sychrony?

Answer 23

Command languages are synchronous (first the user types a complete command, then the system does it). So are menu systems and forms; e.g., you fill out a web form, and then you submit it. DM, on the other hand, is asynchronous: the user can point the mouse anywhere and do anything at any time. DM interfaces are necessarily event-driven.

Question 24

Comparison of Interaction Styles in terms of Programming difficulty?

Answer 24

CL interfaces are relatively easy to implement. MF interfaces have substantial toolkit support; e.g., it’s easy to create an MF web site using plain vanilla HTML, or an MF Java program using nothing but Java Swing widgets like textboxes, buttons, and checkboxes. DM is hardest to program

Question 25

Comparison of Interaction Styles In terms of Accessibility?

Answer 25

CL and MF interfaces are more textual, so they are easier for vision-impaired users to read with screen readers. DM interfaces are much harder for these users.

Question 26

Regardless of interaction style, learning a new system requires the user to. . .?

Answer 26

Build a mental model of how the system works.

Question 27

A _____ of a system is a way of describing how the system works.

Answer 27

model

Question 28

Models in UI Design

Answer 28

System (Implementation) Model, Interface (Manifest) Model, User (Conceptual) Model

Question 29

This model is how the system actually works.

Answer 29

System model

Question 30

This model is the model that the system presents to the user through its user interface.

Answer 30

Interface Model

Question 31

This model is how the user thinks the system works

Answer 31

User Model

Question 32

. Learnability Principles

Answer 32

Affordances, Natural Mapping, Visibility, Feedback, Consistency

Question 33

This refers to the perceived and actual properties of a thing, primarily the properties that determine how the thing could be operated.

Answer 33

Affordance

Question 34

They are how an interface communicates nonverbally

Answer 34

Affordances

Question 35

Mapping functions to controls

Answer 35

Natural MappingE

Question 36

Examples of mapping?

Answer 36

Stove Burners, Car turn signals

Question 37

An essential principle, probably the most important in communicating a model to the user.

Answer 37

Visibility

Question 38

If the user can’t see an important control, they would have to… ?

Answer 38

guess that it exists and guess where it is.

Question 39

Final principle of interface, this is what the system does when you perform an action. The response of a system, essentially.

Answer 39

Feedback

Question 40

The second set of principles fall under the general umbrella of. . . ?

Answer 40

Consistency

Question 41

Affordances and natural mapping are examples of a general principle of learnability:

Answer 41

Consistency

Question 42

This rule is often given the hifalutin name the Principle of Least Surprise

Answer 42

Consistency

Question 43

Three Kinds of Consistency

Answer 43

• internal consistency within your application;
• external consistency with other applications on the same platform; and
• metaphorical consistency with your interface metaphor or similar real-world objects.

Question 44

One important area of consistency is in _______– where controls and information are displayed on the screen. This is the reason that menu bars appear at the top of the screen (or window).

Answer 44

layout

Question 45

An important kind of consistency that entails using the same terms throughout your user interface

Answer 45

Consistency in Wording

Question 46

This consistency in wording is important too. In other words, speak the user’s language as much as possible.

Answer 46

External consistency in wording. (If the user speaks english, the interface should also speak english, don’t use technical jargon that only you can understand)

Question 47

External Consistency also comes from following. . . ? Many platforms have coded his into a rulebook,

Answer 47

Platform Standards

Question 48

This is one way you can bring the real world into your interface.

Answer 48

Metaphor

Question 49

This person finesses the issue of consistency still further. His argument is that consistency should not be treated as a sacred cow, but rather remain subservient to the needs of context and task.

Answer 49

Jonathan Grudin (in Case against Consistency)

Question 50

Learnable interfaces should clearly communicate. . .?

Answer 50

The correct mental model to the user

Question 51

Learnable Interfaces should?

Answer 51

• Use affordances, natural mapping, visibility
  Consider metaphors.
• Be consistent internally, externally, and metaphorically.
• Prefer knowledge in the world over knowledge in the head.