Download Questions with Model Answers:

Questions with Model Answers:
Question 1: “Usability” is one of the most commonly used terms in User Interface
Design and Human Computer Interaction. Although there is no generally agreed
definition of usability, several suggestions have been made.
A: Show that you understood the meaning of usability by explaining the term in your
own words. (7 marks)
B: Subsequently, name the 9 general interface usability principles that Molich and
Nielsen (1990) consider essential for supporting the usability of graphical user
interfaces (GUI). (9 marks, i.e. 1 mark each for each of the 9 principles)
C: Give a one sentence example for each of the 9 principles. (9 marks)
(25 marks in total)
Model Answer: The International Standards Organization defines Usability as:
“Usability is the degree to which specific users can achieve specific goals within a
particular environment; effectively, efficiently, comfortably, and in an acceptable
manner.” The students’ explanation of usability could be similar to this definition or
rather different by choosing different words. It will be important that the student has
understood the meaning of this term. S/he could also refer to the usability criteria
given by Shackel (1991): effectiveness, learnability, flexibility, and positive user
attitude or to the more general definition that usable systems are considered to be
those which are relatively easy to learn and easy to use.
The second part of the question deals with the general interface usability principles
for GUI identified by Molich and Nielsen (1990):
1. Simple and natural dialogue: dialogues should appear in natural and logical order,
i.e. the dialogue should match with the user’s task organisation. Moreover, dialogues
should be as easy to understand as possible and not contain irrelevant information. An
example could be the help option in Microsoft word, but other examples are possible.
2. Speak the user’s language: the dialogue should be expressed in words, phrases and
concepts that are familiar to the user and should avoid technical jargon. Examples
could relate to online help messages or the graphical icons of printer or rubbish bin on
the desktop, because these icons are familiar concepts to most users. Many other
examples would be possible as well.
3. Minimise the user’s memory load: The user should not have to remember
information from one part of the dialogue to another. An example would be the
graphical interface of a step by step program installation (when users have to press
next after a step is complete and they do not have to remember information).
4. Consistency: The same words should always be used to define the same terms, e.g.
when there is a point in the menu that is called Chart, it should be called like this
consistently and not called Figure elsewhere in the program.
5. Provide feedback: The system should provide appropriate feedback within a
reasonable time to tell the user what is going on, e.g. “Installation was successful.
Please restart your computer”.
6. Provide clearly marked exits: Users often select functions or menu options
erroneously and want a clearly marked exit to go back to where they were earlier. An
example would be the Cancel option that is available in many operating systems.
7. Provide shortcuts: Clever shortcuts – unseen by the novice user – may speed up the
interaction with the system for the expert user. For example, the symbol of a disk
stands for save file, and the same option can be found in the File menu.
8. Good error messages: Error messages should be expressed in a language that users
are able to understand and that constructively suggest a solution, e.g. “The printer ran
out of paper.”
9. Prevent errors: Even better than good error messages is a careful design that
prevents errors from occurring in the first place. An example would be to disable
menu options that make a selection impossible in a given situation.
Question 2:
A: Explain the 3 types of human memory/memory functions. (15 marks, of which 5
marks each are for each type of memory function)
B: Also refer to how information is passed from one type of memory to another (5
marks, of which 2.5 marks are for referring to how information is passed from
type 1 to type 2 and 2.5 marks are for explaining how information is passed from
type 2 to type 3)
C: Why do you think is it important to know about human memory in the context of
user interface design? (5 marks)
(25 marks in total)
Model answer: The 3 different kinds of human memory are Sensory Buffers, Shortterm (=Working) Memory and Long-term Memory.
The Sensory Buffers act as buffers for stimuli received through the senses, e.g. there
is iconic memory for visual stimuli, echoic memory for auditory/aural stimuli and
haptic memory for touch. These sensory memories are constantly overwritten by new
information coming in through these sensory buffers, e.g. information only remains in
iconic memory for about 0.5 seconds.
Passing information from Sensory Buffers to Short-term Memory: Information is
passed from the Sensory Buffers to Short-term Memory by attention, i.e. by filtering
the stimuli so that only the interesting ones are attended to for longer.
Short-term Memory (also called Working Memory) acts as a “scratch-pad” for the
temporary recall of the information. It is the place where information is held
temporarily for another processing activity such as handling inputs, selecting,
retrieving, storing, planning, and preparing outputs. The Short-term Memory’s
capacity to hold information is limited in both amount and time, e.g. on average, the
number of chunks (=digits, names, letters, concepts) people can remember at any one
time is 7 +/- 2.
Passing information from Short-term Memory to Long-term Memory: Information
can be passed from Short-term Memory to Long-term Memory through rehearsal, but
only meaningful information is likely to be remembered.
Long-term Memory stores knowledge of facts, personal memories and skills.
Information is placed into Long-term Memory from Short-term Memory after a
couple of seconds. There are two types of Long-term Memory: episodic and semantic
memory. Episodic memory stores things we have experienced throughout our lives in
serial form, whilst semantic memory is a structured record of facts, concepts and
skills we have acquired.
In the context of user interface design, knowledge about memory is important for a
number of reasons: Because information is passed from the Sensory Buffers to Shortterm Memory through attention, it is important to know how to focus users’ attention
on what they need to be looking at and how to guide their attention to the relevant
information on the display. Because it is also known that only meaningful information
is likely to be remembered in the long run, it is important to design meaningful
interfaces, e.g. easily recognisable icons. Moreover, it is known that people recognise
information more easily than they recall information. This explains why most users
are better able to use graphical user interfaces than command language interfaces
(with graphical user interfaces they click on the icons which they recognise relatively
quickly once they have got to know them, whilst most people find it harder to recall
the commands that are used in command language interfaces).
Question 3:
A: Compare 4 different forms of user support out of the 5 forms presented in the
Lectures. (16 marks, of which 4 marks each are for each form of user support)
B: For 2 out of these 4 forms, also discuss potential problems that people may
experience (you can select your own examples). (6 marks, of which 3 marks each
are for each discussed problem)
C: What solutions would you recommend in each of the 2 cases in order to get round
these problems? (3 marks, where 1.5 marks each are for each of the 2 solutions)
(25 marks in total)
Model answer: There are different types of user support (online help, hypertext and
hypermedia, printed manual, tutorials, expert operated help desks).
Online help messages cannot be lost, do not require desk space because they occur on
the screen and enable to search more effectively by making use of keywords.
Moreover, they can be updated more easily than hard copies. In addition, the user can
adaptively control the level of information s/he would like to get. On the other hand,
paging might be slower and less legible as printed manuals and the user cannot add
marks. Many online help menus are organised hierarchically. As a consequence, users
may face problems navigating through the system. The solution to this problem is to
reduce menu hierarchy to as few levels as possible and show options at the next level
once the user scrolls over the respective item in the menu.
Hypertext and Hypermedia: Hypertext consists of a collection of non-linear, textbased nodes that are linked together. When adding various media such as animations,
video, sound to Hypertext, this is typically called Hypermedia. The advantage of
Hypermedia is that help provided through this type of user support might be
understood better because sequences of actions can be shown as video animations. A
disadvantage would be that too much animation might confuse the user. A solution to
avoid confusing the user would be to provide good tools of navigation and to allow
users to develop adequate mental models of the system for which help is sought.
Navigational abilities can be enhanced if the designer lets the user adopt a “printed
magazine” metaphor with a reference section and an exploratory section that lets the
user browse the contents.
Printed Manuals: Printed manuals might allow faster paging than online help, and
they might be better legible as well. They also allow the user to make marks.
However, they can be lost, do require desk space and cannot be updated without
replacing the hard copy. The most significant problem, though, is that user manuals
are poorly designed, because they often involve a lot of technical jargon and are
therefore difficult to read. Moreover, writing manuals is often left to the most
inexperienced people (e.g. summer interns). A solution would be to prepare the
writing of a manual really well and to avoid technical jargon, to be consistent with the
terminology, style, layout etc. across all chapters of the manual.
Tutorials: Here learners are expected to go through the entire manual from the
beginning to the end. This might include teaching and practical sessions. Practical
sessions are typically very useful, because they foster direct interaction with the
system. A problem occurs if a person gets lost within the learning process. A solution
might be to design tutorials in order of increasing difficulty and to make sure that
each participant has mastered the sub-learning processes until the next learning
process starts.
Expert operated help desks: It is important that experts have excellent training and
communication skills, i.e. they must understand what sort of problems users are likely
to experience and they must be able to explain technical problems in a clear way. The
problem is that in reality, this does not always work as well as it should be. The
solution would be to enable the experts specific training before they operate on a help
desk and to let them run many practical session with novice users of the system.
Question 4:
A: Explain what is meant by user-centred design by referring to user-centred design in
general. (9 marks)
B: Also explain the 4 principles that were identified by Gould et al. (1987). (12
marks, of which 3 marks each are for explaining each of the 4 principles)
C: Give a sensible example for each of the 4 principles. (4 marks, of which 1 mark
each is for each example)
(25 marks in total)
Model answer: User-centred design is a design of the interaction from the view of the
user rather than the view of the system. Its aim is to produce systems that are easy to
learn and use, safe, as well as effective by facilitating the actions people want to
perform. It should be focussed on what is best for the user, instead of what is easiest
to implement. For this purpose, the most important factor is to get to know the user,
which can be achieved by different techniques such as questionnaires, interviews,
observation of user interaction with the system, etc.
User-centred design is a rapid and iterative design process with repeated evaluations.
It focuses on users, their work, environment, and how technology can support them in
the best possible way.
The principles that were identified by Gould et al (1987) are:
1. To focus on users and their tasks early on in the design process. This includes user
guides, help and ensuring that users’ cognitive, social, and attitudinal characteristics
are understood and accommodated.
2. To use prototype manuals, interfaces, and other simulations of the system in order
to measure how the user interacts with possible future systems.
3. To design iteratively because designers, no matter how good they are, cannot get it
right the first few times.
4. All usability factors must evolve together and be under the responsibility of one
group that supervises the whole design process.
The examples just have to make sense. There is no requirement in terms of what
example the student should select.
Question 5: Prototyping is a very popular method in User Interface Design.
A: Give 4 reasons to support the argument that the repeated use of prototyping until
the end of the design process is useful in user interface design (give 4 sensible
reasons). (10 marks (2.5 each) are for the 4 reasons)
B: Briefly also describe the 5 aspects from the lectures where Prototyping helps
designers to make decisions. (10 marks (2 each) are for the 5 aspects)
C: Choose one sensible example for each of the 5 aspects. (5 marks, i.e. 1 mark is
for each example)
(25 marks in total)
Model Answer: Below are several reasons. The students only need to refer to 4
sensible reasons, of which the following reasons are just examples. In User Interface
Design, the notion has been made that no matter how good designers are, they never
get it right in the first place. Moreover, user interface design is often aimed at novel
interfaces that people have not experienced before. This implies that the user interface
often needs a lot of refinement, based on the comments of its users. It would be time
consuming and often too expensive to design a complete interface, test it, design an
alternative interface, test the alternative interface and so on. Rather, prototyping
allows to create models of the system quickly and efficiently. These prototype models
can be tested by their users. Subsequently, the models can be refined according to the
user’s suggestions, tested again and so on. Because the prototype is less expensive
and can be built more rapidly, a lot more refinement can be made in the same time by
using this method, i.e. efficiency is a main criterion.
The 5 aspects from the Lecture where Prototyping helps designers to make decisions
on:
1. the functionality of the system
2. operation sequences
3. user support needs
4. required representations
5. look and feel of the interface
The examples to these 5 aspects can be chosen arbitrarily. They just need to be
sensible examples.
Question 6: There are people who argue that good preparation and organisation
before designing the user interface can replace its evaluation.
A: Provide 5 sensible reasons against this argument. (15 marks, of which 3 marks
each are for each of the 5 reasons)
B: Briefly explain the 2 main kinds of evaluation in interaction design that were
mentioned in the Lecture/Study Guide. (8 marks, of which 4 marks each are for
explaining the 2 main kinds of evaluation)
C: Also state which of the 2 main kinds of evaluation is more common for usability
testing. (2 marks for stating the correct one)
(25 marks in total)
Model answer: Many systems have been developed that are considered functionally
excellent, but perform badly in the real world. For this reason, it is generally
considered that there is no way around evaluation. Otherwise, it would be hard to
figure out whether the users’ needs are really accomplished by the user interface.
What follow are 5 possible reasons, but it will be accepted if the students name
sensible reasons other than the ones below:
1st reason: without evaluation the possibility could not be excluded that designers do
not properly understand the user.
2nd reason: that computer systems are intolerant of minor errors.
3rd reason: that the systems cause unacceptable changes in the practices of
organisations, creating dissatisfaction and conflict etc.
4th and 5th reason: It is generally recommended to start evaluation at the beginning of
the design process, and it is often considered a good idea to make use of prototypes
that can be continuously changed and evaluated. Reasons for evaluation could be to
find out how the design can be improved to fit the users’ needs better, or to compare
different designs with each other. These goals would definitely be hard to achieve
without any form of evaluation.
Formative Evaluation: Evaluation of the interaction design as it is being developed,
early and continually throughout the interface development process. Formative
evaluation is often used several times throughout the process of evaluating a user
interface design.
Summative Evaluation: Evaluation of the interaction design once it is complete or
nearly complete. Summative evaluation is often used to compare one product with
another.
Formative Evaluation is more common for usability testing.