2. Evaluation
• Well, before addressing the evaluation of
paper prototypes, perhaps we should consider
reasoning upon what we should
evaluate, right?
– Let’s then take a look into concepts such as
usefulness, usability and user experience
3. Usefulness
• Usefulness is a crucial quality of any product
or service
– Concerns the degree to which a product enables a
user to achieve his or her goals, and is an
assessment of the user’s willingness to use the
product or service at all
• Without usefulness, other measures make little or no
sense, because it will just sit on the shelf
• We name this the fundamental quality of a
product or service
4. Usability
• According to the ISO standard
– Usability is the extent to which a product or
service can be used by specific users to achieve
predefined goals in a specified context of use
– The standard defines three main usability
dimensions:
• Effectiveness,
• Efficiency, and
• Satisfaction
5. Usability
• Anyway, when looking into usability, we
normally account for:
– Effectiveness
– Efficiency
– Satisfaction
– Learnability
– Memorability
• We name these the pragmatic qualities of a
product or service
6. Usability
• Common reason for the delivery of less usable
products are
– System focused process
– Poorly integrated teams
– Design and development mismatches
– And of course, designing usable products is
difficult
• That’s what we are pushing paper prototyping in this
moment of the process
7. User Experience
• According to its ISO standard, user experience
is a person’s perception and responses that
result from the use or anticipated use of a
product or service
8. User Experience
• User experience subsumes usability and
includes includes
– emotions, beliefs, preferences, perceptions, physic
al and psychological responses, behaviors and
accomplishments that occur before, during and
after use
• We name these the effected of the
hedonic, or pleasure related, qualities of a
product or service
9. Evaluation
• As stating in the beginning, before addressing
the evaluation of paper prototypes, we should
consider reasoning upon what we should
evaluate
– And now that we briefly cover
usefulness, usability and user experience, I believe
it’s fair to say that we should target going as far as
usability
10. Evaluation
• In general, product and service evaluation can
be formative or summative
• Paper prototype evaluation is mostly
formative
11. Evaluation
• Paper prototype evaluation focus on…
– The most significant issues preventing users from
accomplishing their goals
– What works and what do users find frustrating
– What are the most common errors or mistakes
users are making
– Assessing the improvements being made from one
design interaction to the next
– Identifying issues that are expected to remain
even when the product is launched
12. Evaluation
• Today we look into
– Inspection methods
• These are methods where an expert evaluator inspects
a product or service
– Testing methods
• These are methods where products and services are
evaluated by testing them on real users
13. Inspection methods
• There are also several but we will address:
– Cognitive walk-through
– Heuristic evaluation
14. Cognitive walk-through
• The purpose is to verify if the paper prototype
actually allows the fulfillment of the selected
user stories
– This is a within team activity that ensures that
your prototype complies with the identified user
stories
15. Cognitive walk-through
• Designers and developers of the product or
service then walk through the steps as a
group, asking themselves a set of questions at
each step
– Data is gathered during the walk-through, and
afterwards a report of potential issues is compiled
– Finally the evaluated proposition is redesigned to
address the issues identified
16. Heuristic evaluation
• This is a type of evaluation ideally carried out
by an expert.
– It specifically involves evaluators examining the
design and judging its compliance with recognized
principles, such as Jakob Nielsen’s 10 usability
heuristics
• These evaluation methods are now widely taught and
practiced in the new media sector, where products and
services are often designed in a short space of time on
a budget that may restrict the amount of money
available to provide for other types of interface testing
18. Co-discovery
• Two users attempt to perform tasks together
while being observed
– They are to help each other in the same manner
as they would if they were working together to
accomplish a common goal using the product
– They are encouraged to explain what they are
thinking about while working on the tasks
19. Co-discovery
• The designers and developers should refrain
from explaining the design decisions and
rather focus on getting the most of the pair of
users tacking with your prototype
– Note taking is fundamental and you should run
this kind of test until no significant additional
information is feed back into the design process
20. Wizard of OZ
• This is a testing approach built upon a paper
device instead of using a working technological
artifact
– This king of testing involves systematic observation
under controlled conditions to determine how well
people can use a product or service
– Rather than showing users a rough draft and asking,
Do you understand this?, this kind of testing involves
watching people trying to use something for its
intended purpose
21. Wizard of OZ
• Setting up such a test involves asking the test
subjects to recreate a set of user stories after
being introduced to the underlying scenario
– For example, to test the attachment function of an
e-mail program, a scenario would describe a
situation where a person needs to send an e-mail
attachment, and ask him or her to undertake this
task
– The aim is to observe how people function in a
realistic manner, so that developers can see
problem areas, and what people like.
22. Testing methods
• This kind of evaluation should be repeated
until no significant added value comes from
bring in an additional subject
– The usual number is 5, but other claim otherwise
23. Pre and post-tests
• When applying testing methods, pre-test and
post-test questionnaires are also used to
gather feedback on the product being tested
– A common questionnaire is the 25 years old
System Usability Scale
25. Evaluation protocol
• But these methods are useless without an
adequate evaluation protocol
• While designing your evaluation protocol, you
should take into account…
– A mixed selection of inspection and testing
methods;
– The user stories supported by your prototype; and
– The affordances of your paper prototype.
26. Evaluation protocol
• Examples are provided in the companion blog
but please note that…
– In all cases, evaluation protocols should be piloted
to ensure that once they are being applied, you
are actually focusing in assessing the prototype
and not on solving evaluation protocol issues