5. Module aims
• To provide students with the core theoretical background
necessary for the implementation of usable software interfaces
• To introduce the student to techniques for the assessment of
software interface
• To provide a practical experience of implementing usable
software interfaces
• To provide a practical experience of assessing the usability of
software interfaces
• To form basis for the application of Usability Engineering in
industrial practice
• To encourage the development of successful problem solving
strategies and to contribute to the development of academic skills
throughout their programme of study
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6. Learning outcomes
• LO1: Apply the knowledge of user needs to an
Information System application specification
• LO2: Apply appropriate design and specification
standards
• LO3: Have an awareness of current practices in the
development of systems for people
• LO4: Effectively evaluate various systems and make
appropriate design decisions
• LO5: Prepare and present design specifications
• LO6: Manage own time
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7. Module structure (tentative)
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
Usability: introduction
Accessibility: introduction
SPEL (Social, political, ethical and legal) issues
Usability evaluations (part 1)
Usability evaluations (part 2)
UCSD
Introduction to task analysis
Requirements gathering
Cognitive psychology for usability
Guidelines and standards for design.
UCSD and advanced technologies
Don’t make me think
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9. Usability in context
• Usability is a wide research field that
involves researchers from different
disciplines such as:
– Communication Science, Psychology and
Sociology
– Computer Science and Engineering
– Human Computer Interaction and
Ergonomics.
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10. Usability definitions: IEEE 90
• "The ease with which an user can learn to
operate, prepare inputs for, and
interpret outputs of a system or
component." (IEEE 90).
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11. Usability definitions: ISO 9241
• "The extent to which a product can be
used by specified users to achieve
specified goals with effectiveness,
efficiency and satisfaction in a specified
context of use." (ISO 9241).
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12. Usability definitions: ISO 13407
• "The usability of an interface is a measure
of the effectiveness, efficiency and
satisfaction with which specified users
can achieve specified goals in a
particular environment with that
interface." (ISO 13407).
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13. Usability definitions: summary
• The first definition stresses the "easy of use" of a system
and the actions that should be easily performed
(operating with a system, preparing input, interpreting
output).
• The second definition states that usability is not a
generic concept, but that it is specific to individual users
and contexts. It also clarifies that the goals for which a
product is used have to be achieved with effectiveness,
efficiency and satisfaction.
• The third definition is very similar to the second, but
stresses that usability is a measure of a condition, not a
static property of an artefact.
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15. Interface
• A interface is the means by which
interaction is achieved
– E.g. The keyboard is one of the possible
interfaces for a PC
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16. Effectiveness
• Effectiveness: each user has a particular
goal to achieve when using an interface.
• Effectiveness measures if the expected
goals have been achieved and measures
the accuracy and completeness of the
specified goals.
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17. Efficiency
• Efficiency: measures the effort necessary
to achieve the user’s goal and if it is
proportionate to the expected result.
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18. Satisfaction
• Satisfaction: measures the pleasantness
of using a particular interface and if the
interface is suitable or not for the desired
goal.
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19. Usability roots
• While it can be difficult to find the "first" usability study
we can find interests in usability that can be dated at
least to classic authors.
• Greek and Roman authors were already aware of the
problems related to Ergonomics, but we cannot find a
systematic exposition of the issues.
• The environment and its relation to worker health were
recognized as early as the fourth century BC when
Hippocrates noticed lead toxicity in the mining industry
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20. Usability Roots: Bernardo
Ramazzini
• “The maladies that affect the clerks arise
from three causes: first, constant sitting;
secondly, incessant movement of the hand
and always in the same direction; and
thirdly, the strain on the mind.”
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21. Usability Engineering
• Usability Engineering is the discipline that
focuses on implementing and assessing
the usability of an interface.
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24. Tutorial groups
• You should all have been allocated a
Tutorial/Practical group, but if you have not
been allocated a group yet:
– If you are a part-time student or a Combined
Honours student, please attend to Group 1
– Otherwise, please attend to Group 2
25. IM2044 is a green module
• You will not receive a printed copy of your
handbook
• You will not receive printed notes/slides
• You will not have to hand in any printed work
and you will have a on-line submission
– Submission at the helpdesk will NOT be available
– You will receive on-line feedback for you assessment
26. Readings and resources for the
module
• The core text book for this module is
– Sharp, H., Rogers, Y. and Preece, Y. (2007)
Interaction Design: Beyond Human-Computer
Interaction, 2nd edition, John Wiley & Sons.
• A list of recommended readings is
included in the Module specifications at
the end of your Module Handbook
27. UELPlus
• Slides, teaching material, module
handbook are ALL in UELPlus
– The teaching material in the UELPlus pages
might be updated during the semester
– Keep an eye for updated documentation
• The assignment will be released in week 3
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