The document discusses the principles of ergonomics and usability in web and app design, emphasizing quality as a subjective attribute tied to user expectations. It defines usability as the effectiveness, efficiency, and satisfaction of a product in achieving user goals within a specific context. Key aspects of usability highlighted include learnability, efficiency, memorability, error management, and user satisfaction.

1. www.dadda.it roberto@dadda.it Excellence in usability 1st semester 2021-2022 1
ERGONOMICS APPLIED TO THE DESIGN OF USABLE WEB
PAGES AND APPS
Roberto DADDA and Paolo NEGRI

2. www.dadda.it roberto@dadda.it Excellence in usability 1st semester 2021-2022 2
Quality, Ergonomics
&Usability
Our main goal!

3. www.dadda.it roberto@dadda.it Excellence in usability 1st semester 2021-2022 3
Quality
• In business, engineering, and
manufacturing, quality has a
pragmatic interpretation as the
non-inferiority or superiority of
something; it's also defined as
being suitable for its intended
purpose (fitness for purpose)
while satisfying customer
expectations. Quality is a
perceptual, conditional, and
somewhat subjective attribute
and may be understood
differently by different people.
Wikipedia

4. www.dadda.it roberto@dadda.it Excellence in usability 1st semester 2021-2022 4
Ergonomics
• Human factors and
ergonomics (commonly referred to
as human factors) is the application
of psychological and physiological
principles to the (engineering and)
design of products, processes, and
systems. The goal of human factors
is to reduce human error, increase
productivity, and enhance safety
and comfort with a specific focus
on the interaction between the
human and the thing of interest.
wikipedia
Leonardo da Vinci, Vitruvian man

5. www.dadda.it roberto@dadda.it Excellence in usability 1st semester 2021-2022 5
SFCO 1906

6. www.dadda.it roberto@dadda.it Excellence in usability 1st semester 2021-2022 6

7. www.dadda.it roberto@dadda.it Excellence in usability 1st semester 2021-2022 7
Definition
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)
ἴσος (equal)

8. www.dadda.it roberto@dadda.it Excellence in usability 1st semester 2021-2022 8

9. www.dadda.it roberto@dadda.it Excellence in usability 1st semester 2021-2022 9
Learnability
• How easy is for the users to accomplish basic tasks the first time they
encounter the design?

10. www.dadda.it roberto@dadda.it Excellence in usability 1st semester 2021-2022 10
Efficency
• Once the users have learned the design how quickly can they perform
the tasts?

11. www.dadda.it roberto@dadda.it Excellence in usability 1st semester 2021-2022 11
Memorability
• When users return to the design after a period of not using it how
easily can they re estabilish proficency?

12. www.dadda.it roberto@dadda.it Excellence in usability 1st semester 2021-2022 12
Errors
• How many errors the user makes, how severe are these errors and
how easily can they recover from errors?

13. www.dadda.it roberto@dadda.it Excellence in usability 1st semester 2021-2022 13
Satisfaction
• How pleasant is it to use the design?

14. www.dadda.it roberto@dadda.it Excellence in usability 1st semester 2021-2022 14

15. www.dadda.it roberto@dadda.it Excellence in usability 1st semester 2021-2022 15
User experience

16. www.dadda.it roberto@dadda.it Excellence in usability 1st semester 2021-2022 16
Usability

17. www.dadda.it roberto@dadda.it Excellence in usability 1st semester 2021-2022 17
Usability: key factor of success

18. www.dadda.it roberto@dadda.it Excellence in usability 1st semester 2021-2022 18
Necessary but not sufficient

19. www.dadda.it roberto@dadda.it Excellence in usability 1st semester 2021-2022 19
Usability
Roberto DADDA
roberto@dadda.it
www.dadda.it
Skype, Facebook e Twitter robertodadda