The document discusses the importance of ergonomics and usability in the design of web pages and applications, highlighting the evolution and development of artifacts as tools that not only meet needs but also create and change them. It emphasizes the idea that no artifact is perfect, and all can improve over time, particularly in the context of complex tasks. Additionally, it touches on concepts like survivorship bias and co-evolution between tools and users, using historical examples to illustrate these points.

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ERGONOMICS APPLIED TO THE DESIGN OF USABLE WEB
PAGES AND APPS
Roberto DADDA and Paolo NEGRI

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Artefacts
Considerations on man made tool
development
Needs/artifacts cycle

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Man is a Tool-Making Animal

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How artifacts are developed?
www.museum.ie
ksiezycowahipoteza.wordpress.com

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The static vision
Form follows function
task artefact

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Every artefact, also the simplest, exists in several versions

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The dynamic vision
Form follows failure
task artifact
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Humble telescope

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Corollaries
• The perfect artefact does not exist
• Everything can be made better… and will be
•
• Every artifact will exist in several versions…
• … specially when in used to support complex
tasks ...as in WEB pages and interfaces
https://it.wikipedia.org/wiki/Panta_rei
(1)

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Example: paper clips
1896

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Not always good form comes immediately

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And the winner is…

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1

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roberto dadda
1

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task
artefacts
Tools does non only satisfy needs,
tools changes and creates them!

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Mimeograph

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Xerox, 1949
IBM 3800 in 1976
Apple laserwriter 1985
1959

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Failure identification: not always easy
Abraham Wald 1902-1950
De Havilland Mosquito (UK)

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Wald’s insight and reasoning was based
on understanding what we now call
survivorship bias. Bias is any factor in
the research process which skews the
results. Survivorship bias describes the
error of looking only at subjects who’ve
reached a certain point without
considering the (often invisible) subjects
who haven’t.

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Computer, Eniac & CRC102A

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roberto dadda
“As tools are introduced and
used, a co-evolution will occur
between the tools and the
people using them”
D.C.Engelbart
2

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Usability
Roberto DADDA
roberto@dadda.it
www.dadda.it
Skype, Facebook e Twitter robertodadda