long - ppt - UTRGV Faculty Web

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Transcript long - ppt - UTRGV Faculty Web

Web Site Design
Web Site Design
• HCI and the Web –
– Knowledge of interface design, applied to web
– Won’t consider tools, programming – other classes, e.g., internet programming
• Web is a different sort of system … than “stand alone” sys
– Not just an “interface”, though principles (and techniques) apply
• Site Design
– Structure and information architecture
• Page design
– Page scanning and canonical form
– Visual logic and hierarchy
Web is Different, but …
1. Software system design principles are same
– Much of web design literature “comes in at the bottom”
• I.e., for novice (untrained) designers
• Though may apply principles, do not provide broader disciplinary context
– Student of computer science understands ideas about software engineering and
principles of design
• E.g., Lynch and Horton “team roles” and SE project members
2. Interface design principles, are same for “web-based” (or
browser-based) systems and “stand-alone” systems
– E.g., Shneiderman’s 8 “Golden Rules”, Nielsen and Toggazinni’s principles
3. Web is not “hypertext” (yet), yet many lessons of even pre-web
hypertext are relevant
– E.g., “lost in hyperspace”, pre-WWW study, cf. SIGWEB
About Web Design – In Practice
•
Goal of hypertext:
–
–
•
And, yes, WWW is hypertext, at least in limited sense
–
–
–
•
But, technology (of network access) is really young, and slow:
bandwidth limitations drive much of “practical/applied” web site design
And, yes, television held great promise, too, …, but that’s another story
Note that much of what users see in Web sites (and even
“good” web sites) is driven by economic factors, rather than
“user-centered” design
–
–
•
“an electronic medium in which information presentation and access mirrors
human cognition and thus can be more efficient and effective as a medium for
communication (than printing)”
Also, admittedly early on in development of use and evolution of techniques
i.e., design in which user’s (vs. the business’) best interests are design goal
Often/typically real goal of site is to sell advertising
•
Business models for Internets are evolving – and Google’s is atypical …
Nonetheless, our focus is on user-centered design
–
Design in which user can access information efficiently and effectively, etc.
1. Software Design Principles are Same
• Project stages of L&H reflect, different emphases, but same stages
1. Software Design Principles are Same
… note terminology differences
• Project roles of L&H reflect, different emphases, but same roles
•
•
Project stakeholder or sponsor
Web project manager
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–
•
•
•
•
–
–
–
–
•
•
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Site copywriter
Content domain expert (content coord., res.)
Web application programmer
Web page engineer (xhtml, css)
Database administrator
Web systems expert or webmaster
(under “Lead Prog”) Site production lead
–
•
Web graphic designer
Interactive designer (Flash, …)
Media specialist (photography, illustration)
Lead Programmer/Architect
–
–
–
–
html page coder
Site editor
–
–
•
Account executive
Quality assurance tester
Usability lead
(e.g., database under “Lead Prog”/”arch”)
(e.g., Art director under “Lead…
)
–
–
–
Web application programmer
Web page engineer (xhtml, css)
Database administrator
Web systems expert or webmaster
Site production lead
–
•
•
•
Web graphic designer
Interactive designer (Flash, JavaScript, Ajax)
Media specialist (photography, illustration)
Web technology lead
“Client” - Boss
Project manager
–
–
Account executive
Quality assurance tester
Usability lead
Information architect –site content and structure
Art director
–
–
–
•
•
html page coder
(with database, under “Lead …) Site ed.
–
–
Site copywriter
Content domain expert (content , res.)
1. Software Design Principles are Same
• … or similar
1. Software Design
Principles are Same
• … or similar
• Here, provide detail
specific to web sites
2. Interface Design Principles are Same
• Have had a close look at:
– Guidelines, principles, and theories
Guidelines, Principles, and Theories
• Guidelines (most specific)
–
Specific and practical
•
–
–
–
Cure for design problems, caution dangers,
shared language and terminology
Accumulates (and encapsulates) past
experience and best practices
•
“blinking is bad, never use it”
–
“Rules that distill out the principles of
effective user interfaces”
–
More general and flexible than guideline
•
E.g., Determine users’ skill level
• High level theories and models
Goal is to describe objects and actions with
consistent terminology
•
–
Principles
May be: too specific, incomplete, hard to
apply, and sometimes wrong
Lowest level
• Principles (“rules of thumb”)
–
Theories
Allowing comprehensible explanations to
support communication and teaching
Other theories are predictive
•
E.g., reading, pointing, and typing times
Guidelines
… and recall, Principles: Shneiderman’s
“8 Golden Rules of Interface Design”
•
Schneiderman’s 8 rules (principles):
1.
2.
3.
4.
5.
6.
7.
8.
Strive for consistency
Cater to universal usability
Offer informative feedback
Design dialogs to yield closure
Prevent errors
Permit easy reversal of actions
Support internal locus of control
Reduce short term memory
… as well as Nielsen’s
Principles for Usable Design
• Meet expectations
– 1. Match the real world
– 2. Consistency & standards
– 3. Help & documentation
• User is the boss
– 4. User control & freedom
– 5. Visibility of system status
– 6. Flexibility & efficiency
• Handle errors
– 7. Error prevention
– 8. Recognition, not recall
– 9. Error reporting, diagnosis, and recovery
• Keep it simple
– 10. Aesthetic & minimalist design
… even Toggazinni’s 16 Principles
• Anticipation
• Human interface objects
• Autonomy
• Latency reduction
• Color blindness
• Learnability
• Consistency
• Metaphors
• Defaults
• Protect users’ work
• Efficiency
• Readability
• Explorable interfaces
• Track state
• Fitts’s Law
• Visible navigation
Web Site Design
differs from User Interface Design
•
WWW not same kind of interactive system, as “computer interface”
•
–
–
•
(at least as discussed in traditional HCI literature)
Looong latency
•
1/10 – 1/30 second required for perceptual continuity
•
1 sec continuity of interaction
– i.e., “immediate response”
•
~ 10 (or 5-30) seconds for task continuity
So, response time from web is at limit of task continuity
Different, and not an interactive system with “immediate” response
–
–
•
not to be studied in same way many elements of interfaces are
and maybe principle focus and principles of design yet to evolve
Thus www, acts as information repository, and other things
–
–
Whether for “knowledge”, shopping, chatting, ..., but not traditional system
Hence, focus on information architecture
Difference Between Web Design and
GUI Design – Nielsen
• Designing for Web different from designing traditional user interfaces
– Designer has to give up full control
• Share responsibility for the UI with users and their client hardware/software.
• Device Diversity
– In traditional GUI design, control every pixel on the screen
• Designing to abstract UI specification is hard
– Those these days with javascript, etc. much more freedom
• The User Controls Navigation
– Can jump straight into the middle of a site from a search engine!
• On Web, users move between sites at a very rapid pace and the
borders between different designs (i.e., sites) are very fluid
The Difference Between Web Design
and GUI Design – Nielsen, 1
• Designing for Web different from for traditional user interfaces
– Designer has to give up full control
• Share responsibility for the UI with users and their client hardware/software
• Device Diversity
– In traditional GUI design, control every pixel on the screen
– In traditional design, the difference in screen area between a laptop and a highend workstation is a factor of six
• On Web, need to accommodate a factor of 100 in screen area between
handhelds and workstations
• A factor of 1,000 in bandwidth between modems and fast connections.
• Designing to abstract UI specification is hard
– Basic principles, e.g., HTML, can take the designer a long way toward the ideal,
but not all the way there.
– Separate meaning and presentation and to use style sheets to specify
presentation
• but doing so works better for informational content than for interactions.
The Difference Between Web Design
and GUI Design – Nielsen, 2
• The User Controls Navigation
– In traditional GUI design, the designer can control where the user can go when
• You can gray out menu options that are not applicable in the current state,
etc.
– On Web, user controls his or her navigation through pages
– Users can take paths that were never intended by designer:
• Jump straight into the middle of a site from a search engine without ever
going through the home page
• Users also control own bookmark menu and can use it to create a
customized interface to a site
• Web designers need to accommodate and support usercontrolled navigation
– Design for freedom of movement and,
• E.g., logo (linked to home page) on every page for context and navigation
for users who have gone straight to that page.
The Difference Between Web Design
and GUI Design – Nielsen, 3
• “Part of a Whole”
– A traditional application is an enclosed user interface experience:
• User is fundamentally "in" a single application at any given time and only
that application's commands and interaction conventions are active.
• Users spend relatively long periods of time in each application and become
familiar with its features and design.
• On Web, users move between sites at a very rapid pace and
borders between different designs (i.e., sites) are very fluid
– Often users spend less than a few minutes at a time at any given site,
• Users' navigation frequently takes them from site to site to site as they follow
hyperlinks.
– Because of this rapid movement, users feel that they are using the Web as a
whole
• … rather than any specific site:
– Users demand ability to use site on basis of Web conventions they
have picked up as an aggregate of their experience using other sites.
– In usability studies, users complain whenever they are exposed to sites with too
diverging ways of doing things
• Web as a whole has become a genre and each site is interpreted relative
to the rules of the genre.
3. Web is Different from (Visionary) Hypertext
with respect to types of links/associations
• Bottom line, hypertext and Web can both be modeled as G (V,E)
– For hypertext, edges are undirected and labeled (with anything!)
– For web, edges are directed and unlabeled
• Though, who would know edges undirected (browser makes transparent)
• Web 2.0 and higher aim to provide (semantic) labels
– Promise of the future?
• So, current realization of “world wide repository of knowledge” is
really quite primitive
– But, it is still revolutionary in sheer quantity of information stored,
indexed (sort of), and retrievable
– And, we are early on in implementation
• 2014 – 1991 = 23
– And, all appreciate what next steps need to
• Moore’s law is on our side (though that’s just for computers)
About Web Design
As Presented by L&H and Nielsen
• Recall, hypertext
– Goal of hypertext:
• “an electronic medium in which information presentation and access mirrors human
cognition and thus can be more efficient and effective as a medium for communication (than
printing)”
• also, admittedly early on in development of use and evolution of techniques
– And, yes, WWW is hypertext, at least in limited sense
• But, technology (of network access) is really young, and slow:
– bandwidth limitations drive much of “practical/applied” web site design
• And, yes, television held great promise, too, …, but that’s another story
• Note, that much of what users see in Web sites (and even “good” web
sites) is driven by economic factors - advertising, rather than “usercentered” design
– i.e., design in which user’s (vs. the business’) best interests are design goal
– often, real goal of site is to sell advertising
• Nonetheless, our focus is on user-centered design
– Design in which user can access information efficiently and effectively, etc.
– Perhaps, not a bad place to start in general
• entirely appropriate for many sites
About Nielsen and Style Guide
• Yale Style Manual sometimes seem “quaint”
– “quaint” because of their focus on technology in a domain in
which two years sees significant change in technology
• Again, we’re just (historically) getting started
– HTML 2.0, 3.0, 4.0, 5.0, 6.0, …. Javascript, …, ASP, …, XML,
XHTML, …,
– and Java programs to run in the browser window
• Which really opens things up!
Site: Design – Issues and Tasks, 1
(Overview of L&H 3)
• Or, from a “computer science software engineering” perspective,
– What should the design document (specifications) include
• Preliminary Design Decisions
– Purpose of site
– Objectives
– Audience
• Surfers, novice/occasional users, expert/frequent users, international users
• Design strategies are different for
– Surfers, Training, Teaching, Education, Reference
• Interface Design
–
–
–
–
Web pages versus conventional document design
Design precedents in print
Make Web pages free-standing
Who, What, When, Where
• Interface design issues for Web
– User-centered design (of course), Clear navigation aids, Provide context
Site: Design – Issues and Tasks, 2
(Overview of L&H 3)
• Information Access issues
– Give users direct access
– Consider bandwidth and interaction
– Simplicity, Consistency, Design stability, Feedback and dialog, Design for the
disabled
• Links & navigation
– Provide context, Button bars help
• Site Design
– Organizing information
• Chunking information: Hierarchy, Relationships, Function
– Site structure
• Sequence, Grid, Hierarchy, Web
– Site elements
• Home pages, Graphic or text menus, Audience for home page, "Related
sites", Bibliographies, indexes, appendices, FAQ’s, etc.
About Information Architecture
Web Site Design
differs from User Interface Design
•
WWW not same kind of interactive system, as “computer interface”
•
–
–
•
(at least as discussed in traditional HCI literature)
Looong latency
•
1/10 – 1/30 second required for perceptual continuity
•
1 sec continuity of interaction
– i.e., “immediate response”
•
~ 10 (or 5-30) seconds for task continuity
So, response time from web is at limit of task continuity
Different, and not an interactive system with “immediate” response
–
–
•
not to be studied in same way many elements of interfaces are
and maybe principle focus and principles of design yet to evolve
Thus www, acts as information repository, and other things
–
–
Whether for “knowledge”, shopping, chatting, ..., but not traditional system
Hence, focus on information architecture
About Information Architecture
• About “architecture”:
– Architecture is about design …
• 1. the profession of designing buildings, open areas, communities, and other
artificial constructions and environments
– For computer organization (computer architecture)
– About compromises, experience, …, and design principles
• Information structuring on WWW is almost exclusively about web
site design
–
–
–
–
–
Thus, is changing rapidly due to:
Change in hardware and software technologies:
HTML and variants expanding functionalities, also on server side, asp, …
Uses for web – information dissemination, e-commerce, pure advertising, …
Users – literacy, expertness, expectations, populations, …
About Information Architecture
• “Information architecture”
– Can, in fact, be considered quite generally
• Of “labeled link hypertext”, a library, email folders, …
• Term “information architecture” used for web sites because they are
today (again) primarily information repositories
– With (again) quite primitive information access mechanisms
• Lynch and Horton:
– “In the context of web site design, information architecture describes the
overall conceptual models and general designs used to plan, structure,
and assemble a site. Every web site has an information architecture, but
information architecture techniques are particularly important to large,
complex web sites …”
– This is what they mean on Monster.com
About Information Architecture
some “definitions”
• R. S. Wurman in Information Architects, 1996:
– the individual who organizes the patterns inherent in data, making the complex
clear
– a person who creates the structure or map of information which allows others to
find their personal paths to knowledge
– the emerging 21st century professional occupation addressing the needs of the
age focused upon clarity; human understanding and the science of the
organization of information
•
Louis Rosenfeld, “Making the Case for Information Architecture” at
ASIS 2000 IA Summit:
– “Information architecture involves the design of organization, labeling, navigation,
and searching systems to help people find and manage information more
successfully.”
About Information Architecture
some “definitions”
• … and from Monster.com
– Sacha Cohen, “Becoming an Information Architect: Work as a Web Site
Strategist”
– in monster.com, http://technology.monster.com/articles/infoarchitect/
• Monster.com: First, what exactly is information architecture?
– Mattie Langenberg: Information architecture, as the name implies, is
basically about taking content and creating a structure to present that
content to an audience. Whether the content is intended for a private
audience on an intranet or for the public, it is the information architect's
job to ensure that information is well-organized and presented in an
easily accessible interface.
Information Architecture
• Aims of information architecture (L&H):
– Organize site content into taxonomies and hierarchies of information
– Communicate conceptual overviews and overall site organization to
design team and clients
– Research and design core site navigation concepts
– Set standards and specifications for
• Handling of html semantic markup
• Format and handling of text content
– Design and implement search optimization standards and strategies
• Encompasses a broad range of design and planning disciplines
• In fact, to create cohesive, coherent user experience – combine:
– Technical design
– User interface
– Graphic design
Orientation to Web Site Design, 2
• Web page and site design
– Web page and site design combines (and this is not a short list):
1. traditional editorial approaches to documents
2. graphic design
3. user interface design
4. information design
5.“programming” skills optimize HTML code, graphics, & text within Web pages
• There is a challenge in adapting a relatively primitive authoring and
layout tool (HTML) to purposes it was never really intended to serve
(graphic page design).
• Web serves as an information system and is relatively new
– It can usefully be considered a new medium for which design is evolving
• Will see other differences as well (Nielsen)
How to Organize Information (L&H)
Principles and Guidelines!
•
Inventory site content
– What is available, what is needed
•
Establish a hierarchical outline of content
– Will likely serve as site structure!
•
Create a controlled vocabulary
– Allows consistent identification of content, site structure, and navigation elements
•
Chunking: Divide content into logical units for consistent modular structure
– Page is basic (and essential) unit for presentation and WWW (Tim said so)
•
Draw diagrams that show site structure
•
Create rough outlines of pages with list of core navigation links
•
Analyze system by testing organization interactively with real users
•
Revise as needed
Site Structure
•
How information elements of site organized
– “Conceptually”, i.e., the information architecture
– As presented to the user:
•
•
•
Through information presentation(s) generally
Navigation elements reinforce
Mental model
– How user thinks about (forms an internal representation of) site
– An important issue in interactive systems, not covered much by Shneiderman
– Both:
•
Conceptual structure of the domain of information/knowledge presented by site
–
•
•
(or more task for interactive systems generally)
Navigational structure of site
Usually, “site structure” ~= “mental model” ~= hierarchy
– Which is, of course, only an approximation
•
Much said in “popular” design literature about “site structure”, but it boils
down to hierarchies
– Because (again) the web is not hypertext – simple “goto” relations only for link
structure and navigation
– Because logn is powerful! – as all computer scientists know!
A “Browse Interface”
• Recall what you know about menus …
• Note correspondence with hierarchy of
web pages
• Call it a “browse interface” to the web
site contents, hierarchically structured
content, or whatever, much of what is
relevant to menu design is relevant
here
– Wide vs. shallow, number of alternatives,
importance of menu labels, etc.
• Note that the mental model follows in
part from interaction with content and
structure
Site Use in Practice
• In practice, typically sites use all of above:
– Site hierarchy with standard navigational links
– Topical (“see also”) links to create a web
• And user “navigates” through (or forages in) site for information
– Using both navigational links and search
Site Search as Navigation
•
“Conceptually properly placed” items still, of course, need to be accessed
– Proper and useful info. arch. (categorization, keywords, etc.) important in search
•
Despite efficiencies of hierarchies, pages often (must) be accessed through
search facilities
– Implications for information architecture: Can’t handle everything in conceptual structure
– Implications for navigation: Allow search, deal with orientation (more later)
•
See practical limitations of “browse interface”
Structure - Books and Web Pages
•
Modern book design and typography done within
constraints of expectations for books
– Margins, white space, page nums, index, toc, …
– Ancient book design was not better
•
Constraints (conventions) are result of long
process of often trial and error evolution of form
– And most evolution eliminates bad ideas
– “Prefer the standard to the offbeat”
•
Chicago Manual of Style
•
Within constraints still possible to be creative
•
L&H point out that book design is in fact
facilitated (“enabled”) by established conventions
•
Web is at fairly early (or “adolescent”, L&H) stage
in development of conventions
– Though not infancy – people learn, medium adapts
•
A lot of really bad stuff is gone, but some remains
Page Structure – and Navigation
• Relevant as it affects navigation
• Will look at “forms”, or layouts for pages here, and more about
aesthetics, etc. next time
L&H: “Canonical Form in Web Pages”
Where to put things on pages and why
• Pictorial composition
– For, e.g., home pages
– From art composition theory
• Middle and corner of plane
attract early attention
– “Rule of thirds”
• Center of interest within a grid
that divides both dimensions in
thirds
• Text reading patterns typically
more useful
– “Guttenberg Z”, “reading gravity”
• Attention flows down a page
with reluctance to reverse
downward scanning
Page Scanning: Empirical Evidence
• “Know thy user … empirically”
• Eye-tracking studies by
– Poynter Institute
(http://eyetrack.poynter.org/)
• Readers start scanning with many
fixations in upper left of page
• Gaze then follows Gutenberg Z pattern
down page
• Only later does typical reader lightly
scan right of page
– Jakob Nielsen
(http://www.useit.com/eyetracking/)
• Intense fixations across top, then, down
left edge of page – “F pattern”
• Combination (learned) reading pattern
and (learned) web page reading
Eye Tracking Studies
• Eye tracking well-known technique
for inferring attention
– eyetools.com focuses on web usability
• Record eye gaze, and map time or
number of fixations to psuedo-color
– E.g., “golden triangle” below
Eye Tracking Studies
• “F-Shaped Pattern for Reading Web
Content”
–
–
http://www.useit.com/alertbox/reading_pattern.html
Nielsen, 2009, Eyetracking Web Usability
• Three components of web page
reading (in general, and depends on
site and task):
– First, a horizontal movement
•
Across upper part of content area
– Next, second horizontal movement
•
Shorter area than first
– Finally, vertical movement
• Often slow and systematic
– Solid stripe on eyetracking heatmap
• Or slower
– Spottier heatmap
Eye Tracking Studies
• “F-Shaped Pattern for Reading Web
Content”
–
–
http://www.useit.com/alertbox/reading_pattern.html
Nielsen, 2009, Eyetracking Web Usability
• Three components of web page
reading (in general, and depends on
site and task):
– First, a horizontal movement
•
Across upper part of content area
– Next, second horizontal movement
•
Shorter area than first
– Finally, vertical movement
• Often slow and systematic
– Solid stripe on eyetracking heatmap
• Or slower
– Spottier heatmap
F-pattern only a General Shape
• Left: “About us” section of corporate web site
• Mid: Product page on e-commerce site
• Right: Search engine results page (SERP)
Some Implications of F-pattern
• Demonstrates need to not create text,
etc., as if in printed document
– Users don't read text thoroughly in a word-byword manner
– Exhaustive reading rare, especially when
users conducting search
• First two paragraphs must state most
important information.
• Start subheads, paragraphs, and bullet
points with information-carrying words
– Words that users will notice when scanning
down left side of content in final stem of their
F-behavior.
User’s Expectations of Web Pages
• Users have viewed a lot of web pages
• Have developed expectations about how to efficiently find
information on a web page (and in a web site)
– Recall, information foraging discussion
• This is learned behavior, just as how to read a book is a learned
behavior
• Effective design should exploit what is known about learned
behavior
• Will see some examples
Expectations - Information Location
•
Software Usability Research Laboratory (SURL), Wichita State University
–
•
“Preliminary Examination of Global Expectations of Users’ Mental Models for E-Commerce Web Layouts”
Pretty interesting (also, next page)
–
–
New form of web pages - “cultural”, as reading
But, “Until we have a Chicago Manual of Style for the web…”
Expectations Information Location
•
Software Usability Research Laboratory (SURL), Wichita State University
L&H: A Canonical Page Design
•
Adolescence
vs. infancy
–
•
Expectations
of users
established
Can serve as
basis for page
template / grid
–
(which would
be more
detailed and
include
graphic
elements)
Current Tools Reflect Form Ubiquity
UTPA Computer Science, 2008
•
Design
provided by
tool
–
•
Content
management
system
“De facto
standard”
Current Tools Reflect Form Ubiquity
UTPA Computer Science, 2013 – and 2014!
•
Design
provided by
tool
–
Content
management
system
•
“De facto
standard” for
organization
•
Enforces
guidelines,
applies
principles
End
• .