February 23rd, 2009 |
Published in
Information Architecture
Week 5 – (Feb 23, 2009) Analysis – User Modeling, Browsing and Searching Primary Readings
Rosenfeld, Information Architecture: Chapter 7 (Navigation Systems) and 8 (Search Systems)
- Navigation adds windows and doors to the site.
- UX Design includes IA + IXD + Info Design + Visual Design + UX Engineering (collaborative design across disciplines works best — with experts blurring the lines between disciplines)
- Note the flashback reference to Gopher (strict hierarchical navigation which limited flexibility)
- Note that frames violate the page paradigm.. bad for usability, accessibility
- Navigation needs to: Balance context & flexibility
- Consists of Global, Local and Contextual navigation + supplemental nav tools such as sitemaps, indexes, guides, wizards, configurators
- Newer tools include personalization, visualization, tag clouds, collaborative filtering, and social navigation
Issues to consider when implementing search: Sear is not an IT thing. It needs to managed as an information problem — not a technical problem.
- Does the site need a search tool?
- The anatomy of a search engine.
- What should be searchable?
- Note retrieval algorithms.
- Pattern Matching: compare search string to index of content
- Recall: # relevant docs retrieved/#relevant docs in the collection
- automatic stemming: expand search term to include other terms with same root (stem)..for higher recall
- Precision: # relevantdocs retreived/# total docs in collection
- Search using meta data results in higher precision
- These terms are inversely related… can’t have your recall and precision too
- Document Matching: using a good doc as the basis for additional searches
- Returning docs with similar meta data
- Collaborative filtering and citation search
- Query Builders: spell-checkers, phonetic tools, stemming tools, natural language processing, controlled vocabulary and thesauri
- Careful how you present search results.
- display less for people who know what they want; more for people who aren’t sure.
- Consider the design of the search interface: level of search expertise, type of info need, type of info being searched, amount of info being searched. Surprising note in the book: Just say no to advanced seearch — it isn’t used much, so low ROI.
Choo, C. W., Detlor, B., & Turnbull, D. (2000). Information Seeking on the Web: An Integrated Model of Browsing and Searching. First Monday, 5(2).
- Browser capabilities & other tech environment issues have a huge impact on usage patterns
- Motivations and search tactics are related
- Searching incorporates multiple, complementary methods of collecting quantitative and qualitative data
Tauscher, L. M., & Greenberg, S. (1997). Revisitation patterns in World Wide Web navigation. Paper presented at the ACM SIGCHI ‘97, Atlanta, GA.
- Designing history mechanisms in browsers — using empirical data as a foundation
- Showing the last few recently visited URLs with dupes removed is helpful. Most browsing is to previously viewed pages (58%)
Secondary Readings
Bates, M. After the dot-bomb: Getting Information Retrieval Right This Time. First Monday. 2002.
Kobayashi, M., & Takeda, K. (2000). Information Retrieval on the Web. ACM Computing Surveys, 32(2).
Maglio, P., & Barrett, R. (1996). How to Build Modeling Agents to Support Web Searchers. Paper presented at the Sixth Internation Conference on User Modeling, New York.
Hearst, M. (2000). Next Generation Web Search: Setting Our Sites. Bulletin of the IEEE Computer Society Technical Committee on Data Engineering
February 16th, 2009 |
Published in
Information Architecture
1. Rosenfeld, Information Architecture: Chapter 9. Thesauri, Controlled Vocabularies, and Metadata
- Metadata: data about data and documents/assets. Hooks used by software and vocabulary systems to deliver meta data-driven websites
- Controlled Vocabularies: a defined subset of natural language
- Synonym ring: a list of equivalent terms (may not be true synonyms): dramaticlly improve recall – but decrease precision.
- Authority file: a list of preferred terms. Useful for authors and indexers.Good for ‘teaching’ a common language, good for facilitating switch between search and browse.
- – Term rotation example: aspirin, see Bayer
- Classification scheme (Taxonomies): hierarchical relationships (broader/narrower) defined, like Dewey/LC. Can be use front-end (yahoo-like browse function) or backend (tool for IAs to organize and tag documents)
- Thesaurus: a model of equivalence, hierarchicl, associative relationships between concepts used to facilitate information retrieval.
- –Prefered term/Variant term, Broad/Narrow term, Related term, Use (U), Use For (UF), Scope Note (SN – definition of preferred term)
- Example site using thesaurus: PubMed from NLM
- Semantic relationships: Equivalence, Hierarchical, Associative.
- Preferred Terms:
- Term form (standardization having to do with grammar, spelling, singular/plural, abbreviation/acronyms)
- Term selection
- Term definition
- Term specificity
- Polyhierarchy
- Faceted Classification. S.R. Ranganathan.
- Five universal facets (dimensions) proposed by SRR: personality, matter, energy, space, time
- Common facets in busines world: topic, product, document type, audience, geography, price
- see Wine.com for faceted classification.
2. Morrison, J. B., Pirolli, P., & Card, S. K. (2001). A Taxonomic Analysis of What World Wide Web Activities Significantly Impact People’s Decisions and Actions. Proceedings of CHI 2001, Seattle, WA.
- Defining and building a set of tasks that represent the real user behaviors so that those behaviors can be modelled and studied.
- Purpose Taxonomy (Compare/choose, Find, Understand), Method taxonpmy (collect, find, monitor, explore),
- Content Taxonomy (Product Info & Purchase, Medical, People, Travel, Education, Job search).
3. Wilson, T. D. (2000). Human Information Behavior. Informing Science: Special Issue on Information Science Research, 3(2).
- I appreciate the definition of “knowledge” as something that is unknowable except to the knower. Therefoer, there is no such thing as a “Knowledge Management System”. Only informaiton about knowledge cna be transmitted. Knowledge management systems are really just information management systems.
- The idea that researchers in a well-defined and researched field like organic chemistry might have less need for a “skilled intermediary” and are more prone to be effective independent users of internet search engines and online search systems is curious.
- It seems that the premise is that these researchers would be beter at assigning appropriate metadata to the descreet documents — allowing for easier retrieval. That may or may not be true, as researchers may or may not think like IA’s or catalogers.
- I also am curious to see what Palmer reported from interviews (1991) about male/female diferences in information behavior.
- It’s interesting that in the 1980’s the author noted a shift from system-centered to person-centered and quantitative to qualitative approaches to the study of information seeking behavior.
4. Millen, D. (2000). Rapid Ethnography: Time Deepening Strategies for HCI Field Research. Paper presented at the DIS ‘00, Brooklyn, NY.
- Understanding users and their activities quickly. Focus on context of use, interrelationships between users in work groups.
- Ethnographer is a cultural broker — a translator. Use key informants, and a field guide (person in the study group who can help focus researchers).
5. Krug, Steve. “How do we really use the web?” from Don’t Make Me Think! A Common Sense Approach to Web Usability. 2000. QUE.
- Web use compared to looking at t billboard going by at 60mph.
- We often scan web pages.
- We satisfice (choose the first reasonable option).
- We muddle through without understanding how things work. (using sites effectively in ways never intended)
6. Smart, K. L., Rice, J. C., & Wood, L. E. (2000). Meeting the Needs of Users: Towards a Semiotic of the Web. IEEE Technology and Teamwork, 593-605.
- 6 elements often used to describe/evaluate web designs:
- Typography (use of typeface, layout, color to convey meaning of text)
- Site structure/cognitive design (how information is organizeed on a site)
- Medium use (the appropriate/optimal use of Web features)
- Message content (narrative style)
- Appeal
- Accessibility
- See table for a list of questions used to guide effective web design. (page 603)
February 9th, 2009 |
Published in
Information Architecture
Structure & Memorability of Websites. Modjeska & Marsh (1997)
- Strongly hierarchical sites are more usable
- Nodes high in the hierarchy (closer to the root) are more memorable
- Strongly hierarchical sites are perceived as smaller than weakly hierarchical sites.
- Site size has little impact on user nav & mental models
Boxes and Lines over Bullets and Arrows: Deliverables that Clarify, Focus and Improve Design. Fulcher, Glass, Leacock
- Concept Maps: capturing users’ mental models
- Wireframes & Storyboards: great for iterative prototyping.
- Flow Maps: navigation & high-level product behavior
- Detailed Mockups & Functional Specs: Production-ready materials
Web Page Design: Implications of Memory, Structure and Scent for Information Retreival. LArson & Czerwinski.
- Balancing breadth and depth ouperforms broad & shallow web structures
February 9th, 2009 |
Published in
Information Architecture
Continued notes from Information Architecture for the World Wide Web by Peter Morville& Lou Rosenfeld.
Classification is difficult because: language is ambiguous; heterogeneity (collections of unrelated parts)(variety of granularity, format), differences in perspectives (mental models of labeling and organization), internal politics.
Organization systems = schemes (shared characteristics of content) + structures (kinds of relationships between content items & groups)
Simple Schemes:
- Alphabetical – great for known-item searching (phone book)
- Chronological – (archive of press releases)
- Geographical – (map-based select a location)
Ambiguous (subjective) Schemes: support serendipitous searching –like Dewey, LC
- Topic
- Task
- Audience
- Metaphors (requires a lot of familiarity and may accidentally limit applications online –watch scalability)
- Hybrids (shallow use of hybrid schemes may work well to define a limted set, but scalability is difficult. Group like-themes together instead of mixing a variety of schemes together)
Organizational Structures
- Hierarchy (top-down): Generally, categories are mutually exclusive, but may need to cross-reference items to boost findability. If too many items are cross-listed, the hierarchy loses value. (exclusivity vs inclusivity). Also consider balancing breadth and depth of the taxonomy (too many choices vs. too many clicks)
- taxonomy – hierarchical arrangement of categories in a user interface
- facets – different ways of looking at the same information yields differents facets
- The Database Model (bottom-up approach): enabling dynamic indexes, see also links, advanced searching (fielded searches?), filtering & sorting of search results
- Hypertext -great compliment to a strong hierarchy
Social Classification
Folksonomies are very popular. Is there evidence yet of their performance vs. traditional approaches to organization?
Most sites use a variety of organizational structures.
February 7th, 2009 |
Published in
Information Architecture
Mentioned in class:
Primary Readings for next week
- Rosenfeld, Information Architecture: Chapters 4 & 5
- Modjeska, D., & Marsh, A. (1997). Structure and Memorability of Web Sites. Toronto: Computer Science Research Institute of the University of Toronto.
- Fulcher, R., Glass, B., & Leacock, M. (2001). Deliverables that Clarify, Focus, and Improve Design. Examples and resources from a talk given at the 2002 Annual Conference of the Usability Professionals’ Association.
Secondary Readings
February 7th, 2009 |
Published in
Information Architecture
Continued notes from Information Architecture for the World Wide Web by Peter Morville& Lou Rosenfeld.
- Top-down IA: Determine most common needs and design the site to meet those needs
- Bottom-up IA: Embedded in the guts of the content; the structure supports searching and browsing. Note that users may often skip the top-down elements (menus/categories) to do searches from outside engines and on-site search tools
- Take a look at Keith Instone’s nav stress test to evaluate a site’s bottom-up IA
4 categories of IA Component:
- Organization Systems (by subject, chronology…)
- Labeling Systems (terminology)
- Navigation Systems (how we browse)
- Searching Systems
Browsing aids:
- organization systems
- site-wide & local navs
- sitemps, TOC’s
- Site indices, guides & wizards
- contextual nav
Searching aids:
- search interface
- query language – the grammar of the search, incl booleans, ability to search on criteria (author….)
- query builders – enhanced search via spell check, synonym matches, concept searching…
- retrieval algorithms (page ranking)
- Search zones (allowing search of a subset)
- search results (presentation, rank, sort, clustering)
Content & Tasks
- Headings
- embedded links
- embedded metadata
- chunks, lists
- sequential aids (task road map, how long until task is finished)
- identifiers (where am I: breadcrumbs)
Invisible components of IA
- controlled vocabulary & thesauri
- retreival algorithms
- expert-ranked results within searches (results +espert determines best resources, weighing those in the search results)
February 7th, 2009 |
Published in
Family
Couldn’t find my purse the other day (frantic). So my 6yo daughter packs her wallet with $12 (for my lunch), pictures of her and a sweet note to mommie. oh my. Later my daughter said that she should’ve included a note for the police: “my mommie is allowed to drive. She just can’t find her wallet today.”
My daughter is amazing.
February 7th, 2009 |
Published in
Design, Information Architecture, Usability
- The Magical Number Seven, Plus or Minus Two: Some Limits on Our Capacity for Processing Information. by George A. Miller
(not to be confused with a mandate on number of items in a menu. The 7+-2 number only applies to “unidimensional
stimuli (pitches, loudness, brightness, etc.) and also a limit for immediate recall“.
- Cowan, N. (2001) The Magical Number 4 in Short-term Memory: A Reconsideration of Mental Storage Capacity. Behavioral and Brain Sciences 24 (1)
- J.L. Doumont “Magical Numbers: The Seven-Plus-or-Minus Two Myth,” (Interface) IEEE Trans. Prof. Comm., vol. 45, pp. 123-127, 2002.
- Psychophysics (Wikipedia)
- Fitts’ law:a model of human movement which predicts the time required to rapidly move to a target area, as a function of the distance to the target and the size of the target.
- Hick-Hyman law: the time it takes for a person to make a decision as a result of the possible choices he or she has
- Cognitive bias:a person’s tendency to make errors in judgment based on cognitive factors
- The Stanford Persuasive Technology Lab: “Captology” – the study of computers as persuasive technology
- Ware, C. (2000). Information visualization: Perception for design. San Francisco, CA: Morgan Kaufmann.
- Wickens, C. D., Gordon, S. E., & Liu, Y. (1998). An introduction to human factors engineering. New York, NY: Addison-Wesley
- Interaction Design Association (IxDA)
- Delicious collection from Marla Erwin
February 2nd, 2009 |
Published in
Usability
Introduction to Usability (Spring 2009) – Professor Randolph Bias
To Do:
Physiology & Users
Retina – nerve cells that fire in response to stimulation — send info through optic nerve.
We are more sensitive to light than color; more sensitive to green than blue or red.
Reading is a mapping problem. Letters–>mental map of meanings.
bed – one of the few English words that looks like what it is.
Eye movements are jumpy: fixation — saccades — regressions — return sweeps.
Span of perception = 12 letter spaces for good readers; 6 for poor readers
This is important for line length in newspapers.
Span of recognition: 1.21/senior high, 1.33/college
In English, need about 40 letter-to-sound rules
Interesting test: Say the color of the word: BLUE (in green ink), RED (in blue ink), GREEN (in red ink)
Memory: short-term, long-term.
Remember that the 5-9 rule applies to memory – not a menu list that is visible. Don’t mis-apply these rules. A long menu may well be very usable.
Memory task: shows primacy effect, recency effect. Show 10 3-letter combinations of consonant-vowel-consonant. Ask participants to recall them. Do the same thing but include intervening task of counting backwards by 3’s.
Results show arc – first item and last items are best remembered by all.
February 2nd, 2009 |
Published in
Usability
Introduction to Usability (Spring 2009) – Professor Randolph Bias
Usability + Schedule + Functionality = project
The 1995 World Cup was won by New Zealand. An example of excellent participatory design. The process built the best boat.
To Do:
