Archive for March, 2009

Pareto’s Principle: 80/20

March 31, 2009

A high percentage of effects in any large system are caused by a low percentage of variables.

E.g. 80% of Web traffic is caused by 20% of Web sites

Aka Juran’s principle, Vital few, Trivial Many Rule

Based on Vilfredo Pareto (economist); seminal work: Quality Control Handbook (1951) by Joseph M Juran (ed.)

Tacit knowledge – Explicit knowledge

March 26, 2009
  • Explicit knowledge is relatively easy to capture and store in databases and documents. It is shared with a high degree of accuracy. Explicit knowledge can be either structured or unstructured:
  • Structured – Individual elements are organized in a particular way or schema for future retrieval. It includes documents, databases, and spreadsheets.
  • Unstructured – The information contained is not referenced for retrieval. Examples include e-mail messages, images, training courses, and audio and video selections.
  • Tacit knowledge is knowledge that people carry in their minds and is, therefore, difficult to access. Often, people are not aware of the knowledge they possess or how it can be valuable to others. Tacit knowledge is considered more valuable because it provides context for people, places, ideas, and experiences. Effective transfer of tacit knowledge generally requires extensive personal contact and trust.


Tacit Knowledge (Polanyi)

March 26, 2009

The concept […] comes from scientist and philosopher Michael Polanyi […] to name a form of knowledge that is apparently wholly or partly inexplicable.

Tacit knowledge is not easily shared. One of Polanyi’s famous aphorisms is: “We know more than we can tell.” Tacit knowledge consists often of habits and culture that we do not recognize in ourselves. In the field of knowledge management the concept of tacit knowledge refers to a knowledge which is only known by an individual and that is difficult to communicate to the rest of an organization. Knowledge that is easy to communicate is called explicit knowledge. […] Tacit knowledge is considered more valuable because it provides context for people, places, ideas, and experiences. Effective transfer of tacit knowledge generally requires extensive personal contact and trust. The process of transforming tacit knowledge into explicit knowledge is known as codification or articulation.

Sourced from Wikipedia, paraphrased by twobenches

Implicit (tacit) knowledge Explicit knowledge

March 26, 2009

“[What I know of my children] is too long and deep to be exhausted in words, too twisty, entangled, and intertwingled to be made completely explicit.”
David Weinberger (2007): Everything is Miscellaneous, Times Books, New York

Different Types of IA/UX Research

March 25, 2009
  1. Protocol-generation techniques
    – include various types of interviews (unstructured, semi-structured and structured), reporting techniques (such as self-report and shadowing) and observational techniques
  2. Protocol analysis techniques
    – are used with transcripts of interviews or other text-based information to identify various types of knowledge, such as goals, decisions, relationships and attributes. This acts as a bridge between the use of protocol-based techniques and knowledge modelling techniques.
  3. Hierarchy-generation techniques
    – such as laddering are used to build taxonomies or other hierarchical structures such as goal trees and decision networks.
  4. Matrix-based techniques
    – involve the construction of grids indicating such things as problems encountered against possible solutions. Important types include the use of frames for representing the properties of concepts and the repertory grid technique used to elicit, rate, analyse and categorise the properties of concepts
  5. Sorting techniques
    – are used for capturing the way people compare and order concepts, and can lead to the revelation of knowledge about classes, properties and priorities.
  6. Limited-information and constrained-processing tasks
    – are techniques that either limit the time and/or information available to the expert when performing tasks. For instance, the twenty-questions technique provides an efficient way of accessing the key information in a domain in a prioritised order
  7. Diagram-based techniques
    – include the generation and use of concept maps, state transition networks, event diagrams and process maps. The use of these is particularly important in capturing the “what, how, when, who and why” of tasks and events.

Sean Bechhofer: Knowledge Elicitation (PDF)

Triadic Knowledge Elicitation: 3 Card Trick

March 25, 2009

• Select 3 cards at random
• Identify which 2 cards are the most similar?
– Why?
– What makes them different from the third card?
• Helps to determine the characteristics of our classes
• Picking 3 cards forces us into identifying differences between them
– There will always be two that are “closer” together
– Although which two cards that is may differ depending on your

Sean Bechhofer: Knowledge Elicitation (PDF)

UxD is applied Social Sciences

March 20, 2009

“There is a lot more that we can learn from the social sciences about human behaviour. They have tools and models for understanding human behaviour that haven’t been integrated in our processes yet. In a lot of ways, UxD is applied social science.”
Jesse James Garrett

User journeys as narratives: From theme to detailed information

March 19, 2009

Users can take very different journeys within the same domain and every user journey is a narrative in its own right. A consistent structure of the website and its different sections is key to meaningful journeys that are effective and satisfying. Top levels introduce the big idea first and offer choices to proceed. From every level, a journey can proceed horizontolly, i.e. to related aspects, or vertically, i.e. to subordinate levels that provide greater detail. As every level and branch provides a different perspective on the theme, user itineraries can potentially become very complex. For information heavy sites, consider providing tools that allow users “berry picking”, i.e. managing information collected over the course of the journey.

Meaningful encapsulation

March 18, 2009

Meaningful encapsulation: every page must make sense as it stands on the screen.


March 12, 2009

My personal take on Agile Prototyping/Development: The ability and the necessity to constantly check horizontally (what I do makes sense across all segments of the project) and vertically (what I do makes sense from a high level point of view).