Evaluating etravel sites with the use of design patterns

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Evaluating e-travel sites with the use of design
patterns

• Yannis Psaromiligkos (jpsa_at_teipir.gr)
• Petros Georgiakakis (geopet_at_unipi.gr)
• Symeon Retalis (retal_at_unipi.gr)

TEI Piraeus University of Piraeus
Computer Supported Learning Engineering
Laboratory http//cosy.ted.unipi.gr
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Motivation why yet another method for expert
based evaluation?

• The problem

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Motivation why yet another method for expert
based evaluation?

• To help novice evaluators in usability evaluation
  
• not always look for usability experts in the
  specific work-domain but providing a novice
  evaluator the expert view
• Novice evaluators need
• Conceptual framework about the domain knowledge
• Detailed scenario-based procedure in inspecting
  the system
• Provision of best design practices within the
  context of use
• Detailed forms for writing a usability report

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Overview

• Few words about patterns
• Evaluating a web-based system using DPs
• DEPTH method
• Criticism of DEPTH

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Bus stops
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The Bus Stop
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What is a design pattern?
A Solution to a Problem in a Context
Alexander defines a pattern as follows "....
Each pattern describes a problem which occurs
over and over again in our environment, and then
describes the core of the solution to that
problem, in such a way that you can use this
solution a million times over, without ever doing
it the same way twice" Alexander, C.,
Ishikawa, S., Silverstein, M., Jacobson, M.,
Fiksdahl-King, I., Angel, S. (1977). A Pattern
Language. Oxford University Press, New York.
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Alexanders original ideas

• offering a set of conceptual resources that
  ordinary people could use in (re)shaping their
  environment.
• His work provides a principled, structured but
  flexible resource for a lingua franca in design.
• He strikes the right balance between rigor and
  prescriptiveness - offering useful guidance
  without constraining creativity and providing
  helpful foci for design.

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UI Design Pattern Languages

• 57 Web 25 GUI Design patterns - Martijn van
  Welie-www.welie.com,Interaction Design
  Patterns.htm
• 30 Design patterns - Hypermedia Design Patterns
  Repository http//www.designpattern.lu.unisi.ch/Pa
  tternsRepository.htm
• 90 Design patterns - Douglas K. Van Duyne, James
  A. Landay, Jason I. Hong, The design of sites,
  Addison Wesley July 2002
• The Interaction Design Patterns Page - pattern
  languages for interaction design (of which user
  interface design is a subset), and a few links to
  more general papers that may be of use to
  interaction designers.
• http//www.pliant.org/personal/Tom_Erickson/Intera
  ctionPatterns.html
• 30 UI Patterns Jenifer Tidwell http//www.time-tri
  pper.com/uipatterns/

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The Product Configurator Design Pattern
From Welie

• Problem Users want to configure the product they
  may intend to buy
• Use When You want users to get more
  enthousiastic about a product by letting them
  'control' the product and kind of 'personalize'
  it.

Source www.nickie.com
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The Product Configurator Design Pattern
From Welie

• Solution Allow users to configure a product
  using a direct and visual version of the
  configured product
• Configuring is usually done is several steps
  because there may be several aspect of the
  product that can be configured, e.g. the colour,
  material, writings, weels etc.
• The product configurator is therefore a Wizard
  where every configurable aspect of the product is
  handled in a single step.
• Additionally there may be a 'buy' or 'order' step
  that leads to some additional steps for the
  wizard.
• Since the steps of the process are usually not
  dependent on each other, Tabs can also be used to
  set each aspect instead of using a Wizard.

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Patterns Can

• Capture expert design practice within specific
  context
• Provide common nomenclature for designers
• Provide shorthand for effectively communicating
  complex principles
• Help documentation and justification of the
  rationale
• Capture the most important aspects of a problem
  solution in a standard format with a formalism
• Show multiple examples of solutions
• Become a tool for collaboration among peers who
  are interested in designing activities

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What Is the Relation Between Design Patterns and
Usability?

• HCI design patterns are user centered design
  patterns which by nature are focused on
  usability
• HCI design patterns have been created with some
  underlying values in the same lines with
  Alexander (The Quality without a Name).
• implementation of a design pattern varies
• So lets check the implementation based on a
  design pattern!

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Motivation in using Design Patterns for Usability
Evaluation Purposes

• We try to minimize the time spent for the
  preparatory phase of an inspection usability
  study
• To create the re-usable scenarios and tasks to be
  checked by an evaluator for a specific genre
• To help novices in usability evaluation
• not always try to look for usability experts or
  work-domain experts but having handy the
  expert view
• Patterns contain the distilled knowledge of an
  expert as well as her tacit design knowledge
• HCI design patterns are the means for expressing
  the ideal functionality of a interactive
  application in a justified and not prescriptive
  way.

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DEPTH method at a glance
Preparatory phase
Execution phase
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DEPTH Execution Process overview
Choose genre
Choose features
Assign weights
Scenario-1
Scenario-n
Walkthrough
Walkthrough
Step 1
Step n
Step 1
Step n


Design Pattern - n
Design Pattern - 1

Answer to Questions Rate Quality of Feature
Answer to Questions Rate Quality of Feature
Overall opinion about the Nielsens heustistics
Report production
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theory and practice? (I)

• We have evaluated
• E-travel sites
• 18 MSc students basic knowledge of HCI
• Identified all problems that experts had already
  spotted
• Proposed solutions to the problems
• Proposed changes to design patterns

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Seeing selecting the functionality of the
system under evaluation
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View Execute the Scenarios
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Linking scenario with pattern
http//www.welie.com/patterns/showPattern.php?patt
ernIDshopping-cart
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theory and practice? (II)

• We have also evaluated
• Learning Object Repositories
• We have created scenarios for
• Wiki-systems, like TikiWiki
• Synchronous Web Conferencing Systems like
  netmeeting, Centra
• Personalised web-based educational systems, like
  INSPIRE

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Methods Similarities Advantages

• A similar example of expert evaluation using
  design patterns has been performed by Van Welie
  for evaluating the general usability of web
  museums without user involvement.
• He analyzed the major sections of the websites in
  order to recognize patterns that had been
  applied.
• He commented that the evaluation is easier when
  the evaluator knows the pattern collection
  available
• The idea of Re-usable scenarios exist in SUE,
  MILE, eLSE methods, Matera, Costabile,
  Garzotto, Paolini,Ardito, Buono, Lanzilotti, et
  al.
• they foster re-usability of inspection scenarios
  standardization-uniformity in scenarios
  presentation/writing

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Methods Disadvantages

• Design patterns are not that many but the field
  is still evolving
• Will there always be a good design pattern to
  validate all areas of interest of various system
  genres?
• Difficult to write good scenarios
• Varying levels of generality and completeness
  how narrow or broad it should be (Kuutti 1995).
• Make use of existing design guidelines

http//www.usability.gov/pdfs/guidelines.html
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The DEPTH Evaluation Tool

• Scenarios repository
• Scenarios are related to functionality and
  patterns
• Patterns repository
• Patterns are arranged by genre functionality
• There are genre independent patterns
• Reporting system
• Create Update a report that contains
  Qualitative Quantitative Data

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Future plans

• To use it in more evaluation studies
• We have started with the evaluation of Learning
  Management Systems and Collaborative Tools
• To answer to questions about
• The granularity of the scenario
• a scenario can be highly scripted or loosely
  defined. One of the main difficulties is how to
  create such scenarios.
• The use of patterns that are genre independent
• To use DEPTH for applying Design Patterns and
  revising design patterns.

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Conclusion

• The use of design patterns has potential
• to capture usable design knowledge,
• build bridges between practical problems and
  research-based evidence, and
• help designers see both the wood and the trees
  when they are engaged in design

The most important part of a sucessfull design is
the underlying conceptual model. The hard part
of design formulating an appropriate conceptual
model and then assuring that everything else be
consistent with it. Donald Norman
M.C. ESCHER
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Questions?
thanks for your attention
Yannis Psaromiligkos (jpsa_at_teipir.gr) Petros
Georgiakakis (geopet_at_unipi.gr) Symeon Retalis
(retal_at_unipi.gr)
Computer Supported Learning Engineering
Laboratory http//cosy.ted.unipi.gr
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Forming a design pattern language
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Eliciting a pattern