CS459559 HumanComputer Interaction

1
CS459/559Human-Computer Interaction

• Conceptualizing Interaction
• 9-3-2007
• Prof. Searleman, jets_at_clarkson.edu

2
Outline

• Understanding the Problem Space
• Conceptualizing the Design Space
• HW1 posted, due Wednesday, 9/5/07
• teams?
• handheld device?

3
Chapter 2 Understanding and conceptualizing
interaction
4
Understanding the problem space

• What do you want to create?
• What are your assumptions?
• What are your claims?
• Will it achieve what you hope it will? If so,
  how?

5
A framework for analysing the problem space

• Are there problems with an existing product or
  user experience?
• Why do you think there are problems?
• How do you think your proposed design ideas might
  overcome these?
• When designing for a new user experience how will
  the proposed design extend or change current ways
  of doing things?

6
An example

• What do you think were the main assumptions made
  by developers of online photo sharing and
  management applications, like Flickr?

7
Assumptions and claims

• Assumptions
• Able to capitalize on the hugely successful
  phenomenon of blogging
• Just as people like to blog so will they want to
  share with the rest of the world their photo
  collections and get comments back
• People like to share their photos with the rest
  of the world
• A claim
• From Flickrs website (2005) is almost
  certainly the best online photo management and
  sharing application in the world

8
From problem space to design space

• Having a good understanding of the problem space
  can help inform the design space
• e.g., what kind of interface, behavior,
  functionality to provide
• But before deciding upon these it is important to
  develop a conceptual model

9
Conceptual Model

• The most important thing to design is the users
  conceptual model. Everything else should be
  subordinated to making that model clear, obvious,
  and substantial. That is almost exactly the
  opposite of how most software is designed
  David Liddle, 1996, p. 17
• envision the proposed product based on users
  needs and identified requirements (iterative
  testing with users)

10
Conceptual model

• Need to first think about how the system will
  appear to users (i.e. how they will understand
  it)
• A conceptual model is
• a high-level description of how a system is
  organized and operates. (Johnson and Henderson,
  2002, p. 26)

11
What is and why need a conceptual model?

• Not a description of the user interface but a
  structure outlining the concepts and the
  relationships between them
• Why not start with the nuts and bolts of design?
• Architects and interior designers would not think
  about which color curtains to have before
  deciding where the windows will be placed in a
  new building
• Enables designers to straighten out their
  thinking before they start laying out their
  widgets (p. 28)
• Provides a working strategy and a framework of
  general concepts and their interrelations

12
Helps the design team

• Orient themselves towards asking questions about
  how the conceptual model will be understood by
  users
• Not to become narrowly focused early on
• Establish a set of common terms they all
  understand and agree upon
• Reduce the chance of misunderstandings and
  confusion arising later on

13
Conceptual Model Design

• Once a set of possible ways of interacting with
  the system or device has been identified, design
  of a conceptual model needs to be thought through
  with concrete solutions behavior of the
  interface, interaction styles, look feel, etc.
• Another way of designing a conceptual model is to
  select an interface metaphor.
• What is a metaphor?

14
Metaphor vs. Idiom

• Cooper
• implementation-centric interface based on
  understanding how things work
• metaphoric interface based on intuiting how
  things work
• idiomatic interface based on learning how to
  accomplish things
• Axiom All idioms must be learned good idioms
  need to be learned only once.

15
Main components

• Major metaphors and analogies that are used to
  convey how to understand what a product is for
  and how to use it for an activity.
• Concepts that users are exposed to through the
  product
• The relationships between the concepts
• e.g., one object contains another
• The mappings between the concepts and the user
  experience the product is designed to support

16
A classic conceptual model the spreadsheet

• Analogous to ledger sheet
• Interactive and computational
• Easy to understand
• Greatly extending what accountants and others
  could do

www.bricklin.com/history/refcards.htm
17
Why was it so good?

• It was simple, clear, and obvious to the users
  how to use the application and what it could do
• it is just a tool to allow others to work out
  their ideas and reduce the tedium of repeating
  the same calculations.
• capitalized on users familiarity with ledger
  sheets
• Got the computer to perform a range of different
  calculations and recalculations in response to
  user input

18
Another classic

• 8010 Star office system targeted at workers not
  interested in computing per se
• Spent several person-years at beginning working
  out the conceptual model
• Simplified the electronic world, making it seem
  more familiar, less alien, and easier to learn

Johnson et al (1989)
19
The Star interface
20
Interface metaphors

• Designed to be similar to a physical entity but
  also has own properties
• e.g. desktop metaphor, search engine
• Exploit users familiar knowledge, helping them
  to understand the unfamiliar
• Conjures up the essence of the unfamiliar
  activity, enabling users to leverage of this to
  understand more aspects of the unfamiliar
  functionality
• People find it easier to learn and talk about
  what they are doing at the computer interface in
  terms familiar to them

21
Benefits of interface metaphors

• Makes learning new systems easier
• Helps users understand the underlying conceptual
  model
• Can be innovative and enable the realm of
  computers and their applications to be made more
  accessible to a greater diversity of users

22
Problems with interface metaphors (Nelson, 1990)

• Break conventional and cultural rules
• e.g., recycle bin placed on desktop
• Can constrain designers in the way they
  conceptualize a problem space
• Conflict with design principles
• Forces users to only understand the system in
  terms of the metaphor
• Designers can inadvertently use bad existing
  designs and transfer the bad parts over
• Limits designers imagination in coming up with
  new conceptual models

23
Activity

• A company has been asked to design a
  computer-based system that will encourage
  autistic children to communicate and express
  themselves better.
• What type of interaction would be appropriate to
  use at the interface for this particular user
  group?

24
Summary points

• Need to have a good understanding of the problem
  space
• specifying what it is you are doing, why, and how
  it will support users in the way intended
• A conceptual model is a high-level description of
  a product
• what users can do with it and the concepts they
  need to understand how to interact with it
• Decisions about conceptual design should be made
  before commencing any physical design
• Interface metaphors are commonly used as part of
  a conceptual model