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User Interfaces
EECS 3461
Fall 2020
Resource 01-E, Interaction Design and Technosocial Systems I
© Melanie Baljko
Starting Point
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the design of interactive systems takes place in situated
contexts
one of the situated contexts is based in product
development for consumer markets, but many other
situated contexts exist
to open the discussion of these other situated contexts, we
will use the open source movement as an entry point
to get to the concept of the open source movement, we will
first follow a sequence of introductory concepts
2
Situated Contexts for Design
“On one level, design is a general human process that we
use to understand and to shape our world. …we meet the
challenges of design in specific challenges, addressing
problems or ideas in a situated context. The challenges we
face as designers today are as diverse as the problems
clients bring to us. We are involved in design for economic
anchors, economic continuity, and economic growth. We
design for urban needs and rural needs and for social
development and creative communities. We are involved
with environmental sustainability and economic policy.
agriculture competitive crafts for export, competitive
products and brands for micro-enterprises, developing new
products for bottom-of-pyramid markets and redeveloping
old products for mature or wealthy markets.” [1]
[1] Friedman and Stolterman, series forward, Adversarial Design, Carl
DiSalvo, 2012 emphasis added
3
Digital ecosystem
“A digital ecosystem is a distributed, adaptive, open sociotechnical system with properties of self-organisation,
scalability and sustainability inspired from natural
ecosystems.”[1][2]
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we’ll use this concept to frame issues of production and
consumption with respect to interactive systems
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who is engaged in producing (designing, implementing,
distributing) interactive systems? and why?
who is engaged in consuming (buying, adopting, using)
interactive systems? and why?
Ecosystem
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the concept of digital ecosystem derives from the more-basic concept of an
ecosystem, which was first developed in the 1930’s in context of ecology
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an ecosystem is typically defined as:
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ecosystems are dynamical systems that:
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“a community of living organisms in conjunction with the nonliving components of
their environment, interacting as a system”[1]
have a sense of balance (balance of population: producers and consumers)
a capacity to respond to perturbation
• to resist disturbances and stay close to its equilibrium
• to be perturbed but then to return to its equilibrium
• gain a new state of equilibrium with a different composition of components
there is much more to the conceptualization of an ecosystem, but we’ll won’t delve
into further detail here
sustainability refers to the ecosystem’s capacity to continue to exist
[1] definition from Wikipedia, which cites: Tansley (1934); Molles (1999), p. 482; Chapin et al. (2002), p. 380; Schulze et al.
(2005); p. 400; Gurevitch et al. (2006), p. 522; Smith & Smith 2012, p. G-5
Who Produces and Consumes Interactive
Systems? and Why?
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the answer to this question is complex; we’ll start with
some of the key dimensions here
6
Disciplinary Effects
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Industrial Design and Computer Science are two of the
foundational disciplines for user interfaces
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UI/UX tends to be rooted in the practice of industrial design
and ‘designerly’ practices that evolved from industrial
design (think ‘design school’)
HCI has its roots in Computer Science, combined with
Cognitive Psychology and other fields, strongly rooted in a
scientific, empirical tradition, and tends to espouse an
engineering design approach (think ‘school of engineering’)
this relates to the question of “who is involved in the
design of user interfaces and interactive systems”
7
Non-Proprietary Software
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This is a complicated space
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One dimension: do consumers need to pay?
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upfront? after a while? never?
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this is the payware ⏤ freeware continuum
Another dimension: can I take the software and riff on it?
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yes without conditions? yes but subject to some conditions?
yes but not legally? no not even if you wanted to and tried?
this is the closed-source ⏤ open-source continuum
Free and Open Source Software (FOSS) combines both
dimensions – free and open-source
8
Market and Consumerism Effects
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much of interactive system production is connected to
consumer markets:
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consumerism is:
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creating new competitive products and brands, for different
markets (e.g., bottom-of-pyramid markets)
redeveloping extant products, for mature or wealthy markets
(e.g., interactive refrigerators)
encouragement of the acquisition of goods and services
a social and economic order
connected to capitalism
the gist of the idea: getting people to buy new stuff even if they don’t
need it or want it, even if the production of the new stuff is harmful to
the environment or exploits workers
however, the production and consumption of interactive
systems does not only take place solely within the framework
of consumer markets
Industrial Design and Mass Production
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industrial design has its roots in mass production; it is a
design process applied to products that are intended to be
manufactured (as opposed to hand crafted)
thus, industrial design also has a connection to the
consumer market
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Assetization of Interactive Systems
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Companies can and do make profit via the production and
distribution of interactive systems, deployed via their own
or other distribution platforms
Companies can assetize their interactive systems as
products and services in different ways
We’ll next look at the distinction of proprietary vs nonproprietary software, which will illustrate:
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the payware ⏤ freeware continuum
the closed-source ⏤ open-source continuum
11
Proprietary Software
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has a publisher or owner
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the publisher or owner retains intellectual property rights
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the intellectual property rights typically are in the form of
copyright of the source code or patent rights
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intellectual property rights can be upheld legally
infringement of IP can result in damages
in addition to legal means, owners protect their intellectual
property rights via closed-source software (source code not
made available)
owners capitalize on their intellectual property rights in
different ways:
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license their technologies to others (for profit)
decline to license their technologies to others (to establish and
maintain market position; to have a competitive edge)
12
Case Study
Case Study: The StoryGraph vs Goodreads
”Why Goodreads is bad for books”, Sarah Manavis,
newstatesman.com,
https://www.newstatesman.com/science-tech/socialmedia/2020/08/better-goodreads-possible-bad-for-booksstorygraph-amazon
The article illustrates, via the lens of UI/UX design, some of
the dynamics of proprietary software in establishing and
holding market share
13
The Payware ⏤ Freeware continuum
Payware:
• software that is sold (can be for profit or to cover costs)
• the consumer needs to pay as a condition of use
• a key issue is enforcement:
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a provider can offer software for sale, but payment can be
circumvented
e..g., cracked software
Freemium:
• software is provided free initially, but payment is
subsequently required (for ongoing use or for additional
features)
Free:
• do not have to pay; does not imply that the source code is
available
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The Closed-source⏤Open-source continuum
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the payware ⏤ freeware continuum relates to pricing and
distribution
the closed-source ⏤ open-source continuum relates to
(ultimately) intellectual property rights
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open-source may, at the outset, appear to be an issue of the
availability of the source code, the issue does boils down to
what one can do with the source code that has been made available
15
Copyright
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copyright is a legal instrument, put into force by the Copyright
Act, a federal statute of Canada (1921, 1988, 1997, 2012)
is a type of intellectual property that gives its owner the
exclusive right to make copies of a creative work (usually not
in perpetuity, though)
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let’s assume here that the creative work refers to an interactive
system (and its various facets, including its UI)
copyright attaches automatically upon the creation of the
creative work, it does not need to be explicitly ‘claimed’
a copyright owner may decide what to do with the
copyrighted work:
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to monetize, but also may decide not to
to put their work into the public domain, uncopyrighted
• But then others can take the work and convert it into
proprietary software and then distribute it as a proprietary
product.
16
Copyleft
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copyleft is set of practices
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these practices make use of various legal instruments, but
copyleft is not itself a legal instrument
e.g., there is no “Copyleft Act” federal statute in Canada (or in
any other nation state, to my knowledge)
“Copyleft is a general method for making a program (or other
work) free (in the sense of freedom, not “zero price”), and
requiring all modified and extended versions of the program
to be free as well.” [1]
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there are different entities in the business of crafting suitable
licenses for people to use:
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the Creative Commons (a not-for-profit), provides CC-0 and
other licenses
the Free Software Foundation (a not-for-profit), provides the
Gnu General Public License (GPL)
[1] What is Copyleft?, https://www.gnu.org/copyleft/
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Open Source
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at one time referred to the open source software movement,
but now also includes open content, open collaboration, and
practices connected with knowledge commons
open source stands in tension with privatization (and
capitalism, market-economies)
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‘stands in tension’ does not mean ‘is the opposite of’ or ‘contradicts’
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e.g., some for-profit companies operate using open source
products:
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moodle is open source
eThink is a company that provides “implementation,
integration, management. and cloud-hosting services
for the open source LMS Moodle in the Higher
Education” sector
rather, the open source movement has opened up new spaces for
production and consumption
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In Summary
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•
•
•
the design of interactive systems takes place in situated
contexts
one of the situated contexts is based in product
development for consumer markets, but many other
situated contexts exist
to open the discussion of these other situated contexts, we
will use the open source movement as an entry point
to get to the concept of the open source movement, we will
first follow a sequence of introductory concepts
19
User Interfaces
EECS 3461
Fall 2020
Resource: Technosocial II
© Melanie Baljko
Topics
1.
Disciplinary areas relevant to this course
2.
Social Roles, user and stakeholder
3.
Technology Acceptance vs Technology Use: A thematic
illustration
2
1. Disciplinary areas relevant to this course
3
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Interaction design is multidisciplinary, involving many
inputs from wide-ranging disciplines and fields.
4
these are the disciplines and fields from which the course materials for
EECS3461 are drawn; a course on ‘User Interfaces’ can be taught in
many different ways
https://www.fastcodesign.com/3032719/
A “Role”-Based Perspective on User Interfaces
UX Designer (User Experience Designer)
UI Designer (User Interface Designer)
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! “designers”
concerned with how the product feels/concerned with how the
product is laid out
ensure that the product logically flows from one step to the next
if UX/UI roles separated: UI Designer ensures the UI visually
communicates the path that a UX designer has laid out; ensure a
consistent design language is applied across the product
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develops preliminary designs: wireframes, flows, mock-ups
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tools: Sketch, Illustrator, InVision, etc
Front-End Developer (UI Developer)
! “devs”
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concerned with implementation (given flows and wireframes)
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create a functional implementation of a product’s interface
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uses tools such as React.js, Angular, JavaFX, html5, etc
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Defining the Discipline of Human-Computer
Interaction (HCI)
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Grudin (2012) defines HCI broadly, to cover major threads
of research in four disciplines: human factors, information
systems, computer science, and library & information science.
For others, HCI is used narrowly, to refer to work in one
discipline (such as CS)
I use the term HCI broadly as well, to refer to work across
multiple disciplines.
8
Defining Disciplines
Grudin (2012) also provides a characterization of the related
disciplines:
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CHI (Computer-Human Interaction) is given a narrower focus than
HCI; associated primarily with computer science, the Association for
Computing Machinery Special Interest Group (ACM SIGCHI), and
the latter's annual CHI conference.
HF&E: ‘Human factors’ and ‘ergonomics’ often are used
interchangeably, and refer to the discipline as HF&E. (Some writers
define ergonomics more narrowly around hardware.)
IS (information systems) refers to the management discipline that
has also been labeled data processing (DP) and management
information systems (MIS).
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common parlance is to refer to organizational information systems
specialists as IT professionals or IT pros.
LIS (library and information science) represents an old field with a
new digital incarnation that includes important HCI research.
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Why is it important to identify disciplines?
I will return to the following themes repeatedly during this
course
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Theme #1: Each discipline has its own concerns, its own set of
conceptualizations, its own set of assumptions, even when
they have a common focus (or at least overlapping foci)
Theme #2: Each discipline has its own set of ‘foundational
knowledge’.
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Moreover, each discipline has its own way of generating new
knowledge and its own way of deciding what ‘counts’ as new
knowledge and what does not (i.e., each discipline has its own
conception of the knowledges that are considered ‘legitimate’)
because we are engaged in a multidisciplinary pursuit, it is
important to understand these and be able to navigate these
when ‘moving between’ disciplines
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2. Social Roles, user and stakeholder
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User and Stakeholder
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When we use the term user and stakeholder, we may think
these terms refer to objectively-defined entities
However, these terms have certain assumpit is important ’
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Socially contructed
conception of the user (direct, indirect)
conception of a stakeholder, readings from Preece, Cooper
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the social roles of ‘user’ and ‘stakeholder’
conception of the user (direct, indirect), conception of a
stakeholder, readings from Preece, Cooper
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Roles and actors
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In sociology, social roles are conceptualized as a set of
connected behaviors, rights, obligations, beliefs, and
norms as conceptualized by people in a social situation
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basically, the part a person plays as a member of a social
group
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Roles are adopted or get assigned via different processes
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Roles are a way to theorize how society operates
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Roles are occupied by individuals, who are called actors
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The key point here is that we can recognize individuals,
and we can assign roles, but individuals are not roles and
roles and not individuals; they are not the same thing
Some Relevant Social Roles
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Designer, Programmer
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User
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Stakeholder
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Designer, Programmer
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Product Owner, Client
Designer
The behaviors, rights, obligations, beliefs, and norms that
are conceptualized to be connected with this role include:
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running the design process, makes key decisions about
process
having power, getting to decide
having expertise, having access to resources for the design
process (materials, funds, personnel)
(often) being an advocate for the user (but this desire can
compete with other objectives, such as meeting timeline
and budget targets)
being in a service role, serving the users’ needs
Users
We can define a user in a functional manner: if an
individual uses a system, then that makes them a user
However, the term user functions as a construct in
discourse about design, an imagined individual who is
potentially going to use a particular system
There are behaviors, rights, obligations, beliefs, and norms
that are ascribed to the role of user
Users: Two senses
There are two senses of user in the HCI literature (Cooper and
Bowers, 1995):
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the scientific sense: an object of study
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at one time, new and not-yet-understood
to understand users, various models have been proposed, such
as operator, cognitive agent, situated embodied actor*
the political sense: a constituency in need of empowerment
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strongly tied to liberal, humanist values of progress and
empowerment, tied to a rhetoric that praised technological
development for its power to transform society
connected to warnings that when users’ needs are not taken into
account, users will be left angry, scared, frustrated, etc
*we will return to the topic of user models
17
Users
in terms of users as an object of study, two sub-cases are
identified:
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primary users: frequent hands-on users of the system
secondary users: occasional users or those who use the
system through an intermediary
Prospective User
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what if a system does not yet exist and thus cannot yet
have users?
a role of 'prospective user' may be adopted by someone
who can 'stand in' for an actual user
sometimes the term 'user' is used as a shorthand for
'prospective user'
Stakeholders
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Stakeholders are “people or organizations who will be
affected by the system and who have a direct or indirect
influence on the system requirements” (Kotonya and
Sommerville, 1998).
…the group of stakeholders includes the development
team itself as well as its managers, the direct users and
their managers, recipients of the product's output, people
who may lose their jobs because of the introduction of the
new product, and so on (Sharp et al, 1999)
Product Owner
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a role, typically defined within Agile methodologies
the person responsible for maximizing the value of the
product being designer; empowered to make key
decisions
connected role: the client
It will frequently be the case that the formal ‘client’ who
orders the system falls very low on the list of those
affected…. (Dix et al, 2004)
3. Technology Acceptance vs Technology Use: A
disciplinary perspective
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Technology Acceptance vs Technology Use
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the concepts of technology acceptance vs technology use are
interesting to consider from a technosocial perspective
they both refer to similar phenomena, but approach the
conceptualization from different disciplinary perspectives
I am covering these two concepts in R-Design-I, in order to
leverage the material in that resource
However, I wanted to make this point here to provide an
example of theme #1 from earlier
•
Each discipline has its own concerns, its own set of
conceptualizations, its own set of assumptions, even when
they have a common focus (or at least overlapping foci)
23
User Interfaces
EECS 3461
Fall 2020
Resource R-Users-I
© Melanie Baljko
Dependencies
This module assumes that you are already familiar with:
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R-Interaction-I
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R-Technosocial-I and R-Technosocial-II
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R-Knowledge Practice-I
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R-Design-I
2
Topics
1.
How might we characterize human variation?
2.
User, system, and mixed initiative
3.
Models and metaphors for users
4.
The user model: users as ‘processors with operating
characteristics’
5.
The user model: users as information processors
6.
Norman’s gulfs of execution and evaluation
3
1. How might we characterize human variation?
4
Usability and Uniformity?
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in an earlier resource, R-Design-I, we discussed various
attributes of usability, such as effectiveness, efficiency,
utility, safety, learnability, memorability
we considered these attributes with some idea of the
human user in mind…
but we understand that:
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not everyone has the same goals
not everyone has the same resources to perform tasks
(physical and non-physical) - what counts as efficient for one
person will not necessarily be efficient for another
not everyone learns in the same way – what is easy to learn
for one will not necessarily be easy for another
not everyone remembers in the same way – what is easy to
remember (or to be reminded) for one will not necessarily be
easy for another
5
Thought question
I previously posed a few ‘thought’ questions.
When we read and understood the descriptions of each of
the different usability attributes:
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who did we have in mind when we envisioned the user?
what position of identity did we imagine for this
envisioned user?
what assumptions might we have made about the
envisioned user, even unwittingly?
what types of users are ‘centered’ when thinking about
interactive systems?
6
Characterizing Human Variation
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we understand that usability and other outcomes of
interactive system use (such as user experience) are very
much dependent on the particular individual
so it is very important to have some framework for
thinking and reasoning about human variation
I think it is very important to do so without resorting to
constructs such as ‘normal’ or ‘disabled’
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these constructs are problematic in ways we will discuss
over the course
7
A Starting Place
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there are many frameworks for thinking and reasoning
about human variation
we will start with the WHO’s ICD
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A Classification from the WHO
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The World Health Organization (WHO) publishes the
International Classification of Functioning, Disability and
Health (ICF), now in its 10th revision (starting in 2001)
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There is also a child and youth version (ICF-CY) which captures
aspects of functioning that relate to development
Provides information for broad purposes
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mostly basic public health purposes, but also for other purposes
such as management of social services and design of social
interventions
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makes it possible to collect data in a way that is consistent and
internationally comparable
the ‘internationally comparable’ attribute makes ICD attractive
as a starting place for us now
International Classification of Functioning,
Disability and Health (ICF)
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Body Functions are physiological functions of body systems (including
psychological functions).
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Body Structures are anatomical parts of the body such as organs, limbs
and their components.
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Impairments are problems in body function or structure such as a
significant deviation or loss.
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Activity is the execution of a task or action by an individual.
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Participation is involvement in a life situation.
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Activity Limitations are difficulties an individual may have in executing
activities.
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Participation Restrictions are problems an individual may experience in
involvement in life situations.
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Environmental Factors make up the physical, social and attitudinal
environment in which people live and conduct their lives.
Functioning
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The ICF does not use the term functional impairment, but rather
just the term functioning (as a noun)
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A person's functioning in seen neutrally and encompass all of
that individual's body functions, activities and involvement in
life situations.
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A person’s functioning can be viewed from three levels:
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body or body part (biological),
the whole person (individual), and
the whole person in a social context (social)
Functioning, Decrements
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Decrement in functioning is similarly viewed from three levels:
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a decrement in functioning at the body or body part level
(biological) is termed an impairment
a decrement in functioning at the person level is an activity
limitation
a decrement in functioning at the societal level is a participation
restriction
The Biopsychosocial Model of Disability
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The ICD gives rise to the so-called ‘biopsychosocial’ model of
disability
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disability is not a deficiency or abnormality; it is a difference in
functioning
disability is perceived as neutral; being disabled is a neutral attribute
specific attributes of a disability may be viewed as negative by people
who deal with them (e.g. pain, fatigue, depression), even by the vast
majority of people who deal with these attributes.
however, the model holds that the determination of whether an attribute
is negative or not can and should be made only be by those living with
the attributes. [1]
In a later resource, we will revisit this; we will compare the
biopsychosocial model with other models of disability (the charity
model, the medical model, the social model, the power/relational
model)
• For now, it is enough to understand that disability is a social
construct (as opposed to an ‘objectively determined state of being),
for which many models have been proposed and are to this day
being debated
•
Technology Design and
the Biopsychosocial Model
•
Technology design that is predicated upon the biopsychosocial
model starts with the premise that disability is not a deficiency
or abnormality; it is a merely difference in functioning
•
Technology design needs to consider functioning at the
individual level (body and body part level)
•
Technology design needs to consider functioning at the activity
level (tasks and actions)
•
Technology design needs to consider functioning at the societal
level, where do tasks and actions connect to a person’s life
situation, which includes the the physical, social and
attitudinal environment in which people live and conduct
their lives.
Technology Design Considerations
the Biopsychosocial Model gives rise to these
considerations:
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starts with the premise that disability is not a deficiency or
abnormality; it is a merely difference in functioning
consider functioning at the individual level (body and
body part level)
consider functioning at the activity level (tasks and
actions)
consider functioning at the societal level, where tasks and
actions connect to a person’s life situation, which includes
the physical, social and attitudinal environment in which
people live and conduct their lives.
15
2. User, system, and mixed initiative
16
Push and Pull
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Consider a client-server model
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pull: the initial request for data originates from the client,
and then is responded to by the server
push: the server pushes data to clients
push and pull requests illustrate a difference in initiative,
which entity is making the request?
17
Interactive Systems
Often, when we think of the configuration of user(s) and a
digital interactive system:
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We assume the user performs actions, and the system waits
for and responds to such actions
in this case, the user takes the initiative
But the converse can and does happen
•
the system originates the performance of an action on its
own
What triggers the action? can be accomplished via various
techniques, such as stochastic processes or time-based state
machine
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In this case, the system takes the initiative
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And a mixture of user and system initiative is also
possible
18
Examples of System-Initiative in Interactive
Systems
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Netflix pauses a person’s viewing to ask them whether
they would like to continue watching
A fitness tracker generates a notification to the user that
they having reached 10,000 steps during the day (or any
other type of milestone they have reached for a given
activity)
Google Lens automatically pops up information relevant
to a photo just taken (e.g., after taking a picture of a dog,
the pop up provides information on the breed of the dog)
19
Why are you telling me about initiative?
•
We will revisit the issue of initiative later…
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You can anticipate that there are many issues with system
initiative. We will discuss these later…
In various enumerations of different types of interaction,
initiative is typically a dimension of difference
20
3. Models and metaphors for users
21
User Metaphors
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we use metaphors as abstractions; they shift and evolve
over time
many different metaphors for human functioning have
been used over time:
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hydraulic metaphors (4 humors, keeping balance, reservoirs)
mechanical metaphors (clocks, steam engine)
metaphors of electricity and circuitry (chemical processes
generate action potential, galvonometer to measure electrical
current in biological specimens)
metaphors of telegraphy and the telephone (telephone
network)
information processor: computing, symbolic manipulation,
algorithms/function
metaphor shift tends to accompany major paradigm shifts
22
4. The user model: users as ‘processors with operating
characteristics’
23
Users as Operators
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[Grudin, 2012]
a model of users based on the idea of an operator from
ergonomics
from the early days of computing, in which computing
projects employed three roles: managers, programmers,
and operators.
•
•
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managers: oversaw design, development, and operation,
specified the programs to be written and distributed the
output
programmers: scientists and engineers, working with
mathematically adept programmers who decomposed tasks
into components that a computer could manage.
operators: ‘load’ the program by setting switches,
positioning dials, and connecting cables, then later cards and
tape; wait for program to finish; then take output (printout,
punched output, tape output) and put in distribution bins
24
Users as Operators
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•
[Grudin, 2012]
the interface consisted of the teletype, which was a kind of
very expensive command-line interface (CLI) (~$50K in
today’s dollars)
in this design domain, the goal of design was to improve
the design of buttons, switches, and displays to improve
operator performance through greater efficiency, fewer
errors, and better training
25
First Paradigm
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The early days of computing (e.g., 1965-1980, prior to
personal computing) saw interaction as a form of manmachine coupling
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[Harrison, 2007]
an amalgam of engineering and human factors, inspired by
industrial engineering and ergonomics
questions to be answered: what are the problems in the
coupling? how can we developing pragmatic solutions to
them?
goal of design:
•
optimize the fit between humans and machines, deal with
the concrete problems that arise in interaction and that cause
disruption
26
Model Human Processor (Card et al, 1983)
•
•
•
•
One of the first HCI models to be used; based on
information processing model
Models the information processes of a user interacting
with a computer
Predicts which cognitive processes are involved when a
user interacts with a computer
Enables calculations to be made of how long a user will
take to carry out a task
27
5. The user model: users as information processors
28
Second Paradigm
•
Next comes a revolution that that human minds are like
information processors, and that interaction can be modeled
as information exchange between humans and computers
•
•
the paradigm places “rationality and rational analysis [as] the
most important mode of operation for human activity”
(Flyvbjerg, 2001, p. 23)
questions to be answered:
•
•
[Harrison, 2012]
‘how does information get in’, ‘what transformations does it
undergo’, ‘how does it go out again,’ ‘how can it be
communicated efficiently’
premise:
•
•
human information processing is deeply analogous to
computational signal processing
the primary interaction task is enabling communication between
the machine and the person
29
Second Paradigm
•
[Harrison, 2012]
premise and starting assumptions:
•
•
•
•
human information processing is deeply analogous to
computational signal processing
the primary interaction task is enabling communication
between the machine and the person
operations performed by one in pursuit of a goal affect the
state of the other
If we modeling the state of the person as well as of the
computer, then we can predict and optimize the relationship.
30
Human as an Information Processor
•
•
•
a framework that explains how people think/do
it uses metaphor of an (digital) information processor for
the brain (and thus for cognition)
the metaphor abstracts away the human body, the
interactant is reduced to a brain
31
Information processing
•
Conceptualizes human performance in metaphorical terms
of information processing stages
www.id-book.com
32
What happens in the middle?
•
In this model of the user:
•
•
•
•
there is an input stage
there is an output stage
In between receiving the input and producing the output,
something is happening in the mind of the user
what is happening? this middle part is the cognitive
processing
33
34
Mental Models
•
a framework that posits that people use mental models
generally in cognition, for:
•
•
•
•
•
There are two key points
•
•
•
reasoning, making decisions
generating their next actions
generating explanations about what they observed
… many more
a mental model is an internal construction
a mental model can be "run"
There is plenty of evidence that people have mental
models
35
Mental models: How do they work?
•
Craik (1943) described mental models as:
•
•
•
•
internal constructions of some aspect of the external world
constructions that are manipulated somehow (processing)
this result of the processing is that predictions and inferences
can be made
Johnson-Laird (1983) and others
•
•
•
•
the process involves unconscious and conscious processes
the process involves 'fleshing out' the mental model
the process involves 'running' the mental model
the process involves activation of images and analogies
36
Deep vs Shallow Mental models
•
Mental models can be formed in a deep or a shallow way
•
Example of a deep model:
•
•
•
•
•
•
Example of a shallow model:
•
•
•
•
•
•
a model of how a car operates to the extent that you can trouble-shoot
how the combustion engine turns over, alternator, etc
how fuel lines/carberator/etc work
how braking systems operate
how steering systems operate
a model of how a car operates to the extent that you can drive it
how to start the car
how to accelerate
how to brake
how to turn
to drive, a shallow model suffices; to trouble-shoot malfunction,
need a deeper model
37
How Do Mental Models Develop?
•
•
Users develop an understanding of a system through
learning about and using it
Knowledge is sometimes described as a mental model:
•
•
•
How to use the system (what to do next)
What to do with unfamiliar systems or unexpected situations
(how the system works)
People make inferences using mental models of how to
carry out tasks
•
•
•
•
they may start with incorrect assumptions
they may use inappropriate analogies
they may bring superstition into the process
they may use evidence to revise their mental models
(towards or away from the correct model)
38
Shallow and Incorrect Mental Models
•
•
there is plenty of evidence that the mental models are
frequently erroneous
Examples: thermostats, household plumbing, tailgating,
elevator and crosswalk buttons, etc etc
39
6. Norman’s gulfs of execution and evaluation
40
Gulf Bridging
•
•
not really a separate framework from mental models;
rather an further component to explain how people
behave
the framework supposes there are two gulfs:
•
•
a gulf of execution
a gulf of evaluation
41
Bridging the gulfs
42
Gulf of Execution
•
the gulf of execution is the difference between the
following two things:
•
•
•
the user’s model of what system is (and what the possible
next actions are)
what is actually possible with the system
each user will have their own version of this gulf
43
Gulf of Evaluation
•
the gulf of evaluation is the difference between the
following two things:
•
•
•
the user’s model of the system state (what just happened,
given action I just did?)
the system’s actual state
each user will have their own version of this gulf
44
Application of the Gulfs
•
Norman’s model of the gulfs of evaluation and execution
have been applied to the design process (which we will
cover in R-Design-II)
45
User Interfaces
EECS 3461
Fall 2020
Resource 01-A, Core Constructs in Interaction I
© Melanie Baljko
What is User Interaction?
User interaction refers to the potential and expressed human
behaviours that arise in connection with interactive systems
within socialtechnical systems*
•
•
these behaviours can encompass many different aspects of
use and experience
these behaviours can occur at different points in time:
•
in anticipation of interaction
•
during interaction
•
as a result of interaction
*there are many definitions in the discipline; this is the definition that will be used in
this course
What is an Interactive System?
An interactive system is a computational system that affords
interactivity to human users *
A computational system is a digital computer consisting of
software and hardware components**
•
this seemingly simple definition has several important
terms: afford, and interactivity
*there are many definitions in the discipline; this is the definition that will
be used in this course
**this could be generalized to any digital, analog or hybrid physical
artefact that is capable of performing computation
3
The Micro, Meso, and Macro Levels
In user interaction, we can model interaction at the micro,
meso, and macro levels:
•
micro-level: interaction between an individual and a
particular computational interactive system
•
•
meso-level: interaction phenomena at the ‘group’ level
•
•
e.g., how fast a given person can acquire a target using a
mouse pointing device
e.g., among “youth in Canada” or ”the reddit community
macro-level: interaction phenomena at the large group
level
•
e.g., technology adoption within an economic system,
technology use as part of citizenship (such as on-line voting
or broadband Internet access)
4
What is a Sociotechnical System?
A sociotechnical system is an interlinked mixture of people,
technology, and their environment.
•
•
“A sociotechnical system … is the term usually given to any
instantiation of socio and technical elements engaged in goal
directed behaviour.” (p.112, Asai, 2008, Human Computer
Interaction: New Developments)
technology here refers not only to computational systems or
other material technologies, but more generally on any
physical or conceptual purpose-driven assembly
In many sociotechnical systems, interactive computational
systems figure prominently
A sociotechnical systems approach allows us to consider
the micro, meso and macro-level phenomena in a unified
framework
5
Take Note
Looking at user interaction using a sociotechnical systems
perspective is one particular perspective.
Another perspective (which was at one point the dominant
perspective) is the cybernetic system view.
These views can stand in tension. And the heritage of the
older view that is based in cybernetic systems is still all
around us. We’ll come back to this…
6
A Systems-Level View of Interaction
A systems framework can be used as the basis for modelling
user interaction.
Systems are the subjects of study in systems theory.
A system is a "set of elements standing in interaction” (p.
38, von Bertalanffy, 1968).
7
User Interaction at the Micro Level
So given that a system is set of elements standing in
interaction, then to model user interaction at the micro
level, we need to model the two elements:
•
‘human’
•
‘interactive computational system’.
We want to position these elements in interaction with one
another.
And we need to theorize about how these elements interact
with one another.
For this, we will now talk about the concepts of ‘input’ and
‘output’.
8
Input and Output
The field of robotics makes use of the constructs of sensors
and actuators.
The fields of automation and control theory make use of the
constructs of input device and output device.
The field of human psychology makes use of the constructs
of sensation and perception (input), and motor control
(output).
Sensors and articulators are constructs we can use to
characterize computational interactive systems.
9
Sensors
Sensors in robotics are based on the functions of human
sensation.
Notice the use of analogy from humans to robots.
Analogies can be very useful. Analogies can also create
implications. We will revisit this point throughout the
term, since this is a core issue in the fields of UI/UX and
HCI.
10
Sensors are not Senses
Don’t confuse a human sensory pathway with a human sense. The
pathway is only part of the sense.
Example
1.
a human sensory pathway is the eye’s photoreceptors,
combined with particular neural pathways, which then
reach certain brain regions.
2.
a human sense is vision, which uses that pathway
•
•
In the pathway, when light hits the eye, the photoreceptors
produce a response that travels along neural pathways and
results in brain activity.
In vision, there is a ‘feedback loop’. Vision is not passive and
does not consist only of ’input processing’. The visual system
also involves action as well
•
for instance, the brain causes action of the eyes in order to scan
the visual field in response to visual stimuli
11
Sensors of Interactive Systems
The sensors of computational interactive systems are the
‘components’ which are capable of receiving input.
•
Input devices (like keyboards, mice and other pointing
devices) all have sensors.
•
•
•
The era of traditional personal desktop computing served to
solidly establish the concept of an input device.
Now that computing has moved off the desktop, many
interactive systems shifted away from conventional input
devices.
‘Sensor’ serves as a more basic construct than input device.
Sensor examples: goniometric sensors, photosensors, proximity
sensors, touch sensors (e.g., consider all the different sensors that can
be connected to a Raspberry Pi).
12
Sensors and Transducers: Being Very Precise
If we wanted to be very precise, we should really
distinguish between sensors and transducers.
Sensors sense the physical changes that occur in the
surrounding, whereas transducers converts the signal from
one physical quantity or nonelectrical into another signal or
electrical signal.
But we don’t need to be this precise. The main point is that
computational interactive systems receive input and we use
the concept of a sensor to conceptualize this.
13
Actuators and Articulators
The field of speech science uses the construct of speech
articulators, which are the parts of the body involved in the
production of speech (e.g., the lips, tongue, vocal folds,
lungs, among others body parts). Speech production is a
specialized part of motor control.
The field of robotics makes use of the construct of actuators,
which are machine component that are responsible for
movement and control.
14
Articulators of Computational Interactive
Systems
The sensors of computational interactive systems are the
components which serve to produce output.
In the era of traditional personal desktop computing, the
articulators corresponded to the output devices: the display
monitor and speakers.
Computational interactive systems make use of many other
types of articulators now. There are plenty of systems that
have interfaces mostly based in audio*
*e.g., they do not make use of any type of screen and have limited, if any,
visual displays, such as indicator lights
15
Humans and the Articulation of Actions
Humans have many ways to effect actions upon the world that can
form the basis for computational system interaction
•
The human motor system
•
•
used to perform actions in the world (speaking, pressing, typing, hand
movement, etc)
Edge cases:
•
Locked-in syndrome
a rare neurological disorder in which there is complete paralysis of
all voluntary muscles except for the ones that control the
movements of the eyes
• Specialized interfaces can track eye movements and interpret as
different system actions
Total locked-in syndrome
• a version of locked-in syndrome wherein the eyes are paralyzed as
well other systems for effecting action upon the world
•
•
•
Specialized Brain-Computer Interfaces (BCIs) can detect
intentional thought and can interpret into different system actions
16
System Elements: Inputs and Outputs
•
Computational interactive systems:
•
•
•
•
Have articulators and sensors
Have ‘inner state’ (as determined via computational
processes)
Are hardware-software systems
Human users:
•
•
•
Have bodies with sensory-perceptual pathways
Have bodies with motor systems (and other systems for
effecting action upon the world)
Are biological systems
17
The Cybernetic Loop
•
•
•
Next we will be introduced (briefly) to the model of the
cybernetic loop
We will return to the model of the cybernetic loop later in
the course
The point of this next slide is to acknowledge this model
exists and to flag it for further discussion and critique
18
The Cybernetic Loop
Cybernetics is "the scientific study of control and
communication in the animal and the machine” (Wiener,
1948).
Starting in the 1970’s, user interaction was viewed as a
specific type of cybernetic loop, where the interactive
computer is viewed as a ‘feedback machine’ and the user is
the ‘controller’.
19
Affordances
•
•
now we will transition to the concept of affordances
this concept is important since it is foundational to our
definition of interactive systems
•
a computational system that affords interactivity to human
users
20
What is an affordance?
•
The concept of affordance is often misunderstood and
misused in UI/UX
Gibson
•
Gibson [1977], a researcher in the field of psychology,
originally defined the term affordance as follows:
Affordances are all "action possibilities" latent in the
environment, objectively measurable and independent of the
individual's ability to recognize them
James J. Gibson (1977), The Theory of Affordances. In
Perceiving, Acting, and Knowing, edited by Robert Shaw and
John Bransford, ISBN 0-470-99014-7.
22
Gibson’s concept
•
Gibson’s concept of an affordance implies a separation of
performability and perception
•
performability: whether or not a feature of the environment
provides an "action possibility" to a particular individual
depends on the individual’s embodiment
•
this, performability is about the relationship of the
environment and the individual
I will provide examples shortly
perception: whether the individual has the ability to
recognize the action possibility or not does not matter to the
the concept; even in the absence of perception, the action
possibility remains
•
•
23
The Design of Everyday Things,
Norman (2002)
•
In 2002, Norman took Gibson’s concept of an affordance
and applied it to the practice of design:
“the term affordance refers to the perceived and actual
properties of the thing, primarily those fundamental
properties that determine just how the thing could possibly be
used” (p. 9, 2002)
Norman, D. A. (2002). The design of everyday things. New
York: Basic Books. ISBN 0-465-06710-7.
•
While this restatement is not incorrect, it is written in a
way that lead to many misunderstandings…
Mass Misuse of the Concept of Affordance
•
•
Norman’s book became hugely popular
Many practitioners took up the term ‘affordance’ but
misused and misunderstood the concept for the next
decade
•
•
•
instead of focusing on performability, the focus shifted to
perception
In all fairness, this seems likely since Norman could have
been more careful in retrospect
Here is an example of the misuse
•
Preece (2002): affordance “is a term used to refer to an
attribute of an object that allows people to know how to
use it”
25
The Design of Everyday Things, 2nd Ed
Norman (2013)
•
In 2013, Norman noted:
•
•
•
•
•
the term affordance “created much confusion in the world of
design”
"… the term became used in ways that had nothing to do
with the original"
"Many people find affordances difficult to understand
because they are relationships, not properties."
"Designers deal with fixed properties, so there is a
temptation to say that the property is an affordance”
In the second edition, he worked on correcting the misuse
and clarifying
Ongoing misuse…
•
•
Despite Norman’s efforts to correct the misuse of the term
affordance, the misuse continues
E.g. Preece (p. 30, 2019), still has in the section
“Affordance” “This is a term used to refer to an attribute of
an object that allows people to know how to use it.”
27
Analysis
•
•
Take this statement: an affordance is a term “used to refer
to an attribute of an object that allows people to know how
to use it.”
Why is this incorrect?
•
•
•
The concept of an affordance captures the relationship
between a ‘thing that can be used’ and ‘the user’ (the one
doing the perceiving)
The concept of an affordance does not refer to a property of
an object.
See the next examples which illustrate…
28
Door Example (I)
•
•
•
Say a door has a pull handle (and it is positioned at the
chest level of a person of average height)
Person A approaches on foot and perceives the pull handle
visually. The person knows that pulling on the pull
handle will cause the door to swing on its hinges towards
them (knowledge).
The handle affords pulling for person A.
•
•
•
•
Opening the door is an action possibility for person A.
The door affords ‘pullability’ for person A.
The possibility was latent in the environment (for Person A),
independent of Person A’s ability to recognize it.
Perception of the possibility was visual, likely as the door designer
envisioned
29
Door Example (II)
•
•
•
Say a door has a pull handle (and it is positioned at the
chest level of a person of average height)
Person B has a visual impairment and is not able to see the
handle. However, they reach out and feel the handle and
then pull on it.
The handle affords pulling for person B.
•
•
•
•
Opening the door is an action possibility for this person B.
The door affords ‘pullability’ for person B.
The possibility was latent in the environment (for Person B),
independent of Person B’s ability to recognize it.
Perception of the possibility need not be visual and can be any
manner of perception or discovery, even if the door designer did not
anticipate it
30
Door Example (III)
•
•
•
Say a door has a pull handle (and it is positioned at the
chest level of a person of average height)
Person C uses a wheel chair and approaches the door.
They perceive the pull handle visually. They reach up but
cannot reach it because it is too high. And even it they
could reach it, the door is heavy and they can’t move their
chair back while simultaneously pulling.
The handle does not afford pulling for person C.
•
•
•
•
Opening the door is not an action possibility for person C.
The door does not afford ‘pullability’ for person C.
The possibility was not latent in the environment (for Person
C), irrespective of Person C’s ability to recognize it.
Activation of the action possibility will often be contingent on
certain capabilities; designers often make implicit assumptions
about the required capabilities
31
Door Example (IV)
•
•
•
Say a door has a pull handle (and it is positioned at the
chest level of a person of average height)
Person D has a visual impairment and is not able to see
the handle. However, they reach out and, despite feeling
for the handle, do not locate it. They turn around and
leave the doorway.
The handle affords pulling for person D.
•
•
•
•
Opening the door is an action possibility for this person D.
The door affords ‘pullability’ for person D.
The possibility was latent in the environment (for Person D),
even though Person D did not recognize nor make use of the
possibility.
Perception of the possibility need not be visual and can be any
manner of perception or discovery. The designer can provision for
this by providing cues and signals that are not likely to be missed.
32
Interactivity vs Reactivity
•
Would you call this light switch an interactive system?
33
Reactivity…
•
•
reactivity is the quality or condition of an entity of
being capable of reaction
Examples:
•
•
•
for a given stimulus, there is a response
for a given input, there is an output
There is a direct mapping from input to output (or from
stimulus to response)
•
•
•
The mapping is simple, the response is completely
determinable from the input
No notion of memory or history or inner/internal state
e.g., a light switch is reactive, pupil dilation response to
bright lights
The Light Switch Affords Reactivity not
Interactivity
•
This light switch affords reactivity to its user.
•
The lights are completely controlled by the user
35
Conversation as a Paradigm of Interaction
“The important features of … interaction with another person
can be thrown in relief by comparison with pathological
cases.”
•
•
“If someone refuses to respond to our questions and spits out
one non sequitur after an other, then we would not say that we
were interacting with that person.”
“On the opposite end of the spectrum, if a person only repeats
our questions, translates our speech into another language, or
barks once for each syllable we utter, then, again, we would not
say that a successful interaction takes place.”
“These two pathological poles of human conversation indicate
that neither random reactions nor predictability bordering on
limited control are characteristic of interactivity; rather, it must
be that a certain kind of responsiveness absent of control and
predictability is necessary for there to be interaction.”
Smuts, The Journal of Aesthetic Education Vol. 43, No. 4 (WINTER 2009), pp. 53-73
36
Mutual Responsiveness
These contrasting examples excerpted from: Smuts, The
Journal of Aesthetic Education Vol. 43, No. 4 (WINTER 2009),
pp. 53-73
Consider
(i) falling rocks from a cliff
Vs
(ii) dodging firecrackers
37
(i) Cliff Example
Suppose you are standing at the bottom of
a cliff and rocks are randomly falling
down.
You might move back and forth to dodge
the rocks. But the cliff does not respond to
anyone's position below and adjust the
falling rocks to her position. You and the
cliff are not interacting with one another.
This example illustrates that one can
repeatedly respond to something without
interacting with it.
The cliff does completely control.
38
(ii) Firecrackers
“If I am dodging firecrackers thrown by my cousin, who is
aiming at me, then I am interacting with my cousin.”
39
Mutual Responsiveness
“If cannot interact with falling rocks but we can with a
sadistic cousin, then can safely say that interactivity
requires some kind of mutual responsiveness. Accordingly,
we can say that for something to be interactive it must able
to respond in a particular way”
40
For a computational system to afford
interactivity…
Something is interactive if and only if it
1.
2.
3.
4.
is responsive,
does not completely control,
is not completely controlled, and
does not respond in a completely random fashion.
Smuts, The Journal of Aesthetic Education Vol. 43, No. 4 (WINTER
2009), pp. 53-73
Thus, this definition shows that interactivity
needs to be characterized carefully.
Summary
•
•
•
•
The sociotechnical systems approach focuses on the
interaction between people and technology
In these systems, humans and computational interactive
systems are the elements that stand in interaction with one
another
Each of these elements (humans, computational interactive
systems) are theorized in terms of their respective means
of receiving input and producing output
Interactivity is different from reactivity. Interactivity is
characterized carefully
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