C.7 Ease of Use
Bonnie E. John, Raj Reddy and Rod Smith
Ruzena Bajcsy, Doyle Baker, Sara Bly, Anita Borg, Bill Buzbee, Elizabeth
Coppinger, Michael Deering, James Farber, Joel Frendt, Kevin Lacobie, Robert
Logan, David Marques, James H. Morris, Steve Oberlin, Eldon Patterson, William
A. Rowe, David R. Schwartz, Neil Scott and Alan Tannenbaum
The success of the National Information Infrastructure ultimately depends on it
being usable by real people. If access to information and communications-based
services is to be effective and universally available, the user interface to
the network and its services must be easy and fun to use. Simply providing
bandwidth and connectivity, which has served the scientific community well,
will not be sufficient for the NII without ensuring that services are
accessible and usable by people without computer training.
Examples of the importance of the user interface to the success of
communications and information systems are easy to find. For example:
- A major factor in the success of the basic telephone system is its simple
and ubiquitous user interface. Even a child can dial or answer a call--anywhere
in the world.
- The usability and attractiveness of graphical, windowed computer
interfaces are largely responsible for the recent explosion in the use of
personal computer software by professionals and their families.
- By providing an interface that is easy to learn and use, Mosaic is opening
the Internet to a much broader audience than ever before.
2. The Technical Challenges of Universal Access
The theme of universal access interfaces focuses on the notion that all users
without exception should have availability to NII services. This concept has
three prongs: affordability, ubiquity and usability. The lack of any one of
these can represent an impediment for potential NII users. The human-computer
design principles for universal access interfaces should be clearly defined as:
The approach for achieving universal access interfaces should be to focus on
research issues that are at the intersection of NII needs and general
- Not all users have the same economic resources. The interface must provide
adequate access to information on inexpensive devices.
- Not all users have the same cognitive and physical capabilities. The
interface must provide all users with equivalent access to information despite
these differences. Additionally, the interface must address the differences in
the levels of skill and experience of various users.
- Not all equipment is equal in function. Different equipment requires
different interaction paradigms--i.e. set-top boxes for interactive TV,
personal computers, telephones, kiosks, personal digital assistants, etc. The
interface should meet the needs of various classes of users and should not be
forced to some lower common denominator.
- An NII user interface must automatically adapt to the characteristics of
the connection--e.g., different physical interface connections, resolutions and
- The network must support the connection of a variety of access devices
meeting the wide-ranging needs of the entire population.
- Although a wide variety of interfaces must be supported, users should not
have to wait until all have access in order for some to have access. Careful
balance is needed between the conflicting goals of universal availability and
3. Research and Development Recommendations
Ensuring that the NII will be usable by the widest possible audience requires
an explicit program of research, standards and development that focuses on
three critical elements:
This section provides key findings and recommendations for a research agenda in
each of the above areas.
- Understanding user needs at the individual, organizational and
- Identifying and promoting technologies critical to ease of use.
- Establishing processes and metrics to guide the development of usable
3.1 Findings and Recommendations: Individual, Social and Cultural Aspects
Developing an in-depth understanding of the individual, social and cultural
aspects of NII users will be one of the most important first steps of the
ease-of-use research. The wealth of knowledge developed initially by studying
the areas of education, health and electronic commerce can set the groundwork
for evolving NII services and applications to reach a broader audience over
time. The issues include understanding the user on individual, organizational
and sociocultural levels; and understanding tasks, environments and multiuser
3.1.1 Understanding Users
Americans are extremely diverse. To achieve universal accessibility of the NII,
the differences and similarities between individuals and groups must be
understood. This research can be broken into multiple research areas:
1) "Walk-up-and-learn" interfaces will be the predominant force for
universal access. Understanding how individuals can use their previous
real-world knowledge to navigate through the NII and use its applications is
the purview of psychological research. Although there is much existing research
in psychology that can be of use, additional support is needed to put that
knowledge into a form that developers of the NII can use to design their
2) NII interfaces must "evolve gracefully." That is, consumers must be
allowed a step approach to access the NII with increasing power and
sophistication as their familiarity, needs and equipment evolve without
relearning a core set of skills. This is sometimes called "research in
3) The cultural context of the NII must be explored. Basic research on
broadly defined aspects of American life is needed to identify opportunities
that could improve quality of life both at work and at home. Analysis of
current trends can point to new product and service categories. Broad domains
of trend research should include entertainment, communications, work and
travel. In addition, the existence of the NII itself will create new social
systems in the United States that will have their own emerging needs. Sample
- Electronic mail as a new human-to-human communication medium, no less
significant for culture than writing or the telephone. Understanding this new
medium is essential in helping to anticipate and design new solutions.
- Electronic forums and electronic town halls and their future role in the
democratic process. What is the viability of such tools in the democratic
process and how it is implemented?
- Evaluation of music videos and video games to understand their
applicability to the education process. The intrinsic lure of entertainment to
youth offers an opportunity for students to author their own intellectual
- Evaluation of the growing virtual office and telecommuting trends. These
early adopters of NII-type technologies represent the cutting edge of a
cultural change in society.
- Finally, pre-competitive research on sociocultural trends is required
given that this is not a typically profitable area for the private sector to
invest in and given the need to ensure that these findings are publicly
available and not held as proprietary information.
3.1.2 Understanding User Tasks
Rigorous investigation of existing and anticipated tasks associated with the
NII is required to fully identify the scope of user requirements. Task models
are the basis for all product design and the NII should be no different.
3.1.3 Understanding Environments
Users and technology cannot be considered in isolation. Rather, both exist in
the context of environments. Traditional environments such as offices,
hospitals and schools have received some investigation, but more is required
with the onslaught of enabling technologies. Additional understanding of less
traditional environments such as inner-city public access terminals,
transportation and recreational users is also required.
3.1.4 Understanding Multiuser Collaboration
Much work and play is accomplished in the context of social activity; rarely
are tasks done in isolation. The NII offers access not only to extensive
sources of information but to varied and far-flung interactions. Users will
have the ability to connect to friends, colleagues and experts who previously
would have been accessible at best by phone or mail. The NII capabilities
further such interactions by erasing the boundaries of space and time. We list
four research topics here:
1) Much of the work and entertainment is social. Current single-user models
of computer and networked use cannot meet such a need. Research is needed to
understand the workplace's social context in order to bring this context into
network/computer-mediated work. For example, medical providers need to have ad
hoc "hallway" conversations with their remote colleagues just as easily as they
now do with their colleagues in the same building. Electronic mail and
telephony are not rich enough to provide sufficient social context for these ad
2) As networked (NII-mediated) collaboration becomes more common, community
access, privacy and community control become areas needing significant
research. For example, medical patients depend on privacy, yet need to be able
to find similar case studies and share information with support groups.
Research is needed on access models for collaboration that can meet these
diverse and often conflicting needs.
3) Through the NII, most users will participate in many different
"communities," both geographically local ones and geographically dispersed
communities. Research is needed on how users will do that, how they will
socialize in the new networked communities, how different access rights will
exist across communities and how users will "code switch" between them in the
same sense that multilinguals code switch between communities. This has very
strong user interface implications that are not well understood at present.
4) There are a variety of technical research issues such as different
levels of interaction needed and desired for different tasks and different
3.2 Findings and Recommendations: Technologies
Many proposed uses for the NII cannot be successfully implemented today.
Barriers include limitations of device performance, a high cost threshold and a
lack of interface software. Development of enabling technologies would expand
interaction via the NII at all levels (from lowest cost to the highest
Development examples where stimulus is required include:
Other needed hardware items will be developed naturally in response to the
economic stimulus created by the NII (bright projection displays, distributed
storage, low data capacity backchannel, microphones).
- Remote expert image analysis applications (e.g., medical) require
currently unavailable display performance--higher resolution, higher fidelity,
and color and monochrome displays of high visual quality, free of the
quite-visible annoying artifacts.
- Mobil access to the NII will require thin, high-resolution, low-power,
lightweight portable displays. The ability to view three-dimensional images
requires that the NII include three-dimensional graphical user interface
standards, hardware and software.
- The general population has little computer literacy and will adopt the NII
faster and in greater numbers if natural and more familiar I/O devices and
interfaces are available (i.e., pen, speech, joystick and touchpad, either
singly or concurrently).
- Mass adoption of the NII demands low-cost NII interfaces that use the TV
as the display device.
3.2.2 Adaptive Intelligent Interfaces
Given the scope and magnitude of the NII, new approaches to end-user interfaces
and their construction will be necessary. For example, in the medical field,
new user interfaces that continually learn and remember information regarding
specific areas of medicine will be essential to keep up with the information
dynamics of recently published research and studies. Additionally, these types
of interfaces will "learn" a person's viewpoint or interest to build
self-describing search criteria.
These interfaces will be characterized by:
Toward this end, a significant effort must be undertaken to create intelligent,
adaptive computer-based systems that integrate seamlessly into the human use of
the NII, including the technology base that enables systems developers to
rapidly create and deploy systems that exhibit intelligent behavior.
- Their ability to adapt to users' unique needs and skills. This includes
such things as recognizing capabilities and limitations of the user's current
context, including hardware, and adjusting the interface accordingly.
- Their ability to know what they do not know, engage in a dialogue with the
user about that knowledge gap and learn from that dialogue for future use.
- Their ability to learn about users, their tasks and the NII through
diverse means appropriate for different situations. For example, learning from
deliberate instruction or demonstration by the user, through exploration or
through passive observation of user behavior. Systems with several learning
strategies must also be able to reason about the appropriateness of those
strategies to particular situations.
- Their ability to intelligently filter information so individual users can
choose to limit access to specific types of information (e.g., filters that
recognize pornographic images, enabling parents to prohibit them from entering
- Being as easy to construct a suite of agents personalized to an NII user
as it is to build a playhouse with a child's interconnecting blocks.
3.2.3 Human-Centered Input Methods
Human-centered interfaces refer to natural human-machine interactions using
advanced input methods. The closer NII interfaces match real-world concepts,
the faster we will achieve acceptance of those services. Pen, speech and
natural language are viewed as the first of these input methods.
Pen (and touch) enables the paper-like interface so common in education,
authorization, forms and writing tasks. Speech has the potential to have a
completely hands-free modality that can be envisioned as the ultimate
interaction technique in the home and hands-free environments, as well as
enabling the NII for the disabled and citizens with varied education levels.
Together with natural-language comprehension and generation, these methods will
enable users to interact with services using person-to-person metaphors.
In the future, NII interfaces will need to automatically sense additional
physical information about the user, tracking the location and orientation of a
person's sense organs (eyes, ears, mouth, head), as well as their hands (for
gesture recognition) and potentially their whole body. This extends to sensing
the location of a person within a room, building or city.
In order to be successful, we must evolve the research in navigation,
recognition and semantic understanding technologies to the next stages of
handling unconstrained input. Human-like feedback technologies, including
natural voice response, anthropomorphic agents and intelligent dialogues
complete the package and need to be a key focus area. Natural-language
processing (NLP) is an important enabling technology for many of these
features, and research should be continued in this area for the NII.
The use of the pen, speech and other modalities simultaneously has the
potential of having a synergistic effect when applied to the communication of
ideas (e.g., voice-over-ink annotations) and the recognition of written or
spoken commands and data.
NII participants will be bombarded with services and data from a multitude of
sources. Our methods of presenting this information in digestible forms must be
enhanced. Advanced visual (two-dimensional and three-dimensional), auditory,
tactile and other sensory "views" can increase the user's ability to filter
this information and identify, extract and enhance its content. Also, advanced
techniques of cinematic direction enhance user interaction with anthropomorphic
Research is needed in:
- Navigating and sifting through abstract views of NII services that vary on
a variety of dimensions.
- Remotely analyzing and annotating (via voice, digital ink, etc.) medical
- Remotely interpreting multidimensional data residing in centrally located,
- Interacting with anthropomorphic agents that provide varied, useful and
natural views of themselves.
- Acting within virtual environments for entertainment purposes.
- Studies of how sensory dimensions (e.g., color, pitch, texture) can be
used to code information and how users relate such sensory dimensions to form
- Studies of multidimensional coding strategies that allow users to
effectively navigate within a large body of elements and to narrow their search
by successive filtering of these views.
- Studies of how modern cinematic techniques are used to broaden acceptance
of cinematic characters by an audience and how similar techniques could be
enabled for use with anthropomorphic entities.
By "authoring" we mean the creation and organization of the multimedia,
hypermedia, video and virtual environment information presentations that will
be made available on the NII.
Creating high-quality, effective multimedia/hypermedia for the NII, be it for
education, entertainment or information presentation, takes too much time
(sometimes as much as 1,000 hours for one hour of presentation) and requires
considerable expertise. This represents a "production bottleneck" for one of
the key commodities that will be distributed (and indeed created) with the
The speed issue can be addressed with research to develop metaphors and
approaches for authoring systems, with a goal of an order of magnitude decrease
in authoring time. The expertise issue can be addressed by developing authoring
tools that encourage and facilitate good design practice, by means such as
intelligent agent "design critics," including "codes of practice" in the tools
or in templates, style sheets or examples. One objective of this work should be
to empower every individual user of the NII to be an information creator.
Similarly, shared virtual environments (including the simulation of physical
processes that so often are an important part of these environments) need to be
much more easily created than they now are. Tool kits that minimize and in some
cases eliminate traditional programming are needed.
3.3 Findings and Recommendations: Metrics and Evaluation Techniques
The developers and consumers of NII software and hardware need to know how
effective the products and services offered will be in fulfilling their needs.
Consumers need to be able to make cost-benefit trade-offs for any particular
access mechanism (e.g., I/O device, software options for accessing the NII) or
application on the NII before they buy. The costs include usability issues like
learning time, organizational-fit and satisfaction, as well as direct monetary
costs. Developers need to understand the usability implications of their design
decisions to direct design effort.
To fulfill this need, research is necessary to define metrics and techniques
(observational, analytic and heuristic) for assessing individual usability,
group usability and how NII systems will fit into a social or organizational
context. An important step is to validate these metrics and evaluation
techniques by comparing their results to rigorous empirical tests of real
systems in real-world use. The definition and validation of metrics and
evaluation techniques are each themselves an iterative, continuous process
during the life of the NII.
Currently, the most well-defined metrics are for individual performance: time
to perform a task and time to learn to perform a task. Although these metrics
are important to a large segment of U.S. workers, they do not cover many other
aspects of NII uses such as:
1) Individual metrics:
2) Group metrics:
- Errors: Even the definition of "error" is ambiguous. Does an error occur
whenever someone deviates from the optimal procedure for performing a task or
only when someone behaves in a way that prevents the task from being
successfully accomplished at all? Are behaviors then the cause of frustration
errors? How do you consider quality in the error metric?
- User satisfaction: Some work has been done (e.g., University of Maryland's
Questionnaire for User Interaction Satisfaction), but additional validation and
extension to groups is needed.
- Quality of product: What constitutes quality? for individuals? for teams?
- Fatigue, boredom, etc.
In addition to the group analogs of the individual metrics, metrics
specific to groups and communities need to be developed and validated, e.g.,
level of cooperation or homogeneity of a group.
3.3.2 Evaluation Techniques
Evaluation should occur at many levels, for example:
Evaluation can reflect national priorities that industry will not do, e.g.,
does an entire school system meet its educational goals in a cost-effective way
using the NII, and if so, how?
- Individual components: e.g., Are high-resolution, cost-effective displays
readable for some benchmark texts and graphics?
- Integrated applications: e.g., How effective is combining pen with speech
for a data acquisition task?
- Use in context: e.g., Does use of the NII make a public school teacher
more effective in teaching a particular curriculum, and if so, how?
Three types of evaluation techniques have arisen from human factors and
human-computer interaction (HCI) research: observational, theory-based and
heuristic. Currently, observational techniques--i.e., watching users as they
use an application--are dominant in the computer applications industry and will
undoubtedly continue to be useful in the development of the NII. In fact, the
NII poses the opportunity for forums where users of applications directly share
product experience and potential users can judge whether they wish to invest
both time and money in a particular application. However, the NII also poses
unique problems for evaluation. In particular, when applications move from
being a single-user in front of a workstation to groups of users geographically
and temporally distributed, observational methods are not easily used. Due to
this and other drawbacks of the observational approach, the NII requires
research into other methods of evaluation.
Theory-based and heuristic evaluation techniques are promising approaches in
that they 1) provide evaluation at many stages in the design process, 2) remove
the dependence on the availability of representative users and 3) remove the
dependence on highly skilled usability testers. Each of these techniques needs
to be validated by comparing its predictions to rigorous, empirical trials of
real NII applications in real-world use. Also, each of these techniques needs
to be usable by members of typical design teams in real development
A modern engineering discipline requires modeling techniques and simulations to
rapidly manipulate and evaluate design ideas. Design for the NII requires
theories particularly associated with modeling users, their tasks and
activities, work flow processes, environments and human communication. To fill
this need, research is necessary to develop and validate simulations of users,
tasks and environments (i.e., simulated users in a simulated community), of NII
hardware and software technology and of the discourse through which these
entities communicate. The methods for producing and using such simulations must
be themselves usable, cost-effective and usefully fit into the design cycle.
Additional research is required in:
- Cognitive models to simulate different types of individual users who have
different capabilities, backgrounds or training. This would reduce the need to
find people to represent a user group, relaxing the dependence on specialized
user groups like experts or physically challenged users. A start has been made
with the GOMS modeling approach (Card, Moran and Newell) that predicts expert
performance time and learning time, but needs further expansion to other
- Social theories to simulate the sociocultural implications of the NII.
Researchers in computational organization theory have demonstrated initial
progress in predicting behavior of real organizations in real situations, but
continued research is necessary to serve the purposes of the NII.
As design experience accrues through the continuous evaluation of the NII, this
experience could be captured and applied to new designs through heuristic
techniques. Such techniques have started to develop, but need to be expanded to
group applications and validated with observed performance in the field. These
nascent techniques include: "Heuristic Evaluation" (Nielsen), Claims Analysis
(Carroll and Rosson), guidelines, Cognitive Walkthroughs (Lewis and Polson) and
prototyping tools with design critics (Fisher). Research in refining these
methods and creating new ones should be supported to fill the needs of the NII.
3.4 Findings and Recommendations: Standards
The NII needs to establish a core set of user interface standards to provide a
framework for developing products and services that are as ubiquitous and as
easy to use as basic telephony.
User interface standard specifications must ultimately provide uniform hardware
and software benchmarks to measure both performance and compliance. Visible and
explicit evaluation of competing solutions drives technical refinements in the
appropriate direction and rewards cost-effectiveness.
Standards are needed to enable easy-to-use services across different platforms
and different media.
Recommended research should focus on two areas:
- Defining key elements of the user/service functions, capabilities and
commands. For example, the automobile has a small number of standardized
functions (steering, acceleration and braking) that make basic functionality
accessible to all users, but the rest of the automobile is left to the
creativity of the designers. Likewise, research should be done to identify the
core functionality that needs to be standardized for basic use (e.g., the
ability to undo actions, the ability to interrupt processes), leaving the vast
majority of decisions to the ingenuity of NII designers.
- Usability-enabling software, including user-centered application
programming interfaces and protocols to support essential user-level functions
across different devices and platforms.
3.5 Findings and Recommendations: Pilot Projects and Testbeds
Evaluation of the NII itself and its applications should be early, ongoing and
its results should continually feed back into design. One approach would be to
create a national "virtual" user interaction laboratory for defining,
evaluating and conducting research that will foster collaboration and motivate
NII product developers to make ease of use a high priority. There are also
several testbeds already in place that should be studied immediately to begin
the evaluation/design symbiotic relationship. For instance, research should be
conducted into the individual use, social use and cultural implications of
testbeds such as Mosaic, the World Wide Web and NSF's Scientific
Collaboratories so that successes, failures and unexpected results can be
understood and fed back into the design of NII products that come after. New
testbeds and/or pilot projects such as those outlined below should also be
developed to foster further development, introduction and evaluation of new
3.5.1 Health Care
Health care offers many interesting challenges and opportunities.
The realization of "virtual consultation" will:
Patients will be empowered by:
- Improve quality of care by spreading the availability of scarce consulting
- Reduce costs by eliminating travel and duplication of physical
- Improve the timeliness of health care by overcoming geographic barriers to
- Improve the care giver's access to information and colleagues.
- Providing improved access to medical literature, case studies and personal
- Improving care environments with access to support groups.
- Providing home care with remote supervision and monitoring.
- Improving care environments for both care givers and patients by providing
more of the rich social context for interaction that is missing in
unidimensional interactions such as mail, electronic mail and telephony.
Students need interactive access to educators with expertise not locally
available, in either a virtual classroom or monitoring environment. Students
need to collaborate among themselves, forming geographically and culturally
disparate cooperative learning projects.
"Virtual" instruction, tutoring and consultation will:
- Improve the quality of education by allowing greater specialization of
educators, yet greater sharing of that expertise.
- Reduce education costs by spreading the availability of scarce educational
expertise, reducing travel, and sharing information and resources.
- Enable cooperative learning environments and improve the quality of
education, particularly where the social aspects of learning that are so
lacking in "distance education" today are included.
- Improve the quality of education by promoting community and industry
- Improve the scope of successful education by facilitating the education of
many who are awkward socially (and prefer anonymous networked interaction) or
Conference or meeting attendees need to participate without the time and
expense of travel. Spontaneous, informal and low-overhead access (consistent
with the goals of the NII) allows more-productive collaboration between
meetings as well. The potential effects on business are:
- Reducing costs by reducing travel.
- Increasing job opportunities by creating access to jobs--without
collocation/relocation--for those unable to come to the workplace. Job
information can be made available without expensive exploratory travel.
- Potentially changing the face of American business in unforeseen ways,
only understood through social research. Just as the automobile caused the
development of suburbs, use of the NII for work might have equally far-reaching
This area offers the possibility of social games to geographically disparate
(often anonymous) participants. The NII could increase the entertainment market
by adding social dimensions not found in current games, i.e., social dimensions
that appeal to many of the population who do not like current computer-based
entertainment (games of movies).