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What Do We Mean by CHI, Usability and User Interfaces?

Julie Barnes Laura Leventhal

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Sources

• Chapter 2, Protobook

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Definitions of HCI and Usability

• HCI

– human-computer interaction is the discipline concerned with the design, evaluation and implementation of interactive computing systems for human use and with the study of the major phenomena surrounding them.

• UI

– “user interface”

• Usability

– the interface is appropriate for the users for the task that they are using for.

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What we are not...

• We are not interested in "user friendly" - – "user friendly" is an anthropomorphic term. Do

you wish to be friends with your computer?– “user-friendly” suggests a uni-dimensional

attribute. The system is either user friendly or not! Clearly there is a range of user interfaces that are more or less usable.

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Who participates in CHI

• Some backgrounds include– Computer science, Psychology, Anthropology, Artificial

intelligence and many others.

• professional computer scientists often have no formal training in CHI - hence this course.

• Myers (1998) notes– “…If students do not know about user interfaces, they

will not serve industry needs. It seems that only through computer science does HCI research disseminate to products…”

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Why an interest in CHI within the Computing Industry?

• CHI is an emerging topic of interest within the CS community

• This was not always the case. Concern with usability has evolved with computing technologies.

• We are going to review some of the factors which have contributed to a growing interest in CHI

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Technological Innovations Follow a Timeline, Relative to Usability

Innovation Technology is the limiting factor

Demand foroperators

Concernforusability

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Technological Innovations Follow a Timeline

Innovation Technology is the limiting factor

Demand foroperators

Concernforusability

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Stage 1 Examples - Aviation

• “..On December 17, 1903, at Kitty Hawk, North Carolina, the 1903 Wright Flyer became the first powered, heavier-than-air machine to achieve controlled, sustained flight with a pilot aboard.

• The 1903 Wright Flyer was constructed of spruce and ash covered with muslin. The framework "floated" within fabric pockets sewn inside, making the muslin covering an integral part of the structure. This ingenious feature made the aircraft light, strong, and flexible. The 1903 Flyer was powered by a simple four-cylinder engine of the Wrights' own design.

• To fly the airplane, the pilot lay prone with his head forward, his left hand operating the elevator control. Lateral control was achieved by warping the wing tips in opposite directions via wires attached to a hip cradle mounted on the lower wing. The pilot shifted his hips from side to side to operate the mechanism, which also moved the rudder…”

• The pilot also moved one lever to control the forward rudder and a second lever to control a movable tail.

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A Model of the Wright Flyer

The model illustrates the position of the pilot (Orville Wright)

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An Aviation Event of “local” Interest

• From Cedar Point, The Amazement Park: A Historical Perspective, http://www.cedarpoint.com/public/news/history/i.cfm– “..International aviation history was made at the resort on August

31, 1910.  – That was the day pioneer aviator Glenn Curtiss (left) set a record for

the longest over-water flight of his day: 63 miles over Lake Erie. The one-hour, eighteen-minute flight began at a Cleveland amusement park and ended on the Cedar Point beach. The pilot was protected by little else but a bicycle inner tube in the event of a water landing. But he survived and picked up a $15,000 check from Cedar Point for his success. Curtiss' flight was such a sensation he and fellow aviator Tony Jannus returned to the resort over the next few years for exhibition flights that fascinated park visitors.

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Curtiss, 1910

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Stage 2 - Spirit of St. Lewis

• “...On May 21, 1927, Charles A. Lindbergh completed the first solo nonstop transatlantic flight in history, flying his Ryan NYP "Spirit of St. Louis" 5,810 kilometers (3,610 miles) between Roosevelt Field on Long Island, New York, and Paris, France, in 33 hours, 30 minutes.

• The aftermath of the flight was the "Lindbergh boom" in aviation: aircraft industry stocks rose in value and interest in flying skyrocketed. Lindbergh's subsequent U.S. tour in the "Spirit of St. Louis" demonstrated the potential of the airplane as a safe, reliable mode of transportation.

• Because the fuel tanks were located ahead of the cockpit for safety in case of an accident, Lindbergh could not see directly ahead, except by using a periscope on the left side or by turning the airplane and looking out a side window. ..”

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Spirit of St. Louis

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Stage 3 - WWII

• “..Human factors concerns emerged during World War II as a result of the work and experience of a number of specialists involved in the study of then-current manned systems. These systems included those operating on the earthês surface, under the sea, and in space. Human factors studies were made of

– systems performance

– problems encountered in information presentation, detection, and recognition

– related action controls

– workspace arrangement, and

– skills required.

• Research in these areas ensued, with particular emphasis on human operations. This offered the opportunity for early improvements in performance and safety, as significant modifications of equipment were unlikely under wartime circumstances. Attention was focused on operations analysis, operator selection, training, and the environment associated with signal detection and recognition, communication, and vehicle control. Concurrently, human factors work in industry was focused on efficiency, task analysis, and time-and-motion studies…”

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Alphonse Chapanis

• Passed away October 4, 2002• “...Chapanis graduated from Connecticut College for Women (now the University

of Connecticut) and completed his graduate training at Yale (1942) before being commissioned in 1943 as a lieutenant in the Army Air Corps and trained and appointed as an aviation research psychologist. Chapanis was the first research psychologist assigned to the Aero Medical Laboratory (AML) at Wright Field, Ohio. There he became one of a handful of early human factors engineering professionals who researched user-interface problems with air force equipment and developed design solutions during World War II. Chapanis’s applied experimental psychological research work at AML included examinations of pilot errors, testing luminescent materials for cockpit displays, developing anoxia demonstration charts, and especially doing significant work on night vision and dark adaptation issues as well as on other human-machine interface issues for operators of advancing military systems being put through their paces in the second world war…”

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Stage 4 -Modern Flight

• Commercial airliners

• General/civil aviation

• Military aviation

• Rockets and Space shuttles…

• All require complex behaviors of pilots, supported by usable interfaces to controls.

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Lockheed F-117A ‘Nighthawk’

• The Lockheed F-117A was developed in response to an Air Force request for an aircraft capable of attacking high value targets without being detected by hostile radar systems. By the 1970s, special materials and techniques had become available to aircraft designers that would allow them to design an aircraft with radar-evading or "stealth" qualities. The result was the F-117A, the world's first operational aircraft that fully incorporated radar-evading techniques.

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Lockheed F-117A ‘Nighthawk’

QuickTime™ and aPhoto - JPEG decompressor

are needed to see this picture.

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Three Trends in CS Raise Awareness of Usability or How we went from Stage 1 to Stage 4….

• Changes in hardware environment

• Changes and diversification of types/ sophistication of users

• Diversification of software and applications

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Hardware Changes

Memory and Processor Limitations leadbatchProcessing. NoReal notion of “interactivity”

ImprovementsIn memory andProcessor speedFacilitatestime-sharing, a Sort of primitiveinteraction

1980’s1970’s 1990’s

PC’s, workstationsgraphical displaysprocessing power for multimedia andMultimodal Interactions as wellAs alternative Interaction styles.

Improvememts in communications technologies facilitate access to Internet, greatly expanding user populations. Continuing expansion of technologies to support alternative interaction styles

2000’s

Miniturization of hardwareFacilitates developmentOf smaller mini-computers,Explosing new audiencesTo computing.

1950’s 1960’s1949’s

Interaction limitedTo switches andPrimitive I/O

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Summary of Hardware Changes as they relate to Usability

– Computing hardware has become much more powerful in terms of processing speed, storage capabilities and output characteristics.

– The hardware has come ever closer to the user and the ways that a wide cross-section of users are able to interact with it.

– The hardware that the user interacts with directly has become more diversified.

– More devices for input and output have appeared.– As processor capabilities have improved, the opportunities for

different styles of interactions (GUIs, timesharing) became available.

– Improvements in communications technologies to support the Internet has expanded the set of interaction styles and diversified user populations.

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Summary of User Changes and Diversification

• Computing professionals vs. discretionary users• Proportion has changed: more discretionary users • Users are more sophisticated and demanding

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Application Changes and Diversification

1950’s

•batch text•CAD•computational s/w•meteorological•banks

1980’s1970’s

•cheapergraphics•improvedprinters•smallbusiness computing

1990’s / forward

•personal computer apps (eg spreadsheets, word processing)•bit-mapped graphics•hypertext•multimedia

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Summary of Software Changes and Diversification as they relate to Usability

– The software characteristics are as critical in the marketing and sales of computers as the hardware.

• When software use is a personal choice rather than a corporate necessity, usability is a way to entice customers into choosing on application over another.

– The software that the user interacts with directly has become more and more diversified.

– As software has diversified, it supports more interaction styles and multimedia.

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Summary of Stage 1..Stage 4 in CS

• In the early days of CS (Stage 1 and 2)

– Hardware was often built or maintained by the user of the hardware. Many computers were one of a kind.

– Applications were “close” to the hardware (eg. Missile trajectory calculations during WW2).

– Users were experts.

• What about Usability?– Users because they were close to the development of

the machines were able to interact with *primitive* I/O devices and “speak” in binary or assembler languages.

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Summary of Stage 3 in CS

• In the 50’s, 60’s and 70’s (Stage 3)

– Hardware: Processor speed improved, Memory increased

– Software: More and more types of applications, but still essentially for corporations, government, military

– Users: Experts who were trained as computer scientists. These people generally did not become experts by building computers of their own.

• What about Usability

– Demand for skilled operators greatly increased.

– More and more styles of interactions and I/O devices available.

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Stage 3 to Stage 4

• Sometime in the late 1970’s we seem to have arrived at Stage 4.

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By late 70’s HCI is receiving attention within Computer Science

– 1920's - time and motion studies of efficiency of factory work. The Gilbreth’s were pioneers in this area.

– 1900’s - 1920’s - Ford Motor Company revolutionized the role of people in manufacturing with innovations in the assembly line.

– 1940's and 1950's - human factors as a discipline emerges from the problems of designing equipment during WWII. Emphasis on sensory-motor skills, routinization of tasks, stress

– 1960's - some studies of impact of batch vs. online computer use.

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1970’s forward....

– 1971 - Gerald Weinberg The Psychology of Computer Programming (programming as a social activity)

– 1977 - experimental studies of programming language structures by Thomas Green and others.

– 1980 - Ben Shneiderman Software Psychology (ui for programmers)

– 1982 - Gaithersburg conference on Computer - Human Interaction.'

– 1984 - INTERACT'84– 1996 - attendence of CHI96 tops 3000.– 2003 - CHI 2003 in Fort Lauderdale!.

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Summary of Stage 4 in CS

• Now

– Hardware: Explosion of powerful and inexpensive devices

– Software: More and more types of applications including applications for personal life

– Users: Non-experts outnumber experts

• What about Usability

– Products that are not usable are DIFFICULT to sell.

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And now that we are in Stage 4…

• Big issues– How to Improve user interfaces and the user

interface development process– What is included in CHI– What is the future of CHI– How can computer scientists manage to ensure

usability

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How to Improve UI’s?

• little agreement in late 70's and 1980's. Even now, lots of views.– View 1: Follow guidelines - intuitive– View 2: Define and try prototypes - quasi-

experiential– View 3: Experiments: laboratory <------>

observational

• we will look at all three approaches

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Broader Issues

• What HCI is not– It is not just a simple matter to decide whether

to use a menu or a command type of interface, if you consider the problem in its broader perspective and take into account all the factors that influence us and others in regard to using a computer.

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Broader Issues (3)

• no silver bullet• Fig 1.2 (H+H)• The “Undiscovered Country” of HCI

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Ensuring Usability:

• Two components -– The product - the user interface itself

• content, human factors issues, design guidelines and interaction styles.

– The process - how to develop the UI• lifecycle, methods, techniques and tools for

developing and UI

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The behavior vs. constructional domains.

• Table 1.1 H+H. Our focus is on the behavioral domain.

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