HCI - Chapter 1

Historical Context

  • Early Computing (1940s-1980s):

    • Computers were exclusive, complex, and guarded in controlled environments.
    • Access limited to engineers/scientists familiar with tasks like connecting relays, changing memory drums, adjusting JCL stacks, or using Unix commands.
    • Interaction was not a priority for early computer designers.

  • Emergence of Interaction (1980s):

    • Computers became more powerful and usable by the general public.
    • HCI emerged as a field, aligning with the shift of computers to workplaces and homes.

  • Research in HCI:

    • Drives advances incorporated into widely used products and processes.
    • Includes design but focuses on the what, why, and how of research.
    • User studies are formal experiments with human participants.
    • Empirical research is based on observation and experience that can be verified by other researchers.

Origin of HCI

  • Influence of Human Factors/Ergonomics:

    • HCI owes much to human factors, concerning human capabilities, limitations, and performance.
    • Focuses on designing efficient, safe, comfortable, and enjoyable systems.
    • HCI narrows human factors to interaction with computing technology.

  • Interdisciplinary Nature:

    • HCI incorporates expertise from psychology, sociology, anthropology, cognitive science, computer science, and linguistics.

Key Developments in HCI History

  • Timeline:
    • A timeline of notable events leading to the development of HCI as a field of study, beginning in the 1940s

Vannevar Bush’s "As We May Think" (1945)

  • Relevance to HCI:

    • Bush's essay is still relevant in HCI courses, addressing knowledge dissemination, storage, and access.
    • He foresaw information overload and the need for efficient information navigation.

  • Memex:

    • Bush proposed the memex, a device with associative indexing to connect related items.
    • This concept resembles hyperlinks and bookmarks.
    • Inspired by the contemporary telephone exchange, he envisioned a web of interconnected information.

Ivan Sutherland’s Sketchpad (1962)

  • Graphics System:

    • Developed as part of Sutherland's PhD research at M.I.T.
    • Supported manipulation of geometric shapes and lines using a light pen.

  • Direct Manipulation:

    • Allowed users to draw, resize, move, and delete objects directly.
    • Commands were not typed, representing a major shift in human-computer interaction.

  • Constraints:

    • Object manipulations maintained geometric relationships and properties.

  • First Direct Manipulation Interface:

    • Considered the first direct manipulation interface; a term later coined by Ben Shneiderman.

  • Features of Direct Manipulation:

    • Visibility of objects, incremental action, rapid feedback, reversibility, exploration, syntactic correctness, and replacing language with action.

Invention of the Mouse (1963)

  • Douglas Engelbart's Invention:

    • Invented by Douglas Engelbart at the Stanford Research Institute (SRI).
    • Revolutionized human-computer interaction by allowing users to control an on-screen cursor.

  • Motivation:

    • Developed as a replacement for the light pen, which caused fatigue.
    • A desktop device near the keyboard was a more natural solution.

  • Prototype:

    • Included two potentiometers at right angles, connected to wheels that rotated with movement.
    • Voltage changes from wheel rotation controlled the cursor's x and y positions.

First User Study

  • Comparative Evaluation:

    • Engelbart, English, and Berman conducted an experiment comparing the mouse with a light pen, joystick, knee-controlled lever, and Grafacon.
    • Evaluated selection and x-y position control of an on-screen cursor.

  • Devices Compared:
    * Light Pen: Held in the air, caused fatigue.
    * Joystick: Moving stick with absolute/position-control mode and rate-control mode.
    * Knee-Controlled Lever: Controlled x-y cursor movement, rocking motion on foot.
    * Grafacon: Used for tracing curves.

Mouse Evaluation and Results

  • Metrics: Measured access time (hand from keyboard to device) and motion time (cursor movement to selection).

  • Participants: Included 13 participants (8 experienced; 3 inexperienced).

  • Procedure: Participants moved the cursor to a target on the display and made a selection.

  • Results:

    • The light pen had a slight advantage in motion time.
    • The mouse was more accurate, with a lower error rate.
    • The knee-controlled lever had zero access time because of hand placement, but wasn't competitive in motion time.

  • Mouse Refinement

    • The potentiometer wheels were replaced with a rolling ball assembly

  • Significance:

    • The evaluation was a milestone in empirical HCI research.
    • Included detailed descriptions of participants, apparatus, and procedure.

  • Variables:

    • Independent variable: input method (mouse, light pen, joystick, knee-controlled lever).
    • Dependent variables: task completion time and error rate.
    • Counterbalancing was used to vary the order of device conditions.

Xerox Star (1981)

  • GUI Pioneer:

    • The Xerox 8100 Star Information System was the first commercial computer with a GUI.
    • Features included windows, icons, menus, and a pointing device (WIMP).
    • Supported direct manipulation and WYSIWYG interaction.

  • Development:

    • Developed at Xerox PARC, building on the Alto (Star's predecessor).
    • Xerox licensed the mouse from SRI.

  • Workstation Features:

    • Included a bit-mapped display.
    • Graphical information was novel, used a two-button mouse.

  • Office Automation:

    • Intended as an office automation system.

  • Desktop Metaphor:

    • Used icons representing documents, folders, trays, and accessories to mirror an office desktop.
    • The metaphor made the system user-friendly by drawing on existing knowledge.

  • File-Based Interaction:

    • Focused on files rather than programs.
    • Users