Inventing and Evolving Human-Computer Interfaces:
Five Spheres of Invention

Davis Foulger
Visiting Associate Professor
Oswego State University

April 15, 2002

The Study of Human-Computer Interaction:

(A small sampling of topics from the upcoming ACM SIGCHI meeting:)

A study of computer conferencing:

• I joined IBM in 1983
  • my purpose was to study computer conferencing
• The group I joined was ground zero for conferencing in IBM
  • the group that was making it happen
• I was able to observe everything
  • Participation
  • System Management
  • Group Management
  • Rules Formation and Enforcement
    • Both formal and informal
  • The development of
    • the back end
    • the connective fibre (the network)
    • user interfaces
    • uses
    • communities
• The result was an eight year study of computer conferencing in IBM
  • participant observation
  • discourse analysis
  • limited use of surveys
  • traversing the entire diffusion of innovation curve
• Of course, IBM had other things for me to do, but more on that later

I Observed a Process of Continuous Change:

• in computer conferencing
  • new uses
  • problems
  • solutions to problems in the form of
    • informal rules
    • systemic practice
    • local (specialized forum) rules
    • generic practice
    • formal rules
    • new system elements
  • with care taken to preserve,
    • and occasionally improve,
      • the character of the system
• in the software and systems I was building
  • we leveraged conferencing in adopting a new model for development
    • distributing software in beta test electronically
    • taking feedback via forums (computer conferences)
    • handling bug reports and new feature requests in near real time
  • with new version turnaround times sometimes measured in hours
    • iterative development
    • what would now be called extreme programming

Along the way, I found a problem with "problems"

• a key element of the CC study was identification of:
  • benefits
  • problems
• The benefits were going great.
  • People kept finding new new ways to use conferencing
  • People kept finding new benefits of using conferencing
  • Every survey found more benefits
  • Every benefit mattered
  • And no benefit ever seemed to go away
• But the problems kept disappearing
  • Every problem people came up with seemed to be
    • an opportunity to have a conversation
      • and come up with one or more solutions
  • Every survey found new problems
  • But the old problems seemed to disappear
• Not all went away,
  • but the ones that didn't go away were usually hard to solve
    • without changing something else that mattered
• The same was true for my software development
  • informal enhancements
  • a desire for formal configurability
  • a willingness to take over software if development slowed

And there seemed to be a pattern to the change:

A theory, initially rooted in Simon's Sciences of the Artificial, fell out.

• The initial version of this theory opens my dissertation
• A more recent precis of it is available as well

I extend Simon with invention processes in the outer environment

Five interacting spheres of invention and evolution: Mediators, the stuff the system is made of and the way its put together Characteristics, the essential qualities of the system Uses, the things we do with the system Effects, the things that happen as a result of use Practices: the rules and practices we create to make the system more functional Two+ cycles of change of media (or artifact) of genre (or application) Used to describe media, but appears to be more general

Media are only one form of communication-enabling artifact:

• In computer-mediated systems, the computer is a part of the medium
• In direct human-computer interaction, the computer alternates in the roles of:
  • communicator
  • audience
• One might regard this as a view of the larger "outer environment" of an artifact
• All human-computer interaction occurs within the context of a medium
  • In some cases, our purpose in designing an HCI system is to create a medium
  • In others, we embed a medium in an application (or an application in a medium)
• I'll explain each below, but first lets look at a HCI example:

A real world example (IBM Research; 1984):

Mediators	the IBM XT ships with a 10 Megabyte hard disk and a subdirectory capable DOS
Characteristics	the root directory is limited to 254 files or directories
Uses	new users load up the operating system, a text editor, and start writing documents
Practices	because they didn't read the documentation and were used to VM, they saved all their files to the root directory
Effects	when they try to save the 255th file, it won't save
Practices	they call up their local PC Consultant
Effects	several hours are spent diagnosing the problem and moving files, one at a time, into a subdirectory structure
Practices	the user is instructed to save their files to subdirectories and shown how
Effects	other users have the same problem
Practices	a text editor is used to create a batch file that moves the files around
Effects	several hours are saved, but other users have the same problem
Mediators	a batch file is written that automatically moves the files around
Effects	more time is saved, but users aren't happy with were the files are put
Mediators	a direct file manipulation program is created (File Manager)
Uses	users can easily reorganize their own systems
Effects	they do, but notice that the file manager makes a good user interface
Uses	they start using it as a user interface
Effects	some things are hard to do
Practices	requests are made for new features
Mediators	the file manager is given end user configurability features
Effects	a new game emerges as a biproduct: Hard disk roulette
Practices	the game is documented as a "dangerous" feature
Mediators	the application features that enable the game are disabled
Practices	end users start using and sharing customizations
The Cycle of Genre	the file manager grows other uses, including "Backup"
The Cycle of Media	the file manager grows into, well, "File Manager" (OS/2 and Windows) "DOS Shell" a pre-X-Windows UNIX shell The original code is still being improved 18 years later (by its seventh "owner").
Mediators	a default directory structure is built into a new user "workbench" along with a configurable menu-based user interface system a set of applications and built in (hypermedia) documentation
The Cycles of Media and Genre	The workbench and all the tools in it grow too, but that's several more stories, and the file management story is pretty sketchy

Mediators are the "clockworks" of an medium

• Components and their organization
• The subject of systems theory and information theory, among others
• Categories of media technology include:
  • modalities (the interfaces of the organism)
  • interfaces (reception, production, and controls)
  • carriers
    • natural (air, light, touch, organism memory)
    • artificial (clay, paper, electricity, modulated light)
  • memory
    • natural (tooled natural materials, organism memory)
    • artificial (clay, paper, electronic recording media)
  • filters (concentrators, resistors, modifiers, and translators)
  • amplifiers (volume control, manufacturing, and signal maintenence)
  • routers (direction and selection)
  • envelopes (addressing and labeling)
• The real issue is the organization of mediators
  • Selection
  • Placement
  • Relationship (association, directionality, and ownership)
• One can make significant changes to mediators without changing the medium
• One can build significantly different media with the same mediators

Characteristics are the essential qualities of a medium

• The abstracted "possibilities" of a particular structuring of mediators
• The characteristics of media determine:
  • the kinds of things that a medium will be good at
  • the media it will most directly compete with
  • its prospects for success

Useful Groupings: modalities message performance production participants creator consumer channel storage interface marketplace Dimensions (see figure at right): Amplification (vertical) Dynamism (from left) Bandwidth (from right) Focus of Book

Uses

Effects

• No system is ever used without effects
• Application effects
  • Those that are desired by users
  • If uses don't work out, the artifact will be abandoned
  • If uses do work out, there will be pressure to optimize these effects
• Outcome effects
  • The accidental biproducts of use
  • In some cases new uses
    • these rapidly convert to application effects
  • In most cases, at least the perception of trouble
    • Three rules of media
      • A medium is young and promising when people talk about its potential value in education
      • A medium is approaching or passing the lower knuckle of the diffusion of innovation curve when people complain about its use for pornography
      • A medium is approaching or passing the upper knuckle of the diffusion of innovation curve when people complain that it isn't used in education
• Effects are invented by users of the artifact
  • and other stakeholders in the outer environment in which the artifact is used
• They are often a matter of perspective and controversy
  • one person's application effect is often anothers outcome effect
• They are often fleeting
  • The Problem with "Problems"

Practices

• The things participants do, when using a medium
  • to maximize its effectiveness
  • to minimize its problems
• As with the other spheres, they are inventions
• Practices generally take two forms:
  • Constraints, including rules, norms, roles, and enforcement
    • Generally act to minimize problems (e.g. don't do that)
    • Are most often enacted in response to perceived harms
    • Can be recognized in processes of negotiation
    • And attempts at enforcement
    • Constraints may be formal or informal
    • But anarchist protestations aside, they always occur
    • A fourth rule:
      • You know a medium is genuinely new when people invoke wild west metaphors to describe it.
  • Strategies, including games, rhetorics, and other behavior
    • Generally act to maximize the effectiveness of the medium
    • Are most often enacted because they seem to work
    • Can be recognized in
      • repeated patterns of behavior
      • recurring structures
    • Are rarely the subject of sanctions or other enforcement
• Practices can be generic or system
  • Generic constraints and strategies are tied to specific uses of an artifact
    • Are expressed in the "Cycle of Genre"
  • Systemic constraints and strategies apply regardless of how an artifact is used
    • Are expressed in the "Cycle of Media

The Disconnect in Development

Applications, Artifacts, and Media are developed in five spheres of invention We generally develop in two of them: Mediators Characteristics With use cases, we consider a third: Uses but the wrong uses and the wrong users And we generally don't consider effects or practices: limited beta testing limited or no research after first ship limited or no end user configurability Design patterns and anti-patterns are a step in the right direction but every system is different only observation of use will inform effects and practices.

Conclusion

• One could go on endlessly
• Every successful medium I have ever looked at
  • demonstrably traverses the cycles of medium and genre
    • on a continuing basis
• Every unsuccessful medium I have ever looked at
  • generally failed to generate uses
    • or had its uses stolen by another medium
• Every successful program I have ever worked on
  • demonstrably traversed the cycles of medium and genre
    • on a continuing basis
• Every unsuccessful program
  • either failed to generate secondary uses
    • or had unexpected effects that weren't worth fixing
• Henry Petroski's work (The Pencil and The Evolution of Everyday Things)
  • fully demonstrates the interactions of the spheres of invention
    • for example, his discussion of pencils, hammers, and paper clips
• Systems don't evolve to meet abstract goals
• They evolve in response to use
  • with ongoing invention in both the inner system
    • mediators
    • characteristics
  • and the outer environment (the cycle of genre)
    • uses
    • effects
    • practices