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10. Time Factors in Interface Design for Augmenting Human Intellect

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The current generation of user interfaces (GUI) is predominantly oriented towards the visual and spatial section of the human cognitive spectrum. A sample of representative articles, like the CHI conferences over the last years, yields an overwhelming percentage of works dealing with visual aspects, and very few dealing with time factors explicitly. A notable exception is Tognazzini (1993), as he explicitly links the factor of time to "magic", and he details the working methods of stage magicians as "manipulations of time" (p. 359). In order to get a better insight into the possible long-terrm effects and consequences of a predominantly visual orientation, we might apply the media theoretical analyses of Innis and McLuhan (Chandler) to HCI paradigms (in Kuhnian, 1962, sense).

It is also instructive to note an apparent theoretical neglect of time factors by computer science (Halang). If we observe industrial systems development in the last 15 years, we get the impression that negative time factors are a prime marketing strategy of the PC industry: systems seem to be purposefully designed to be so slow to be practically useless when they are not run on the latest and most powerful hardware on the market. A closer examination of industry system design policy yields the enormous attraction of GUI design and comparative neglect of time factors: The mass market of "non-computer nerd" users that was opened with the Macintosh has turned out to set a standard that was rigidly adhered to, even where the design limitations of this 1984 machine were since long broken by present hardware power (Common). This translates again into a Kuhnian paradigm, whose stability is not determined by what is technically possible, or rationally advisable, but by social standards of the "least common denominator" and "no experiments, please" flavor. As there is a huge mass market, there is also a tremendous inertia, and no industrial player wants to play the guinea pig trying out any new ideas and approaches, especially not the largest one, who seems to have opted for the technically most inferior possibility (Businessweek). Thus, there has been little progress beyond the basic design decisions of the Macintosh. But, as everyone notices, these "tried and trusted" paradigms seem to be wearing out (Landauer, Norman), the market saturation has peaked, and present systems seem to be headed towards a continuous asymptotic approximation of Dinosaur efficiency.

Time factors were of prime importance in the earlier mini computer generation. Again in Kuhnian sense, there was a complete reversal of paradigms between mini computers, early microcomputers, and the present generation of Macintosh-Style PCs. In the older paradigm of minis, design constraints were imposed by the coupling of a fast hard disk with relatively small computer power (PDP type), which forced the systems designers to painstakingly optimize systems performance around that combination, resulting in such unrepeated feats of temporal efficiency as APL, MUMPS. These were undoubtedly the most powerful programming languages (aka HCI) ever invented by man, and just in terms of pure efficiency, present systems are a big step backwards. But these systems were also cryptic and unforgiving, hard to train, and hard to maintain, and so there were good reasons for the paradigm switch. And, of course, it generates more business volume, when millions of users are catered, than a few thousand.
We come back to the magic: The "olden days" of computing were an age of wizards, and the connection with Tognazzini's article, the "magic factor" gives an indication of a time efficiency that cannot be re-gained by predominantly a visual / spatial oriented framework, once it has given up control of the time factor. One typical effect of the GUI mouse access is, that it slows the user down by about a factor of ten, compared to the very rapid keyboard input of hotkeys (or command line sequences). Of course to be that fast, the user has to have memorized all the command key sequences, and must be a touch-typist. With the complexity of today's menu interfaces, it is impossible to learn them all (especially when every vendor uses different hotkeys for equivalent functions, or, as Microsoft does, creates a new assignment with every new release). As the APL solution shows us, there is a different strategy possible, to contain menu depth and complexity by combinatorial strategies, but this is not easy to learn.

For the "Augmentation of Human Intellect" (Engelbart), the time factor seems to be crucial. Unfortunately, the "magic effect" also causes problems with verification and rationalization by academic standards. This may be a reason why Engelbart has spent a lifetime churning out ideas of which the largest portion still remains to be recognized, let alone be put into wide usage. As was already pointed out, time is a blind spot of computer science (we may read Feyerabend for possible underlying reasons why this may be so). In the literature, there is a body of work around "Flow" (Csikszentmihalyi, Karn 1997: 64). This is a somewhat loose term for hard-to-define intellect-augmentation effects that can occur, when expert work is able to proceed in uninterrupted sequences of cumulative efficiency. In this, the time factor is critical, since it is interrelated with the human attention span and capacity of the short term memory, the best known of which in the 'flicker fusion effect' utilized in movie projection (Pöppel 1978-1995). Maximum time lag of about 1/10 sec seems imperative. Noticeable augmentation effects are attained mainly when a high level of user training and expertise is started with at the beginning. Unfortunately, since the "expert" or "power user" population, that would benefit most from this research, is much smaller than the "general user" population that is catered for by the common GUI interface, the financial rewards for such R&D are too small for large-scale industry efforts. Progress will likely depend on individual efforts, like Engelbart's. In (Goppold), a time oriented HCI design is presented, that seeks to regain the efficiency factors of the former computing generations, but is based on a widely available platform, the Java VM, and extensively uses the hypertext principle to make it accessible for large user populations. A "royal road" to travel is to present an easy "free for all" GUI interface, coupled with an industry standardized end-user programming facility (EUPL), and user interface language (UIL). This way, the would-be power user can design all hotkey and shortcut combinations to her own heart's content. Of all the functionality of a system, less than 10 percent is used regularly. If these functions can be streamlined and programmed individually, the power user community will be ideally catered.

Conclusions: Time factors are an underrepresented but crucial factor in HCI design. Their influence on the "Augmentation of Human Intellect" makes their closer consideration a necessity, since presently, the mass market saturation with PC systems has reached a ceiling, and further improvements cannot be gained by "more features" in "more powerful hardware boxes", but by more "natural intelligence" (as opposed to AI) to augment the power of the user.


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