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4.2 General Conception of HCI Engineering Design Practice 150 150 John

4.2 General Conception of HCI Engineering Design Practice

The General Conception pre-supposes an associated HCI Engineering Discipline (F1) comprising: HCI Engineering knowledge, which distinguishes the interactive system of user and computer, the tasks it performs as desired and the goodness of that performance in terms of specific criteria (C1) The practice is supported by HCI Engineering knowledge seeking to solve design problems. Design problems here include specification, followed by implementation, of users interacting with computers (the interactive system) to perform tasks as desired in some domain of application. (C3)

The HCI Engineering Conception, then, is unequivocally one of design practice. (F2) HCI Engineering practice is the product of research practice and design practice itself. Such practice is public and ultimately formal. (F3) It may assume a number of forms, for example, codified, proceduralised, formal etc, as in methods, theories, principles etc. It may be maintained in a number of ways; for example, it may be expressed in journals, learning systems, procedures, tools, methods etc. HCI Engineering practice is, therefore, a necessary characteristic of the HCI Engineering Discipline. (C2)

The discipline of HCI Engineering, aims (in the longer term) to solve its general problem of design by the specification of designs before their implementation – as in ‘specify then implement’ design practices. (C6) (C7) (C9) The latter is made possible by the prescriptive nature of the knowledge supporting such practices – knowledge formulated as HCI Engineering methodological (and substantive) principles. (C4)

However, a pre-requisite for the formulation of any HCI Engineering principles is a Conception. The Conception, from which the HCI Engineering Conception is generalised, is a unitary view of the HCI Engineering design problem; its power lies in the coherence and completeness of its definition of the concepts, which can express that problem. (F4) (C8) (C12)

Engineering principles are articulated in terms of those self-same concepts. The latter include: user; computer; interaction; task; domain of application; system; and desired performance (for a full listing – see 2.2).

Thus, the Conception of HCI Engineering methodological (and substantive) principles assumes the possibility of a codified, general, and testable formulation of HCI Engineering discipline knowledge and practice. The latter might be prescriptively applied to designing humans and computers interacting to perform tasks as desired. Such principles would be unequivocally formal and operational. Indeed, their operational capability would derive directly from the formality of their concepts. (C4) HCI Engineering methodological (and substantive) concepts would be generalisable over classes of design problem solutions. Since the principles are operational, their application (expressed as design solutions) would necessarily be specifiable. They would also be testable and so their reliability and generality could also be specified. (C5)

In this way would the principles, expressed in terms of the Conception of Engineering design practice, be validated Such validated Engineering methodological (and substantive) design principles would offer a better guarantee (that is, more assurance – see 3.6.1)) of solving the HCI general design problem. Better, for example, than the experiential trial-and-error practice of craft HCI or the guidelines/heuristics and methods of Applied Science HCI. (C11)

HCI Engineering principles, following the Conception of Engineering design practice, can be methodological and substantive. Methodological principles prescribe the methods for solving the general HCI design problem. Methodological principles would assure complete specification of all necessary levels of design solution representation. Substantive principles prescribe the features and properties of HCI systems that constitute solutions to the HCI Engineering design problem. (C10)

The extent, to which HCI engineering principles might be realiseable in practice, in the longer term, remains to be seen and demonstrated. In the meantime, craft practice (F5) in whatever form – models, methods, heuristics, guidelines, experience, procedures etc cannot be other than recruited to solve HCI design problems both by researchers and practitioners. (C13)

Key concepts are shown in bold on their first appearance only.

Footnotes and Citations

Footnotes

(F1) The contrast here with Engineering is Science, which has its own discipline problem, knowledge and practices.

(F2) See (F1)

(F3) For the present purposes, Engineering, in its early craft stages, is not addressed.

(F4) Other HCI Engineering conceptions, other than that of the EU, might, of course, also be postulated.

(F5) See (F3)

Citations

Long and Dowell (1989)

(C1) ‘The framework expresses the essential characteristics of the HCI discipline, and can be summarised as: ‘the use of HCI knowledge to support practices seeking solutions to the general problem of HCI’. (Page 9, Lines 16-19)

(C2) ‘All definitions of disciplines make reference to discipline knowledge as the product of research or more generally of a field of study. Knowledge can be public (ultimately formal) or private (ultimately experiential). It may assume a number of forms; for example, it may be tacit, formal, experiential, codified – as in theories, laws and principles etc. It may also be maintained in a number of ways; for example, it may be expressed in journals, or learning systems, or it may only be embodied in procedures and tools. All disciplines would appear to have knowledge as a component (for example, scientific discipline knowledge, engineering discipline knowledge, medical discipline knowledge, etc). Knowledge, therefore, is a necessary characteristic of a discipline.’ (Page 11, Lines 30-38)

(C3) ‘The discipline of engineering may characteristically solve its general problem (of design) by the specification of designs before their implementation. It is able to do so because of the prescriptive nature of its discipline knowledge supporting those practices – knowledge formulated as engineering principles.’ (Page 24, Lines 11-14)

(C4) ‘The conception of HCI engineering principles assumes the possibility of a codified, general and testable formulation of HCI discipline knowledge which might be prescriptively applied to designing humans and computers interacting to perform work effectively. Such principles would be unequivocally formal and operational. Indeed their operational capability would derive directly from their formality, including the formality of their concepts.’ (Page 24, Lines 28-31)

(C5) ‘First, HCI engineering principles would be a generaliseable knowledge. …….. Second, engineering HCI principles would be operational, and so their application would be specifiable…….. Because they would be operational, they would be testable and their reliability and generality could be specified.’ (Page 27, Lines 20-22 and 36-28)

Dowell and Long (1989)

(C6) ‘The paper .….. examines the potential for Human Factors to formulate engineering principles. ……… A conception would provide the set of related concepts which both expressed the general design problem more formally, and which might be embodied in engineering principles.’ (Page 1513, Lines 9 and 10)

(C7) By comparing the HF general design problem with other, better-understood, general design problems, and by identifying the formal knowledge possessed by the corresponding disciplines, the potential for HF engineering principles is suggested.’ (Page 1514, Lines 15-18).

(C8) ‘However, a pre-requisite for the formulation of any engineering principle is a conception. A conception is a unitary (and consensus) view of a general design problem; its power lies in the coherence and completeness of its definition of the concepts, which can express that problem. Engineering principles are articulated in terms of those concepts.’ (Page 1514, Lines 23-27)

(C9) ‘Generally, the established engineering disciplines possess formal knowledge: a corpus of operationalised, tested, and generalised principles. Those principles are prescriptive, enabling the complete specification of design solutions before those designs are implemented (see Dowell and Long, 1988b).’ (Page 1520, Lines 1-5)

(C10) ‘Engineering principles can be substantive or methodological. Methodological Principles prescribe the methods for solving a general design problem optimally. ……Methodological principles would assure each lower level of specification as being a complete representation of an immediately higher level. Substantive Principles prescribe the features and properties of artefacts, or systems that will constitute an optimal solution to a general design problem. (Page 1520, Lines 6-15)

(C11) ‘The contemporary HF discipline does not possess either methodological or substantive engineering principles. The heuristics it possesses are either ‘rules of thumb’ derived from experience or guidelines derived from psychological theories and findings. Neither guidelines nor rules of thumb offer assurance of their efficacy in any given instance, and particularly with regard to the effectiveness of a design. The methods and models of HF (as opposed to methodological and substantive principles) are similarly without such an assurance. (Page 1520, Lines 21-28)

(C12) ‘Such a conception ….. enables the formulation of engineering principles which embody and instantiate those concepts.( Page 1520, Line 1)

(C13) ‘The extent to which HF engineering principles might be realisable in practice remains to be seen. It is not supposed that the development of effective systems will never require craft skills in some form, and engineering principles are not seen to be incompatible with craft knowledge, particularly with respect to their instantiation. At a minimum, engineering principles might be expected to augment the craft knowledge of HF professionals. Yet the great potential of HF engineering principles for the effectiveness of the discipline demands serious consideration.’ (Page 1533, Lines 24-29)

 

4.3 EU Conception of HCI Engineering Design Practice: a Summary 150 150 John

4.3 EU Conception of HCI Engineering Design Practice: a Summary

The EU Conception of HCI Engineering Design Practice presupposes an associated HCI Engineering Discipline, comprising: HCI engineering knowledge (C2), which distinguishes the interactive system of user and computer, the work it performs and the effectiveness of that performance, in terms of task quality and system resource costs (C1). This HCI design practice is supported by HCI knowledge seeking to diagnose design problems and to prescribe design solutions to those problems. (C5) (15) The EU Conception of the HCI Engineering design problem is informally expressed as: to design human interactions with computers for effective working. (C16) (C24) (C25) The EU Conception, then, is unequivocally one of design practice. HCI Engineering practice, following the EU Conception, is supported by research. (3) (17) Such practice is public and ultimately formal. It may assume a number of forms, for example, codified, proceduralised, formal etc, as in methods, guidelines etc. (C28) (30) It may be maintained in a number of ways, for example, it may be expressed in journals, learning systems, procedures, tools etc. (C4) HCI Engineering practice is, therefore, a necessary characteristic of the EU HCI Engineering Discipline. (C15) The discipline of HCI Engineering, aims, following the EU Conception, (in the longer term (F1)) to solve its general problem of design by the specification of designs before their implementation – as in ‘specify then implement’ design practices. (C26) (C27) The latter is made possible by the prescriptive nature of the knowledge supporting such practices – knowledge formulated as HCI Engineering principles, both methodological and substantive. (C29) However, a pre-requisite for the formulation of any HCI Engineering principles is a Conception. (C2) (C7) The EU Conception is a unitary view of the HCI Engineering design problem; its power lies in the coherence and completeness of its definition of the concepts, which can express that problem. (C1) Engineering methodological (and substantive) principles are articulated in terms of those self-same concepts. The latter include: user; computer; interaction; work; work domain; worksystem; effectiveness; performance; task quality; system resource costs etc (see 2.5 for a complete presentation of the EU design problem concepts, which would be recruited to the formulation of EU-conceived engineering methodological (and substantive) principles. (C1) (F2) Thus, the EU Conception of HCI Engineering methodological (and substantive) principles assumes the possibility of a codified, general, and testable formulation of HCI Engineering discipline. (C4) (C28) The latter might be prescriptively applied to designing humans and computers interacting to perform work effectively. (1) Such principles would be unequivocally formal and operational. Indeed, their operational capability would derive directly from the formality of their concepts. (C6) EU HCI Engineering methodological (and substantive) concepts would be generalisable over classes of design problem solutions. Since the methodological (and substantive) principles are operational, their application (expressed as design solutions) would necessarily be specifiable. (C6) (C26) They would also be testable and so their reliability and generality could also be specified. (C28) (29) In this way would the methodological (and substantive) principles, expressed in terms of the EU Conception of Engineering design practice, be validated. Such validated Engineering design principles would offer a better guarantee (that is, more assurance) of solving the HCI general design problem. Better, for example, than the experiential trial-and-error knowledge of craft HCI (C6) (C13) (C14) (C19) (20) (C21) (C22) or the guidelines/heuristics and methods of Applied Science HCI (C3) (F3) HCI Engineering principles, following the EU Conception of Engineering design knowledge, can be substantive or methodological. Methodological principles prescribe the methods for solving the general HCI design problem. (1) Methodological principles would assure complete specification of all necessary levels of design solution representation. (C6) Substantive principles prescribe the features and properties of HCI systems that constitute solutions to the EU HCI Engineering design problem. (C6) The extent, to which HCI engineering methodological (and substantive) principles might be realisable in practice, in the longer term, remains to be seen and demonstrated. (C6) In the meantime, craft knowledge in whatever form – models, methods, heuristics, guidelines, experience, procedures etc cannot be other than recruited to solve HCI design problems both by researchers and practitioners (C18) (C19) (C20) (C21) (C22) (C23) (F4)

Key concepts are shown in bold on their first appearance only.

Footnotes and Citations

Footnotes

(F1) In the shorter term, to solve HCI design problems, either for research design practice or for design practice itself, any type of knowledge, for example, methods, guidelines etc might be used.

(F2) Or indeed to other types of Engineering knowledge, for example, models and frameworks, intended to support the diagnosis of design problems and the prescription of their design solutions.

(F3) Craft HCI would also include craft engineering HCI – see also (F1) and (F2).

(F4) See also (F1), (F2) and (F3).

Citations

Long and Dowell (1989)

(C1) ‘The framework expresses the essential characteristics of the HCI discipline, and can be summarised as: ‘the use of HCI knowledge to support practices seeking solutions to the general problem of HCI’. (Page 9, Lines 16-19)

(C2) ‘ Some would claim HCI theory as explanatory laws, others as design principles. Some would claim HCI theory as directly supporting HCI practice, others as indirectly providing support. Some would claim HCI theory as effectively supporting HCI practice, whilst others may claim such support as non-existent.’ (Page 10, Lines 12-17)

(C3) ‘All definitions of disciplines make reference to discipline knowledge as the product of research or more generally of a field of study. Knowledge can be public (ultimately formal) or private (ultimately experiential). It may assume a number of forms; for example, it may be tacit, formal, experiential, codified – as in theories, laws and principles etc. It may also be maintained in a number of ways; for example, it may be expressed in journals, or learning systems, or it may only be embodied in procedures and tools. All disciplines would appear to have knowledge as a component (for example, scientific discipline knowledge, engineering discipline knowledge, medical discipline knowledge, etc). Knowledge, therefore, is a necessary characteristic of a discipline.’ (Page 11, Lines 30-38)

(C4) ‘Craft disciplines solve the general problems they address by practices of implementation and evaluation. Their practices are supported by knowledge typically in the form of heuristics; heuristics are implicit (as in the procedures of good practice) and informal (as in the advice provided by one craftsperson to another). Craft knowledge is acquired by practice and example, and so is experiential; it is neither explicit nor formal.’ (Page 16, Lines 4-8)

(C5) ‘…….. the (public) knowledge possessed by HCI as a craft discipline is not operational. That is to say, because it is either implicit or informal, it cannot be directly applied by those who are not associated with the generation of the heuristics or exposed to their use. If the heuristics are implicit in practice, they can be applied by others only by means of example practice. If the heuristics are informal, they can be applied only with the help of guidance from a successful practitioner (or by additional, but unvalidated, reasoning by the user).’ (Page 18, Lines 28-33)

(C6) ‘If craft knowledge is not testable, then neither is it likely to be generalisable ……To be clear, if being operational demands that (public) discipline knowledge can be directly applied by others than those who generated the knowledge, then being general demands that the knowledge be guaranteed to be appropriate in instances other than those in which it was generated. Yet, the knowledge possessed by HCI as a craft discipline applies only to those problems already addressed by its practice, that is, in the instances, in which it was generated.’ (Page 19, Lines 11 and 15-20)

(C7) ‘The discipline of science uses scientific knowledge (in the form of theories, models, laws, truth propositions, hypotheses, etc.) to support the scientific practice ……..Scientific knowledge is explicit and formal, operational, testable and generalisable. It is therefore refutable (if not proveable, Popper [1959])’. (Page 20, Lines 2-3 and 7-9)

(C8) ‘An applied science discipline is one which recruits scientific knowledge to the practice of solving its general problem – a design problem.’ (Page 20, Lines 16 and 17)

(C9) ‘ First, its science knowledge cannot be applied directly, not – as in the case of craft knowledge – because it is implicit or informal, but because the knowledge is not prescriptive; it is only explanatory and predictive. Its scope is not that of the general problem of design.’ (Page 23, Lines 20-23)

(C10) ‘Second, the guidelines based on the science knowledge, which are not predictive but prescriptive, are not defined, operationalised, tested or generalised with respect to desired effective performance. Their selection and application in any system would be a matter of heuristics (and so paradoxically of good practice).’ (Page 23, Lines 25-28)

(C11) ‘Science knowledge is explicit and formal, and so supports reasoning about the derivation of guidelines, their solution and application (although one might have to be a discipline specialist so to do).’ (Page 23, Lines 36-38)

(C12) ‘The discipline of engineering may characteristically solve its general problem (of design) by the specification of designs before their implementation. It is able to do so because of the prescriptive nature of its discipline knowledge supporting those practices – knowledge formulated as engineering principles.’ (Page 24, Lines 11-14)

(C13) ‘The conception of HCI engineering principles assumes the possibility of a codified, general and testable formulation of HCI discipline knowledge which might be prescriptively applied to designing humans and computers interacting to perform work effectively. Such principles would be unequivocally formal and operational. Indeed their operational capability would derive directly from their formality, including the formality of their concepts.’ (Page 24, Lines 28-31)

(C14) ‘First, HCI engineering principles would be a generaliseable knowledge. …….. Second, engineering HCI principles would be operational, and so their application would be specifiable…….. Because they would be operational, they would be testable and their reliability and generality could be specified.’ (Page 27, Lines 20-22 and 36-28)

(C15) ‘ Although all three conceptions address the general problem of HCI, they differ concerning the knowledge recruited to solve the problem. Craft recruits heuristics; applied science recruits theories expressed as guidelines; and engineering recruits principles.’ (Page 28, Lines 22-24)

Dowell and Long (1989)

(C16) ‘The paper ….. examines the potential for Human Factors to formulate engineering principles. ……… A conception would provide the set of related concepts which both expressed the general design problem more formally, and which might be embodied in engineering principles.’ (Page 1513, Lines 9 and 10)

(C17) ‘However, a pre-requisite for the formulation of any engineering principle is a conception. A conception is a unitary (and consensus) view of a general design problem; its power lies in the coherence and completeness of its definition of the concepts, which can express that problem. Engineering principles are articulated in terms of those concepts.’ (Page 1514, Lines 23-27)

(C18) ‘Most definitions of disciplines assume three primary characteristics: a general problem; practices, providing solutions to that problem; and knowledge, supporting those practices.’ (Page 1514, Lines 43-45)

(C19) ‘Generally, the established engineering disciplines possess formal knowledge: a corpus of operationalised, tested, and generalised principles. Those principles are prescriptive, enabling the complete specification of design solutions before those designs are implemented (see Dowell and Long, 1988b). This theme of prescription in design is central to the thesis offered here.’ (Page 1520, Lines 1-5)

(C20) ‘Engineering principles can be substantive or methodological. Methodological Principles prescribe the methods for solving a general design problem optimally. ….. Methodological principles would assure each lower level of specification as being a complete representation of an immediately higher level. Substantive Principles prescribe the features and properties of artefacts, or systems that will constitute an optimal solution to a general design problem. (Page 1520, Lines 6-15)

(C21) ‘Such a conception ….. enables the formulation of engineering principles which embody and instantiate those concepts. ( Page 1520, Line 46 and Page 1521, Line 1)

(C22) ‘The extent to which HF engineering principles might be realiseable in practice remains to be seen. It is not supposed that the development of effective systems will never require craft skills in some form, and engineering principles are not seen to be incompatible with craft knowledge, particularly with respect to their instantiation. At a minimum, engineering principles might be expected to augment the craft knowledge of HF professionals. Yet the great potential of HF engineering principles for the effectiveness of the discipline demands serious consideration.’ (Page 1533, Lines 24-29)

Halimahtun Mohd Khalid PhD 150 150 John

Halimahtun Mohd Khalid PhD

Date of PhD:

17 January 1990

Thesis Title:

Human Factors of Integrating Speech and Manual Input Devices: The Case of Computer Aided Design

Pre-PhD Background:

M.Sc. Applied Experimental Psychology (Monash University); M.Sc. (Prelim.) Behavioural Sciences (La Trobe University).

Pre-PhD View of HCI/Cognitive Ergonomics:

HCI was an emerging discipline and very little was published in the literature. At that time the prevailing interest was CHI which focused on design of computer systems for interacting with users. Physical Ergonomics was well established, while Cognitive Ergonomics was almost unknown. Cognitive Science was well documented especially Psychology. The application of Cognitive Psychology to Ergonomics problems in order to understand the design of user interfaces of products and systems became an exciting area for research. The Ergonomics Unit at UCL was a pioneer in Cognitive Ergonomics.

Post-PhD View of HCI/Cognitive Ergonomics:

The initial development of HCI/Cognitive Ergonomics in UK bears the mark of Professor John Long, who took the discipline to a higher level. His emphasis on theory development in all PhD work suggests his important contribution to theory-building and methods development. His students may not have lived up to his expectations, but the seeds of reason have been sowed and created a new challenge and mindset for the transformed centre, UCL Interaction Centre, or UCLIC.

The first Handbook of Human-Computer Interaction by Martin Helander appeared in 1988. The contents were still CHI-driven with contributions from scientists in the Computer Science field.

The early works of the Ergonomics Unit (prior to UCLIC) emphasised on HCI/Cognitive Ergonomics in various application domains, including: teleshopping, training, postal services, naval displays & control, computer aided design. All of this contributed to the growing discipline.

The concept of usability emerged in tandem with better understanding of user interface design. Multimedia too became an important research area for HCI/Cognitive Ergonomics.

Subsequent-to-PhD View of HCI/Cognitive Ergonomics:

Today the discipline has expanded ubiquitously. But Theory development has not expanded much. Many theories and methods are still borrowed from the Behavioural Sciences, in particular Psychology. There is no theory of HCI!

The literature in this area is based on research which is not grounded in theory, relative to research in psychology. The rigour of scientific research lags behind the desire to produce quick results for the sake of publication.

There is a need for experts in HCI/Cognitive Ergonomics to come together and focus on theory development to support rapid development in computer and communications technologies. Products and systems are getting more difficult to use, especially for the aged population.

Additional Reflections:

I was introduced to HCI/Cognitive Ergonomics in 1985 when I presented a paper at the Ergonomics Society conference at the University of Nottingham. John Long, the guru, who became my supervisor afterwards, presented papers on design of naval information displays and also on teleshopping. I was at first indecisive if I should be a candidate for the doctoral program at his Ergonomics Unit (EU). I was dressed in my formal traditional Malay costume, unlike the rest of the delegates who were casual. Many thoughts must have gone through his mind as he scrutinised me. It all changed dramatically when he heard me talk for the first time. I responded confidently to his line of questioning over my previous MSc work on central task complexity and peripheral vision.

My early days at UCL began with a series of interviews by Andy Whitefield, Andrew Life, and Dan Diaper. I asked them what it was like to work with John. They smiled and I understood that it was tough but rewarding.

Today, I am living proof of John Long’s rigorous and impactful training. The PhD program was specially designed to impart knowledge and skills as well as shared values and experiences. His style puts him apart from those I had trained with earlier. He presented no answers to my work but only questions and more questions. This helped me to develop an inquiring and reflective approach; also to think out of the box. At times his high workload distanced him from the supervisory role. But in turn I became groomed to be self-reliant, directed, and focused.

The PhD candidates were an integral part of the EU family. We attended monthly meetings to deliver progress report, and to be assigned tasks on rotational basis so as to develop multi-tasking skills. The tasks enriched our experiences in communication, organization, and documentation, which became useful and valuable when we embarked on our career. The requirement to follow some of the exciting MSc site visits enhanced our problem-solution skills, such as visits to the London underground, coal mine, hospital, London Design Council, to name but a few.

While I do not consume alcohol, the numerous pub crawls on Fridays, exposed me to the British way of life, and more importantly, to get to know the growing ‘family’ as the Unit accepted more graduate students. John and his beloved late wife, Doris, also hosted several alumni gatherings at his beautiful home in Muswell Hill. The concept of networking and social programming emerged from his purposeful convictions.

Despite the challenging and stressful environment of London and UCL, I completed my training within the three year timeline to accomplish my dream as the first foreign PhD student at EU. The greatest achievement was to obtain my PhD in Cognitive Ergonomics from the University College London, and to be supervised by Professor John Long and Dr. Andy Whitefield. I am proud to have them as my mentors.

I owe my successes today to John Long’s vision and dedication that crafted a future of curiosity and motivation for HCI/Cognitive Ergonomics research. The training program that I graduated from was a benchmark for quality work.

I wish John soul-searching happiness and continued good health, and the evolved UCL Interaction Centre a stimulating future.

 

Halimahtun Mohd Khalid, PhD, CPE

1986-1989

3.1 General Conception of HCI Design Knowledge 150 150 John

3.1 General Conception of HCI Design Knowledge

The HCI Design Knowledge Conception pre-supposes an associated HCI Discipline having three primary characteristics: a general problem; practices, providing solutions to that problem; and knowledge supporting those practices. (C5) The general HCI problem is: to design people’s use of computers to do something as wanted. (F1) The HCI Conception, then, is unequivocally one of knowledge and its support for design. (C1)

HCI design knowledge is the product of research and practice, both of which solve HCI design problems. (F2) (C2) Such knowledge may be private or public, formal or informal. It may assume a number of forms, for example, codified; experienced; proceeduralised; demonstrated; exemplified as in skills; theories; guidelines; heuristics; rules-of-thumb; principles; hints-and-tips etc.  (C3)(C4) HCI design knowledge may be maintained in a number of ways: for example, it may be expressed in journals; example solutions to design problems; learning systems; communities; good practice; procedures; word-of-mouth; tools etc.  HCI knowledge is, therefore, a necessary characteristic of the HCI discipline, its practices and its design problem. (F3)

This wide range of HCI design knowledge is matched by an equally wide range of HCI design practices seeking, specifying and implementing solutions to the HCI design problem. Such design practices include: ‘specify-then- implement’ (specification precedes implementation); ‘specify-and-implement’ (specification and implementation proceed together); ‘implement-and-test’ (implementation occurs without specification, as in ‘trial and error’ and ‘implement and iterate’). In addition, all of these practices may include iteration and test in a variety of different ways. (F4) (C6) (C7)

Key concepts are shown in bold on their first appearance only.

Footnotes and Citations

Footnotes

(F1) This definition encapsulates the basic characteristics of HCI: 1. that people not only use computers; but use them to do something (whatever that something may be); 2. That people not only use computers to do something; but to do something what and how they want.

(F2) HCI research solves design problems to acquire and to validate HCI design knowledge. HCI practice solves design problems to satisfy user and client requirements.

(F3) Some semblance of order can be brought to this plethora of types of design knowledge by supposing different approaches to establishing a discipline of HCI, for example: Craft; Applied Science; and Engineering (Long and Dowell, 1989).

(F4) Some semblance of order can be brought to this plethora of types of design practice by supposing different approaches to establishing a discipline of HCI, for example: Craft; Applied Science; and Engineering (Long and Dowell, 1989). See also F3 above.

Citations

Long and Dowell (1989)

(C1) ‘Second, the scope of the general problem of HCI is defined by reference to humans, computers, and the work they perform.’ (Page 9, Abstract, Lines 7-9) (

C2) ‘The framework expresses the essential characteristics of the HCI discipline, and can be summarised as: ‘the use of HCI knowledge to support practices seeking solutions to the general problem of HCI’. (Page 9, Lines 16-19)

(C3) ‘…….. Some would claim HCI theory as explanatory laws, others as design principles. Some would claim HCI theory as directly supporting HCI practice, others as indirectly providing support. Some would claim HCI theory as effectively supporting HCI practice, whilst others may claim such support as non-existent.’ (Page 10, Lines 12-17)

(C4) ‘All definitions of disciplines make reference to discipline knowledge as the product of research or more generally of a field of study. Knowledge can be public (ultimately formal) or private (ultimately experiential). It may assume a number of forms; for example, it may be tacit, formal, experiential, codified – as in theories, laws and principles etc. It may also be maintained in a number of ways; for example, it may be expressed in journals, or learning systems, or it may only be embodied in procedures and tools. All disciplines would appear to have knowledge as a component (for example, scientific discipline knowledge, engineering discipline knowledge, medical discipline knowledge, etc). Knowledge, therefore, is a necessary characteristic of a discipline.’ (Page 11, Lines 30-38)

Dowell and Long (1989)

(C5) ‘Most definitions of disciplines assume three primary characteristics: a general problem; practices, providing solutions to that problem; and knowledge, supporting those practices.’ (Page 1514, Lines 43-45)

(C6) ‘These four deficiencies are endemic to the craft nature of contemporary HF practice. They indict the tacit HF discipline knowledge consisting of accumulated experience embodied in procedures, even where that experience has been influenced by guidance offered by the science of psychology. Because the knowledge is tacit (i.e., implicit or informal), it cannot be operationalised, and hence the role of HF in systems development cannot be planned as would be necessary for the proper integration of the knowledge. Without being operationalised, its knowledge cannot be tested, and so the efficacy of the practices it supports cannot be guaranteed. Without being tested, its knowledge cannot be generalised for new applications and so the practices it can support will be inefficient. Without being operationalised, testable, and general, the knowledge cannot be developed in any structured way’ (Page 1517, Lines 3-13)

(C7) ‘The contemporary HF discipline does not possess either methodological or substantive engineering principles. The heuristics it possesses are either ‘rules of thumb’ derived from experience or guidelines derived from psychological theories and findings. Neither guidelines nor rules of thumb offer assurance of their efficacy in any given instance, and particularly with regard to the effectiveness of a design. The methods and models of HF (as opposed to methodological and substantive principles) are similarly without such an assurance. (Page 1520, Lines 21-28)

3.2 General Conception of HCI Engineering Design Knowledge 150 150 John

3.2 General Conception of HCI Engineering Design Knowledge

The General Conception pre-supposes an associated HCI Engineering Discipline (F1) comprising: HCI Engineering knowledge, which distinguishes the interactive system of user and computer, the tasks it performs as desired and the goodness of that performance in terms of specific criteria (C1) The knowledge supports HCI Engineering practices seeking to solve design problems. Design problems here include specification, followed by implementation, of users interacting with computers (the interactive system) to perform tasks as desired in some domain of application. (C3)

The HCI Engineering Conception, then, is unequivocally one of design knowledge. (F2) HCI Engineering knowledge is the product of research. Such knowledge is public and ultimately formal. (F3) It may assume a number of forms, for example, codified, proceduralised, formal etc, as in theories, principles etc. It may be maintained in a number of ways; for example, it may be expressed in journals, learning systems, procedures, tools etc. HCI Engineering knowledge is, therefore, a necessary characteristic of the HCI Engineering Discipline. (C2)

The discipline of HCI Engineering, aims (in the longer term) to solve its general problem of design by the specification of designs before their implementation – as in ‘specify then implement’ design practices. (C6) (C7) (C9) The latter is made possible by the prescriptive nature of the knowledge supporting such practices – knowledge formulated as HCI Engineering principles. (C4) However, a pre-requisite for the formulation of any HCI Engineering principles is a Conception. The EU Conception, from which the HCI Engineering Conception is generalised, is a unitary view of the HCI Engineering design problem; its power lies in the coherence and completeness of its definition of the concepts, which can express that problem. (F4) (C8) (C12)

Engineering principles are articulated in terms of those self-same concepts. The latter include: user; computer; interaction; task; domain of application; system; and performance (for a full listing – see 2.2). Thus, the Conception of HCI Engineering principles assumes the possibility of a codified, general, and testable formulation of HCI Engineering discipline knowledge. The latter might be prescriptively applied to designing humans and computers interacting to perform tasks as desired. Such principles would be unequivocally formal and operational. Indeed, their operational capability would derive directly from the formality of their concepts. (C4) HCI Engineering concepts would be generalisable over classes of design problem solutions. Since the principles are operational, their application (expressed as design solutions) would necessarily be specifiable. They would also be testable and so their reliability and generality could also be specified. (C5)

In this way would the principles, expressed in terms of the Conception of Engineering design knowledge, be validated. Such validated Engineering design principles would offer a better guarantee (that is, more assurance – see 3.6.1)) of solving the HCI general design problem. Better, for example, than the experiential trial-and-error knowledge of craft HCI or the guidelines/heuristics of Applied Science HCI. (C11) HCI Engineering principles, following the Conception of Engineering design knowledge, can be substantive or methodological. Methodological principles prescribe the methods for solving the general HCI design problem. Methodological principles would assure complete specification of all necessary levels of design solution representation. Substantive principles prescribe the features and properties of HCI systems that constitute solutions to the HCI Engineering design problem. (C10)

The extent, to which HCI engineering principles might be realiseable in practice, in the longer term, remains to be seen and demonstrated. In the meantime, craft knowledge (F5) in whatever form – models, methods, heuristics, guidelines, experience, procedures etc cannot be other than recruited to solve HCI design problems both by researchers and practitioners. (C13)

Key concepts are shown in bold on their first appearance only.

Footnotes and Citations

Footnotes

(F1) The contrast here with Engineering is Science, which has its own discipline problem, knowledge and practices.

(F2) See (F1)

(F3) For the present purposes, Engineering, in its early craft stages, is not addressed.

(F4) Other HCI Engineering conceptions, other than that of the EU, might, of course, also be postulated.

(F5) See (F3)

Citations

Long and Dowell (1989)

(C1) ‘The framework expresses the essential characteristics of the HCI discipline, and can be summarised as: ‘the use of HCI knowledge to support practices seeking solutions to the general problem of HCI’. (Page 9, Lines 16-19)

(C2) ‘All definitions of disciplines make reference to discipline knowledge as the product of research or more generally of a field of study. Knowledge can be public (ultimately formal) or private (ultimately experiential). It may assume a number of forms; for example, it may be tacit, formal, experiential, codified – as in theories, laws and principles etc. It may also be maintained in a number of ways; for example, it may be expressed in journals, or learning systems, or it may only be embodied in procedures and tools. All disciplines would appear to have knowledge as a component (for example, scientific discipline knowledge, engineering discipline knowledge, medical discipline knowledge, etc). Knowledge, therefore, is a necessary characteristic of a discipline.’ (Page 11, Lines 30-38)

(C3) ‘The discipline of engineering may characteristically solve its general problem (of design) by the specification of designs before their implementation. It is able to do so because of the prescriptive nature of its discipline knowledge supporting those practices – knowledge formulated as engineering principles.’ (Page 24, Lines 11-14)

(C4) ‘The conception of HCI engineering principles assumes the possibility of a codified, general and testable formulation of HCI discipline knowledge which might be prescriptively applied to designing humans and computers interacting to perform work effectively. Such principles would be unequivocally formal and operational. Indeed their operational capability would derive directly from their formality, including the formality of their concepts.’ (Page 24, Lines 28-31)

(C5) ‘First, HCI engineering principles would be a generaliseable knowledge. …….. Second, engineering HCI principles would be operational, and so their application would be specifiable…….. Because they would be operational, they would be testable and their reliability and generality could be specified.’ (Page 27, Lines 20-22 and 36-28)

Dowell and Long (1989)

(C6) ‘The paper .….. examines the potential for Human Factors to formulate engineering principles. ……… A conception would provide the set of related concepts which both expressed the general design problem more formally, and which might be embodied in engineering principles.’ (Page 1513, Lines 9 and 10)

(C7) By comparing the HF general design problem with other, better-understood, general design problems, and by identifying the formal knowledge possessed by the corresponding disciplines, the potential for HF engineering principles is suggested.’ (Page 1514, Lines 15-18).

(C8) ‘However, a pre-requisite for the formulation of any engineering principle is a conception. A conception is a unitary (and consensus) view of a general design problem; its power lies in the coherence and completeness of its definition of the concepts, which can express that problem. Engineering principles are articulated in terms of those concepts.’ (Page 1514, Lines 23-27)

(C9) ‘Generally, the established engineering disciplines possess formal knowledge: a corpus of operationalised, tested, and generalised principles. Those principles are prescriptive, enabling the complete specification of design solutions before those designs are implemented (see Dowell and Long, 1988b).’ (Page 1520, Lines 1-5)

(C10) ‘Engineering principles can be substantive or methodological. Methodological Principles prescribe the methods for solving a general design problem optimally. ……Methodological principles would assure each lower level of specification as being a complete representation of an immediately higher level. Substantive Principles prescribe the features and properties of artefacts, or systems that will constitute an optimal solution to a general design problem. (Page 1520, Lines 6-15)

(C11) ‘The contemporary HF discipline does not possess either methodological or substantive engineering principles. The heuristics it possesses are either ‘rules of thumb’ derived from experience or guidelines derived from psychological theories and findings. Neither guidelines nor rules of thumb offer assurance of their efficacy in any given instance, and particularly with regard to the effectiveness of a design. The methods and models of HF (as opposed to methodological and substantive principles) are similarly without such an assurance. (Page 1520, Lines 21-28)

(C12) ‘Such a conception ….. enables the formulation of engineering principles which embody and instantiate those concepts.( Page 1520, Line 1)

(C13) ‘The extent to which HF engineering principles might be realiseable in practice remains to be seen. It is not supposed that the development of effective systems will never require craft skills in some form, and engineering principles are not seen to be incompatible with craft knowledge, particularly with respect to their instantiation. At a minimum, engineering principles might be expected to augment the craft knowledge of HF professionals. Yet the great potential of HF engineering principles for the effectiveness of the discipline demands serious consideration.’ (Page 1533, Lines 24-29)

3.3 HCI/E(U) Conception of HCI Engineering Design Knowledge 150 150 John

3.3 HCI/E(U) Conception of HCI Engineering Design Knowledge

The HCI/E(U) Conception of HCI Engineering Design Knowledge presupposes an associated HCI Engineering Discipline, comprising: HCI engineering knowledge, which distinguishes the interactive system of user and computer, the work it performs and the effectiveness of that performance, in terms of task quality and system resource costs. This HCI design knowledge supports HCI practices seeking to diagnose design problems and to prescribe design solutions to those problems. (C18)

The EU Conception of the HCI Engineering design problem is informally expressed as: to design human interactions with computers for effective working. The EU Conception, then, is unequivocally one of design knowledge. HCI Engineering knowledge, following the EU Conception, is the product of research. Such knowledge is public and ultimately formal. It may assume a number of forms, for example, codified, proceduralised, formal etc, as in theories, principles etc. It may be maintained in a number of ways, for example, it may be expressed in journals, learning systems, procedures, tools etc. HCI Engineering knowledge is, therefore, a necessary characteristic of the EU HCI Engineering Discipline. (C3)

The discipline of HCI Engineering, aims, following the EU Conception, (in the longer term (F1)) to solve its general problem of design by the specification of designs before their implementation – as in ‘specify then implement’ design practices. (C12) (C19) The latter is made possible by the prescriptive nature of the knowledge supporting such practices – knowledge formulated as HCI Engineering principles. (C21)

However, a pre-requisite for the formulation of any HCI Engineering principles is a Conception. The EU Conception is a unitary view of the HCI Engineering design problem; its power lies in the coherence and completeness of its definition of the concepts, which can express that problem. (C17) Engineering principles are articulated in terms of those self-same concepts. The latter include: user; computer; interaction; work; work domain; worksystem; effectiveness; performance; task quality; system resource costs etc (see 2.5 for a complete presentation of the EU design problem concepts, which would be recruited to the formulation of EU-conceived engineering principles. (C16) (C17) (F2)

Thus, the EU Conception of HCI Engineering principles assumes the possibility of a codified, general, and testable formulation of HCI Engineering discipline knowledge. The latter might be prescriptively applied to designing humans and computers interacting to perform work effectively. Such principles would be unequivocally formal and operational. Indeed, their operational capability would derive directly from the formality of their concepts. (C13) EU HCI Engineering concepts would be generalisable over classes of design problem solutions. Since the principles are operational, their application (expressed as design solutions) would necessarily be specifiable. They would also be testable and so their reliability and generality could also be specified. (C14)

In this way would the principles, expressed in terms of the EU Conception of Engineering design knowledge, be validated. Such validated Engineering design principles would offer a better guarantee (that is, more assurance) of solving the HCI general design problem. Better, for example, than the experiential trial-and-error knowledge of craft HCI (C4) (C5) (C6) or the guidelines/heuristics of Applied Science HCI (C7) (C8) (C9) (C10) (C11) (C15) (F3) HCI Engineering principles, following the EU Conception of Engineering design knowledge, can be substantive or methodological. Methodological principles prescribe the methods for solving the general HCI design problem. Methodological principles would assure complete specification of all necessary levels of design solution representation. Substantive principles prescribe the features and properties of HCI systems that constitute solutions to the EU HCI Engineering design problem. (C20)

The extent, to which HCI engineering principles might be realisable in practice, in the longer term, remains to be seen and demonstrated. In the meantime, craft knowledge in whatever form – models, methods, heuristics, guidelines, experience, procedures etc cannot be other than be recruited to solve HCI design problems both by researchers and practitioners (C22) (F4)

Key concepts are shown in bold on their first appearance only.

Footnotes and Citations

Footnotes

 (F1) In the shorter term, to solve HCI design problems, either for research or for practice, any type of knowledge might be used.
(F2) Or indeed to other types of Engineering knowledge, for example, models and methods, intended to support the diagnosis of design problems and the prescription of their design solutions.
(F3) Craft HCI would also include craft engineering HCI – see also (F1) and (F2).
(F4) See also (F1), (F2) and (F3).
Citations
Long and Dowell (1989)

(C1) ‘The framework expresses the essential characteristics of the HCI discipline, and can be summarised as: ‘the use of HCI knowledge to support practices seeking solutions to the general problem of HCI’. (Page 9, Lines 16-19)

(C2) ‘ Some would claim HCI theory as explanatory laws, others as design principles. Some would claim HCI theory as directly supporting HCI practice, others as indirectly providing support. Some would claim HCI theory as effectively supporting HCI practice, whilst others may claim such support as non-existent.’ (Page 10, Lines 12-17)

(C3) ‘All definitions of disciplines make reference to discipline knowledge as the product of research or more generally of a field of study. Knowledge can be public (ultimately formal) or private (ultimately experiential). It may assume a number of forms; for example, it may be tacit, formal, experiential, codified – as in theories, laws and principles etc. It may also be maintained in a number of ways; for example, it may be expressed in journals, or learning systems, or it may only be embodied in procedures and tools. All disciplines would appear to have knowledge as a component (for example, scientific discipline knowledge, engineering discipline knowledge, medical discipline knowledge, etc). Knowledge, therefore, is a necessary characteristic of a discipline.’ (Page 11, Lines 30-38)

(C4) ‘Craft disciplines solve the general problems they address by practices of implementation and evaluation. Their practices are supported by knowledge typically in the form of heuristics; heuristics are implicit (as in the procedures of good practice) and informal (as in the advice provided by one craftsperson to another). Craft knowledge is acquired by practice and example, and so is experiential; it is neither explicit nor formal.’ (Page 16, Lines 4-8)

(C5) ‘…….. the (public) knowledge possessed by HCI as a craft discipline is not operational. That is to say, because it is either implicit or informal, it cannot be directly applied by those who are not associated with the generation of the heuristics or exposed to their use. If the heuristics are implicit in practice, they can be applied by others only by means of example practice. If the heuristics are informal, they can be applied only with the help of guidance from a successful practitioner (or by additional, but unvalidated, reasoning by the user).’ (Page 18, Lines 28-33)

(C6) ‘If craft knowledge is not testable, then neither is it likely to be generalisable ……To be clear, if being operational demands that (public) discipline knowledge can be directly applied by others than those who generated the knowledge, then being general demands that the knowledge be guaranteed to be appropriate in instances other than those in which it was generated. Yet, the knowledge possessed by HCI as a craft discipline applies only to those problems already addressed by its practice, that is, in the instances, in which it was generated.’ (Page 19, Lines 11 and 15-20)

(C7) ‘The discipline of science uses scientific knowledge (in the form of theories, models, laws, truth propositions, hypotheses, etc.) to support the scientific practice ……..Scientific knowledge is explicit and formal, operational, testable and generalisable. It is therefore refutable (if not proveable, Popper [1959])’. (Page 20, Lines 2-3 and 7-9)

(C8) ‘An applied science discipline is one which recruits scientific knowledge to the practice of solving its general problem – a design problem.’ (Page 20, Lines 16 and 17)

(C9) ‘ First, its science knowledge cannot be applied directly, not – as in the case of craft knowledge – because it is implicit or informal, but because the knowledge is not prescriptive; it is only explanatory and predictive. Its scope is not that of the general problem of design.’ (Page 23, Lines 20-23)

(C10) ‘Second, the guidelines based on the science knowledge, which are not predictive but prescriptive, are not defined, operationalised, tested or generalised with respect to desired effective performance. Their selection and application in any system would be a matter of heuristics (and so paradoxically of good practice).’ (Page 23, Lines 25-28)

(C11) ‘Science knowledge is explicit and formal, and so supports reasoning about the derivation of guidelines, their solution and application (although one might have to be a discipline specialist so to do).’ (Page 23, Lines 36-38)

(C12) ‘The discipline of engineering may characteristically solve its general problem (of design) by the specification of designs before their implementation. It is able to do so because of the prescriptive nature of its discipline knowledge supporting those practices – knowledge formulated as engineering principles.’ (Page 24, Lines 11-14)

(C13) ‘The conception of HCI engineering principles assumes the possibility of a codified, general and testable formulation of HCI discipline knowledge which might be prescriptively applied to designing humans and computers interacting to perform work effectively. Such principles would be unequivocally formal and operational. Indeed their operational capability would derive directly from their formality, including the formality of their concepts.’ (Page 24, Lines 28-31)

(C14) ‘First, HCI engineering principles would be a generaliseable knowledge. …….. Second, engineering HCI principles would be operational, and so their application would be specifiable…….. Because they would be operational, they would be testable and their reliability and generality could be specified.’ (Page 27, Lines 20-22 and 36-28)

(C15) ‘ Although all three conceptions address the general problem of HCI, they differ concerning the knowledge recruited to solve the problem. Craft recruits heuristics; applied science recruits theories expressed as guidelines; and engineering recruits principles.’ (Page 28, Lines 22-24)

Dowell and Long (1989)

(C16) ‘The paper ….. examines the potential for Human Factors to formulate engineering principles. ……… A conception would provide the set of related concepts which both expressed the general design problem more formally, and which might be embodied in engineering principles.’ (Page 1513, Lines 9 and 10)

(C17) ‘However, a pre-requisite for the formulation of any engineering principle is a conception. A conception is a unitary (and consensus) view of a general design problem; its power lies in the coherence and completeness of its definition of the concepts, which can express that problem. Engineering principles are articulated in terms of those concepts.’ (Page 1514, Lines 23-27)

(C18) ‘Most definitions of disciplines assume three primary characteristics: a general problem; practices, providing solutions to that problem; and knowledge, supporting those practices.’ (Page 1514, Lines 43-45)

(C19) ‘Generally, the established engineering disciplines possess formal knowledge: a corpus of operationalised, tested, and generalised principles. Those principles are prescriptive, enabling the complete specification of design solutions before those designs are implemented (see Dowell and Long, 1988b). This theme of prescription in design is central to the thesis offered here.’ (Page 1520, Lines 1-5)

(C20) ‘Engineering principles can be substantive or methodological. Methodological Principles prescribe the methods for solving a general design problem optimally. ….. Methodological principles would assure each lower level of specification as being a complete representation of an immediately higher level. Substantive Principles prescribe the features and properties of artefacts, or systems that will constitute an optimal solution to a general design problem. (Page 1520, Lines 6-15)

(C21) ‘Such a conception ….. enables the formulation of engineering principles which embody and instantiate those concepts. ( Page 1520, Line 46 and Page 1521, Line 1)

(C22) ‘The extent to which HF engineering principles might be realiseable in practice remains to be seen. It is not supposed that the development of effective systems will never require craft skills in some form, and engineering principles are not seen to be incompatible with craft knowledge, particularly with respect to their instantiation. At a minimum, engineering principles might be expected to augment the craft knowledge of HF professionals. Yet the great potential of HF engineering principles for the effectiveness of the discipline demands serious consideration.’ (Page 1533, Lines 24-29)

 

1.1 General Conception of HCI Discipline 150 150 John

1.1 General Conception of HCI Discipline

The General Conception of the HCI Discipline  is generalised from the General Conception of the HCI Engineering Discipline . The General Conception comprises HCI knowledge, which  takes a variety of forms , distinguishing the interactive system of people  and computers, what it does and how well it does it.  The knowledge supports HCI practices of design and implementation of people using  computers to do something as wanted. This Conception is general  to any approach to HCI.

 

Key Concepts, Footnotes and Citations

The General Conception (F1) of the HCI Discipline (C1) is generalised from the General Conception of the HCI Engineering Discipline (1.2). The General Conception comprises HCI knowledge, which  takes a variety of forms (F2), distinguishing the interactive system of people  and computers, what it does and how well it does it. (C2) The knowledge supports HCI practices of design (F3) and implementation of people using  computers to do something as wanted. (C3) This Conception is general  to any approach to HCI.

Key concepts are shown in bold on their first appearance only.

Footnotes

(F1) ‘Conception’ is preferred here, as it clearly implies a set of linked concepts, which is what a conception is. However, within HCI more generally , ‘Framework’ would do as well.  Some might even prefer ‘Model’ or most generally ‘Approach’.

(F2) Such forms of knowledge include: guidelines; models; methods; heuristics etc.

(F3) Design here includes evaluation.

Citations

 Long and Dowell (1989)

(C1) ‘The framework expresses the essential characteristics of the HCI discipline and can be summarised as ‘ the use of HCI knowledge to support practices seeking solutions to the general problem of HCI’. (Page 9, Abstract, Lines 11-14)

(C2) ‘Second, the scope of the general problem of HCI is defined by reference to humans, computers, and the work they perform.’ (Page 9, Abstract, Lines 7-9)

(C3) ‘Most definitions assume three primary characteristics of disciplines: knowledge; practice; and a general problem.’ (Page 11, Lines 26 and 27)

1.2 General Conception of HCI Engineering Discipline 150 150 John

1.2 General Conception of HCI Engineering Discipline

The General Conception of the HCI Engineering Discipline is generalised from the HCI/E Conception . The General Conception comprises HCI Engineering Knowledge, which distinguishes the interactive system of user and computer, the tasks it performs as desired and the goodness of that performance in terms of specific criteria.  The knowledge supports Practices, seeking to solve design problems.  Design here includes specification, followed by implementation and evaluation of users interacting with computers (the interactive system), to perform tasks as desired in some domain of application.

Key Concepts, Footnotes and Citations

The General Conception of the HCI Engineering Discipline is generalised from the HCI/E Conception (1.3). The General Conception comprises HCI Engineering Knowledge, which distinguishes the interactive system of user and computer, the tasks (F1) it performs as desired and the goodness of that performance in terms of specific criteria. (F2) (C1)  The knowledge supports HCI Engineering Practices, seeking to solve design problems. (C2) Design here includes specification, followed by implementation, of users interacting with computers ( the interactive system), to perform tasks as desired in some domain of application. (C3)

Key concepts are shown in bold on their first appearance only.

Footnotes

(F1) Task here is to be interpreted widely, as anything a user can do with a computer, either desired or undesired, well or badly.

(F2 ) Criteria, here, may include: time; errors; completeness etc.

Citations

Long and Dowell (1989)

(C1) ‘It (the Conception) dichotomises ‘interactive worksystems’ which perform work, and ‘domains of application’ in which work originates, is performed, and has its consequences’. (Page 24, Lines 39 and 40)

(C2) ‘The discipline of engineering includes the engineering practice addressing the general (engineering) problem of design.’  (Page 12, Lines 3-5)

(C3) ‘The discipline of engineering may characteristically solve its general problem (of design) by the specification of designs before their implementation.’ (Page 24, Lines 11-12).

 

1.3 HCI/E Conception of HCI Engineering Discipline: a Summary 150 150 John

1.3 HCI/E Conception of HCI Engineering Discipline: a Summary

The HCI/E Conception of HCI as an Engineering discipline is a summary of the complete version (1.4 and 1.5).

The Conception comprises: HCI Engineering Knowledge as Principles, which distinguish the interactive worksystem, of user and computer, the work it performs and the effectiveness of that performance in terms of task quality and system resource costs. These Principles support HCI Engineering Practices seeking to diagnose design problems and to prescribe design solutions to those problems. Design here is characterised as ‘specify then implement’ designs of users interacting with computers (the interactive worksystem) to perform effective work in some domain of application.

Key concepts, Footnotes and Citations

The HCI/E Conception of the HCI Engineering Discipline comprises (C2): HCI Knowledge as Principles (F1), which distinguish the interactive worksystem, of user and computer, the work it performs and the effectiveness of that performance in terms of task quality and system resource costs. (C3) These Principles support HCI Practices seeking to diagnose design problems and to prescribe design solutions to those problems. (F2) (C1) Design here is characterised as ‘specify then implement’ designs of users interacting with computers (the interactive worksystem) to perform effective work in some domain of application. (F3) (C4)

Key concepts are shown in bold on their first appearance only.

 Footnotes

 (F1) No such Principles exist in the current research and practice of HCI. The HCI/E Conception and frameworks are intended to form the basis, on which such Principles might be constructed in the longer term. A start, however, has been made (Stork (1999) and Cummaford (2007). In the meantime, HCI/E research and practice recruits whatever HCI knowledge is available at present to solve design problems.

(F2) According to the HCI/E Conception, design problems have to be diagnosed (and specified) before they can be solved (and implemented).

(F3) The current absence of HCI Engineering Design Principles, requiring the use of different types of HCI knowledge – see (F1) above –   also requires, in the meantime,  they support different types of practice, for example, ‘trial-and- error; ‘specify and implement’; ‘prototype and test’ etc.

Citations

 Long and Dowell (1989)

(C1) ‘The  (discipline) framework expresses the essential characteristics of the HCI discipline, and can be summarised as: ‘the use of HCI knowledge to support practices seeking solutions to the general problem of HCI’.’ (Page 9, Lines 16-19).

(C2) ‘Two prerequisites of a framework for conceptions of the HCI discipline are assumed. The first is a definition of disciplines appropriate for the expression of HCI. The second is a definition of the province of concern of the HCI discipline which, whilst broad enough to include all disparate aspects, enables the discipline’s boundaries to be identified.’ (Page 11, Lines 18-21).

(C4) ‘The discipline of engineering may characteristically solve its general problem (of design) by the specification of designs before their implementation. It is able to do so because of the prescriptive nature of its discipline knowledge supporting those practices – knowledge formulated as engineering principles.’ (Page 24, Lines 11-14)

Dowell and Long (1989)

(C3) ‘Taken together, the dimension of problem hardness, characterising general design problems, and the dimension of specification completeness, characterising discipline practices, constitute a classification space for design disciplines……..’ (Page 1518, Lines 20-22)

 

1.6 Discipline; Engineering; and Human-Computer Interaction 150 150 John

1.6 Discipline; Engineering; and Human-Computer Interaction

1.6.1 Discipline

The general concept of a discipline (F1) comprises: discipline knowledge (C3); practices (C4); and a general problem (C5), having a particular scope.(F2) (C1) (C2) The knowledge supports practices, seeking solutions to the general discipline problem, expressed in terms of its particular scope. (C6) (C7)

Footnotes and Citations

Footnotes

(F1) A discipline here is to be distinguished from the community, which practises it.

(F2) The scope of a problem is the domain or range over which it operates.

Citations

Long and Dowell (1989)

(C1) ‘First, consideration of disciplines in general suggests their complete definition can be summarised as: ‘knowledge, practices and a general problem having a particular scope, where knowledge supports practices seeking solutions to the general problem’.’ (Page 9, Lines 9-14)

(C2) ‘Most definitions assume three primary characteristics of disciplines: knowledge; practice; and a general problem.’ (Page 11, Lines 27 and 28)

(C3) ‘All definitions of disciplines make reference to discipline knowledge as the product of research or more generally of a field of study……. Knowledge, therefore, is a necessary characteristic of a discipline.’ (Page 11, Lines 29 and 30)

(C4) ‘Consideration of different disciplines suggests that practice is also a necessary characteristic of a discipline.’ (Page 11, Line 38 and Page 12, Line 1)

(C5) ‘Further, a discipline’s knowledge is used by its practices to solve a general (discipline) problem……’ (Page 12, Lines 1 and 2)

(C6) ‘Clearly, disciplines are here being distinguished by the general (discipline) problem they address.’ (Page 12, Lines 8 and 9)

(C7) ‘Taken together, the three necessary characteristics of a discipline (and the two basic properties additionally concluded), suggest the definition of a discipline as: ‘the use of knowledge to support practices seeking solutions to a general problem having a particular scope’.’  (Page 12, Lines 26-32)

1.6.2 Engineering

The general concept of a discipline of Engineering (F1) comprises: engineering knowledge, as principles (F2) (C2); their application to practices, seeking the diagnosis of, and the solution to, the general engineering problem of the design of particular systems or artefacts. (C1) This concept holds for any engineering approach to a discipline of HCI.

Footnotes and Citations

Footnotes

(F1) Engineering here is to be contrasted, for example, with Science.

(F2) Although Principles are critical to engineering knowledge, in contrast to other disciplines, it comprises a wide range of different types of knowledge – models; methods; etc.

Citations

Long and Dowell (1989)

(C1)’The discipline of engineering includes the engineering practice addressing the general (engineering) problem of design.’  (Page 12, Lines 3-5)

(C2) ‘The discipline of engineering may characteristically solve its general problem (of design) by the specification of designs before their implementation. It is able to do so because of the prescriptive nature of its discipline knowledge supporting those practices – knowledge formulated as engineering principles.’ (Page 24, Lines 11-14)

 

1.6.3 Human-Computer Interaction

The general concept of a discipline of HCI (C2) comprises: HCI knowledge; its application to practices, seeking solution to the general HCI problem (C4) of design, having the particular scope of people using (F1) computers to do something (F2) as wanted. (F3) (C1) (C3)

Footnotes and Citations

Footnotes

(F1) ‘Using’ here contrasts with simply ‘interacting.

(F2) ‘Something’ here is intentionally very general. The contrast is, again, with simply ‘interacting’ – see (F1).

(F3) ‘As wanted’ by, for example, the user; the client; the users’ organisation; or indeed all of them (and more).

Citations

Long and Dowell (1989)

(C1) ‘The  (discipline) framework expresses the essential characteristics of the HCI discipline, and can be summarised as: ‘the use of HCI knowledge to support practices seeking solutions to the general problem of HCI’.’ (Page 9, Lines 16-19).

(C2) ‘HCI concerns humans and computers interacting to perform work.’ (Page 13, Line 1)

(C3) ‘Taken together, these implications suggest a definition of the scope of the general (discipline) problem of HCI. It is expressed, in summary, as ‘humans and computers interacting to perform work effectively’.’ ( Page 13, Lines 10-12). (C4) … the general problem addressed by the discipline of HCI is asserted as: ‘the design of humans and computers interacting to perform work effectively’.  (Page 13, lines 19-21).