2.1 General Conception of HCI Design Problem

 The General Conception of the HCI design problem is expressed as: ‘to design people’s use of computers to do something as wanted.’ (C1) (C2) The General Conception of the HCI design problem presupposes an associated HCI Discipline having three primary characteristics: a general problem; practices providing solutions to that problem; and knowledge supporting those practices. (C3) The Conception belongs to the class of general design problem. (C4)

The General Conception has the necessary property of a scope, delimiting the province of concern of the associated discipline of HCI. (C5) The scope includes: people, both as individuals, groups and as social organisations. It also includes computers, both as programmable machines, stand-alone and networked, and as functionally embedded devices within machines. Its scope also includes: the use of computers as wanted, both as concerns individuals and the organisations in which it occurs. (C6) (F1)

The Conception categorises HCI design problems as ‘easy’ or ‘difficult’. Easy and difficult problems are distinguished by the need for design solutions (as specified by HCI design practices) to be determinate. The design practices vary in the completeness of their specification before implementation. (C7) ‘Specify then implement’ design practices implicate more complete specification. ‘Implement and test’ design practices implicate less complete specification. (F2) Taken together, the dimension of problem difficulty, characterising HCI general design problems and the dimension of specification completeness, characterising HCI practices, constitute a classification space for all approaches to HCI.

The General Conception of the HCI design problem asserts a basic distinction between people-computer systems, which do things as wanted and a world in which these things originate, are done and have their consequences. (C10) ‘As wanted’ relates to the relationship of an interactive system with its use, assimilating both whether things are done, as wanted and the effort required for that doing. (F3)  The concern of the associated HCI discipline is to design the interactive system to do things, as wanted. The interactive system consists of people using computers and computers being used. According to the Conception, the general problem of HCI is to produce designs of people, which, interacting with computers, do something, as wanted. (C9)

The interactions take place in a world in which computers are used to do things, which change that world in some way. (C10) Computer use by people arises at the intersection of organisations and computer technology. Conceptualisation thereof may be both abstract and physical.  The abstract conceptualisation includes information and knowledge. The physical conceptualisation includes things. Computer use produces changes in the world over time. Following the General Conception, organisations have domains as their operational scope and require the changes brought about by computer use. It is a requirement satisfied by people using computers as wanted. (C11) An HCI design problem exists, when actual computer use is not as wanted.

The General Conception identifies interactive systems, consisting of people and computers doing something as wanted. (C14) People formulate goals which are intentional (or purposeful). Computers are designed to achieve goals and are said to be intended (or purposive).  Computer use is distinguished by a boundary, enclosing all people and computers, whose purpose is to achieve a common goal. (C13) Interactive systems achieve goals by doing something as wanted, that is, by producing change.

People and computers are conceptualised as sub-systems, which interact. (C14) Interaction may be loosely understood as ‘what the person and computer do’ in contrast with ‘what is done’, that is, the changes effected in the domain of application. In the General Conception, interactions are both physical and abstract. (C15) The latter process information. (C17) In the General Conception of the HCI design problem, doing things as wanted derives from the relationship of an interactive system with its domain of application. ‘As wanted’ assimilates both how well things are done by the system and the efforts required by the doing. (F4) These are the primary constituents of the concept of performance. ‘As wanted’ performance of an interactive system is conceptualised such that as wanted might be either absolute or relative, as in a comparative performance to be matched or improved upon. (C18) (F5)

Key concepts appear in bold on their first reference only.

Footnotes and Citations

Footnotes

 (F1) ‘As wanted’, here, may refer to individuals or groups, or indeed both, as in: users; clients etc.

(F2) ‘Implement and test’ design practices include, more generally, ‘trial and error’; ‘prototype and iterate (and test)’ practices etc.

(F3) ‘Effort’ is intended in no way to be restrictive. Different approaches have different concepts for what is required, for example, engagement; fun; experience, motivation etc.

(F4) See F3 above). (F5) Performance is not intended here to be restrictive. Different approaches to HCI have many different concepts, for example, efficiency; effectiveness; engagement; fun; experience etc.

Citations

 Dowell and Long (1989)

(C1) ‘…….. a conception of the general design problem …….. is expressed informally as: ‘to design human interactions with computers for effective working’.’  (Page 1513, Lines 12-13)

(C2) ‘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. Hence, the requirement for a conception for the HF discipline is concluded (Section 1.5.).’ (Page 1514, Lines 19-22)

(C3) ‘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 39-41)

(C4) ‘…….. one class of general problem is that of the general design problem and includes the design of artefacts (of bridges, for example) and the design of ‘states of the world’ (of public administration, for example).’ (Page 1524, Lines 43-45)

(C5)’…….. any general problem has the necessary property of a scope, delimiting the province of concern of the associated discipline.’ (Page 1514, Lines 47 and 48)

(C6) The scope of the HCI general design problem includes: humans, both as individuals, as groups, and as social organisations; computers, both as programmable machines, stand-alone and networked, and as functionally embedded devices within machines; and work, both with regard to individuals and the organisations in which it occurs. (Page 1515, Lines 11-14)

(C7) ‘A discipline’s practices construct solutions to its general design problem……..  disciplines appear to differ in the completeness with which they specify solutions to their respective general design problems before implementation occurs. ……..’ (Page 1517, Line 46; Page 1518, Lines 2 and 3).

(C8) ‘The interactive worksystem can be distinguished as two separate, but interacting sub-systems, that is, a system of human behaviours interacting with a system of computer behaviours.’ (Page 1523, Lines 1-3)

(C9) ‘The general design problem of HF then, is one of producing implementable specifications of human behaviours {U} which , interacting with computer behaviours {C}, are constituted within a worksystem {S} whose performance conforms with a desired performance (Pd).’ (Page 1523, Lines 11-14)

(C10) ‘The conception for HF identifies a world in which work originates, is performed and has its consequences. This section presents the concepts by which work and its relations with the user are expressed.’ (Page 1523, Lines 19 and 20)

(C11) ‘Organisations are conceptualised as having domains as their operational province ……..  It is a requirement satisfied through work.’ (Page 1524, Lines 36-38)

(C12) ‘The conception for HF identifies interactive worksystems consisting of human and computer behaviours together performing work.’ (Page 1526, Lines 2 and 3)

(C13) ‘Humans are able to conceptualise goals and their corresponding behaviours are said to be intentional (or purposeful). Computers, and machines more generally, are designed to achieve goals, and their corresponding behaviours are said to be intended (or purposive1). An interactive worksystem   (‘worksystem’) is a behavioural system distinguished by a boundary enclosing all human and computer behaviours whose purpose is to achieve and satisfy a common goal.’ (Page 1526, Lines 5-11)

(C14) ‘The behaviours of the human and computer are conceptualised as behavioural sub-systems of the worksystem – sub-systems which interact.’ (Page 1526, Lines 24 and 25)

(C15) ‘The behaviours constituting a worksystem are both physical as well as abstract.’ (Page 1526, Lines 39 and 40)

(C16) ‘Although the human and computer behaviours may be treated as separable sub-systems of the worksystem, those sub-systems extend a “mutual influence”, or interaction whose configuration principally determines the worksystem (Ashby, 1956).’ (Page 1527, Lines 24-27)

(C17) ‘The user may include both on-line and off-line human behaviours………’ (Page 1528, Lines 8 and 9) .

(C18) ‘A desired performance of an interactive worksystem may be conceptualised. Such a desired performance might either be absolute, or relative as in a comparative performance to be matched or improved upon.’ (Pages 1531. Lines 8-10)

(C19)……..’ Instances of the general design problem may include the development of a worksystem, or the utilisation of a worksystem within an organisation. Developing worksystems which are effective, and maintaining the effectiveness of worksystems within a changing organisational environment, are both expressed within the problem.’(Page 1532, Lines 16-20)