Editing Design (section)

==Design process==
Substantial disagreement exists concerning how designers in many fields, whether amateur or professional, alone or in teams, produce designs.<ref>{{Cite journal |last=Coyne |first=Richard |date=1990 |title=Logic of design actions |url=http://dx.doi.org/10.1016/0950-7051(90)90103-o |journal=Knowledge-Based Systems |volume=3 |issue=4 |pages=242–257 |doi=10.1016/0950-7051(90)90103-o |issn=0950-7051 |access-date=2020-10-01 |archive-date=2022-08-27 |archive-url=https://web.archive.org/web/20220827204830/https://www.sciencedirect.com/science/article/abs/pii/095070519090103O?via%3Dihub |url-status=live|url-access=subscription }}</ref> Design researchers Dorst and Dijkhuis acknowledged that "there are many ways of describing design processes," and compare and contrast two dominant but different views of the design process: as a rational problem-solving process and as a process of reflection-in-action. They suggested that these two [[paradigm]]s "represent two fundamentally different ways of looking at the world{{snd}} [[positivism]] and [[Constructionism (learning theory)|constructionism]]."<ref>{{cite journal |doi=10.1016/0142-694X(94)00012-3 |title=Comparing paradigms for describing design activity |journal=Design Studies |volume=16 |issue=2 |pages=261–274 |year=1995 |last1=Dorst |first1=Kees |last2=Dijkhuis |first2=Judith |url=https://dx.doi.org/10.1016/0142-694X%2894%2900012-3|url-access=subscription }}</ref> The paradigms may reflect differing views of how designing ''should be'' done and how it ''actually is'' done, and both have a variety of names. The problem-solving view has been called "the rational model,"<ref name="Brooks"/> "technical rationality"<ref name="Schön 1983"/> and "the reason-centric perspective."<ref name="Ralph 2010"/> The alternative view has been called "reflection-in-action,"<ref name="Schön 1983"/> "coevolution"<ref name=DC/> and "the action-centric perspective."<ref name="Ralph 2010"/>

===Rational model===
The rational model was independently developed by Herbert A. Simon,<ref>Newell, A., and Simon, H. (1972) ''Human problem solving'', Prentice-Hall, Inc.</ref><ref name="Simon">Simon, H.A. (1996) [https://books.google.com/books?id=k5Sr0nFw7psC The sciences of the artificial] {{Webarchive|url=https://web.archive.org/web/20131217052045/http://books.google.com/books?id=k5Sr0nFw7psC&printsec=frontcover |date=2013-12-17 }}, MIT Press, Cambridge, MA, USA. p. 111. {{ISBN|0-262-69191-4}}.</ref> an American scientist, and two German engineering design theorists, Gerhard Pahl and Wolfgang Beitz.<ref>Pahl, G., and Beitz, W. (1996) [https://books.google.com/books?id=8fuhesYeJmkC ''Engineering design: A systematic approach''] {{Webarchive|url=https://web.archive.org/web/20131217052518/http://books.google.com/books?id=8fuhesYeJmkC&printsec=frontcover |date=2013-12-17 }}, Springer-Verlag, London. {{ISBN|3-540-19917-9}}.</ref> It posits that:
# Designers attempt to [[Optimization (mathematics)|optimize]] a design candidate for known [[constraint optimization|constraints]] and [[Goal|objectives]].
# The design process is plan-driven.
# The design process is understood in terms of a discrete sequence of stages.

The rational model is based on a [[Rationalism|rationalist philosophy]]<ref name="Brooks" /> and underlies the [[waterfall model]],<ref name=Royce/> [[systems development life cycle]],<ref name=Bourque/> and much of the [[engineering design]] literature.<ref>Pahl, G., Beitz, W., Feldhusen, J., and Grote, K.-H. (2007 ) [https://books.google.com/books?id=qsKNwB2gL5wC Engineering design: A systematic approach] {{Webarchive|url=https://web.archive.org/web/20131217050322/http://books.google.com/books?id=qsKNwB2gL5wC&printsec=frontcover |date=2013-12-17 }}, (3rd ed.), Springer-Verlag, {{ISBN|1-84628-318-3}}.</ref> According to the rationalist philosophy, design is informed by research and knowledge in a predictable and controlled manner.<ref>{{Cite book |last=Mielnik |first=Anna |url=https://suw.biblos.pk.edu.pl/downloadResource%26mId%3D2650996 |title=Under the power of reason |publisher=Krakow University of Technology |access-date=2022-08-27 |archive-date=2022-08-27 |archive-url=https://web.archive.org/web/20220827204829/https://suw.biblos.pk.edu.pl/downloadResource%26mId%3D2650996 |url-status=live}}</ref>

Typical stages consistent with the rational model include the following:<ref>{{Cite journal |last1=Condrea |first1=Ionut |url=https://media.proquest.com/media/hms/PFT/1/MNTnI?_s=zo3qVt0Rq8V3x%2FgZKecWt8ICAzY%3D |title=Elaboration of the initial requirements in the design activities |last2=Botezatu |first2=C. |last3=Slătineanu |first3=L. |last4=Oroian |first4=B. |journal=IOP Conference Series: Materials Science and Engineering |date=February 2021 |volume=1037 |issue=1 |page=012002 |doi=10.1088/1757-899X/1037/1/012002 |bibcode=2021MS&E.1037a2002S |s2cid=234019940|doi-access=free }}</ref>
* Pre-production design
** [[Design brief]]&nbsp;– initial statement of intended outcome.
** [[Analysis]]&nbsp;– analysis of design goals.
** [[Research]]&nbsp;– investigating similar designs in the field or related topics.
** [[Specification]]&nbsp;– specifying requirements of a design for a product ([[product design specification]])<ref>Cross, N., (2006). ''T211 Design and Designing: Block 2'', p. 99. Milton Keynes: The Open University.</ref> or service.
** [[Problem solving]]&nbsp;– [[wikt:conceptualize|conceptualizing]] and [[document]]ing designs.
** [[Presentation]]&nbsp;– presenting designs.
* Design during production.
** [[Product development|Development]]&nbsp;– continuation and improvement of a design.
** [[Product testing]]&nbsp;– ''[[in situ]]'' testing of a design.
* Post-production design feedback for future designs.
** [[Implementation]]&nbsp;– introducing the design into the environment.
** [[Evaluation]] and [[logical consequence|conclusion]]&nbsp;– summary of process and results, including [[constructive criticism]] and suggestions for future improvements.
* Redesign&nbsp;– any or all stages in the design process repeated (with corrections made) at any time before, during, or after production.

Each stage has many associated [[best practices]].<ref>Ullman, David G. (2009) ''The Mechanical Design Process'', Mc Graw Hill, 4th edition {{ISBN|0-07-297574-1}}</ref>

====Criticism of the rational model====
The rational model has been widely criticized on two primary grounds:

# Designers do not work this way&nbsp;– extensive empirical evidence has demonstrated that designers do not act as the rational model suggests.<ref name="Schön 1983"/><ref name="Ralph 2010"/><ref name=Cross/>
# Unrealistic assumptions&nbsp;– goals are often unknown when a design project begins, and the requirements and constraints continue to change.<ref name="Brooks"/><ref>{{cite journal |doi=10.1145/1005937.1005943 |url=http://www.deepdyve.com/lp/association-for-computing-machinery/life-cycle-concept-considered-harmful-WXRCv45NVM |author1=McCracken, D.D. |author2=Jackson, M.A. |title=Life cycle concept considered harmful |journal=ACM SIGSOFT Software Engineering Notes |volume=7 |issue=2 |year=1982 |pages=29–32 |s2cid=9323694 |access-date=2012-03-25 |archive-date=2012-08-12 |archive-url=https://web.archive.org/web/20120812035944/http://www.deepdyve.com/lp/association-for-computing-machinery/life-cycle-concept-considered-harmful-WXRCv45NVM |url-status=live|doi-access=free }}</ref>

===Action-centric model===
The action-centric perspective is a label given to a collection of interrelated concepts, which are antithetical to the rational model.<ref name="Ralph 2010"/> It posits that:

# Designers use [[creativity]] and [[emotion]] to generate design candidates.
# The design process is [[Improvisation|improvised]].
# No universal sequence of stages is apparent&nbsp;– analysis, design, and implementation are contemporary and inextricably linked.<ref name="Ralph 2010"/>

The action-centric perspective is based on an [[Empiricism|empiricist philosophy]] and broadly consistent with the [[Agile software development|agile approach]]<ref name=Beck/> and methodical development.<ref name=Truex/> Substantial empirical evidence supports the veracity of this perspective in describing the actions of real designers.<ref name=Cross/> Like the rational model, the action-centric model sees design as informed by research and knowledge.<ref>{{Cite web |last1=Faste |first1=Trygve |last2=Faste |first2=Haakon |date=2012-08-15 |title=Demystifying "design research": design is not research, research is design |url=https://www.idsa.org/sites/default/files/Faste.pdf |access-date=2022-08-19 |website=Industrial Designers Society of America |archive-date=2022-08-19 |archive-url=https://web.archive.org/web/20220819163610/https://www.idsa.org/sites/default/files/Faste.pdf |url-status=live}}</ref>

At least two views of design activity are consistent with the action-centric perspective. Both involve these three basic activities:
* In the [[Reflective practice|reflection-in-action paradigm]], designers alternate between "[[Framing (social sciences)|framing]]", "making moves", and "evaluating moves". "Framing" refers to conceptualizing the problem, i.e., defining goals and objectives. A "move" is a tentative design decision. The evaluation process may lead to further moves in the design.<ref name="Schön 1983" />
* In the sensemaking–coevolution–implementation framework, designers alternate between its three titular activities. [[Sensemaking (information science)|Sensemaking]] includes both framing and evaluating moves. Implementation is the process of constructing the design object. Coevolution is "the process where the design agent simultaneously refines its mental picture of the design object based on its mental picture of the context, and vice versa".<ref name="Ralph 2010" />

The concept of the [[design cycle]] is understood as a circular time structure,<ref>Fischer, Thomas "Design Enigma. A typographical metaphor for enigmatic processes, including designing", in: T. Fischer, K. De Biswas, J.J. Ham, R. Naka, W.X. Huang, ''Beyond Codes and Pixels: Proceedings of the 17th International Conference on Computer-Aided Architectural Design Research in Asia'', p. 686</ref> which may start with the thinking of an idea, then expressing it by the use of visual or verbal means of communication (design tools), the sharing and perceiving of the expressed idea, and finally starting a new cycle with the critical rethinking of the perceived idea. Anderson points out that this concept emphasizes the importance of the means of expression, which at the same time are means of perception of any design ideas.<ref>Anderson, Jane (2011) ''Architectural Design'', Basics Architecture 03, Lausanne, AVA academia, p. 40. {{ISBN|978-2-940411-26-9}}.</ref>