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Sequence of activities for the experiment A Logitech digital pen and paper note book was used to convert and store a digital copy of the design sketches and written notes that the desig

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and coding could not begin until the design activity

had finished

Table 2 Sequence of activities for the experiment

A Logitech digital pen and paper note book was used

to convert and store a digital copy of the design

sketches and written notes that the designer created

though the process The digital notebook also

contained a column that was used by the researcher to

code the design outputs Almost all of the design

outputs were also modeled using computer-aided

design (CAD), and it is these representations, which

were then presented in sequence with significant

descriptive notes, that were formally coded

The design task itself is not described in this paper,

as it is a real task previously performed in industry and the researchers are planning to compare the outputs from the experiment with those from industry

Table 2 above describes the sequence of activities that took place in the experiment and highlight the particular roles that the various researchers (referred to

as HY, TJH and EAD) played

Figure 1 below shows an example of how the design ideas were presented in sequence and how they were formally coded The first two columns show the numbering system used for the design ideas B1 represents an initial, unique design idea B2, B3 and B4 show the iterations of this design idea The last five columns show how each of the design ideas were coded using both the 1st and 2nd coding schemes developed in this research

3 Results

Looking at the whole data set in the first round showed that, for 18 out of the 30 design ideas coded the researchers agreed, whilst in 12 cases the coders were not in agreement It was this disagreement and the following discussion that lead the development of the 2nd coding scheme

Table 3 below shows a sample of the discussion from the 12 cases where the coders were not in agreement

Table 3 Sample of the coding disagreement discussion

Some observations and recommendations were drawn from the disagreements above:

 A reference design that the new design idea is compared to should be specified before coding This seems obvious in retrospect, as it is impossible to code the initial set of ideas without a reference design: a change needs to

be coded relative to something Once the initial

Resear-cher ID

role played (designer-researcher)

st round

Development of the

1st coding scheme:

Creative Modes of

Change

TJH researcher

Briefing on the

highly-constrained

Development of

Review and iteration

of the design ideas

HY TJH designer Coding the design

ideas using 1st coding

scheme

HY researcher Assessing the quality

of design ideas using

company’s Criteria

Decision (MCDA)

table

HY TJH designer

Inter-observer coding

of the design ideas

using 1st coding

scheme

TJH EAD researcher

nd Ro

Development of

design ideas – With

creativity tools

HY designer Coding the design

ideas using 2nd

coding scheme

HY researcher Assessing the Quality

of design ideas using

the company’s

MCDA table

HY TJH designers Analysis of results all researcher

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ideas are coded, subsequent design iterations

can be coded relative to each one preceding it

 Although all coders were given definitions for

each code, coders should be trained in advance

using an example to elicit queries and tease out

any problems with the coding scheme

 One of the requirements of New Auxiliaries

(NA) is to bring in new functions that are not

listed in the original functional requirement

This caused some disagreements when new

elements were added to the system, and

highlighted the need for clear definitions of

‘system’, ‘element’ and ‘function’ (see section

3.1.2) The coding scheme could be improved

by defining New Auxiliaries as an additional

element/module instead of additional function

For differentiating whether a new function is

added, the outcome of the modification can

also be coded as Additional Function or

Reduced Function;

 Quite often Technology Pull (TP) or Improved

Understanding (IU) cannot be indentified

without knowing the rationale from the

designer who made the modification For

example in design idea E2, researcher HY coded the concept as New Design (ND) since being the designer, he knew that the reason for the modification was the need to integrate a hinge to a flap However, the other researchers (TJH and EAD) considered the change as the result of new material (thin and flexible plastic) therefore coded that change as Technology Pull (TP) In idea F2 a very similar situation arose, but the other way round It is therefore clearer to separate Improved Understanding (IU) and Technology Pull (TP) from rest of the modes of change and code them as the factors that drive the design modification (or design rationale)

 Researcher TJH suggested Modularization as a new mode of change when coding design idea A2, in order to provide a mode of change that

is opposite to Functional Integration (FI)

 A similar approach was applied to New Auxiliaries (NA) where; Trimming could be introduced as a new MOC that describes the modification that discards unnecessary element to improve performance

Fig 1 Sample of design idea formal coding sheet

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3.1 Introducing the 2nd coding scheme

The modified scheme comprises three ‘levels’ of

design change to be coded: the factor that drives the

modification, the design modification itself, and the

final resulting effect on the system from the

modification Figure 2 shows the three levels used in

this 2nd coding scheme

Fig 2 Three levels of the 2nd coding scheme

3.1.1 Factor that drives the design change

The coding in this section describes the various types

of rationale which can drive the specific design

modifications Design rationale includes ‘not only the

reasons behind a design decision but also the

justification for it, the alternatives considered, the

trade-offs evaluated and the argumentation that led to

the decision’ (Lee, 1997) These are not obvious by

simply looking at the design modifications themselves

Even for the same design modification, the underlying

rationale may be different and therefore usually best

described by the designer who made the modification

 New requirement (NR) - One or more new

requirements raised by

market/organization/designer, or any other

party, that requires new design ideas to

achieve

 Improved understanding of design

performance parameter (IU) - Through

modelling and empiricism engineers benefit

from the discovery - or better understanding -

of relationships between the design parameters and the performance This understanding can then go on to drive various design modifications

 Technology Pull (TP) - The adoption of a novel and appropriate technology or material

to expand the design space, which can then in turn drive various design modifications This may simply have a direct relationship to performance, such as changing material to reduce weight However, it could lead to more complex relationships One example observed

in recent research, was where a new material coating was adopted, which enabled a different spray coating process, and eradicated post process machining, thereby producing substantial benefits

 Design Improvement (DI) - Without adding any new requirement, the rationale of the modification is only to further improve the performance of the system During the iterations of design ideas, the designer sometimes sees opportunities to set higher targets for the system This raises the standard for the design ideas without adding any new requirements

3.1.2 Design Modification

These define the ways in which each design idea presented differs with respect to the reference design

In this study, the initial unique design idea presented (e.g B1) was compared to a common solution already

on the market The subsequent design iterations (e.g B2, B3, etc.) were coded relative to each one preceding it The codes presented below are based on the assumption that in highly-constrained design tasks, the designer is usually designing ‘elements’ (parts) of

a sub-system, which perform particular ‘functions’ for the ‘system’ (or super-system) The different types of changes that are seen as the design ideas evolve are defined as:

 Parameter Change (PC) - In this change the parameter of an existing design element is modified However the ‘performance - attribute’ relationships governing the design are not changed as a parameter is adjusted Thus changing the ‘number of wheels on a car’

is not a parameter change, as new

‘performance – attribute’ relationships are inevitably formed when changing the number

of wheels

 New Auxiliaries (NA) - In this change a new function which was not a part of the system,

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and is distinct from any other function within

the system, is added into the system

 Modularisation (MD) - In this change the

functional requirements of a system are

fulfilled by an increased number of

sub-systems, parts or features This may for

example, be beneficial to the design in terms

of: increasing reliability, adaptability, or

performance Suh (1990) for example,

advocates decoupling functions such that each

function has a single associated part or feature

 Functional integration (FI) - In this change any

two or more elements within the system are

combined into a single element that performs

the same function

 New Design (ND) - In this change an existing

function is performed by a completely new

element

 Trimming (TM) - This change occurs when

any element is discarded

3.1.3 Modification outcome

Codes in this section describe the different types of

outcome observed for the overall system These

describe changes in the overall function or

performance or the final resultant benefits to the

system from the creative design modifications

 Better performance (BP) - The existing system

performs better

 Additional function (AF) - Extra function is

added to the system The function may or may

not have been part of the original functional

requirements A creative design modification

occurring during the process may add

additional beneficial functions to the system

Reduced function (RF) - Function is discarded

from current design, a direct opposition to Additional

Function, in order to improve the overall performance

of the system

3.2 Reviewing the coded concepts on a timeline

Figure 3 on next page presents all the design ideas on

the project day-by-day timeline For example, A3 (PC)

means the third iteration of the initial idea A1, where

Parameter Change is the Mode of Change evident in

the design Only the agreed coding from round 1 is

included in brackets behind the concept numbers In

order to use the 1st and 2nd round of design and

analysis as a single data set, only the Design

Modification codes of the 2nd Coding scheme are

presented in this diagram as they are coded at the same

‘level’

There were 6 days between the two rounds were no new concepts were generated It is possible to detect some patterns of modes of change that occur throughout a creative design process, these are discussed in section 4.2 Each of the final concepts (e.g A9, B5, C3, etc) was given a Quality score from the company’s Multi Criteria Decision Analysis (MCDA) table The company’s MCDA table consists

of eight criteria against which each concept is scored, these are added up to generate the Quality score The MCDA includes functional criteria such as ‘hold low vacuum’ and ‘hygienic’ as well as business criteria such as ‘product cost’ and ‘development time required’ The Quality score is shown below in bold and is out of maximum of 72 Whether particular patterns lead to more successful outcomes in terms of solution quality is discussed in section 4.2

4 Discussion

This section discusses the design modification codes (middle ‘level’) from the 2nd coding scheme as these were analysed in more depth than the results from the other two levels It also makes general observations about the modes of change observed

4.1 Discussion of the 2nd coding scheme

In practice in the study, the codes were created through the action research cycle, using a type of content analysis, where definitions of codes were adjusted, and new codes were created, in order to be able to code the entire data set In retrospect, it is possible to view the codes created in this research as describing two fundamental aspects that change: the functions that are performed by the design and the actual designed elements that perform those functions They change by creating, discarding or integrating Figure 4 below shows how the definitions of the codes presented in section 3.1.2 can be placed in the matrix

Fig 4 Matrix of Design modification codes relating to

changes in elements and functions

existing new integrate discard

n existing PC

ND

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This helps to highlight the difference between New

Design (existing function is performed by a new

element) and New Auxiliaries (new function is added

into the system) The matrix also highlights an

anomaly in one of the codes Functional integration

(FI) is actually defined as the integration of elements,

and should perhaps be relabeled as Element

Integration (EI) The table also points towards the

opportunity to define other Design Modifications that

did not arise in this experiment but could be useful

both for coding future experiments, for example: the

integration of existing functions through the design of

a new element (a); or creation of a new function by

integrating existing elements (b)

Although the single case presented here does not

allow detailed analysis of the three ‘levels’ coded in

the 2nd coding scheme they do provide some insights

into the nature of creativity in highly-constrained

design tasks At the top level, it may be possible to

develop/specify tools that stimulate designers to think

of strategies that then drive successful design

modifications These types of tools would have to

work through stimulating/guiding design rationale

Looking at the middle level where the design ideas

themselves are coded, it may be possible to specify

particular creativity tools to stimulate particular design

modifications This experiment was able to initiate this

work which is reported in (in preparation for ICED11)

It is worth noting that before this can be done, a much

larger study is needed to understand the design modifications - or patterns of them - that deliver the most creative results in highly-constrained design tasks At the third (outcome) level it may be possible

to develop/specify tools that stimulate designers to think of strategies for the system that then drive successful design modifications at the sub-systems level

4.2 Patterns in Modes of Change

Studying the data in Figure 3, it is possible to detect some patterns of modes of change that occur throughout a creative design process These findings are tentative observations due to the limited number of coded instances In most cases it is clear that the initial idea (e.g B1, C1, D1, etc) starts with a New Design (ND) (round 1) or a New Auxiliary (NA) (round 2) followed by iterations of the ideas in the form of Parameter Change (PC) In some cases this works the other way round where successive iterations of Parameter Change (PC) lead to New Designs (ND) in the final instance (e.g A8 and F6) This may happen where the designer feels they have pushed the idea to its limits and thus comes up with a totally new direction to explore The difference between the number of New Design (ND) and a New Auxiliary (NA) codes between the two rounds is likely to be mainly due to changes in the coding scheme

A1, B1(ND)

A2,C1 (ND)

D1 (ND), E1 (ND)

C3 (PC)

32 , D2

(PC) 38 , E2, E3 34

A3 (PC), A4 (PC)

B2 (PC), B3 (PC)

A6, A7(PC), A8(ND),

A9 42 ,

B4(PC), F4, F5(PC), F6(ND),

F7 24

B5 40

G1 (ND)

46 , H1

(NA)

I1 (NA)

27 ,

J1(NA)

K1(NA), K2 (ND)

38

L1 (NA), M1 (NA)

35 ,

N1(NA)

H2 (PC)

44 , L2

(NA), L3

(PC) 21 ,

O1 (NA)

31

J2

(PC)26 ,

N2 (PC)

35

2nd Round of design

1st round of design

1st round of design

Fig 3 Overview of all design ideas, coded on the project timeline day-by-day

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Each of the final concepts (e.g A9, B5, C3, etc) was

given a Quality score from the company’s MCDA

table The score is shown in Figure 3 in bold and is out

of maximum of 72 From this data there is no clear

quality difference between the design output from

round 1 without creativity tools (average score: 35)

and round 2 with creativity tools (average score: 34)

However the pattern in which solutions were generated

was significantly different, where in round 1 most

initial ideas (6 in total) were iterated several times

(usually through Parameter Change), round 2 yielded

many more initial ideas (9 in total) There was

however no pattern in the quality scores linked to the

time spent (number of days) or any benefit of ‘carrying

the ideas’ through (number of iterations)

Coding design output in this way may contribute

one way of mapping the way designers move around

the design space, and particularly the strategies that are

used by creative designers to skip from one ‘train of

solutions’ to new avenues

5 Conclusions

This paper shows that it is possible to categorise

design changes into different creative modes of change

using the coding scheme developed The coding

scheme can be made more robust by: ensuring design

change is always coded relative to a reference design;

tightening up definitions of ‘system’, ‘element’ and

‘function’; and using a matrix, such as the one

presented in Figure 4, to develop a more complete set

of codes

A much larger study with more designers working

on different types of highly-constrained design task is

needed, in order to draw conclusions on the modes of

change and their relationship to creativity Design

research would benefit even more if such a study was

conducted in industry The single case presented here

does show that there can be creative steps in each type

of mode of change One promising area identified for

further research is to look at the patterns of modes of

change that occur throughout a creative design

process Some common patterns were identified in this

paper, but there were no links between patterns and

final outcomes in terms of solution quality The methodology could be made more robust if the designers and researcher coded separately and data was triangulated with direct observations, ‘thinking aloud’ protocol or reflective interviews

Although in this case we did not measure creativity

as part of the study, the coding tool developed will help to map the way designers move around the design space, and particularly the strategies that are used by creative designers to skip from one ‘train of solutions’

to new avenues

The coding scheme can ultimately perform two functions for design research: firstly by understanding existing practice in greater detail (e.g conducting a study of particularly talented/creative designers working on highly-constrained design tasks); or using even early outcomes iteratively to specify/develop tools to stimulate creativity in highly-constrained design tasks (e.g cycles of action research that develop and test tools stimulating/guiding particularly creative design rationale)

References

Bjork E, Ottosson S, (2007) Aspects of consideration in product development research Journal of Engineering Design 18(3):195–207

Brown DC, (2010) The Curse of Creativity In proceedings

of DCC10: The 4th International Conference on Design Computing and Cognition, Stuttgart, Germany, 12–14 July

Hales C, (1986) Analysis of the engineering design process

in an industrial context Mechanical Engineering: Cambridge, University of Cambridge

Lee J, (1997) Design rationale systems: understanding the issues IEEE Expert 12(3):78–85

McMahon CA, (1994) Observations on modes of incremental change in design Journal of Engineering Design 5(3):195–209

Pahl G, Beitz W, (1984) Engineering Design Design Council/ Springer: London

Suh N, (1990) The Principles of Design Oxford University Press: USA

Vincenti W, (1990) What Engineers Know and How they Know It John Hopkins University Press: Baltimore, MD

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Effectiveness of Brainwriting Techniques: Comparing Nominal Groups to

Real Teams

Julie S Linsey and Blake Becker

Texas A&M University, USA

Abstract Engineering designers need effective and efficient

methods for idea generation This study compares the

effectiveness of group idea generation techniques to the

combined efforts of individuals working alone with

redundant ideas removed, so called “nominal groups”

Nominal groups compared to real interacting groups is a

standard approach for determine if a group idea generation

method can produce better solutions then individuals

working alone This study compares nominal group data to

existing data on a series of group idea generation techniques

Results show that groups using rotational viewing and

representing their ideas with words & sketches, a hybrid

6-3-5 method, outperform nominal groups in number ideas and

have an equal level of quality This result is in contrast to

comparing Brainstorming groups to nominal groups where

nominal groups outperform Brainstorming groups These

results indicate that a team can be more effective than

individuals working separately

Keywords: creativity, idea generation, brainwriting

1 Introduction and Background

Over one hundred formal idea generation techniques

have been developed in areas such as psychology,

business, and engineering (Adams, 1986; VanGundy,

1988; Higgins, 1994) Some methods like Osborn’s

Brainstorming have received significant evaluation

whereas for many graphical methods there is little data

available

One of the first studies using Osborn’s

Brainstorming method in engineering design included

engineering professionals working on a realistic

engineering problem and showed that groups using

brainstorming produced fewer ideas than the combined

efforts of an equivalent number of individuals working

alone (Lewis, et al., 1975) This result, called

productivity loss, is consistent with the vast majority

of studies on variations of Osborn’s Brainstorming

(Mullen, et al., 1991)

While the data on Brainstorming techniques is

extensive, there is far less data available on

brainwriting techniques where communication is

through written words or sketches For brainwriting techniques, some data suggests that groups can be more effective than the combined individual efforts (Gryskiewicz, 1988; Paulus and Yang, 2000) Recent studies have focused on the development and evaluation of more effective idea generation methods

in engineering and design related fields, including industrial design and architecture (Shah, 1998; Shah,

et al., 2000; Van der Lugt, 2002; Shah, et al., 2003; Vidal, et al., 2004) These studies have used a mixture

of sketches, verbal descriptions of ideas, and physical models in the idea generation process Prior work on graphical brainwriting techniques (e.g., Brainsketching, C-Sketch, Gallery), has not compared nominal groups (non-interacting individuals whose non-redundant results are combined) with real interacting groups

Our study compares nominal groups with group ideas generation methods: Brainsketching, C-Sketch, 6-3-5, and the first phase of the Gallery method These methods are gaining popularity and exposure in the engineering research community, in addition to industrial application They also form a diverse set of group idea generation techniques that vary in how ideas are exchanged and in the types of representations used (written words, sketches, etc.) To understand the theoretical basis of these method, we dissect them into two key factors (1) how a group’s ideas are displayed

to other members (“rotational view” or all are posted

in “gallery view”) and (2) the form of communication between group members (no communication, written words only, sketches only or a combination of words and sketches.) All other method parameters are kept constant for all experimental conditions

1.1 Osborn’s Brainstorming

The term “brainstorming” is frequently applied to idea generation techniques in general and not just to the technique developed and named by Osborn Osborn’s Brainstorming begins with a facilitator explaining the problem A group then verbally exchanges ideas

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following four basic rules: (1) criticism is not allowed,

(2) “wild ideas” are welcomed, (3) building off each

others’ ideas is encouraged, and (4) a large quantity of

ideas is sought Despite the face validity of these rules,

much research demonstrates productivity loss in

brainstorming compared to an equal number of

individuals working alone (nominal groups) (Mullen,

et al., 1991)

Silent Sketching

More Silent Sketching Review and Discussion

Fig 1 Illustration of Gallery method

1.2 Brainsketching

In Brainsketching, individuals begin by silently

sketching their ideas on large sheets of paper including

brief annotations Group members exchange drawings

and silent sketching continues for another period of

time (VanGundy, 1988) This technique allows for a

visual means of expression, and so it is well suited for

product design Van der Lugt used teams of advanced

product design students to compare Brainstorming to a

variant of Brainsketching (that included the

explanation of ideas between exchanges) (Van der

Lugt, 2002) The Brainsketching variant led to more

cases in which group members built on previously

generated ideas than did Brainstorming

1.3 Gallery

In the Gallery method, individuals begin by sketching

their ideas silently on large sheets of paper After a set

amount of time, participants discuss their ideas and

move about the room studying others’ ideas This

review phase is followed by a second stage of silent

sketching (VanGundy, 1988; Pahl and Beitz, 1996; Shah, et al., 2001) The review phase allows team members to clarify their ideas, and it provides social interaction

Fig 2 Illustration of 6-3-5 and C-Sketch Six people

silently describe three ideas on a sheet of paper and then exchange papers

1.4 C-Sketch / 6-3-5

For 6-3-5 (Shah, 1998; Otto and Wood, 2001; Shah, et al., 2001) and C-Sketch (Shah, 1998), six (“6”) participants are seated around a table, and each silently describes three (”3”) ideas on a large sheet of paper The ideas are then passed to another participant This exchange goes on for five (“5”) rounds For the original 6-3-5 method, ideas are described using only words In contrast, the C-Sketch, method permits only sketches One advantage of C-Sketch over 6-3-5 is that sketches are typically ambiguous, and so one person may misinterpret aspects of someone else’s sketch, which may lead to new ideas (Shah, et al., 2001) Other variations of 6-3-5 have also been proposed (VanGundy, 1988; Otto and Wood, 2001) One variation permits annotated sketches (Otto and Wood, 2001) In experimental comparisons with different conditions than those reported in this paper, C-Sketch and Gallery outperformed 6-3-5 (words only) for variety, quality and novelty of ideas (Shah, et al., 2001) Novelty is how unique a particular idea is and variety is how much of the design space is captured by

a set of ideas This previous study used groups of mechanical engineering undergraduates, mechanical engineering graduate students and professional designers Each group was evaluated on all three techniques and a different design problem was solved for each of the techniques This design eliminated individual differences as a noise variable but caused the technique results to be confounded with the design problem

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2 Experimental Approach and Research

Questions

Engineers seek a robust idea generation method for

predictably producing a large quantity of high quality,

novel product solutions Using a factorial design of

experiments, our study explores the influence of the

representation used to communicate ideas and how

ideas are displayed to individuals We seek to answer

the following research questions:

 Research Question: How do the nominal

groups compare to real groups in terms of

quantity and quality of ideas?

This research questions is addressed systematically in

the following sections We discuss our experimental

method, metrics for evaluation, data analysis approach

and the results

3 Experimental Method

We conducted a factorial experiment in order to

explore the effects of two key factors on the outcome

of group idea generation The first factor controls how

participants view the ideas, either all ideas are posted

via gallery (on the wall), sets of ideas are rotated

between participants, or they are not exchanged

(individual idea generation-nominal groups) The

second factor controls how participants represent their

ideas Participants either use written words only,

sketches only, or a combination of written words and

sketches to communicate ideas to their teammates A 2

(Display of ideas: “gallery” or “rotational view”) X 3

(Representation: words only, sketches only, or words

combined with sketches) factorial experimental design

is used (Table 2) No oral discussions are allowed

during the session; all communication is written This

approach produces methods similar to 6-3-5 (Pahl and

Beitz, 1996), C-Sketch (Shah, 1998), Brainsketching

(VanGundy, 1988), or Gallery Method (Pahl and

Beitz, 1996), as shown in Table 3 All participants solved the peanut sheller problem (Linsey, et al., accepted)

3.1 Factor 1: Display of Ideas

One key factor in this study is whether ideas are displayed all at once or whether participants see only a subset at any given moment In the “gallery view” condition, all ideas generated by the team are posted

on the wall, so all participants can see all of the ideas

at the same time This approach results in a method similar to Gallery Method or Brainsketching (VanGundy, 1988; Pahl and Beitz, 1996) In the

“rotational view” condition, ideas are passed around the table, so that each participant sees only a subset of the ideas at any given moment This condition is similar to 6-3-5 or C-Sketch (Pahl and Beitz, 1996; Shah, 1998; Otto and Wood, 2001)

3.1.1 Gallery View Condition- Similar to Brainsketching or Gallery Method

For the first 10 minute period, each student is given a number of paper sheets and told to write down at least two ideas on separate sheets of paper Sheets are collected as participants finish, but are not displayed until the end of the period The time period length is based on the available time and recommendations from the literature, which vary from five to 15 minutes (VanGundy, 1988; Baxter, 1995; Shah, et al., 2000) The ideal time period for the methods under evaluation

is not explicitly known and is not one of the experimental parameters At the end of the first period, all sheets are numbered and posted gallery style on the wall In the four subsequent 7.5 minute periods, ideas are posted as they occur and participants are told to execute one of the following options:

2 Add new ideas to one of the posted drawings Participants can request a drawing by writing down its number on a small sheet of paper

7 Make a separate drawing that is related to the

Table 1 Experimental conditions

Factor 2: Representation

Words Only Sketches Only Words and Sketches

Factor 1: View

Gallery View

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ideas that are already posted, and write the

number of the linked idea on the new sheet

8 Start a completely new sheet after reviewing

the posted ideas

For the first 10 minute period, each participant is given

a number of paper sheets and told to write down at

least two ideas on separate sheets of paper similar to

the “gallery view” condition At the end of the period,

the experimenter collects all sheets and systematically

redistributes them such that each participant views

each set of papers once Participants cannot identify

which one of their teammates had the sheets

previously In the four subsequent periods, lasting 7.5

minutes each, participants have the same options as in

the “gallery view” condition: to add ideas to an

existing sheet, to create a new product solution linked

to another sheet or to start a completely new product

solution The exception here is that participants focus

on the specific set of papers given to them at a

particular instance in time

Table 2 Experimental conditions and similar formal method

Experimental

(Aiken, et al., 1996)

2 6-3-5

3

4 C-Sketch

5 Gallery

6 Brainsketching

3.1.2 Rotational View Condition- Similar to 6-3-5 or

C-Sketch

For the first 10 minute period, each participant is

given a number of paper sheets and told to write down

at least two ideas on separate sheets of paper similar to

the “gallery view” condition At the end of the period,

the experimenter collects all sheets and systematically

redistributes them such that each participant views

each set of papers once Participants cannot identify

which one of their teammates had the sheets

previously In the four subsequent periods, lasting 7.5

minutes each, participants have the same options as in

the “gallery view” condition: to add ideas to an

existing sheet, to create a new product solution linked

to another sheet or to start a completely new product

solution The exception here is that participants focus

on the specific set of papers given to them at a

particular instance in time

3.1.3 Nominal Groups

For the nominal groups, individual were assigned to

work alone and were given the same amount of time

3.2 Factor 2: Representation

The second experimental factor prescribes how the participants communicate their ideas to other participants (words only, sketches only with no words,

or a combination of words and sketches) At the end of the sessions and after completion of the surveys, participants in either of the group sketches-only conditions labeled their sketches with brief descriptions to facilitate evaluation American mechanical engineers are typically not taught to draw free-hand and therefore their sketches are usually difficult to interpret without annotations The prior study (Linsey, et al., accepted) shows that the sketches only data shows a different pattern of results likely due

to the poor sketch quality and effort required by teammates to interpret the drawings For this reason, individual data was not taken and therefore no nominal groups

Boiling Water

Water Mill

by a Waterfall

Cam

Vertical Crushing Plate

Grate Hopper

Graduated Concentric Crushing Surfaces

Conveyor

Collection Bin

Hand Crank

Conveyor Drive

Grate

Fire

Water Inlet Hopper

Vertical Crushing Plate

Hopper

Fig 3 Set of examples which were briefly and accidently

shown in class to the nominal group participants

The nominal group data was taken two semesters after the group data was collected The same professor taught the class and the same experimenter collected the data During the semester the nominal group data was collected and prior to data collection, the participants in the nominal groups were accidently shown example peanut shelling machines (Fig 3) These ideas were only shown briefly in class and the participants’ data does not appear to be influenced The nominal groups were formed by randomly assigning the results from five individuals to a group and removing redundant results Data is from twenty-four individuals whose results were used to create forty nominal groups

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