The investigation analysis of preference factor about
glasses design for women
Katsuo INOUE*, Chie NAKAMURA **, Kouki ITO****Hiroshima International University C/o Faculty of Human Environment 555-36 Gakuendai Kurose-chohigashi-hiroshima-shi Hiroshima 724-0695 JAPAN**Hiroshima International University C/o Faculty of Human Environment 555-36 Gakuendai Kurose-chohigashi-hiroshima-shi Hiroshima 724-0695 JAPAN***Holon Create Inc. 3-7-19 Shinyokohama Kouhoku-ku Yokohama-shi 222-0033 JAPAN,Abstract: Though a lot of glasses design for women are proposed and displayed in a shop recently,
it is difficult for a customer to select them. For the purpose, the fundamental research on what kindof glasses design is prefered from a viewpoint of a customer is thought to be required. Then, thepurpose of this research would analyze about the glasses design liked by women. As the methodof research, image words contributed to the attitude of likes the glasses design were calculated bymultiply regression analysis, and cognitive parts (form elements) affected to each image word of
the glasses design were extracted by rough sets. Before the calculation, these image words andcognitive parts were extracted by the evaluation grid method. Samples of seventy-one kinds ofglasses were evaluated into five steps about each image word on the subject of twenty women.
Four image words "foppish (fashionable), pretty, decent, intellectual" in twelve contributed
to liking were calculated using the data mentioned above. Next, the relationship between four
image words and cognitive parts was extracted based on the decision class using the data of each
image word. From the result, the hierarchical relation from the attitude to cognitive parts about
the preference has been clarified. Furthermore, the verification experiment of the result of thehierarchical relation was conducted on the subject of a designer working in a design office, who
proposed three design sketches reflecting the whole result of the attitude and emphasized pretty
and intellectual in it with some useful comments to improve the method.
Key words: Industrial design, Design evaluation, Rough sets

1. Introduction
Though many glasses designed by designers are displayed and sold in the shop of glasses today, consumers
have a lot of labors to search the product suitable for likes out of these many glasses. Glasses are therepresentation of limited production of diversified products from a few composition elements, and also havevery sensitivity as a product. Therefore, the maker of glasses mainly performs the policy that consumers
chose the product suitable for likes from these many various glasses with which the maker provides them.
However, the research on the preference of a consumer is few. The result of the hearing investigation to glasses
maker conducted in July 2004 has showed that research on the design harmonized with a face was mainly
and quantitative research on the taste factor of the design from a view of consumers is very few as the result
supporting the above mention. Moreover, the opinion from the selling side that the glasses design suitable forCriterion
variable

Multiply regession
analysis
Rough sets &analysis methodof decision rules

prefer, be satisfied
be attracted, ....

Attitude

Individual differenceis large.

modern, individual
pretty, high-grade, ...

Image
Cognition

It looks round,square, large, ...

Form elements

round shape,square shape, ...

Individual differenceis small.

Explanatory
variableFig.1 Class relation of analytic process in the researcha face is not necessarily selected was also obtained. Therefore, it is found that a consumer's taste is also animportant element for the preference of a glasses design.
Then, in this research, the taste factor of a glasses design is quantitatively analyzed using Kansei Engineering
technique. Moreover, verification and the subject of the analysis result would be considered by the experiment
designing glasses conducted on a designer working in the office using it.

2. The analytic method
The fundamental view of Kansei Engineering related especially with a product design is reducing affective"attitude" or "image" of man to concrete "form elements" (Physical quantity) which can be used as knowledgeof a design. This relation can be hierarchically illustrated as shown in the left-hand side of Fig.1. As shown in
the right-hand side of Fig.1, a reverse problem will be solved as the relation between the criterion variable of theattitude or the image and the explanatory variable of the form element from an analytical viewpoint. In addition,
an image may not exist depending on goods.
This class relation has the feature that individual difference is decreasing from a higher rank to a lowerrank. That is, it is the analysis method of Kansei Engineering to solve a relation from the upper rank with large
individual difference to a lower rank with little individual difference. Also as knowledge of a design, this classrelation is effective. Moreover, it can be said that the accuracy of the reverse problem via "image" in the middle
becomes high , rather than the reverse problem of “cognitive part" directly from "attitude" is solved.
Therefore, in this research, the relation between the attitude and the image is calculated by multiply regression
analysis in the procedure shown in the left-hand side of Fig.1, and the relation between the image and thecognitive part is calculated by both rough sets [1] and the analysis method of decision rules we proposed [2][3],from which the research applied to Kansei Engineering began these days. In addition, evaluation words of theattitude and the image and cognitive parts are extracted by the evaluation grid method proposed by Sanui.

3. Extraction of evaluation words and cognitive parts
Though how to extract evaluation words is a general method to select and arrange the reference related tothe target product, it is a specialist’s viewpoint and it is possible to differ from a consumer’s viewpoint. Then,the evaluation grid method that is a method of clinical psychology has been used. On the other hand, althoughTable 1 Cognitive parts of the glasses
Category

Item
1

Material

Plastic (A)Metal (B)Tortoiseshell (C)2Frame pattern

Edge (D)No edge (E)Pair (F)

Nylon (G)Reverse Nylon (H)Big (I)Middle (J)3Whole form

4

Top of lens

(L)

(M)
linear R

5

Slim (K)(N)
Curve(O)
CircleV characters

Bottom of lens
(P)

(Q)

(R)

(S)

6

Lens pattern

Uniform (T)Spread (U)Narrows (V)7

BridgeOne bridge (W)Top continuation (X)Peculiarity (Y)8Design ofjoint portion

It is. (a)Nothing (b)9Side pattern

Portion (c)Unity (d)Decoration (e)10 Frame color

Gold (f)Silver (g)Red system (h)Feature color (m)Pattern (n)Dark brown (k)[ Yellow, green, blue ]11 Color ofear portion

Red system (r)Black system (s)Feature color (u)Pattern (w)White (t)[ Yellow, green, blue ]extracted "form elements" from the form classification in many cases, it is apprehensive to extract portions thata consumer does not recognize as form elements. Therefore, in this research, cognitive parts were defined asform elements that consumers can recognize. In October 2004, the evaluation grid method was conducted on
five female students using 71 kinds of glasses sample photographs taken in the glasses shop. Consequently, oneattitude word "likes", twelve image words, and cognitive parts of eleven items shown in Table 1 were extracted.

4. Related analysis between an attitude and an image
First, thirteen words of the attitude and the image extracted in the preceding chapter were evaluated into five
steps to twenty female students using the questionnaire shown in Fig.2 for multiply regression analysis. And
average value of twenty subjects about each evaluation word was calculated based on the evaluation data (71kinds of samples x 13 evaluation words x 20 subjects). Next, image words (the explanatory variable) contributed
to the attitude of likes (the criterion variable) were calculated by multiply regression analysis. The result isshown in Fig.3. The result of official approval was also satisfactory. In addition, , "novel" of high correlation
Sample No.1

partical regression coefficient

0.5
foppish (fashionable)
novelsafe

foppishnot foppish

intellectual

not intellectual

individual

not individual

likedislikeprettynot pretty

high-grade

not high-grade

decentsimplemodernretrogentle

not gentle

complicatedsimplehard to breakeasy to breakfemininemasculine

0.4
0.3
0.2

intellectual

prettydecentdurablemodern0.1

gentle0
not high-grade-0.1

simplemasculine

not individual-0.2

multiple correlation coefficient : 0.91

Fig.2 Questionnaire of an attitude and images

Fig.3 Result of multiply regression analysis

with "foppish" was deleted from examination of Multicollinearity. As shown in Fig.3, it is found that glasses
design with images of very foppish, pretty, decent and intellectual is loved more from a view of four image
words strongly contributed to the attitude. In addition, these four evaluation words are used also for rough sets
and the analysis method of decision rules after the following chapter.

5. Related analysis between an image and a cognitive partAs the criterion variable, each quantitative data of four images greatly contributed to an attitude used bymultiply regression analysis calculation of the preceding chapter was classified into three decision classes. On
the other hand, as the explanatory variable, each sign of the category for every item shown in Table 1 is assignedin accordance with the content of each sample. The decision table with the criterion variable of "foppish"is created by this procedure. Each other decision tables of "decent", "pretty" and "intellectual" were createdsimilarly. Next, rough sets were calculated from these four decision tables, and decision rules of each image
were obtained. The result calculated by the analysis method of decision rules was visually expressed intelligibly
based on those each decision rules as shown in Table 2.

6. Discussions
Each design specification of the glasses of four images can be read in the conclusion of Table 2. If the attitude
is searched for by use of the class relation shown in Fig.1 based on this result, from the right end of Table 2,The glasses liked by the female college student would be the half rim frame design of a somewhat smaller metalmaterial, the top of its lens with a curve, the bottom of its lens with a linear R or a circle, the lens pattern witha uniform or a little spread, the white side pattern in a portion, and mainly a gold or silver frame. As this resultsummarized the contents of a glasses design loved best at the time of the investigation, this result of the classrelation from the attitude to the cognitive parts shown in Table 2 becomes the precious data when performing
new design trials, such as idea emphasized prettiness more or reversing the ranking of the important degree of animage. Then, the verification experiment aiming at the above was conducted on a designer working in the office.

Table 2 The conclusion of analysis results from images to cognitive parts about the attitude
FoppishPretty

0.442

0.209

Decent IntellectualPrefer

PlasticAB
MetalTortoiseshell CEdge
DNo edge
E
2 Frame pattern
PairFNylon
GReverse Nylon HBigI
3 Whole formMiddle
JSlimK
linear RLCurve
M
4 Top of lensCircleN
V characters Olinear R
PCurveQ
5 Bottom of lensCircleR
V characters S
UniformT
6 Lens pattern
SpreadU
Narrows
V
One bridgeW
Top continuation X
7 Bridge
Peculiarity
Y
It is.
a
8 Design of joint portion Nothing
bPortioncUnityd
9 Side pattern
Decoration
eGoldfSilverg
Red systemh
10 Frame color
Dark brownkFeature color mPatternnRed systemrblack system sWhitet
11 Color ofFeature color u
ear portion
Patternw
1 Material

The degree of much consideration of an image（Partial regression coefficient）

0.165

0.163

Inconsistency item

7. Verification experiment
In order that this result may verify whether it is utilizable for the proposal of an actual design, the verification
experiment in November 2004 was conducted. The concrete contents of an experiment are as follows. First, after
the designer observed the glasses in the hand in shops in advance, detailed explanation was given to the designer
about the contents of the conclusion mentioned the preceding chapter. And it requested to him that a design plan
was decided based on these contents of explanation and some idea sketches were created. As the result of thisexperiment, the designer presented idea sketches and comments from three viewpoints shown in Table 3.(1)Though it is not difficult to design based on the composition (configuration) of the glasses of the shown analysis
result for the sake of the simple composition, it can become an average design. Fundamentally, it is considered tobe dependent on a designer's capability what kind of design is carried out based on the analysis result.
(2) As for the glasses design, not only an overall configuration but also expressing an image by the partial
ornament and plastic processing in details is possible, so that it is a subject how far it is obtained by analysis.
(3) Since the analyzed result is the structural class relation, as design knowledge of the design at the time ofconsidering a design concept and design specification, it can be effective by discussing this relation flexibly.
From the above mention, though this analysis result can be used as knowledge of the design for the actual
design to some extent, it is shown that further improvement is needed.
Table 3 The example of he proposal design by the verification experiment
Plan and concept

Sketch proposal

Explanation
The proposal expressing(1) Basic principles of sketch :the attitude of "liking":

After the form of the outline of a lens isdetermined as the most important point,

A sharp image is directed with the lensform spreading outside.
The proposal fulfilled conditions
altogether mostly.
B,G,K,M,P,T,W,b,c,g,t

the frame form is made according to it.
(2) The whole concept common to
three proposals :The proposal emphasized "pretty":a) Simple configuration without unnecessary
ornaments and patterns to the frameb) Molding expressed foppish (fashionable)

The design considered the balancein respect of practical use, with a little
large view of a size and the size ofthe degree of middle.
"Pretty" is directed by a red colorand roundness.
A,D,J,M,R,T,X,b,d,h,rand decent based on pretty(3) The added concept :The design expressed beauty and composure
which is not conspicuous too much, while
making much of positioning as accessories

The proposal emphasized "intellectual":
The design not spoiled sharp image by
its slim, in spite of a lens with big roundness.
As a whole, smartness is directed by
the gold frame and the unity in the side pattern.
B,G,K,M,R,T,W,b,d,f,s

8. Conclusion
In this research, first of all, the evaluation word (the attitude and image) and the cognitive part of glasses
using 71 kinds of glasses samples were extracted. And the evaluation words were evaluated into five steps, andthe average value of each sample and the decision class used by rough sets were calculated. The class relationof the attitude, the image and the cognitive part shown in Fig.1 were clarified based on the calculated value.
Consequently, four images strongly contributed in an attitude were obtained. As the result of considering by
rough sets and the analysis method of decision rules based on four images and the decision class of cognitive
parts of the glasses shown in Table 1, the class relation of Table 3 was obtained quantitatively. We had a designer
verify whether this analysis result can utilize for the proposal of the actual design based on this result. Throughthe verification experiment, this research shows that the result is possible enough to use as design knowledge
when designing glasses. Moreover, it was indicated not only that there is some room of improvement for a new
design but also that the information on molding and the ornament of details is insufficient.

References[1] Z. Pawlak, 1982, Rough Sets, Internet. J. Inform. Computer. Science, Vol.11, No.5, pp. 341-356.
[2] K.Inoue, M.Hirokawa, 2003, Proposal of related analysis between Kansei words and Cognitive form,
Bulletin of International Rough Set Society, Volume 7, No. 1/2, pp. 55-59.
[3] Katsuo INOUE, Yuki YAMAZAKI, Akira OKADA, 2003, Proposal of New Analysis Method Using RoughSets for Design Evaluation, Journal of the 6th Asian Design Conference International Symposium on Design
Science, E-18(CD-R).

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