The aesthetic aspects, such as brand image, pattern, personal aesthetics, current trends of fashion and so on, play a crucial role in consumers’ perceptions of traditional crafts, thus Kansei information is essential and necessary for this evaluation problem. In addition, consumers’ preference information varies according to their character, feeling, aesthetic and so on.
In this section, we shall conduct a case study for Kansei evaluation of the traditional crafts in Japan to illustrate the Kansei evaluation model proposed in Chapter 7 as well as to provide a personified recommendation for the consumers. The consumers’ preferences on Kansei attributes consist of two parts:
1. Consumers’ preferences on the relation order on Kansei attributes.
2. Consumers’ preferences on the prioritization of Kansei attributes.
8.3.1 Identification of products to be evaluated: Kanazawa gold leaf
We will use the Kanazawa gold leaf, a traditional craft material with a history of over 400 years, as a case study to illustrate the proposed Kansei evaluation model. According to Association for the Promotion of Traditional Craft Industries, the introduction to Tradition Crafts in Japan are as quoted as follows4
The history of Kanazawa gold leaf can be traced back to the latter half of the Sengoku period (1428-1573), when Maeda Toshiie, the feudal lord of the Kaga clan governing the southern part of the area now known as Ishikawa Prefecture, sent a document back to the country from a campaign in Korea, explaining how to produce gold leaf. The Shogunate subsequently set up a gilders’ guild and controlled the production and sale of gold leaf throughout the country. After the Meiji Restoration in 1868, however, Kanazawa gold leaf workers took the opportunity on the abolition of governmental control to successfully develop both the techniques and extent of production. Being of such a high quality, Kanazawa maintains its position as the number one center for the production of gold leaf in the country.
The leaf is very thin and in the case of gold leaf is between 0.0001 mm and 0.0002 mm thick. For this reason, it is possible to apply the leaf to materials however complicated the pattern might be. What is more, none of the brilliance of the raw gold is lost at all, and the beauty and splendor of the finished products never cease to captivate the heart of the beholder. It still has a wide range of craft applications in the fields of textiles, lacquer ware, ceramics and on various types of screens, often applied to paper. It is also used on signs and individual carved characters as well as on the mizuhiki decorations for gifts and on the best art mountings. Large amounts of gold leaf in particular are used on household Buddhist altars and on shrine and temple buildings, too. The industry is sustained by 200 firms employing 1,000 staff, among whom they are 26 Master Craftsmen.
Within the framework of a research project supported by the local government, a total of thirty products of Kanazawa gold leaf have been collected for Kansei evaluation, as photographically shown in Fig.8.2.
4http://www.kougei.or.jp/english/crafts/1503/f1503.html
Figure 8.2: Thirty products of Kanazawa gold leaf used for Kansei evaluation
8.3.2 Identification of the subjects
A total of subjects, including relevant researchers of Kansei engineering, senior resi-dents in Kanazawa, and certified masters of traditional crafts, were chosen as subjects.
Among these 211 participants, 61.1% (129) were women and 38.9% (82) were men. The distribution of their ages is shown in Table 8.1. The ratio of men and women, as well as the approximate age data of evaluators were considered, trying to match the ratio in the general Japanese population, but the selection of ages from early twenties to latter half of sixties is especially due to those age groups being targeted as potential customers.
Table 8.1: Age distributions of subjects participating in the evaluation process Age Number of subject Percentage
20 to 29 56 26.5%
30 to 39 51 24.2%
40 to 49 51 24.2%
50 to 59 4 1.9%
≥ 60 49 23.2%
Total 211 100%
It should be noted that, in many studies of Kansei engineering, the number of subjects involved in experimental studies usually ranges from 10 to 35 [27, 85, 90, 91]. For pur-poses of our Kansei evaluation, such a small number of subjects may not provide enough information from various points of view, and may bring a statistical bias. To possibly reduce the subjectiveness of the assessments, a number of subjects, with a larger size, 211, were selected.
8.3.3 Identification and measurement of Kansei attributes
Before gathering Kansei assessment data of the 30 products of Kanazawa gold leaf by the 211 subjects, preliminary research was carried out to select Kansei attributes, by consulting with local manufactures and selling shops. Finally, 26 opposite pairs of Kansei words were selected through a brainstorming process. The bipolar Kansei words for the n-the Kansei attribute are represented as KWn=<KW−n,KW+n >, where n = 1,· · · ,26.
A 7 point scale was used to put a value each Kanazawa gold leaf with respect to each one of the Kansei attributes. In the literature, the point scale can be 5 point [92, 106], 7 point [102] or 9 point [53]. Choice of the odd point scale depends on specific problems.
The smaller the point scale is, the less differential semantics the Kansei attributes have.
As human perceptions are subjective and not objective, therefore the assessment pro-vided by the individuals are vague and uncertain. In such a case, linguistic descriptors are straight direct provided by the subjects to assess Kanazawa gold leaf. The fuzzy linguistic approach [163, 167] provides a systematic way to represent linguistic variables in a natural assessment procedure. It does not require a subject to provide a precise value at which an uncertain factor exists. Thus each Kansei attribute Xn is represented by a 7-scale linguistic term set Ln and triangular fuzzy numbers are used to denote the
linguistic variable, such that
Ln ={L−3n , L−2n , L−1n , L0n, L1n, L2n, L3n}
={ Very KW−n,KW−n, Fairly KW−n, Neutral , Fairly KW+n,KW+n, Very KW+n}
={(−3,−3,−2),(−3,−2,−1),(−2,−1,0),(−1,0,1),(0,1,2),(1,2,3),(2,3,3)} Table 8.2 shows the Kansei attributes with linguistic variables and triangular fuzzy num-bers, where Kansei words were used in Japanese at first and approximately translated into English in this study.
Table 8.2: Kansei attributes of traditional crafts, shown using linguistic variables and triangular fuzzy numbers.
Xn Left Kansei word 7-scale Kansei linguistic variable Right Kansei word KW−n L−3n L−2n L−1n L0n L+1n L+2n L+3n KW+n
X1 conventional unconventional
X2 simple compound
X3 solemn funny
X4 formal casual
X5 serene forceful
X6 still moving
X7 pretty austere
X8 friendly unfriendly
X9 soft hard
X10 blase attractive
X11 flowery quiet
X12 happy normal
X13 elegant loose
X14 delicate large-hearted
X15 luxurious frugal
X16 gentle pithy
X17 bright dark
X18 reserved imperious
X19 free regular
X20 level indented
X21 lustered matte
X22 transpicuous dim
X23 warm cool
X24 moist arid
X25 colorful sober
X26 plain gaudy, loud
8.3.4 Gathering Kansei assessments
Having identified the subjects and Kansei attributes, the next step is to gather the Kansei profiles of the thirty products of Kanazawa gold leaf. A total 211 population of subjects were invited to assess the thirty products of Kanazawa gold leaf in a simultaneous way. Each subject was given an answer sheet to rate the Kansei data for each Kansei attribute regarding each product. A sample answer sheet is given in Fig. 8.3 and the simultaneous process is shown in Fig.8.4.
Figure 8.3: A sample of the answer sheet in Japanese
Figure 8.4: Gathering data for evaluation of Kanazawa gold leaf