C-Kano Model: A Novel Approach for Discovering Attractive Quality Elements

Transcription

1 C-Kano Model: A Novel Approach for Discovering Attractive Quality Elements Long-Sheng Chen 1 *, Cheng-Hsiang Liu 2, Chun-Chin Hsu 3, Chin-Sen Lin 4 * Corresponding Author 1 Department of Information Management, Chaoyang University of Technology, 168 Jifong E. Rd., Wufong Township, Taichung County, 41349, Taiwan, R.O.C. lschen@cyut.edu.tw 2 Department of Industrial Management, National Pingtung University of Science and Technology, 1, Shuefu Road, Neipu, Pingtung Taiwan, R.O.C. liuch@mail.npust.edu.tw 3 Department of Industrial Engineering and Management, Chaoyang University of Technology, 168 Jifong E. Rd., Wufong Township Taichung County, 41349, Taiwan, R.O.C. cchsu@cyut.edu.tw 4 Department of Industrial Engineering and Management, China University of Science and Technology, 245, Academia Rd., Sec. 3, Nangang District, Taipei City 115, Taiwan, R.O.C. cslin@cc.cust.edu.tw 1

2 ABSTRACT The theory of attractive quality (Kano model) can offer a better understanding of how customers evaluate products, and helps practitioners to focus on the most important quality attributes to improve. However, in practice, users of the Kano model usually cannot find an attractive or one-dimensional quality element due to an improperly-designed questionnaire, poorly-defined quality attributes or lifecycle of quality attributes. Dr. Kano also indicated that attractive quality creation to bring a must-be product back to an attractive product is a tough task. To solve these issues, this study proposed a novel Creativity-based Kano model (C-Kano model) which integrates the creativity techniques, TRIZ and SCAMPER, into the traditional Kano model. The proposed C-Kano model not only discovers customer needs, but also creates attractive quality elements. In this study, an actual quality survey of Massively Multiplayer Online Role Playing Game (MMORPG) was used to evaluate the effectiveness of the C-Kano model. Compared with the traditional Kano model, the experimental results show that our proposed model is superior in discovering attractive quality elements. Keywords: TRIZ, Kano analysis, attractive quality creation, SCAMPER, customer needs 2

3 1. INTRODUCTION The theory of attractive quality (Kano model) (Kano et al., 1984) is usually employed to discover the categories of customer needs (Chen and Su, 2006; Kuo, 2004). The Kano model can offer a better understanding of how customers evaluate a product, and assists companies with focusing on the most important attributes that need to be improved (Gustafsson et al., 1999). In recent years the Kano model has been widely and successfully applied in strategic thinking, business planning, product development, innovation, competitiveness, and product compliance (Huiskonen and Pirttila, 1998; Tan and Pawitra, 2001; Chen and Chuang, 2008; Lee et al., 2008). The Kano model shown in Figure 1 explains how the relationship between the degree of sufficiency and customer satisfaction with a quality attribute can be classified into five categories of perceived quality. They are attractive quality, one-dimensional quality, must-be quality, indifferent quality, and reverse quality. In a life cycle they start with indifferent, go to attractive, to one-dimensional, and then to must-be. This means that a quality that is seen as an attractive quality today, may be a must-be quality tomorrow. Some products may not follow this cycle. However, most importantly, we must be aware that the discovered quality category may vary with time. In addition, an attractive quality will definitely result in customers satisfaction. Therefore, how to create an attractive quality is a tough issue in the Kano model. Prof. Kano has indicated that attractive quality creation not only can bring a must-be or indifferent product back to being an attractive product, but it also can discover latent customer needs (Kano 2001). But, according to the literature, the Kano model lacks a systematic approach to instruct readers how to create attractive quality (Chen and Su, 2006; Kuo, 2004; Zhang and Dran, 2002; Yang, 2005; Witell and Lofgren, 2007). <Fig. 1 here> Moreover, when using the Kano model in practice, we might encounter the situation in which we cannot find any quality attribute that is attractive or one-dimensional. Sometimes, no quality categories can be found, except of an indifferent quality. This may be due to (1) improperly-designed questionnaire, meaning that the questionnaire items are ambiguous, unclear, or irrelevant. Survey responders may not be able to understand the intended objective; (2) poorly-defined quality attributes: Sometimes, a quality attribute is seen as non-attractive due to an inaccurate definition. For example, if we define the quality attribute as maintainability and users can receive updated service on time, then the responses to the survey will differ substantially from the attribute defined as users can easily maintain their systems without wasting extra time and money ; (3) the life cycle of 3

4 quality elements: The five quality elements of Kano model are in a life cycle. One quality element has been considered as attractive now, but it may be totally different next time. For example, 10 years ago, a remote controller was an attractive quality element for TV sets buyers, but is a must-be quality attribute today. We need an effective approach to create an attractive quality attribute. In order to solve these issues, this study introduced two famous creativity techniques, TRIZ (an acronym for the Russian word Teary Resheniya Izobretatelskikh Zadatch, which means Theory of Inventive Problem Solving ) and the SCAMPER checklist, to create attractive quality. By integrating creativity techniques into the traditional Kano model, this study created the novel Creativity based Kano model (C-Kano model) which not only determines customer needs, but also creates attractive quality. This work also provides an actual satisfaction survey of Massively Multiplayer Online Role Playing Game (MMORPG) to evaluate the effectiveness of our proposed model. Compared with the traditional Kano model, our experimental results show that our proposed C-Kano model is superior in discovering attractive quality elements. 2. TWO DIMENSIONAL QUALITY MODELS The Kano model is a useful tool to categorize product attributes based on how they are perceived by customers and their effect on customer satisfaction (Xu et al., 2007). Before introducing the Kano model, some of the literatures regarding the two dimensional quality models are employed in this study to discover customer satisfaction need to be addressed. The first is the Motivation-Hygiene theory (Herzberg et al., 1959) which also inspired Dr. Kano to present the Kano model. The Motivation-Hygiene theory studies people s psychological status regarding job satisfaction. In addition to its application in job satisfaction, Herzberg s theory has been adopted in consumer satisfaction studies. Later, Swan and Combs proposed the two-factor-theory of customer satisfaction which divides satisfaction into Instrumental Dimension and Expressive Dimension (Swan and Combs, 1976). In 1990, Ishikawa divided quality into two categories: backward-looking quality and forward-looking quality. Backward-looking quality refers to defects, flaws, and deficiencies (Ishikawa, 1990). Their existence will result in loss of customer satisfaction. Forward-looking quality refers to the positive characteristics of a product such as green and non-gene transforming, making it superior to the offerings of other companies. The fulfillment of these quality elements can increase customer satisfaction, although the quality which does not fulfill these elements is also acceptable. Following this kind of two factor categorization, Weihrich presented the concept of reliability factor and stability factor (Weihrich, 1994). Table 1 4

5 provides the summary of these two dimensional quality models. Above all, the Kano model is recognized as the best-known and most popular among them. <Table 1 here> In the Kano model, the product quality element of different categories that impact customer satisfaction is defined in different ways (Kano et al., 1984). According to the existing literature (Chen and Su, 2006; Kuo, 2004; Kano et al, 1984; Kano and Takahashi, 1979), they can be described as follows. (1) Attractive quality element This quality element will definitely result in customer satisfaction. Even if this quality is not obtained, it won t result in dissatisfaction. For example, when buying a low-priced car, a global positioning system may be considered as an attractive quality which can increase customer satisfaction. However, if the purchased car doesn t have this equipment, the customer can accept that, and it won t lead to dissatisfaction. (2) One-dimensional quality element A one-dimensional quality element results in satisfaction when fulfilled and results in dissatisfaction when not fulfilled (Kano et al., 1984). These quality elements are considered as the-more-the-better attributes. (3) Must-be quality element Must-be quality elements are taken for granted when fulfilled but result in dissatisfaction when not fulfilled (Kano et al., 1984). Customers expect these elements and thus view them as basics. (4) Indifferent quality element Customers do not care whether this element is present or not. (5) Reverse quality element The reverse quality element refers to attributes in which a high degree of achievement results in dissatisfaction. For example, a hot pepper will be viewed as a reverse quality, if the customer hates eating spicy foods. Although there are more than one two-dimensional quality models, we use the Kano model in this study for the following reasons. (1). Applying the Kano model can avoid two myths (Kano et al., 1984). They are: If we reduce product flaws or customer complaints, customer satisfaction will be increased and If we can add new functions to products or develop novel designs, customer satisfaction will be increased (2) The Kano model is suitable for determining the categories of quality expected by the customers. Besides, it also can help to identify and understand the lifecycle of quality element (Zhang and Dran, 2002). 5

6 (3) The Kano model can help researchers to understand the available information regarding their customers. In other words, it can be used to extract tacit knowledge of customers (Chen and Su, 2006). (4) In the development of products and services, the Kano model is an easy-to-use tool which can be utilized to obtain customers evaluation. Witell and Lofgren confirmed that the Kano model is a reliable approach and recommended readers to use this model to determine the needs of their customers (Witell and Lofgren, 2007). In addition, the many successful examples and works shown in Table 2 are another factor for employing the Kano model in this work. <Table 2 here> 3. CREATIVITY TECHNIQUES To create attractive quality attributes in the C-Kano model, creativity techniques are employed in this study. Among many creativity techniques, TRIZ is a systematic approach which a successor can step by step follow the procedure to generate ideas. SCAMPER checklist is a conventional technique and it has been used widely. Therefore, for the sake of simplicity and ease of use, this work employs TRIZ and SCAMPER to create attractive quality. These two techniques are introduced as follows. 3.1 TRIZ TRIZ (Altshuller, 1997) is an effective tool which was developed to help engineers find innovative solutions for technical problems. It works especially well in product design (Sakao 2007), service quality improvement (Su and Lin, 2006), product development processes, solving human factor problems in the manufacturing environment (Akay et al., 2007), and others (Yamashina et al, 2002; Akay et al., 2007). The founder of TRIZ, Genrich Altshuller, began work on his theory in 1946 and attempted to formalize methods of creative thinking which led to new inventions. Finally, he built a creative framework based on the study of approximately 2.5 million patents and focused primarily on mechanical design, observing trends in the evolution of technical systems (Altshuller, 1997). Today, TRIZ has been recognized as a widely popular subject concerning innovation in the technological field and it is being applied by many of the top 500 companies in the United States and Europe. It is a proven algorithmic approach to solve system problems and provides a systematic approach for innovation (Su et al., 2008; Su and Lin, 2006; Lau, 2004). TRIZ provides general solutions to a problem by considering different combinations of 40 principles in a 39 by 39 matrix consisting of 39 contradicting 6

7 parameters. The contradiction matrix, 40 invention principles and 39 parameters can be found in Appendix A, B and Table 4, respectively. A general model for TRIZ problem-solving is shown in Figure 2 (Domb, 1997). Although there are many techniques and methods in the TRIZ theory, the most popular one among them is the contradiction matrix. The procedure for using the contradiction matrix is as follows. Step 1: Define problem Define the elements of the design that must be improved. Step 2: Analyze problem Map the elements mentioned in step 1 into the terms of the 39 parameters (listed in Table 4) of the contradiction matrix. Step 3: Select parameters -Identify the solution directions that may help to resolve the problem. -Identify which elements in these solution directions are contradictory to the feature to be improved. Step 4: Find invention principles Map these invention principles into the terms of the 39 parameters of the contradiction matrix to obtain pairs of improving/worsening features. Then, use the contradiction matrix shown in appendix A to find the corresponding invention principles, according to the pair. Step 5: Develop and evaluate the feasible solutions Develop alternatives according to the corresponding invention principles and evaluate their feasibility. However, to clarify the procedure of implementing a contradiction matrix, this study provides an illustrative example in Section 4.2. In addition, readers can find more detailed information of TRIZ in (Domb 1997&1998; Altshuller, 1997; Lau, 2004; Akay et al., 2007; Su et al., 2008). <Fig. 2 here> 3.2 SCAMPER The SCAMPER (Eberle, 1971) checklist helps users to think of changes that will allow them to make an existing product into a new one. SCAMPER is an acronym that stands for words that are useful for being applied as a stimulus to make one think differently about a problem area. Usually, it is used to come up with fresh ideas. Users can use these changes either as direct suggestions or as starting points for lateral thinking. The letters in SCAMPER denote: S means substitute, including substituting components, materials, or people; C means combine, including mixing, combining, and integrating with other elements; A stands for adapt, to alter, to change function, or to use part of another element; M denotes modify, increase or 7

8 reduce in scale, change shape, or modify attributes; P means put to another use. For example, use a magazine as a fan to cool down; (6) E means eliminate, remove, simplify elements or reduce to core functionality; (7) R denotes reverse, turn inside out or upside down or use in reverse. Finally, it should be noted that options are not always mutually exclusive. For instance, using a magazine as a fan is both putting it to another use and also using it as a substitute. 4. THE PROPOSED C-KANO MODEL This section describes the procedure of the C-Kano model and provides an illustrative example to demonstrate the operation of our proposed methodology. 4.1 The procedure of the C-Kano model The implementation procedure of the proposed C-Kano model involves 6 steps, see Figure 3. In addition, the concise algorithm can be written as follows. Step 1. Define the quality attributes. Step 2. Construct the Kano questionnaire. Step 3. Collect data. Step 4. Check the results. IF the results are satisfactory (i.e. if you find attractive or one-dimensional quality), GO to step 6. ELSE GO to step 5. Step 5. Create attractive quality. <Fig. 3 here> Apply the TRIZ/SCAMPER technique to create attractive quality. Then use the created quality elements to redefine the questionnaire items. Finally repeat steps 1 to 4 till the users are satisfied. Step 6. Explain the results and draw conclusions. The C-Kano model contains 2 major phases, the Kano analysis (steps 1~4) and attractive quality creation (step 5). In the Kano analysis phase, we need to define the quality elements. Then, depending on these elements, we construct a Kano questionnaire. Next, this questionnaire is then employed to survey the needs of the customer. Finally, the results must be reviewed and checked to see if they are satisfactory or not. If we find enough attractive or one-dimensional quality elements, we will be able to explain the results and draw some conclusions. Otherwise, we go back to attractive quality creation (step 5). In phase 2, creativity techniques, TRIZ and 8

9 SCAMPER, are utilized to create new quality elements or redefine the description of the questionnaire items. The Kano analysis phase is repeated until sufficient attractive qualities are found. To clarify the whole process of the C-Kano model further, an illustrative example is provided next. 4.2 An illustrative example Let s take the quality element game pictures of an MMORPG as an example. Phase 1: Kano Analysis We start with the Kano analysis phase. First, we define the quality attribute of game pictures as the game pictures are smooth, of high-definition, and unique. According to this definition, we create two Kano style question items, as follows. Q1: How would you feel if the game picture IS smooth, of high-definition, and unique? (A)Like (B) Must-be (C) Neutral (D) Live with (E) Dislike Q2: How would you feel if the game picture IS NOT smooth, high-definition, and unique? (A)Like (B) Must-be (C) Neutral (D) Live with (E) Dislike These questions are then used to survey the customers opinions. Then, according to the answers and the Kano evaluation table (Table 3), we can determine the category of quality. For example, let s assume that the customer s answers to Q1 (functional) and Q2 (dysfunctional) are Like and Dislike, respectively. From table 3 we can then find that the element game pictures is considered as a One-dimensional quality. Unfortunately, in our survey, most (42.54%) customers think the quality of the game picture is an indifferent quality element. Only 14.93% of the samples considered it as an attractive quality. The different steps of the Kano analysis are shown in Figure 4. <Table 3 here> <Fig. 4 here> Phase 2: Attractive Quality Creation If we want to find the specific service attribute of the game picture which is attractive for customers, we need to go to the attractive quality creation phase shown as Figure 5. In this phase, creativity techniques are employed to solve our problem. Let s take TRIZ for example. <Fig. 5 here> 9

10 In this case, the process of using TRIZ in the attractive quality creation phase will be demonstrated after the 5 steps mentioned in Section 3.1 have been completed. Step 1: Define problem Most of the on-line games providers attempt to produce high quality game pictures which are realistic in a limited space (a monitor screen). A limited showing space is the main reason why we cannot display vivid, lifelike, or realistic pictures. No matter how much effort is made to create these game pictures, in the end they have to be displayed on a monitor screen. If game manufacturers can find a virtual reality solution for displaying pictures, it may be considered as an attractive quality by customers. Step 2: Analyze the problem In this step, we need to map displays game picture vividly with the terms of the 39 parameters in Table 4. As a result, the corresponding parameters (feature to change) could be volume of moving object (7). <Table 4 here> Step 3: Select parameters In this step, we need to identify the solution directions that may help remove the problem or determine which elements are in contraction with the feature to be improved (volume of moving object (7)). In this case, the manufacturing technology of virtual reality is a potential solution direction and can assist in removing the problem. Therefore, the undesired result (conflict) should be manufacturability (32). Step 4: Find invention principles According to the contradiction matrix in Appendix A, the suggested candidate principles are as follows. Principle 29 Pneumatics or hydraulics: Use gas and liquid parts of an object or system instead of solid parts (e.g. inflatable, filled with liquids, air cushion, hydrostatic, hydro-reactive). Principle 01 Segmentation: This principle has three interpretations. They are (a) Divide an object or system into independent parts; (b) Make an object or system easy to disassemble; and (c) Increase the degree of fragmentation or segmentation. Principle 40 Composite structures: Change from uniform to composite (multiple) structures. Step 5: Develop and evaluate feasible solutions In this step, we can develop alternatives based on the suggested principles, and 10

11 then evaluate their feasibility. These alternatives can be listed as follows. Alternative 1: Use the electronic fan to create airflow to increase the feeling of speed (Principle 29: Pneumatics or hydraulics). Alternative 2: Divide the game pictures from a monitor screen into independent objects. We can use 3D glasses to make game pictures more realistic (Principle 01: Segmentation). Alternative 3: We can combine the monitor screen with 3D glasses. Therefore a HUD (Head Up Display) could be the solution (Principle 40: Composite structures). After evaluating the feasibility of the 3 alternatives, alternative 3, HUD, is adopted. Then we go back to the Kano analysis phase to re-confirm whether the HUD is an attractive quality element or not. Confirmation ( 2nd time Kano analysis) Figure 6 summarizes the second implementation of the Kano analysis in order to double-check if what we found was an attractive quality or not. The question for the 2nd Kano analysis has been changed to How would you feel if the game pictures CAN (CANNOT) be displayed using a HUD (Head Up Display)? This time, most of the survey responders (51.43%) think the quality attribute game pictures is attractive. We successfully created and confirmed an attractive quality by using the C-Kano model. <Fig. 6 here> 5. IMPLEMENTATION 5.1 Define Quality Elements and Construction Questionnaire This section provides an actual case of on-line games customer satisfaction survey in order to evaluate the effectiveness of the C-Kano model. Based on a pilot survey, this study defines 17 quality elements, as shown in table 5. These elements are divided into two dimensions, product and service. In the product dimension, the quality elements include game pictures, sound effect, entertainment, storyline, roles, operation, secure exchange of virtual games, degree of difficulty of the game, the interaction between player and game, portability, maintainability and the help function. The service dimension focuses on packaging, promotion, price, the quality of trained game masters, and connection quality. Then, we can construct a Kano style questionnaire based on these elements. Some questions of the C-Kano model and the traditional Kano model can be found in Appendix C, which also provides examples of implementing TRIZ and SCAMPER. In addition, we also investigated the background of the players, including gender, age, education, occupation, available spending 11

12 money, desired way of charge, time spent on playing games, and motivation to play games. <Table 5 here> 5.2 The Collected Samples One hundred and fifty questionnaires were distributed, and 113 of them were returned. After removing incomplete samples, 105 of them were used for further analysis. From these participants, 69.59% were male. The majority of the participants ranged in age between 18~26 years old (81.91%); available spending money was less than NT 10,000 per month (78.09%). Of these players, 61.91% spent less than 5 hours playing games a day. But, about 23.81% of the players spent between 5~13 hours a day playing games, and 14.28% of the players spent over 13 hours per day. In desired way of charge, 75.68% players want to play free games. However, this still leaves 22.30% of the participants who want to pay their bill right away or after a short test time. Regarding motivation; 37.33% considered game content is the main factor for making their purchase decision. At the same time, advertisements (7.83%) and free factors (23.96%) influenced the purchaser, as did recommendations of peers (28.57%). Therefore, providing a free trial may be an effective way to promote a game, rather than spending lots of resources on advertising. 5.3 Results and Comparisons This section provides the experimental results and a comparison between the proposed C-Kano model and the traditional Kano model. Table 6 summarizes the results of the C-Kano model. In the proposed C-Kano model, 7 attractive and 3 one-dimensional quality elements were found. As shown in Table 7, compared with the results of the traditional Kano model which has only 2 one-dimensional (operation, the quality of GM) quality attributes and the possibility of determining a none attractive one,, the C-Kano model dramatically inreases the ability of finding attractive and one-dimensional quality attributes. As shown in Figure 7, it s evident that the C-Kano model outperforms the traditional Kano model in finding attractive quality. <Table 6 here> <Fig. 7 here> 6. DISCUSSIONS AND CONCLUSIONS In this study, in order to create attractive quality, we introduced the creativity 12

13 techniques, TRIZ and SCAMPER, into the traditional Kano model to propose a C-Kano model. An actual satisfaction survey of on-line games customers was provided in order to demonstrate the effectiveness of the C-Kano model. The experimental results indicate that the C-Kano model is superior in discovering attractive and one-dimensional quality elements. This is helpful for the manufacturers of on-line games when they want to develop an attractive product. From our experience of implementing creativity techniques, we note the following. First, TRIZ is more systematic than SCAMPER. Unlike SCAMPER, users of TRIZ can create innovative ideas in a step by step fashion. Second, when identifying an appropriate pair of features, users of TRIZ need to have a good understanding of parameters in a contradiction matrix, for which they are physical terms. Finally, it is suggested to users of TRIZ that they select more than one parameter if possible, because many columns in the contradiction matrix table are empty. In addition, we found that although TRIZ can create novel functions, some of these functions might not be acceptable by customers. Some novel quality attributes although viewed as indifferent today, may be viewed as attractive tomorrow. Therefore, before implementing the attractive quality creation phase of the C-Kano model, users should study the reasons why they cannot find an attractive quality right away. If the reasons are ill-designed questionnaire, ill-defined quality attributes or lifecycle of quality attributes problems, the C-Kano model is a very suitable tool. However, if the reason is that the quality attribute is too novel to be accepted by customers, then the C-Kano model does not provide any help. This finding may be a potential direction for future study. 7. ACKNOWLEDGMENT The authors would like to thank the National Science Council of Taiwan, R.O.C. for supporting this research in part under Contract No. NSC H MY2. REFERENCES Akay, D., Demiray, A. & Kurt, M. (2007). Collaborative tool for solving human factors problems in the manufacturing environment: the Theory of Inventive Problem Solving Technique (TRIZ) method. Intenational Journal of Production Research, 46(11), pp

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