Sensitivity Analysis of the Rating Scales and Worth Calculation Schemes Used in QFD Matrices

Design Engineering ◽

10.1115/imece2004-61500 ◽

2004 ◽

Author(s):

Shun Takai ◽

Kosuke Ishii

Keyword(s):

Sensitivity Analysis ◽

Quality Function Deployment ◽

Rating Scales ◽

Rating Scale ◽

Upper Bounds ◽

Specific Pattern ◽

House Of Quality ◽

Customer Requirements ◽

Design Concepts ◽

Concept Evaluation

Quality Function Deployment (QFD) is matrix method that identifies relative worth of product requirements from the customer requirements and their importance. Understanding the relative worth enables engineers to evaluate the potential of design concepts to achieve important requirements. In a QFD matrix called “House of Quality” or QFD I, engineers assess correlations between product requirements and customer requirements using a linear (e.g., 1–3–5) or an exponential (e.g., 1–3–9) rating scale. The exponential scale assigns product requirements that have large correlations with customer requirements a higher ratings of 9 instead of 5, and therefore, gives them larger relative worth. This paper studies how the choice of linear 1–3–5 and exponential 1–3–9 rating scales changes the relative worth of product requirements. To avoid being restricted to any specific pattern of a QFD matrix, this paper uses simulations and analytic approaches to obtain distributions of changes of relative worth, and to calculate the upper bounds of these changes. Finally, in an illustrative example, the authors integrate QFD and concept evaluation activities and provide a case in which the choice of rating scale in a QFD I matrix changes the optimal concept.

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Sensitivity Analysis of Relative Worth in Empirical and Simulation-Based QFD Matrices

Volume 5: 13th Design for Manufacturability and the Lifecycle Conference; 5th Symposium on International Design and Design Education; 10th International Conference on Advanced Vehicle and Tire Technologies ◽

10.1115/detc2008-49861 ◽

2008 ◽

Author(s):

Robins M. Kalapurackal ◽

Shun Takai

Keyword(s):

Cost Reduction ◽

Quality Function Deployment ◽

Development Process ◽

Rating Scales ◽

Rating Scale ◽

Calculation Scheme ◽

Product Development Process ◽

Customer Requirements ◽

Design Changes ◽

Simulation Based

Quality function deployment (QFD) is one of the most popular tools used in the product development process. It relates customer requirements to product requirements and enables engineers to determine which product requirement is more important than the others in satisfying customers. Some of the benefits of QFD are cost reduction, fewer design changes at the start of production, and improved communication among engineers. QFD applications use various approaches (i.e., worth calculation schemes and rating scales) to calculate the worth of requirements. The purpose of this paper is to study the change in the relative worth (normalized worth) of product requirements yielded by different rating scales and calculation schemes. We studied empirical and simulation-generated QFD matrices to determine how calculation schemes and rating scales influence the relative worth of requirements. Two representative scales and two calculation schemes are used to find the most and least sensitive cases, and the influence of the number of rows and columns in the relative worth of requirements. From the results, we identified the least sensitive and most sensitive combination of calculation scheme and rating scale. We also learned that QFD matrices become less sensitive to changes in rating scale and calculation scheme as the number of columns increases.

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Sensitivity of Relative Worth in QFD Matrices to Rating Scales and Worth Calculation Schemes: An Empirical Study

Volume 3: Design and Manufacturing ◽

10.1115/imece2007-42423 ◽

2007 ◽

Author(s):

Robins M. Kalapurackal ◽

Shun Takai

Keyword(s):

Cost Reduction ◽

Quality Function Deployment ◽

Rating Scales ◽

Rating Scale ◽

System Development ◽

Customer Requirements ◽

Journal Articles ◽

The Past ◽

Design Changes ◽

System Requirements

In the past several decades, Quality Function Deployment (QFD) has gained its popularity among engineers as a tool to relate (map) customer requirements (inputs) to system requirements or system components (outputs), and to calculate relative worth of these requirements and components. The benefits of QFD in system development include cost reduction, fewer design changes after the start of production, and improved communication among engineers. Despite the observed benefits, the needs for QFD research have been addressed by researchers. These research needs include decision-making process in QFD, rating scales used in QFD matrices, and calculation schemes for calculating the worth of outputs (e.g., system requirements) from the importance of inputs (e.g., customer requirements). The purpose of this paper is to empirically study sensitivity of the relative worth and rank of outputs in QFD matrices to rating scales and worth calculation schemes. We collected QFD matrices from journal articles and textbooks; then calculated the changes of relative worth and the rank of outputs when one type of rating scale and/or worth calculation scheme was changed to the other. The results suggest that the relative worth and rank of outputs are relatively insensitive to rating scales and worth calculation schemes in the QFD matrices studied in this paper.

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Penerapan Quality Function Deployment(QFD) Untuk Mengembangkan Kualitas Pelayanan Rawat Jalan Berorientasi Pelanggan Di Rumah Sakit Paru-Paru

Jurnal Ilmiah Kesehatan Media Husada ◽

10.33475/jikmh.v1i1.82 ◽

2012 ◽

Vol 1 (1) ◽

pp. 65-75

Author(s):

Rudy Joegijantoro

Keyword(s):

Fuzzy Logic ◽

Quality Function Deployment ◽

House Of Quality ◽

Customer Requirements ◽

Linguistic Terms ◽

Major Drawback ◽

Quality Function ◽

Structured Design ◽

Functional Features

Quality Function Deployment (QFD) is defined as a method that supports the structured design of products or services. The method is based on the customer needs and involves all the relevant parties within an organization that develops and produces a product through teamwork. It is a method for mapping and prioritizing customer requirements into functional features and technical modules to optimize market performance. Although the quality of a service can be dramatically improved through a QFD exercise, the traditional crisp scoring approach has a major drawback. A wrong conclusion can be easily produced since the fuzzy nature of linguistic correlation terms from evaluation members is ignored. To overcome this problem, fuzzy scoring for linguistic terms is proposed in this paper. This study integrates fuzzy logic into House Of Quality to establish a framework for prioritizing customer requirements to simply, objectively, and scientifically analyze service features.

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Integrating Concept Selection in a Software Development Process

10.1115/detc2008-49864 ◽

2008 ◽

Author(s):

Manoj Singiresu ◽

Kumar Boggavarapu ◽

Shun Takai

Keyword(s):

Software Development ◽

Product Development ◽

Quality Function Deployment ◽

Evaluation Criteria ◽

Software Requirements ◽

Customer Requirements ◽

Concept Selection ◽

Software Module ◽

Concept Evaluation ◽

Development Processes

Although a similarity between software and product development processes exists, concept selection is not treated as a core stage in software development whereas it is an important stage in product development. In this paper, we propose to apply concept selection methodologies in design engineering (modularized Quality Function Deployment (QFD) and perceptual concept evaluation methodologies) to software development. In particular, we demonstrate how these methods may be used for software architecture and software module concept selections. Modularized QFD matrices help software developers relate customer requirements to software requirements, and then to software module requirements. At the same time, importance of customer requirements is allocated to software requirements and then to software module requirements. These requirements and normalized worth serve as concept evaluation criteria and their weights. The proposed approach is illustrated using image search software as an example.

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A Framework for Design Traceability

Proceedings of the Human Factors Society Annual Meeting ◽

10.1177/154193129203600103 ◽

1992 ◽

Vol 36 (1) ◽

pp. 2-6 ◽

Cited By ~ 1

Author(s):

B. J. Barnett ◽

C. J. Arbak ◽

J. L. Olson ◽

L. C. Walrath

Keyword(s):

Human Factors ◽

Interface Design ◽

Quality Function Deployment ◽

Product Evaluation ◽

Design Tool ◽

Theoretical Research ◽

House Of Quality ◽

Design Concepts ◽

Design Engineers ◽

Design Solutions

Methods are needed for implementing findings of theoretical research early in the design phase and tracing them through to final designs. This paper describes one such approach in applying what is known about cognitive psychology, human factors, and development techniques to interface design. The basic technique used to provide a design framework was an adaptation of the Quality Function Deployment (QFD) house of quality. This paper describes the QFD structure and how it was adapted to provide that critical link between theoretical research findings and resulting interface design concepts. The discussion focuses on three topics: basic concepts within the house of quality, the house of quality adapted for interface design, and application to the design process. A number of benefits are realized from use of this approach. First, it describes directly the relationship between human processing characteristics, design requirements, and design solutions. Second, it characterizes the nature of conflicts among alternative design solutions. Third, it indicates areas of potential applied research. Finally, it provides a single, hierarchical construct that carries through from the initial conceptual design to final product evaluation. The benefit of this approach to interface design is that a broad spectrum of theoretical and experimental research is summarized into a manageable design tool, which may provide insights to human factors practitioners, design engineers, and subject matter experts alike.

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Integrating Target Costing Into Perception-Based Concept Evaluation of Complex and Large-Scale Systems Using Simultaneously Decomposed QFD

Journal of Mechanical Design ◽

10.1115/1.2336256 ◽

2006 ◽

Vol 128 (6) ◽

pp. 1186-1195 ◽

Cited By ~ 8

Author(s):

Shun Takai ◽

Kosuke Ishii

Keyword(s):

Quality Function Deployment ◽

Design Methodology ◽

Large Scale ◽

Target Costing ◽

Large Scale Systems ◽

Design Concepts ◽

Target Cost ◽

Conceptual Design Phase ◽

Concept Evaluation ◽

New System

In the conceptual design phase, engineers may need to perceptually screen and prioritize feasible design concepts by their potential to fulfill both customer and financial requirements. This paper presents a system design methodology that integrates perception-based concept evaluation and target costing of complex and large-scale systems. The methodology decomposes a system into modules and evaluates each module concept with its target requirements and cost. This method proposes the decomposition of quality function deployment matrices simultaneously for both requirements and structure in order to allocate the worth and target cost of the modules in a system. Developed from module concepts that satisfy their target requirements and cost, this new system should better satisfy both customer and financial requirements.

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Integration of Quality Function Deployment and Kano Model in Service Business

Jurnal Manajemen ◽

10.24912/jm.v23i3.572 ◽

2019 ◽

Vol 23 (3) ◽

pp. 411

Author(s):

Shafira Chaerunnisa Prasetyo, Budi Harsanto

Keyword(s):

Quality Function Deployment ◽

House Of Quality ◽

Customer Requirements ◽

Input Matrix ◽

Kano Model ◽

Quality Function ◽

Service Business ◽

Direct Observations

The purpose of this study is to determine the priority of customer requirements and technical responses for restaurants using the Quality Function Deployment (QFD) with the integration of the Kano Model. The data is collected through direct observations, interviews, and surveying of 150 respondents who are customers of restaurant B in Bandung. The data is analyzed by combining Kano Model with QFD in helping to build the first matrix in the House of Quality, namely the customer input matrix. This matrix together with other matrices forms a complete building of House of Quality. The findings show that there are six service attributes in a 'must-be' category. The two technical responses that should be prioritized for improvement because their importance level is above average are improvement of the facilities and maintenance of the facilities for the consumers. The two most highlighted facilities include a place of worship that is comfortable and clean, and a larger parking area.

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Sensitivity Analysis in Perceptual Evaluation of System Module Concepts

Volume 3: 19th International Conference on Design Theory and Methodology; 1st International Conference on Micro- and Nanosystems; and 9th International Conference on Advanced Vehicle Tire Technologies, Parts A and B ◽

10.1115/detc2007-35073 ◽

2007 ◽

Author(s):

Shun Takai ◽

Kosuke Ishii

Keyword(s):

Sensitivity Analysis ◽

Cost Estimation ◽

Imperfect Information ◽

Rating Scales ◽

System Development ◽

Development Stage ◽

Design Stage ◽

Perceptual Evaluation ◽

Concept Evaluation ◽

System Module

Selecting optimum concepts for a system and its subsystems in the conceptual design stage involves uncertainties due to imperfect information about customer preferences (market shares), cost of the system developed from each concept, and feasibility of new technology used in the new system. When analytical relationships between system performance and system inputs or parameters are unknown in the early system development stage, one approach to quantify the goodness of a concept is to use rating scales. This paper studies the effects of variations (precisions) in rating scales and in cost estimation for evaluating the goodness of system module concepts (e.g., sub-systems, assemblies, subassemblies, and parts). This paper presents a global sensitivity analysis (GSA) in perceptual concept evaluation, three probability measures for evaluating and selecting optimum concepts in GSA, and one-set-of-factors-at-a-time GSA to identify the sets of factors that cause significant variations in concept evaluation outcomes.

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Structured Brainstorming: A Method for Collecting User Requirements

Proceedings of the Human Factors and Ergonomics Society Annual Meeting ◽

10.1177/154193129303700507 ◽

1993 ◽

Vol 37 (5) ◽

pp. 427-431 ◽

Cited By ~ 9

Author(s):

Jani G. Byrne ◽

Todd Barlow

Keyword(s):

Quality Function Deployment ◽

User Requirements ◽

House Of Quality ◽

Customer Requirements ◽

Quality Function ◽

Product Experience ◽

Design Specifications ◽

The Core

This paper describes the Structured Brainstorming process employed by IBM's Networking Systems Customer Requirements department for collecting, analyzing, and deploying product requirements. Structured Brainstorming relies on the user's job and product experience to generate ideas for product requirements. Structured Brainstorming elicits these requirements from the users through a series of group and individual activities. After identifying the core ideas, users assign them priorities and assign satisfaction scores for current products. This information may be used to build a House of Quality (HOQ) within Quality Function Deployment (QFD) to organize and translate user requirements into design specifications. The authors offer guidelines and suggestions based on their experience with the technique.

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