Quality Function Deployment Acknowledging: David Menks Anwar Ahmed

Quality Function Deployment Acknowledging: David Menks Anwar Ahmed Kaijun Fu ound at: http://sern.ucalgary.ca/ kjfu/courses/SENG613/teamwork.html 1

Other Sources on QFD/SQFD Good overview can be found at: http://pages.cpsc.ucalgary.ca/ johnsonk/SENG/SENG613/Project/rep ort.htm Downloadable tool: www.iti-oh.com SQFD paper: (see other slides) Nov 23, 2000 SENG 613 QFD 2

Table of Contents Overview QFD: Step by Step Exercise Comparison of Different RE Techniques Application of QFD on Software Engineering QFD software list Discussion Nov 23, 2000 SENG 613 QFD 3

Overview of QFD The History of QFD. What is QFD? Why use QFD? Characteristics of QFD? Nov 23, 2000 SENG 613 QFD 4

History of QFD 1960’s, Yoji Akao conceptualized QFD. Statistical Quality Control, SQC, was the central quality control activity after WWII. SQC became Total Quality Control, TQC. QFD was derived from TQC. Nov 23, 2000 SENG 613 QFD 5

First Application of QFD 1966, Bridgestone Tire Corp first used a process assurance table. 1972, the process assurance table was retooled by Akao to include QFD process. 1972, Kobe Shipyards (of Mitsubishi Heavy Industry) began a QFD Oil Tanker project. 1978, Kobe Shipyards published their quality chart for the tanker. Nov 23, 2000 SENG 613 QFD 6

QFD Takes Hold The first paper on QFD was published in 1972. In 1978, the first book on QFD was published in Japanese. In 1983, the first English QFD article was published in North America. By the late 1970’s most of the Japanese manufacturing industry were using QFD. Nov 23, 2000 SENG 613 QFD 7

QFD in North America QFD spread rapidly in North America during the 1980’s The Automobile industry and Manufacturing began heavy use of QFD at this time. QFD symposiums (North American, Japanese, European, International) were set up to explore research relating to QFD techniques. The QFD institute was formed in 1994. Nov 23, 2000 SENG 613 QFD 8

QFD in Software Engineering The QFD Research Group was seeking research relating to QFD in Software Engineering since 1987. A new style of QFD, Software QFD (SQFD), has emerged. DEC, AT&T, HP, IBM and Texas Instruments have all published information relating to SQFD (Haag, 1996). Nov 23, 2000 SENG 613 QFD 9

Additional Techniques There are many techniques which are a style of QFD or are used to enhance QFD. These include: TRIZ, conjoint analysis, the seven product planning tools, Taguchi methods, Kano model, SQFD, DQFD, Gemba, Kaizen, Comprehensive QFD, QFD (N), QFD (B). Nov 23, 2000 SENG 613 QFD 10

Overview of QFD The History of QFD. What is QFD? Why use QFD? Characteristics of QFD? Nov 23, 2000 SENG 613 QFD 11

What is QFD? Quality Function Deployment, QFD, is a quality technique which evaluates the ideas of key stakeholders to produce a product which better addresses the customers needs. Customer requirements are gathered into a visual document which is evaluated and remodeled during construction so the important requirements stand out as the end result. Nov 23, 2000 SENG 613 QFD 12

The QFD Paradigm QFD provides the opportunity to make sure you have a good product before you try to design and implement it. It is about planning and problem prevention, not problem solving (Eureka, 1988). QFD provides a systematic approach to identify which requirements are a priority for whom, when to implement them, and why. Nov 23, 2000 SENG 613 QFD 13

High-Level QFD Requirements are initially elicited using other RE techniques (interviewing, brain-storming, focus-groups, etc). QFD involves the refinement of requirements using matrices and charts based on group decided priorities. There are 4 Phases of QFD. Each Phase requires internal iteration before proceeding to the next. Once at a Phase you do not go back. Nov 23, 2000 SENG 613 QFD 14

What Does QFD Require? QFD requires time, effort, and patience. QFD requires access to stakeholder groups. The benefits of QFD are not realized immediately. Usually not until later in the project or the next project. QFD requires full management support. Priorities for the QFD process cannot change if benefits are to be realized. Nov 23, 2000 SENG 613 QFD 15

Overview of QFD The History of QFD. What is QFD? Why use QFD? Characteristics of QFD? Nov 23, 2000 SENG 613 QFD 16

Why use QFD? The QFD process leads participants to a common understanding of project direction and goals. QFD forces organizations to interact across their functional boundaries (Hales, 1995). QFD reduces design changes (Mazur, 2000). Nov 23, 2000 SENG 613 QFD 17

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QFD Artifacts Prioritized list of customers and competitors. Prioritized list of customer requirements. Prioritized list of how to satisfy the requirements. A list of design tradeoffs and an indication of how to compromise and weigh them. A realistic set of target values to ensure satisfaction. Nov 23, 2000 SENG 613 QFD 19

What about Cost? Cost reduction is not mentioned as a ‘Why to use QFD’. Initial costs will be as high or a little higher compared with traditional techniques. You are seeking long term savings in that product or the products that follow. Nov 23, 2000 SENG 613 QFD 20

Overview of QFD The History of QFD. What is QFD? Why use QFD? Characteristics of QFD? Nov 23, 2000 SENG 613 QFD 21

Characteristics of QFD 4 Main Phases to QFD Product Planning including the ‘House of Quality’ (Requirements Engineering Life Cycle) Product Design (Design Life Cycle) Process Planning (Implementation Life Cycle) Process Control (Testing Life Cycle) Nov 23, 2000 SENG 613 QFD 22

QFD Phase 1 Phase 1 is where most of the information is gathered. Getting good data is critical. Any mistakes in requirements here will be magnified later. Software Engineers should spend most of our time in this Phase. Nov 23, 2000 SENG 613 QFD 23

The House of Quality (HoQ) Is a set of matrices which contains the requirements (What’s) and the detailed information to achieve those requirements (How’s, How Much’s). Stakeholder groups fill in the matrices based on their priorities and goals. A key to the HoQ is making sure each group answers the same question about the same relationship, What vs How, cell. Nov 23, 2000 SENG 613 QFD 24

Key Items to Address in HoQ QFD Team Mission Statement. Who is the customer? What are the Requirements? How important is each requirement? How will you achieve each requirement? Complete the Relationship Matrix (what’s vs how’s). Which how’s are the most important? What are the tradeoffs between the how’s? What target values should be established? Nov 23, 2000 SENG 613 QFD 25

QFD: Step by Step Guide How QFD Works Step by Step Guide to Build a “House of Quality” Example: Web page development Nov 23, 2000 SENG 613 QFD 26

How QFD Works Customer-requirements-driven design and production planning process Rationale is that product quality is measured by customer satisfaction and customers are satisfied if their needs or requirements are met QFD is building requirements into products. Inputs customer requirements Outputs production procedures for producing a product to satisfy customers. Nov 23, 2000 SENG 613 QFD 27

How QFD Works (2) Require ments Concei ve Technic al Specific ations Design High Level Desig n Process Meth ods Tools Product ion Procedur es QFD Planning Process Nov 23, 2000 SENG 613 QFD 28

House of Quality Correlation Matrix (Hows vs. Hows) Technical Specifications (Hows) Customer Relationship Requirements Matrix (Whats) How muchs Nov 23, 2000 (Whats vs. Hows”) Technical Competitive Target Goals Evaluations Degree of Technical Overall Importance Difficulty Ratings Whys Customer Customer Market Importan Evaluation ce (Whats vs. Whys) Rating SENG 613 QFD Example 29

Customer Requirements "Voice of Customer” (VOC) Are “whats” Expressed in customer’s own language Qualitative, vague, ambiguous, incomplete, inconsistent Group session Categorization and organization Nov 23, 2000 SENG 613 QFD 30

Technical Specifications Voice of the Engineers or Designers (“hows”). Interpretations of "whats" in terms of technical specifications or design requirements (designers’ language) Potential choices for product features Each "whats" item must be converted (refined) to “how(s)” They have to be actionable (quantifiable or measurable) Free of technology and implementation creates flexibility for design Nov 23, 2000 SENG 613 QFD 31

Relationship Matrix “Whats” vs. “Hows” Correlates how “hows” satisfy “whats” Use symbolic notation for depicting weak, medium, and strong relationships A weight of 1-3-9 or 1-3-5 is often used More “strongs” are ideal Cross-checking ability Nov 23, 2000 SENG 613 QFD 32

Customer Prioritization Prioritizing the importance of each “whats” item to the customer. Rate each “whats” item in 1 to 5 rating Completed by the customer AHP can be used Nov 23, 2000 SENG 613 QFD 33

Customer Market Competitive Evaluations Comparison of the developer's product with the competitor’s products Question: “Why the product is needed?” The customer evaluates all products comparing each “whats” item Rating of 1 of 5 is given The results help position the product on the market. Identify the gaps Nov 23, 2000 SENG 613 QFD 34

Target Goals “How much’s" of the “Hows“ (measurement) Answers a common design question: "How much is good enough (to satisfy the customer)?“ Not known at the time when the "hows" are determined. They are determined through analysis. Clearly stated in a measurable way as to how customer requirements are met Provides designers with specific technical guidance Can be used for (acceptance) testing. Nov 23, 2000 SENG 613 QFD 35

Correlation Matrix “Roof” part Identifies how “hows” items support (positive) or conflict (negative) with one another May combine strong positive items to reduce development effort Find trade-offs for negative items by adjusting “how much” values. Trade-offs must be resolved or customer requirements won’t be fully satisfied. Nov 23, 2000 SENG 613 QFD 36

Technical Specifications Competitive Evaluation Similar to customer market competitive evaluations but conducted by the technical team Technical advantages or disadvantages over competitor products Conflicts may be found between customer evaluations and technical team evaluations Nov 23, 2000 SENG 613 QFD 37

Technical Difficulty Assessment Performed by technical teams Helps to establish the feasibility and realization of each "hows" item 1 to 5 ratings Nov 23, 2000 SENG 613 QFD 38

Overall Importance Ratings Only time when math is required Calculated overall ratings Function of relationship ratings and customer prioritization ratings. Used to determine a set of technical specifications / requirements needed for the next phase. Nov 23, 2000 SENG 613 QFD 39

Decisions for Phase 2 The “Hows” are analyzed Overall importance ratings Technical difficulties Competitive ratings Decisions on design requirements are made Start product design phase Nov 23, 2000 SENG 613 QFD 40

SQFD QFD for software Software Engineering is requirements driven Addresses quality issues in software development Usually use QFD phase 1 Focuses on requirements “Hows” vs. functional or non-functional requirements “How much’s” vs. Testing Nov 23, 2000 SENG 613 QFD 41

How to Apply QFD to SE Use for new or upgrade type of projects Requirements refinements Customer has ideal, developer has solution Ideal to know application domain knowledge Software for internal use Software for general use such as OS, word processor etc. Nov 23, 2000 SENG 613 QFD 42

Presentation Summary Disadvantages of SQFD Advantages of SQFD How to Make SQFD work Nov 23, 2000 SENG 613 QFD 43

Disadvantage of SQFD - What Makes QFD Unsuitable for SE Time and resources consuming Process limitation in iteration support Does not support common language between users and developers Documentation requirements Focus on quality other than functionality Nov 23, 2000 SENG 613 QFD 44

Benefits of SQFD Communications among groups Decision justification Metrics Cross-checking Avoid loss of information Shortens the SDLC Source: http://www.acm.org/pubs/articles/journals/cacm/1996-39-1/p41-haag/p41-haag.pdf Nov 23, 2000 SENG 613 QFD 45

Advantages of SQFD Customer / User involvement Focus on customer needs Team builder Improve product or service quality Shorter development cycles Lower costs and greater productivity Nov 23, 2000 SENG 613 QFD 46

Advantages of SQFD (2) Reduces design changes Good for communication, decision making and planning Allows for a lot of information in a small space Nov 23, 2000 SENG 613 QFD 47

How to Make SQFD Work Obtain management commitment Establish clear, up-front objectives Strong technical know-how Establish multi-functional team. Designate a facilitator QFD training Nov 23, 2000 SENG 613 QFD 48

How to Make SQFD Work (2) Get an adequate time commitment from team members Schedule regular meetings Avoid first using QFD on a large, complex project Avoid gathering perfect data Avoid technical arrogance Focus on the important items Nov 23, 2000 SENG 613 QFD 49

Conclusion QFD originated in the Manufacturing industry and has been applied to software engineering QFD addresses the quality of the product SQFD is QFD for software QFD, JAD, SSM, PD, RAD and OO all have their merits and faults The use of the technique depends on the project Nov 23, 2000 SENG 613 QFD 50

QFD vs. JAD QFD Type Group session approach Goal Clients quality need Driving force Customer voice Defect Prevention Nov 23, 2000 Suitable SENG 613 QFD J AD Group session approach Improve the system Human communication Suitable 51

QFD vs. JAD cont. QFD Communication/ Cooperation 10000 users [Capers J ones, 1995] Nov 23, 2000 J AD Software Users & personnel & developers their users No such Not suitable limitations SENG 613 QFD 52

QFD vs. JAD cont. QFD J AD Focus House of quality Proper communication Fail Lack of support Automated tools are not of Top well & facilitator management bypassed Nov 23, 2000 SENG 613 QFD 53