Showing posts with label ratio scale. Show all posts
Showing posts with label ratio scale. Show all posts

14 August 2016

ISO 16355 Application Examples

Already some companies are implementing the key points of the new ISO 16355 standard.

Please join us in the upcoming 22nd International Symposium on QFD, September 9-10, 2016 to gain the first-hand knowledge on which companies are doing so, why and how they are implementing the modern tools prescribed in the new ISO rather than traditional methods, and what you need to know to stay competitive. Here are some of them:


QFD and the Systems Engineering Way of Working

image by wikipedia/Tosaka/Rolls Royce
This presentation will discuss the integration of Modern Blitz QFD® and Pathfinder, a Systems Engineering (SE) approach developed at Rolls Royce. In addition to the modern QFD tools such as Projects Goals Table, Customer Segment Table, Affinity Diagram, Hierarchy Diagram, AHP, and Maximum Value Table, the flow of Pathfinder tools such as Stakeholder Map / Context and Boundary Diagrams and Viewpoint Analysis are employed. The presentation will support the ISO 196355 standard to reference good practice and evidence of usage in industry.

Speaker: Steve Dimelow, QFD Green Belt®, Systems Engineering Specialist, Rolls-Royce plc., United Kingdom


Soft Systems Method Integration With Sustainable Energy Systems Development Using ISO 16355


Soft Systems Method Integration With Sustainable Energy Systems Development Using ISO 16355
The Soft Systems Method was developed by Peter Checkland's team at Lancaster University in the 1970s to help analyse complex situations or 'soft problems' where the problem for which a solution is sought is not clearly understood, or for which differences of opinion exist as to the precise nature of the problem. Such a 'soft problem' exists in the development of sustainable (economic and environmental) energy systems. This presentation will illustrate how modern QFD methods described in the 'ISO 16355 standard for QFD' have been used in the UK's Energy Technologies Institute to help in the analysis of the 'soft problem' of transition to low-CO2 energy systems. Illustrations will be given on how these methods can be used to establish system specifications and designs.

Speaker: Dr. Kim Stansfield, QFD Black Belt®, Senior Teaching Fellow, Warwick University WMG, United Kingdom


Using AHP In QFD - The Impact of the New ISO 16355 Standard


Traditional QFD uses ordinal weights-percentages of a total to describe priorities for customer's needs and technical solution approaches. AHP (Analytic Hierarchy Process), on the other hand,  works with profiles-vectors of unit length one, making it mathematically possible to add, substract and compare profiles. The ratio method proposed by Dr. Saaty to calculate priority profiles in AHP has been a part of Modern QFD for some time.
In fact, the new ISO standard 16335 suggests using the ratio scales and profiles in QFD, instead of the ordinal correlation strength indicators.

Not understanding how to properly apply AHP in QFD, however, could lead to project failures, especially if you are still using the traditional House of Quality matrix.  AHP is used in many steps in QFD, but this presentation will focus primarily on the House of Quality matrix.

Speaker: Thomas Fehlmann, Ph.D., Senior Consultant, Euro Project Office AG, Switzerland


ISO 16355 - Keeping Up with Global Best Practice


This presentation will outline the structure of the eight parts of the new ISO 16355, how they build on older QFD models from the 1970s and 80s, and what you need to do to become a leader and facilitator of this Modern QFD standard.

These include not only the classical House of Quality, but also more streamlined Blitz QFD®, strategic hoshin planning, competitiveness, project management, on-site customer visits, survey design, prioritization, quality assurance, innovation, cost management, reliability, optimization, supplier management, make and build, commercialization, support, retirement, and flow to next generation products.
New Product Development professionals will want to master these global best practices so they can engage their organizations in surging ahead of their competitors in creating the truly great products their customers demand.

Speaker: Glenn Mazur, QFD Red Belt®, QFD Institute, International Academy for Quality







22 May 2013

Can ordinal scale numbers kill you?

This May 19, 2013 article in USA Today might make you nervous. According to a study of 1400 sunscreen products by the Environmental Working Group, many continue to carry SPF ratings that some experts consider misleading and potentially dangerous. The reason, the article states is that:

(photo of sunscreens, source FDA)"SPF numbers like 100 or 150 can give users a false sense of security, leading them to stay in the sun long after the lotion has stopped protecting their skin. Many consumers assume that SPF 100 is twice as effective as SPF 50, but dermatologists say the difference between the two is actually negligible. 

"Where an SPF 50 product might protect against 97% of sunburn-­causing rays, an SPF 100 product might block 98.5% of those rays. There is a popular misconception that the SPF figure relates to a certain number of hours spent in the sun. However this is incorrect, since the level of exposure varies by geography, time of day and skin complexion."

In other words, people believe (as did I until I read this), that SPF numbers were ratio scale and that 100 provided twice the protection of 50. In fact, as this article postulates, they are ordinal and SPF 100 is only 1.5% more protection than SPF 50.

This is the problem with ordinal scales. They confuse people into interpreting numbers the wrong way.

QFD experts have known this problem for many years, and in our early days (1966-1985), we didn't have an easy solution to obtaining ratio scale values from subjective judgments. In the House of Quality (HoQ), rating customer needs or competitive performance on a 1-5 ordinal scale, or enumerating relationship weights using 1,3,5 or 1,3,9 ordinal numbers are examples of ordinal scale subjective judgments. Like SPF, you cannot meaningfully add, subtract, multiply, or divide them.

The solution to the problem came to us QFD folks in 1986 when Dr. Saaty's Analytic Hierarchy Process (AHP) became available as a PC program, allowing us to accurately convert subjective judgments into ratio scale values. It took me a few projects to see the difference in accuracy. For example, a judgment of "4" on the ordinal scale is usually perceived to be two times a judgment of "2."  But if you convert the 1-5 to ratio using AHP, it turns out that the judgment of " 4" is 26.0% and "2" is 6.8%.  26/6.8= 3.82 meaning that the judgment of a "4" is almost four times the judgment of a "2." Imagine the impact this mistake could have on a multi-million dollar project!

So, if you are not using AHP to calculate ratio scale judgments in your QFD, switch now, before the summer sun kills you.


AHP books by Thomas Saaty, Ph.D.