An affinity diagram is a tool that is used to organize a large number of ideas, opinions, and issues and group them based on their relationships. Affinity diagrams are generally used for categorizing ideas that are generated during brainstorming sessions and can be particularly useful for analyzing complex issues.
The steps for creating an affinity diagram can include:
It uses a planning matrix to define the relationship between customer requirements and the capability of the product and the company to satisfy these requirements. Because this matrix looks like a house, where customer requirements and product attributes resemble the main living quarters, competitive analysis resembles the porch, and the correlation matrix resembles the roof, it is called House of Quality.
It starts with customer requirements. The customers for a product or service are identified and their requirements from the product or service are gathered using different tools such as focus groups, surveys, and customer experiences. A structured list of customer requirements is then drawn by analyzing and organizing this data using tools such as affinity diagrams and tree diagrams.
Importance ratings are used for quantify the customer requirements and rated according to their importance on a scale of 1 to 5. This rating will be used in the relationship matrix at a later stage.
Another element is the Competitive analysis where customers views about the competition are gathered through research to provide a better understanding of the market. Here, the customers rate an organization’s products or services against competitors’ products or services. Also, Technical requirements that are not known to customers are identified and documented. These requirements generally stem from management or regulatory standards that a product must meet.
Relationship matrix defines the relationship between customer requirements and an organization’s ability to meet those requirements is determined. The relationship between the two factors is classified as weak, moderate, or strong and given the values of 1, 3, and 9, respectively. Even, in Importance weighting rating, Customer requirements are weighted according to their importance for defining and prioritizing key criteria. The relative importance of customer needs and the company’s and competitor’s performance are taken into account while calculating this. Target values for each product or service attributes, known as technical descriptors, that can be used as benchmarks against competitors’ target values are established. These target values are the “how much” of these product or service attributes.
The technical descriptors are compared with the competitors’ technical descriptors using scientific analytical techniques to assess their properties is called Engineering analysis. This also includes reverse engineering competitors’ products or services to determine the values for their technical descriptors. Correlation matrix is the relationship among customer requirements are analyzed to identify correlated requirements. The relationships are then ranked for determining areas of improvement that need to be focused upon.
Another roadmap of DFSS is DMADV, an acronym for five interconnected phases, namely Define, Measure, Analyze, Design, and Verify. This methodology is used in projects that involve creating a new product or process design.
Define – The project goals are defined so that they are in line with customer requirements and enterprise strategies.
Design – The details of the process are designed and optimized to meet the needs of customers followed by the performance of the new design which is tested through pilot runs before implementation.
Verify – In this phase the results are test and implementation of new design is carried out for large scale deployment.
This is the second article in the series that will help understand ‘What is Six in Six Sigma?‘ If you haven’t already read our article ‘What is Sigma in Six Sigma‘, we would like to recommend that you first do so.
For now, let’s look into what is Six in Six Sigma.
Let’s get started by understanding Customer Requirement and Actual Performance.
We are going to use the example of newspaper delivery everyday to your house. As a customer, you want newspapers to be delivered between 7:00 and 7:30 am (say within a half hour window). However, in reality, the paper gets delivered only between 6:00 to 9:00 am (a 3 hour window). So, in this case, the customer requirement or allowable variation is ’30 mins’ while the Actual Performance or Actual Variation is 3 hours.
On the contrary, your friend isn’t so particular about his newspaper delivery. He is in fact fine if they are delivered between 6:00 to 9:00 am (a 3 hour window). But in reality, his papers get delivered between 7:00 to 7:30 am (a half hour window).
How would you characterize these two situations?
Now, let’s answer the question ‘What is Six in Six Sigma?’
Six refers to the Sigma Capability of any process. In this case, the newspaper delivery process. When it’s Six, it means that the Standard Deviation or Sigma is so small that 6 Standard Deviations or 6 Sigmas can be fitted on either side of the bell-shaped curve. Based on the principle of bell-shaped curve (normal curve), 6 Sigma equals only 3.4 defects per million opportunities. For the newspaper example, it means that if there are 1 million days of newspaper delivery, only on 3.4 days (i.e. 3 or 4 days) of the delivery will be beyond your requirement. So, it is very obvious that your newspaper delivery isn’t at the Six Sigma level, but your friend’s delivery could be. It depends on the value of Standard Deviation. We covered the computation of standard deviation in ‘What is Sigma in Six Sigma’.
Let’s say for your friend’s process, only 5 standard deviations or sigmas can be fitted on either side of the bell-shaped curve, then, his sigma capability is at 5 or his newspaper delivery process is at 5 Sigma.
To sum up, if you want a particular process to be at Six Sigma, then you will have to manage the following:
Understand what the customer requirement is? If there is a window within which the customer wants her delivery or quality, then that becomes your customer requirement.