Affinity diagram in six sigma diagram. This is one of the top business frameworks helping clients improve on their approach to strategy, project management, IT, HR, internal processes and client experience.Affinity diagram in six sigmaA six sigma diagram is a graphical format of the six sigma concept of quality management. It is used to represent the relationship between the level of a quality attribute and the probability of occurrence, expressed as a scale from one end of the line to the other. It is commonly used in the context of lean manufacturing and continuous improvement. It was developed in the 1980s by the Japanese company Toyota and based on a diagram developed by the Swedish scientist Johan Sundberg.