Rating & Aggregation Rule
My this article is intended to Assessor community & NOT to Process Improvement practitioners. Rating Rule: Existing rule: ISO/IEC 15504 Part 2 requires to rate Process Attribute (PA). In Practice: In most of the assessments, BPs & sometimes GPs are also rated. These ratings have been used to derive Process Attribute rating. Solution: ISO/IEC 33020 (which replaces ISO/IEC 15504 Part 2) now defines three types of rating, R1, R2 & R3. The meaning of these ratings is: R1: a) Characterize process outcomes, i.e., Characterize BP for each process instance b) Characterize process attribute outcomes, i.e., Characterize GP for each process instance c) Aggregate BP characterization of all process instances to PA1.1 rating d) Aggregate GP characterization of all process instances to respective PA rating R2: a) Characterize process attribute for each process instance b) Aggregate process attribute characterization of all instances to PA rating