ASQ certification CQE Updated Exam

When subgroups are selected in a way that minimizes the opportunity for variation within a subgroup and maximizes the opportunity to detect variation between subgroups, this subgrouping is known as rational subgrouping. Rational subgrouping is a concept used in control charting to ensure that the data within each subgroup is homogeneous, making it easier to detect special causes of variation between subgroups.References:

Statistical Quality Control by Douglas C. Montgomery.

ASQ Certified Quality Engineer Handbook.

Design Failure Mode and Effects Analysis (DFMEA) is a systematic method for evaluating a design to identify potential failure modes, their causes, and effects, and to prioritize the actions to mitigate these failures.

Identify Personnel Responsible for Implementation:

While important for action plans, it is not the primary focus of DFMEA.

Predict Failure Frequencies:

DFMEA does consider failure frequencies, but the primary goal is to address and mitigate failures.

Minimize Measurement Variation:

This is more relevant to process control and not the primary focus of DFMEA.

Mitigate Failure Modes:

The main objective of DFMEA is to identify potential failure modes and implement actions to reduce or eliminate the risks associated with these failures.

This involves analyzing the design to foresee where it might fail and taking preventive measures to improve reliability and safety.

References: Quality engineering and risk management texts, specifically those discussing the principles and objectives of DFMEA.