Measurements Gone Wrong: What Real Failures Teach Us About Measurement Risk Most measurement failures don’t start with a dramatic mistake. They start with something ordinary: a unit that isn’t clearly defined, a calibration performed under the wrong conditions, a process step skipped because “it’s always been fine,” or a requirement that no one can clearly […]
Measurement Risk in Business Decisions: The Likelihood and the Consequences of Measurement Risk I’ve worked on this topic for many years and continue to teach, refine, and learn. This article reflects that ongoing process and is intended to clarify what measurement risk is, how it shows up in practice, and why it matters. Measurement risk […]
Understanding Risk: Making Better Measurement Decisions Understanding Risk Intro: Why Measurements Aren’t Always Exact Every measurement we take comes with some level of doubt. This doubt is called measurement uncertainty. It’s the range within which the “true value” probably lies. When understanding risk, think of it like reading a ruler: if your eyes […]
Start With the End in Mind: Working Backwards to Size Your Measurement Equipment and Calibration Provider A practical, risk-informed method for selecting equipment, decision rules, and calibration providers Abstract Begin with the decision you must defend—product conformance with acceptable risk—and work backwards to derive the measurement capability required of both your equipment and your […]
How to Calculate Load Cell Specific Risk Step-by-Step Instructions Many people struggle with decision rules and how to calculate risk. This article provides step-by-step instructions to calculate Measurement Uncertainty, Guard Band Acceptance Limits, and Probability of False Acceptance (PFA). Load Cell Specific Risk Example Calculation: To Calculate PFA, the Excel function is NORM.DIST. Risk upper […]
Guarded rejection: 1 Valuable Tool for Reducing the Risk of False Rejection When assessing the conformity of a product or service to a specified requirement, it is crucial to have a high degree of confidence in the decision. This is especially true when the consequences of a false rejection or false acceptance are high. Guarded […]
A Simplified Global and Specific Risk Example A company has hired us to measure the speed of cars on a stretch of a single-lane road. The customer wants options using both Global and Specific Risk examples as they are unsure what method will give them what they need to meet the specification as they know […]
Understanding Global Risk in Simple Terms In the world of engineering and product design, there's a concept that Henry Petroski discusses in his book, "To Engineer is Human: The Role of Failure in Successful Design." He suggests that engineers and companies might become complacent when things are going well. They might not take the necessary […]
Delving into Specific Risk: A Comprehensive Understanding of PFA and PFR Specific risk in metrology, mainly focusing on the Probability of False Acceptance (PFA) and Probability of False Rejection (PFR). These concepts are crucial in the decision-making process based on measurement results. Specific Risk Specific risk, as the term suggests, is a risk that is […]
A Simplification of the Differences Between Specific and Global Risk Understanding the Differences Between Specific and Global Risk is a complex topic. For this article, we are going to explain the difference between specific and global risk without getting into too much detail. In metrology, risk is a crucial factor influencing the decision-making process based […]
Decision Rules - Our Top 10 Recommended Reading Many people struggle with decision rules and implementing decision rules. At Morehouse, we have been privileged to be part of the Metrology Handbook 3rd Edition, where we helped write a chapter on decision rules. Though it was an honor to write that and other chapters, there are […]
What can happen when we use an accuracy specification and assume all the measurements are centered in relation to the specification limits? It is a typical problem in the metrology community, where many papers assume a centered process or Measurement. When the Measurement deviates from the true value, it is said to have a bias […]
