HKSM
precision
In quality management, precision describes the degree of exactness or fineness in results or measurements.
Key Points
- Precision focuses on how exact and consistent results or measurements are.
- High precision does not guarantee accuracy; values can be exact yet off from the true or target value.
- Quality control tools (e.g., repeated measurements, control charts) help assess precision by showing low variation.
- Requirements may specify precision tolerances (e.g., record to 0.01 units) to guide verification and testing.
Example
During performance testing, five runs show response times of 2.01 s, 2.00 s, 2.02 s, 2.01 s, and 2.00 s. The results are tightly clustered, indicating high precision, even if the target SLA is 1.50 s (which would be an accuracy concern).
PMP Example Question
A QA analyst notes that a measurement device consistently reports values 10 mm above the specification, with almost no variation across repeated checks. What quality characteristic is demonstrated?
- Accuracy
- Precision
- Prevention cost
- Conformance
Correct Answer: B — Precision
Explanation: The readings are consistent and tightly grouped (high precision) but not close to the true or target value (low accuracy).
