Which of the following statements are false about accuracy and precision: Select one: Accuracy defines the exactness of a measure to its true value; b
The Correct Answer and Explanation is:
Correct Answer: The statement is FALSE.
✅ Corrected Statement:
Accuracy defines how close a measured value is to the true or accepted value, not its “exactness.”
🧠 Explanation
Understanding the concepts of accuracy and precision is fundamental in fields like science, engineering, and statistics. While often used interchangeably in everyday language, they have distinct meanings in technical contexts.
Accuracy refers to the closeness of a measured value to the true or accepted value. It tells you whether your measurement hits the correct or “target” value. For example, if a thermometer reads 100.0°C when the actual boiling point of water is 100.0°C, the measurement is accurate.
However, the statement “Accuracy defines the exactness of a measure to its true value” is misleading and false, because exactness is more closely related to precision, not accuracy.
Precision, on the other hand, describes the repeatability or consistency of measurements. If you take several measurements and get very similar results each time (e.g., 99.8°C, 99.9°C, 99.8°C), those results are precise—even if they are not close to the true value (100.0°C). Precision does not require correctness, only consistency.
Here’s a helpful analogy using target shooting:
- High accuracy, high precision: Shots are close together and centered on the bullseye.
- High precision, low accuracy: Shots are close together but far from the bullseye.
- High accuracy, low precision: Shots are spread out but average around the bullseye.
- Low accuracy, low precision: Shots are scattered and far from the bullseye.
In conclusion, accuracy deals with correctness, while precision deals with consistency. Saying that accuracy defines exactness incorrectly merges the two concepts, making the statement false. Proper understanding of this distinction is crucial when analyzing or improving measurement systems.
