What is the difference between accuracy and precision?

What is the difference between accuracy and precision?

• A. Precision describes how close a measurement is to the true value.
• B. Accuracy describes how close a measurement is to the true value, while precision describes how consistent repeated measurements are.
• C. Accuracy describes the consistency of repeated measurements.
• D. Precision describes how consistent repeated measurements are.

Answer: (C)

Accuracy vs precision: accuracy is how close your measurement is to the true value, while precision is how consistently you can repeat measurements. The best statement captures both ideas: accuracy describes closeness to the true value, and precision describes how repeatable the measurements are. Think of a target with darts: if the darts land near the bullseye, you’re accurate; if they land in the same spot shot after shot, you’re precise. You can have one without the other: you might hit near the bullseye every time (accurate but not precise if the hits are spread), or cluster tightly in a corner away from the bullseye (precise but not accurate). The other options mix up which term describes closeness to the true value and which describes repeatability.

Accuracy vs precision: accuracy is how close your measurement is to the true value, while precision is how consistently you can repeat measurements. The best statement captures both ideas: accuracy describes closeness to the true value, and precision describes how repeatable the measurements are.

Think of a target with darts: if the darts land near the bullseye, you’re accurate; if they land in the same spot shot after shot, you’re precise. You can have one without the other: you might hit near the bullseye every time (accurate but not precise if the hits are spread), or cluster tightly in a corner away from the bullseye (precise but not accurate). The other options mix up which term describes closeness to the true value and which describes repeatability.