Distinguish Accuracy from Precision

Front

What is the definition of accuracy in measurements?

Back

Accuracy refers to how close a measured value is to the actual (true) value.

Front

What is the definition of precision in measurements?

Back

Precision refers to how close the measured values are to each other, regardless of whether they are close to the actual value.

Front

What does it mean if a set of data is both accurate and precise?

Back

It means the data points are close to each other and also close to the actual value.

Front

What does it mean if a set of data is precise but not accurate?

Back

It means the data points are close to each other but far from the actual value.

Front

What does it mean if a set of data is accurate but not precise?

Back

It means the data points are close to the actual value but not close to each other.

Front

What does it mean if a set of data is neither accurate nor precise?

Back

It means the data points are neither close to each other nor close to the actual value.

Front

Give an example of high accuracy and high precision.

Back

All measurements are very close to the true value and to each other, e.g., measuring a length of 10.00 cm multiple times and getting 10.01 cm, 10.00 cm, and 9.99 cm.

Front

Give an example of high precision but low accuracy.

Back

All measurements are close to each other but far from the true value, e.g., measuring a length of 10.00 cm multiple times and getting 8.00 cm, 8.01 cm, and 8.02 cm.

Front

Give an example of high accuracy but low precision.

Back

Measurements are close to the true value but vary widely, e.g., measuring a length of 10.00 cm and getting 9.90 cm, 10.10 cm, and 9.95 cm.

Front

What is the bullseye analogy in accuracy and precision?

Back

In the bullseye analogy, hitting the center represents high accuracy, while hitting the same spot repeatedly represents high precision.