Bias refers to

• A. The random error component in measurements
• B. The result of systematic errors
• C. The instrument's precision
• D. The average of repeated measurements

Answer: (B)

Bias is the systematic deviation of a measured value from the true value, caused by errors that repeat in the same direction each time you measure. This means there’s a consistent offset due to calibration, method, or instrument response that makes readings tend to be too high or too low. It’s different from random error, which causes measurements to scatter and affects precision rather than accuracy. Because bias reflects a persistent effect, repeated measurements will, on average, sit offset from the true value, which is why correcting systematic errors is essential for accuracy. The average of repeated measurements can reveal bias if it stays biased relative to the true value, but bias itself is the underlying systematic error causing that offset.