Systematic Error
A consistent, repeatable error in experimental measurements that skews data in the same direction from the true value.
Governing formula
Offset = Mean Measured - True Value
SI unit
Various
In depth
Systematic errors arise from faulty instrument calibration, zero errors, environmental bias, or flawed experimental technique. Unlike random errors, systematic errors cannot be eliminated by averaging repeated trials; they require re-calibration or theoretical corrections.
Examples in the real world
A bathroom scale that reads 1.5 kg when empty, or an uncalibrated thermometer that consistently reads 2°C too high.