Discover the Causes, How to Identify and Correct Them
Systematic errors are an inevitable reality when it comes to measurements, but what makes them so critical? It’s not just about small discrepancies: a systematic error is a constant deviation between the measured value and the true value. If overlooked, it can have significant consequences, such as altering product quality and compromising delicate industrial processes. Understanding what it is and how to address it is the first step toward ensuring accurate and reliable results.
How to identify a systematic error?
Have you ever noticed that measurements with the same instrument consistently differ from a reference value? This might indicate the presence of a systematic error. To detect it, performing repeated measurements in controlled conditions and comparing them to a certified standard is crucial. If the measurements consistently deviate, a systematic error is likely present. Using GUM (Guide to the Expression of Uncertainty in Measurement) procedures during calibration can improve the ability to identify these deviations, ensuring data complies with accuracy standards.
Systematic error vs random error: what’s the difference?
Systematic and random errors might seem similar, but they have different causes. Systematic error is predictable and constant, always affecting measurements in the same direction. Random error, on the other hand, is unpredictable and varies from one measurement to another, often due to factors like environmental fluctuations or mechanical wear of the instruments. To mitigate systematic error, proper calibration is needed, whereas for random error, improving measurement techniques and controlling external variables is essential.
Main causes of systematic errors
Systematic errors often stem from incorrect calibration of instruments. If an instrument is not properly calibrated against a recognized standard, all measurements will be skewed. Even constant environmental conditions, such as temperature or humidity, can systematically affect results. Operational errors or improper measurement techniques also contribute. Regularly monitoring instruments and adjusting them to operational conditions is crucial for reducing the risk of systematic errors.
Correcting a systematic error
Once identified, it’s essential to address the systematic error to ensure measurement accuracy. The first step is adjusting or calibrating instruments according to GUM standards. If the working environment is a determining factor, controlling and adjusting environmental conditions can help reduce the error. Additionally, advanced statistical techniques, such as comparing with traceable reference data, can assist in proactively detecting and correcting the error.
Systematic errors and product quality
Imagine a pharmaceutical company producing liquid medicines. If a scale used to weigh key ingredients has a systematic error, the amount of active ingredient measured could be consistently incorrect, compromising the drug’s effectiveness and potentially patient health. In such a sensitive industry, the reliability of measurements is crucial, and a systematic error can have severe consequences, both in terms of quality and safety.