Estimation of measurement uncertainty in chemical analysis

Self-test 2

It has been explained in this section that there are effects contributing to measurement uncertainty – uncertainty sources – and that these effects can be either random or systematic by their nature. The following test enables you to test whether you understand what an uncertainty source is and what are the main properties of random and systematic effects.

Which of the following statements about measurement uncertainty, random effects and systematic effects are correct?

Correctly estimated measurement uncertainty takes into account both random and systematic effects.

It is often possible in practice to eliminate all uncertainty sources so that measurement results will have no uncertainty.

Random effects can never be entirely eliminated but their influence on the result can be decreased by making multiple repeated measurements.

Uncertainty sources are the cause of deviation of the measured value from the true value.

Systematic effects can in principle be corrected and thereby minimized or even eliminated.

Systematic effects can be minimized (or even eliminated) by performing the measurement in large number of repetitions.