Systematic
or Determinate Errors: Shifts in the
measured values from the true values which reduces the accuracy of a result. They
have a definite source that usually can be identified by the observer. They can often be eliminated by simply
changing the experimental procedure.
(An example of a systematic error is misreading a buret).
Random
or Indeterminate Errors: Shifts in the measured values from the
true values which influences the precision or scatter of the
result. They have an indeterminate
source and are usually not by the observer.
(Examples
of random errors might be the imprecision among multiple readings; or an
unnoticed change in temperature, pressure, or humidity; or a fluctuation in
voltage during a measurement).