Experimental error

Experimental error
See also

Experimental error is the difference between the values we receive when conducting the experiment. It is impossible to analyze the results of the experiment if we do not have certain assumptions about the error of the experiment, it is very important[1]. According to D.H. Stamatis: „Therefore, when we do an experiment, we assume that the response measure Y, is a function of a) parameters related to the experimental design and b) experimental error”[2]. An experiment using a smaller experimental error is usually stronger than an experiment using a more experimental error[3]. Sources of experimental error[4]:

  • sampling
  • assignment
  • conditions
  • measurement

Types of experimental errors

Experimental errors are divided into constant or systematic error and random error. The basis of experimental reasoning is understanding this type of error and learning how to deal with it[5].

Systematic or constant error it is characterized by the fact that the experimental conditions are the same each time the experiment is repeated. Constant error is e.g. an error resulting from the time of day. The effect of this error is masking by distorting the results[6].

A random error favoring one experimental condition or sometimes an accident is called a random error. If the error has constant and random components then it is an error from any source. The effect of this error is obscuring the results, it does not distort them in any[7].

Conduct in case of experimental error

Experimental error affects the experiment, so it should be repeated to draw the appropriate conclusions. Replication is any full repetition of an experiment. The best procedure is to estimate the possible experimental error before the experiment based on your previous experience. Then determine the number of repetitions and perform all parts of the experiment in random order. In order for the conclusions to be more reliable, the experimental technique should be improved[8]. Stamatis D.H. wrote: „Because a few replications of a refined technique can achieve the same reliability as many replications of a coarse technique, the choice of method in particular investigation may be made on the basis of cost[9].



  1. Stamatis D.H.(2002)
  2. Stamatis D.H.(2002)
  3. Stamatis D.H.(2002)
  4. Burns R.B.(2012)
  5. Burns R.B.(2012)
  6. Burns R.B.(2012)
  7. Burns R.B.(2012)
  8. Stamatis D.H.(2002)
  9. Stamatis D.H.(2002)

Author: Oliwia Kamińska