Random error

In engineering and physics, random error or accidental error is an unavoidable error that is produced by unique events that cannot be controlled during the measurement process. It is opposed to the concept of systematic error.

In a research study, random or accidental error is determined by taking only a sample from a population to make inferences. It can be decreased by increasing the number and size of the sample. Quantification:

1. Proof of hypothesis
2. confidence interval

The sources of random errors are difficult to identify or their effects cannot be fully corrected. They are numerous and small, but their accumulation causes the measurements to fluctuate around an average.