I am currently taking a research methods course online. Today we talked about systematic and random error. The instructor pointed out that systematic error is expected to influence the mean of an estimate, while random error is expected to influence the variance of an estimate, but not the mean.
My observation is that there is a relationship between the sources of error and the effect on the distribution of my estimate:
- Systematic error affects the 1st moment (the mean)
- Random error affects the 2nd moment (variance)
Are there other forms of error which can alter other moments, like skew?