Non-sampling error is the error that results from under-coverage, non-response bias, response bias, or data-entry errors. Sampling error is the error that results because a sample is being used to estimate information about a population.
Explanation:
Sampling error is related to the variation between the true values of the sample and the population. If occurred, it is always random depending upon the sample chosen.
Non-sampling error can be random as well as non-random. Non-sampling error can occur irrespective of the sample chosen. It is related to the inappropriate analysis of the data.
