NCEA Level 3 Statistics Practice Questions - NCEA Level 3 Statistics (National Certificate Of Educational Achievement) Exam

Sampling error arises purely from random variation in selecting a subset of the population, whereas non-sampling error arises from study design flaws, non-response, or measurement bias. Sampling error can be completely eliminated by increasing sample size, whereas non-sampling error decreases as sample size increases. Non-sampling error is quantified by the margin of error formula (1/√n), whereas sampling error cannot be calculated mathematically. Sampling error occurs only in observational studies, whereas non-sampling error occurs only in experimental trials.