A university has 1875 first-year students arranged alphabetically in a database. A researcher requires a systematic sample of 125 students. The random starting position is 9.
Calculate the sampling interval and write down the last three positions selected.
State one reason why an alphabetical ordering is unlikely to create periodic bias in this investigation.
Explain why a random starting position is still required.
36 exam-style questions on WJEC A Level Maths 2.1 Statistical Sampling, covering 2.1.1 Statistical Sampling, 2.1.2 Statistical Sampling, 2.1.3 Statistical Sampling, 2.1.4 Statistical Sampling, and 2.1 Statistical Sampling. Each one has a worked solution and a mark scheme showing where the marks go.