ACCA Audit and Assurance (F8) Practice Exam

Which sampling method involves selecting every nth item from a population?

1. Haphazard sampling

2. Random sampling

3. Systematic sampling

4. Block sampling

The correct answer is: Systematic sampling

Systematic sampling is a method that involves selecting every nth item from a population after an initial random start. This approach allows for a simple and straightforward way to obtain a sample that is spread throughout the entire population without the bias that might occur in other sampling techniques. For instance, if a researcher decides to sample every 10th item from a list of 1000 items, they would first randomly select a starting point (say the 3rd item) and then every 10th item from that point onward (3rd, 13th, 23rd, etc.), allowing them to achieve a representative sample with ease. This method is particularly useful when the population is homogeneous because it ensures that the sample is evenly distributed and helps improve efficiency when collecting data. In contrast, haphazard sampling may lack a systematic approach, random sampling doesn't follow a fixed pattern, while block sampling typically involves selecting groups or clusters rather than individual items in a systematic manner. Each of these methods serves different purposes and has its own applications, but for the specific scenario described in the question, systematic sampling is the most appropriate choice.