A Level Biology Practice Exam

In which type of sampling is the sample deliberately chosen rather than selected at random?

1. Systematic sampling

2. Non-random sampling

3. Simple random sampling

4. Stratified sampling

The correct answer is: Non-random sampling

The correct answer highlights that in non-random sampling, the selection of samples is intentional rather than based on chance. This method is useful when researchers aim to target specific characteristics within a population or when certain subgroups are of particular interest. For instance, researchers might want to study a rare disease and therefore intentionally choose individuals with that condition to obtain more relevant data. The other sampling methods, such as systematic, simple random, and stratified sampling, each involve random selection processes. In systematic sampling, the researcher selects every nth individual from a list, while simple random sampling means every individual in the population has an equal chance of being chosen. Stratified sampling involves dividing the population into distinct subgroups and then selecting random samples from each subgroup to ensure representation. Thus, these methods do not align with the concept of deliberately choosing samples.