Sampling Methods

When conducting research, psychologists cannot usually study everyone in the population of interest. Instead, they select a sample — a smaller group of people who are intended to be representative of the wider population. The method used to select this sample can significantly affect the quality and generalisability of the findings.

---

Key Terms

Term	Definition
Population	The entire group of people that the researcher is interested in (e.g. all GCSE students in the UK)
Sample	The smaller group of people selected from the population to take part in the study
Sampling	The process of selecting participants from the population
Generalisability	The extent to which findings from the sample can be applied to the wider population
Bias	A systematic distortion in the sample that means it does not represent the population accurately

---

Sampling Methods

1. Random Sampling

Every member of the target population has an equal chance of being selected.

How: Names are drawn from a hat, or a random number generator is used to select participants from a complete list of the population.