Identify the sampling technique used, and discuss potential sources of bias (if any). Explain.
A student asks 18 friends to participate in a psychology experiment.

Verified step by step guidance

1. Identify the sampling technique: The student is selecting participants based on convenience, as they are asking their friends. This is an example of a convenience sampling technique.
2. Explain convenience sampling: Convenience sampling involves selecting individuals who are easiest to reach or readily available. It is not random and does not ensure that every individual in the population has an equal chance of being selected.
3. Discuss potential sources of bias: Since the sample consists only of the student’s friends, it is not representative of the broader population. This introduces selection bias, as the sample may share similar characteristics (e.g., age, interests, or social background) that do not reflect the diversity of the entire population.
4. Explain the impact of bias: The lack of representativeness can lead to results that are not generalizable to the entire population. For example, conclusions drawn from this experiment may only apply to the student’s social circle and not to other groups.
5. Suggest improvements: To reduce bias, the student could use a random sampling technique, such as simple random sampling, where participants are chosen randomly from the entire population of interest. This would increase the likelihood of obtaining a representative sample.

Key Concepts

Sampling Technique

Sampling technique refers to the method used to select individuals from a population to participate in a study. In this case, the student is using a non-probability sampling technique known as convenience sampling, as they are selecting friends who are readily available rather than randomly selecting from the entire population.

Bias in Sampling

Bias in sampling occurs when certain members of a population are systematically more likely to be selected than others, leading to results that may not be representative. In this scenario, the potential bias arises from the fact that the sample consists only of friends, which may not reflect the broader population's diversity in terms of demographics, opinions, or behaviors.

Generalizability

Generalizability refers to the extent to which findings from a sample can be applied to the larger population. Due to the convenience sampling method and potential biases, the results of the psychology experiment may lack generalizability, making it difficult to draw conclusions that apply to individuals outside of the student's friend group.