Sampling Methods: Probability vs. Non-Probability

The question asks to identify the sampling method that does not belong to the "probability" category. Probability sampling methods ensure that every individual in the population has a known, non-zero chance of being selected for the sample. This randomness is key.

Probability Sampling Methods

The following are considered probability sampling methods:

• Systematic sampling: Involves selecting elements from a list at regular intervals (e.g., every 10th person). Each element has a predetermined probability of selection.
• Stratified sampling: The population is divided into subgroups (strata), and random samples are drawn from each stratum. This ensures representation from all groups.
• Cluster sampling: The population is divided into clusters (groups), some clusters are randomly selected, and then all individuals within the selected clusters are sampled.

Non-Probability Sampling Method

Quota sampling is different. In this method, researchers set specific quotas for different subgroups based on certain characteristics (like age, gender, or occupation). However, the selection of individuals within these quotas is non-random and often left to the interviewer's convenience. Because the selection isn't based on chance, it's not a probability method.

Conclusion

Since every member of the population does not have a known, equal, or predetermined chance of being selected in quota sampling, it is not a probability method.

Therefore, the correct answer is Quota sampling.