🏘️ What is Cluster Sampling?

🏘️ What is Cluster Sampling?

Answer: In Cluster Sampling, the population is divided into natural groups (clusters) such as villages, schools, or wards. A few clusters are randomly selected, and all or some units within selected clusters are studied.

Advantages:

• Economical and operationally feasible for large areas.

• Reduces cost of travel and listing.

Disadvantages:

• Less precise due to homogeneity within clusters (high intra-class correlation).

• Requires adjustment for cluster effect.

Follow-up: 👉 When is it more efficient than SRS?

→ When cost of complete listing is very high and clusters are internally heterogeneous but similar in composition.

ISS Example: In NSS surveys, villages (rural) or urban blocks (urban) are treated as clusters (First-Stage Units).