13-multistage

# 13-multistage - Multistage Sampling Example Multistage...

This preview shows pages 1–3. Sign up to view the full content.

1 Multistage Sampling Example Suppose eligible respondents (age 15+) are grouped according to their residential addresses (clusters). A sampling frame of the addresses is available. Simple random sample of addresses is selected from the frame. Multistage Sampling Example (cont) y If every eligible respondent in the selected address is asked to provide individual information, then we have cluster sampling. y However, in most of the cases only one randomly selected individual from the selected address will provide individual information. Then, we have two stage sampling. Multistage Sampling Example (cont) Suppose 1000 addresses are selected. Since only one member from each address is being interviewed, there are 1000 respondents as well. Suppose out of these 1000 respondents, 800 are Chinese. Is 800/1000 = 0.8 an estimate of the proportion of Chinese in the target population? Ans: No, but why? Multistage Sampling Two-stage Cluster Sampling A two-stage cluster sampling is obtained by first selecting a simple random sample of cluster (primary sampling unit, psu) and then selecting a simple random sample of element (secondary sampling units, ssu) from each sampled cluster. Multistage Sampling Two-stage cluster sampling Notations: For the population: M : Number of cluster (psu) in the population N : Number of elements (ssu) in the i th cluster i N : Number of elements in the population : Average cluster size of the population Y ij : Measurement of the j th element in the i th cluster T i : The i th cluster total : The i th cluster mean N i Y Multistage Sampling Two-stage Cluster Sampling Notations T : Population total : Population mean : Average per cluster Y Y c

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document