Question

What are the three stages of dividing a sampling frame into distinct groups, taking an SRS within each strata, and combining data using population percentages as weights to get total population results?

1) Stage 1: divide sampling frame into distinct groups, Stage 2: take an SRS within each strata, Stage 3: combine data using population percentages as weights to get total population results
2) Stage 1: take an SRS within each strata, Stage 2: divide sampling frame into distinct groups, Stage 3: combine data using population percentages as weights to get total population results
3) Stage 1: combine data using population percentages as weights to get total population results, Stage 2: divide sampling frame into distinct groups, Stage 3: take an SRS within each strata
4) Stage 1: divide sampling frame into distinct groups, Stage 2: combine data using population percentages as weights to get total population results, Stage 3: take an SRS within each strata

Answer 1

The three stages of stratified sampling are dividing the population into strata, taking a simple random sample within each stratum, and combining the samples with population weights.

Step-by-step explanation:

When sampling a large population, a common method employed by statisticians is the stratified sampling technique. This method involves dividing the population into subgroups or strata, then taking a proportionate simple random sample (SRS) from each stratum, and finally combining these samples to make a single sample that represents the entire population. The process of stratified sampling unfolds as follows:

1. Stage 1: Divide the sampling frame into distinct groups (strata) based on shared characteristics. This helps to ensure that all subgroups of the population are represented adequately in the sample.
2. Stage 2: Within each stratum, take an SRS. To do this, number each member within the stratum and use a random process to select members such that the number of individuals selected from each stratum is proportionate to its size in the population.
3. Stage 3: Combine data using population percentages as weights to obtain results that reflect the total population. This involves adding together the results from each stratum in a way that each stratum's influence on the final result corresponds to its proportion in the entire population.

Based on the explanation above, the correct sequence of stages for stratified sampling is Option 1:

• Stage 1: Divide sampling frame into distinct groups,
• Stage 2: Take an SRS within each strata,
• Stage 3: Combine data using population percentages as weights to get total population results.