Question

A public library wants to determine the research needs of children and adults who access the reference section. You will use stratified sampling.

1. Define the population.

2. Define the sample frame.

3. Explain how you would select the sample.

4. Explain how you would gather the data.

Answer 1

1. Population:- all children and adults who access the reference section

2. Sampling Frame- A sampling frame is a list of the items of the population from which a sample is to be obtained.

So here  list of people who visits the library become the sampling frame.

This list may contain senior citizens and youth also. These are not eligible items for being members of the population. They need to removed before a sample is made.

The sampling frame may not contain all the children and adults who access reference section as this lists contains only those people who visits library. In that case, some eligible items of the population are left out from sampling.

3.Seven steps to create stratified sample are:-

(a) defining the population;

(b) choosing the relevant stratification;

(c) listing the population;

(d) listing the population according to the chosen stratification;

(e) choosing your sample size;

(f) calculating a proportionate stratification;

(g) using a simple random or systematic sample to select your sample.

So here sample can be selected randomly from the list or sample can be selected in a systematic way such as every 3rd person(say) from the list can be questioned.

4. data can be gathered in following ways:-

• Direct Observation
• Experiments,
• Surveys.