Question

You, as a researcher, were asked to investigate differences in fruit and vegetable consumption among males and females in your city. Suggest three different probabilistic sampling methods to design this study. The sampling frame must be also stated. Explain your answers.

Answer 1

Here we are asked to investigate differences in fruit and vegetable consumption among males and females in your city. Suggest three different probabilistic sampling methods to design this study. The sampling frame must be also stated.

1) We can use stratified sampling to investigate the above scenario.

Let us consider a population having N population units. We divide this population into 2 stratum according to gender namely male and female where the ith strata contains Ni population units. Now from each strata a random sample is drawn by simple random sampling with replacement or simple random sampling without replacement. From these samples of size ni we check the fruit or vegetable consumption.

2) We can use cluster sampling to investigate the above scenario.

Let us consider the population is divided into 2 clusters on basis of the gender of size M. From these 2 clusters n clusters are drawn by simple random sampling with replacement or simple random sampling without replacement. Now the drawn clusters are completely enumerated to check the consumption of fruit or vegetables.

Total population size= 2M

Total sample size= nM

3) We can use multistage sampling to investigate the above scenario.

In stage 1 we choose 2 clusters from the population according to the gender. Then in stage 2 we use simple ramdom sampling to select a subset of elements from each cluster for the final sample. Now from these final sample we check for consumption of fruit or vegetables.