Question

What is a real life example of stratisfied sampling that has a bias of non-response and measurment ?

Answer 1

STRATIFIED SAMPLING::-

Stratified sampling refers to a type of sampling method . With stratified sampling, the researcher divides the population into separate groups, called strata. Then, a probability sample (often a simple random sample ) is drawn from each group.

Stratified testing has a few favorable circumstances over straightforward arbitrary examining. For instance, utilizing stratified inspecting, it might be conceivable to decrease the example measure required to accomplish a given exactness. Or on the other hand it might be conceivable to build the exactness with a similar example estimate.

EXAMPLE OF STRATIFIED SAMPLING::-

Assume an exploration group needs to decide the GPA of understudies over the U.S. The exploration group experiences issues gathering information from every one of the 21 million undergrads; it chooses to take an arbitrary example of the populace by utilizing 4,000 understudies.

Presently expect that the group takes a gander at the distinctive qualities of the example members and miracles if there are any distinctions in GPAs and understudies' majors. Assume it finds that 560 understudies are English majors, 1,135 are science majors, 800 are software engineering majors, 1,090 are building majors, and 415 are math majors. The group needs to utilize a relative stratified irregular example where the stratum of the example is corresponding to the arbitrary example in the populace.

Assume the team researches the demographics of college students in the U.S and finds the percentage of what students major in 12% major in English, 28% major in science, 24% major in computer science, 21% major in engineering, and 15% major in mathematics. Thus, five strata are created from the stratified random sampling process.
The group then needs to affirm that the stratum of the populace is in extent to the stratum in the example; be that as it may, they discover the extents are not equivalent. The group then needs to resample 4,000 understudies from the populace and haphazardly select 480 English, 1,120 science, 960 software engineering, 840 building, and 600 arithmetic understudies. With those, it has a proportionate stratified arbitrary example of understudies, which gives a superior portrayal of understudies' school studies the U.S. The specialists would then be able to feature particular stratum, watch the changing investigations of U.S. understudies and watch the different review point midpoints.