Sampling Methods and Stratified Sampling

The video tutorial discusses different types of sampling, focusing on random sampling and its limitations in achieving equal representation. It highlights the probability of unequal representation in random samples and introduces stratified random sampling as a solution. The concept of strata is explained, emphasizing the importance of proportional representation of subgroups within a sample.

What is a key limitation of random sampling?

• It can sometimes fail to achieve its intended goal.

• It is the most expensive sampling method.

• It is the only method used in research.

• It always provides equal representation.

Why is the number nine significant in the context of sampling?

• It is the number of days in a week.

• It is the average number of samples needed.

• It represents the number of justices in the U.S. Supreme Court.

• It is the number of students in a classroom.

What is the purpose of assigning numbers to students in a sampling process?

• To facilitate random selection.

• To track their attendance.

• To identify their academic performance.

• To determine their age group.

What is the probability of having a more than two-to-one majority in a random sample of nine students?

• 100%

• 75%

• 51%

• 25%

What does a 51% probability indicate in the context of random sampling?

• The sampling method is flawed.

• Equal representation is guaranteed.

• There is a high chance of unequal representation.

• The sample size is too small.

What is the main goal of stratified random sampling?

• To simplify the sampling process.

• To reduce the cost of sampling.

• To ensure equal representation of subgroups.

• To increase the sample size.

In stratified sampling, what are the subgroups called?

• Layers

• Strata

• Segments

• Divisions

Why is it important to consider subgroups in a target population?

• To increase the sample size.

• To simplify data analysis.

• To reduce the number of samples needed.

• To ensure the sample is diverse.

How can stratified sampling be applied in a school setting?

• By selecting students randomly without any criteria.

• By ensuring the sample reflects the gender distribution of the school.

• By selecting students based on their age.

• By choosing only the top-performing students.

What is a potential issue with using an odd number for stratified sampling?

• It reduces the accuracy of results.

• It may not perfectly reflect subgroup proportions.

• It increases the cost of sampling.

• It complicates the sampling process.