Sampling Techniques: Methods for Choosing a Representative Sample

The video tutorial explores various sampling techniques, including random, systematic, stratified, quota, and opportunity sampling. It discusses the importance of selecting a representative sample and the challenges associated with each method. The tutorial also examines the application of these techniques in political polling, highlighting the complexities and potential errors in predicting election outcomes.

Why is it important for a sample to be representative of the overall population?

• To ensure the sample is large enough

• To accurately infer information about the population

• To make data collection easier

• To reduce the cost of sampling

What is a major challenge of true random sampling?

• Assigning numbers to a large population

• It always results in a biased sample

• It is easy to implement

• It requires a small population

What is a potential issue with systematic sampling?

• It is too random

• It can miss systematic patterns in the data

• It is too expensive

• It requires a large sample size

In stratified sampling, how are subgroups represented?

• Equally, regardless of size

• Proportionately, based on their size in the population

• Only the largest subgroups are included

• Randomly, without any specific rule

What distinguishes quota sampling from stratified sampling?

• Quota sampling is more accurate than stratified sampling

• Quota sampling uses random selection within subgroups

• Quota sampling does not ensure proportional representation

• Quota sampling does not use random selection within subgroups

What is a key characteristic of opportunity sampling?

• It is the most accurate sampling method

• It is always representative of the population

• It requires a large sample size

• It is based on convenience and availability

Why are university students often used in opportunity sampling?

• They are the most diverse group

• They provide the most accurate data

• They are the only available participants

• They are easily accessible and willing to participate

What is a common method used by polling companies to gather samples?

• Stratified sampling

• Systematic sampling

• Random sampling

• Opportunity sampling

What is a margin of error in political polling?

• The cost of conducting the poll

• The number of people who refused to participate

• A range indicating potential variation in poll results

• The exact percentage of error in the poll

What challenge do polling companies face with non-respondents?

• They are easy to replace

• They provide the most accurate data

• They always vote the same way

• Their absence may skew the sample