Random Sampling Methods and Issues

The video tutorial by Maria Miller from MathMoth.com covers the concept of random sampling, a method used when studying an entire population is impractical. It explains the requirements for a sample to be considered random, including randomness and external selection. The tutorial uses the 2008 presidential campaign polls as a case study to illustrate the importance of method over sample size. It also discusses various methods for obtaining random samples, highlighting the pros and cons of each. The lesson concludes with a summary of the key points discussed.

What is the primary reason for using sampling in research?

• To avoid bias

• To include every individual

• To ensure accuracy

• To save time and resources

Why can't researchers study the entire population?

• It's unethical

• It's unnecessary

• It's impractical due to size

• It's too expensive

What is a key requirement for a sample to be considered random?

• It must be large

• It must be diverse

• Each member must have an equal chance of selection

• It must be convenient

What is meant by 'external selection' in random sampling?

• Participants choose themselves

• Participants are selected by a computer

• Researchers select participants

• Participants are selected by chance

In the 2008 presidential campaign example, why was the Gallup poll more accurate than the AOL poll?

• It had a larger sample size

• It used a random sampling method

• It was conducted online

• It was conducted after the election

What was a major flaw of the AOL poll?

• It was biased

• It was too small

• It was self-selected

• It was too expensive

Which method is most effective for obtaining a random sample in a store?

• Giving forms to exiting customers

• Standing in a specific aisle

• Calling randomly from a customer database

• Interviewing people at the entrance

Why is standing in a specific aisle not a good method for random sampling?

• It excludes certain shoppers

• It is too time-consuming

• It is too expensive

• It is too random

What is a drawback of giving forms to customers to fill out later?

• It is too costly

• It leads to self-selection

• It is too slow

• It is too random

What is a potential issue with using a store's customer database for random sampling?

• It is too time-consuming

• It is too random

• It is too expensive

• Not all customers are in the database