Random Sampling

What is random sampling?

• Choosing a sample based on personal preference.

• Selecting a sample where each member of the population has an equal chance of being chosen.

• Sampling only friends and family.

• Sampling based on specific traits like age or income.

Why is random sampling important in research?

• It helps to save time and money.

• It ensures the sample is biased towards a specific group.

• It provides a fair representation of the entire population.

• It only selects the people who are available.

Which of the following is NOT a method of random sampling?

• Lottery method

• Using a random number table

• Choosing whoever is closest to the door

• Drawing names from a hat

In a school, a teacher wants to select 5 students randomly from a class of 30 for a survey. Which method could be considered random sampling?

• Selecting the first five students who arrive in class.

• Asking students to volunteer and choosing the first five who do.

• Writing each student's name on a piece of paper, mixing them in a bowl, and drawing five names.

• Choosing the five tallest students.

What is a key characteristic of a random sample?

• It is the easiest sample to obtain.

• It includes members from one part of the population.

• Every member of the population has a known and equal chance of being included.

• It focuses on a specific demographic.

Elise, a supermarket employee, approached 50 random customers and asked whether they would be willing to discuss what they like most about the store. She interviewed the 22 who said yes. Is this sample of the supermarket's customers likely to be biased?

• yes

• no

Leslie wants to find out what show students watch the most.  She surveyed the 9 youngest students in the elementary school.  Is this sample of the students in the school likely to be representative?

• yes
• no
• Mr. Shinn, I have no idea!

A teacher wants to know the average time spent doing homework by the students in her class of 20 girls and 5 boys.
She picks the student in every 5th seat.

• Simple Random
• Systematic Random
• voluntary response
• convenience

Mr. Thrasher wants to know how the students at Cedar Bluff rate the cafeteria. He surveyed the hungry baseball team after practice last week to rate the school cafeteria. Is this a biased sample of the school's population?

• Yes, because it only asked one group of students

• No, the baseball team has the smartest students

• Yes, because it's voluntary survey

• No, the baseball team are good food critics

Karla is doing a study to see what the town thinks of the new grocery store. She chooses a convenience sample. She

asks 13 people from the town who go to the new grocery store. Is there bias in her sample?

• Yes

• No