Samples & Populations

Samples vs. Populations

By Ashley Carson

​Population

​The entire group that is being surveyed.

​

Key words can include :

• ​all

• ​entire

• ​whole

​Sample

​Part of the population

​What is being surveyed

​

​Examples include :

• ​piece of a pie

• ​what you buy in a store

• ​sample from a bakery

Multiple Choice

Ms. Carson wants to know what the students at NMS's favorite ice-cream flavor is. She asks her students what their favorite flavor is. What is the population?

• Students at NMS

• Mrs. Carson's students

• All staff members at NMS

• All 7th grade students

Multiple Choice

Ms. Carson wants to know what the students at NMS's favorite ice-cream flavor is. She asks her students what their favorite flavor is. What is the sample?

• Students at NMS

• Mrs. Carson's students

• Staff members at NMS

• 7th grade students

​Random Sample

​This is the best way to have a representative sample.

​Random samples make sure every option has an equal chance of being chosen.

​

​Examples include :

• ​Patterns, every 3rd customer

• ​Drawing a name from a hat

• ​Blindly picking a marble from a bag

Multiple Choice

_______ is a part of a group being surveyed.

• Sample

• Population

• Random Sample

• Quartile

Multiple Choice

_______ is the entire group of objects or individuals considered for a survey.

• Sample

• Population

• Random Sample

• Quartile

Multiple Choice

A musician wanted to see what people who listened to his last album thought about the songs. Which choice is the best sample?

• Every person who listened to the album.

• A selection of people who didn't want to listen to the album

• 250 girls who listened to the album

• A selection of 3,294 people who listened to the album.

Multiple Choice

A beverage company wanted to see if people in the United States liked their new logo. Which choice best represents a population?

• A selection of logo artists.

• Every person in the United States.

• A selection of shoppers from different states.

• 3,800 children age 5 - 15

Samples

Biased vs. Unbiased

Biased: A non-probability sample is selected based on non-random criteria. For instance, in a convenience sample, participants are selected based on accessibility and availability

Unbiased: Everyone in the population has an equal chance of being selected and represented.

Multiple Choice

Which survey question is most likely to result in an unbiased sample?

• Which do you like better, delicious apples or boring oranges?

• Do you prefer apples, like I do, or oranges?

• Don't you prefer apples to oranges?

• Which do you prefer, apples or oranges?

Multiple Choice

1.  Carlos wants to know the favorite sport of people at his school so he asks his baseball team. What type of sample would this be?

• Biased
• Unbiased

Multiple Choice

Biased or Random?

Chloe and Danna want to determine the favorite subject of all students in the middle school. So they place every middle school student's name in a bucket and choose 30 to poll.

• Biased sample

• Random sample

Multiple Choice

To get valid results, a sample must be...

• biased

• unbiased

Multiple Choice

You want to know your town’s favorite fast-food restaurant. You randomly ask 30 people their preference as they leave a McDonald’s restaurant.

• biased

• unbiased

Multiple Choice

4. A company makes DVDs and randomly selects 25 from 1500 to test them to see if they work.

• Biased
• Unbiased

Multiple Choice

_______ is a part of a group being surveyed.

• Sample
• Population
• Random Sample
• Quartile

Multiple Choice

_________ is a sample in which each individual or object in the entire population has an equal chance of being selected.

• Sample

• Population

• Random Sample

• Quartile

Multiple Choice

_______ is the entire group of objects or individuals considered for a survey.

• Sample
• Population
• Random Sample
• Quartile

Multiple Choice

True or False: all samples lead to a good prediction about an entire population.

• True
• False

Multiple Choice

A school surveys all 7th grade boys to determine what to sell in the school store.  This sample is _________.

• Biased
• Unbiased
• Representative
• Peanut butter cups

Multiple Choice

A school survey asked 50 girls to identify their favorite items on the school cafeteria menu. This sample is ________________.

• Biased
• Unbiased
• Representative
• Numerical

Multiple Choice

A student wants to know which type of pizza the students at his high school prefer. Which option would give a unbiased, representative sample:

• Asking all the students in the hot lunch line.
• Asking 10 random students from each homeroom.
• Asking every other student who gets off a school bus.
• Asking all the 10th graders.

Multiple Choice

A toy store owner tracking how much kids spend each month on toys. Which choice best represents a population?

• All of the kids who buy toys.

• 227 wealthy kids.

• 228 boys age 7 - 15

• 235 kids from age 10 to 15.