Biased vs Unbiased Samples

An automobile dealer surveys its customers to determine their level of satisfaction with the services provided at the dealership.  The sample is chosen from a list of e-mail addresses.  Is this biased or unbiased?

• Biased

• Unbiased

Karen surveyed the first seven shoppers at the produce stand. Is this sample of shoppers at the produce stand likely to be biased?

• yes

• no

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

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

• Biased

• Unbiased

• Representative

• Numerical

When a sample does not accurately represent the population it is a:

• Unbiased sample

• Biased sample

4.  Carlos wants to know the favorite sport of people at his school so he asks his baseball team.

• Biased

• Unbiased

Mrs. Boyd wants to find the average height of all her students in her classes. She decides to use the first 5 people who walk in the door. Is this a good representative sample?

• Yes

• No

A researcher wants to know the average height of students in a school. He measures the heights of students in a basketball team and uses this data as his sample. Is this sample biased or unbiased?

• Biased

• Unbiased

Answer explanation

The sample is biased because it only includes students from the basketball team, which may not represent the entire school population.

Which of the following is an example of an unbiased sample?

• Asking only your friends about their favorite ice cream flavor.

• Randomly selecting 50 students from a school's student directory to ask about their favorite subject.

Answer explanation

Randomly selecting 50 students from a school's student directory ensures a diverse and representative sample, making it an unbiased choice.

A survey is conducted by only interviewing people who have purchased a product from a specific brand. This type of sample is:

• Biased

• Unbiased

Answer explanation

The sample is biased because it only includes people who have purchased a product from a specific brand, leading to a skewed representation.