Survey Bias

At a middle school, the 7th graders will conduct a survey for where to go on a field trip. Which method will result in the least biased decision?

• to randomly ask 8th grade students who went on a field trip last year

• to randomly choose some 7th grade students to select a location

• to ask all 7th grade teachers and administrators for a location

• to ask the student council to choose a location

Reign wants to determine the most popular brand of cereal in all of Kentucky. So he polls all the houses on his street to get a sample.

• Biased

• Random

On a scale of 1-10, how would you rate my awesome and exciting class.

• Biased

• Unbiased

Why do we randomly select our samples?

• for control

• reduce bias

• so we don't get the same answers from everyone

• to eliminate confounding results

The Student Council asked every tenth student in the lunch line how they preferred to be contacted with school news. The results are shown in the table. Is this an unbiased sample? If yes, suppose there are 684 students at the school. How many can be expected to prefer E-mail?

• No, it's a biased sample

• 432

• 304

• 16

Dylan wants to know how the students at his school rate the cafeteria.  He surveyed his school's basketball team to rate the school cafeteria. Is this a biased sample of the school's population?

• Yes, because it is a convenience survey

• No, the basketball team has the smartest students

• Yes, because it's voluntary survey

• No, he should have asked the football team