Bias and Samples

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

Ana wants to know the average student’s opinion of the tardy policy at her school. Which group of students should she survey in order to achieve the most accurate results?

• thirty students who are often tardy
• thirty students who are rarely tardy
• thirty of her friends
• thirty randomly selected students from her school

The population describes:

• The group of people, objects or events being surveyed
• a part of the group being surveyed
• the whole world
• the school

Mrs. Trahan samples her class by picking 10 numbers from her hat and each number is assigned to a student. This is ______________ random sampling.

• Systematic
• Simple
• Stratified
• Cluster

Source of bias in which people CHOOSE to respond and usually only people with very strong opinions respond

• Response Bias
• Undercoverage
• Convenience Sampling
• Voluntary Response

Source of bias that occurs when you ask people who are EASY to ask

• Response Bias
• Convenience Sampling
• Nonresponse
• Voluntary Response

To learn about teenagers' opinions of different social media platforms, a survey was given to students of one high school. This sample is...

• representative

• biased

• random

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 
• Unbiased
• convenience

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

Do you want a delicious salad for lunch or the usual sandwich?

• Biased

• Not Biased