Biased vs Unbiased Practice

To determine the most popular children’s programs, a television station asks parents to call in and complete a phone survey.

• Biased Sample

• Unbiased Sample

To determine how often people eat out, every tenth person entering a Chinese restaurant is surveyed.

• Biased Sample

• Unbiased Sample

A homeowner divides their backyard into 5 sections, and randomly removes soil from sections.

• Biased

• Unbiased

A public library asked every 10th person who entered to name the type of book they were getting.

• Biased

• Unbiased

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

• Biased

• Unbiased

To see who has a computer at home the front office chooses 10 students randomly per grade to ask.

• Biased

• Unbiased

A senator wants to know how she is doing in her position. She sends a survey to 1000 registered voters in her party.

• Biased

• Unbiased

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

• 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

To determine how many students plan to attend the school musical, Maria surveys 100 random people in the hallway.

• Biased

• Unbiased