Calculating Unbiased Sample

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

• biased

• unbiased

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

• Biased

• Unbiased

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

• Biased

• Unbiased

A newspaper randomly chooses 100 names from its subscriber list and then surveys those subscribers to find out if they read the sports section. This sample is ........

• unbiased

• biased

To determine how many students at Shull would attend the dance, the principal surveyed the students in Ms. Miller's math class. 10 students said they would attend and 15 said they would not attend. It can be concluded that half the students at Shull will attend the dance. Is this conclusion valid? Why or why not?

• Yes, this is a simple random sample. So the sample is unbiased.

• No, this is a convenience sample. So the sample is unbiased.

• No, this is a voluntary response sample. So the sample is biased.

• No, this is a convenience sample. So the sample is biased.

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

What type of survey sample is it when the entire population is being equally represented?

• Unbiased sample

• Biased sample