Sampling to Draw Inferences

Darrien surveys 60 of the actors theater class. He concludes that 8 out of 15 actors have previous acting experience. What is the sample size?

• 60

• 8

• 15

• 53

What is the interquartile range for the Checkers Club?

• 4

• 5

• 10

• 11

Becky wants to know if she should sell cranberry muffins at her bakery. She asks every customer who buys blueberry muffins if they would buy cranberry muffins. Is this a representative sample?

• Yes, it does not include people who would buy cranberry muffins but do not like blueberry muffins

• No, it does not include people who would buy cranberry muffins but do not like blueberry muffins

• Yes, it does include people who would buy cranberry muffins but do not like blueberry muffins

• No, it does include people who would buy cranberry muffins but do not like blueberry muffins

Which data set shows a greater spread?

• Chess Club

• Checkers Club

• They have the same spread.

• You cannot tell from the box plots. 

Zara wants to know how teachers in the local school district feel about extending the school day to 30 minutes longer. Which method will produce a representative sample and therefore provide valid inference?

• Survey all the teachers who have publicly protested or supported the proposal.

• Survey the first 30 teachers who arrive at Zara's school in the morning.

• Survey a random sample of 30 teachers within the school district.

• Survey a random sample of 30 teachers and parents of kids within the district.

To get valid (true) results, a sample must be...

• biased

• unbiased (representative)

Disneyland often surveys its guests as they exit a restaurant during their visit. The surveyor stands at the restaurant exit, counts the number of people leaving, and surveys every 25th guest.

This is a form of:

• Simple Random Sample

• Convenience Sampling

• Voluntary Response

• Systematic Sampling

What type of sampling makes for a valid inferences

• Random sampling

• Representative sampling

When you do not have the resources to study every member of the population, do this ...

• absence of a sample

• do best with an invalid inference

• create a sample

• do without a sample

If the population is ALL 7th Graders Then you want to take a sample from ALL 7th graders. A sample is part of the population but not all of it. Select the one below that is true

• A sample is a smaller group selected from the population

• A sample is the entire population

• A sample is a larger group than the population

• A representative sample is not related to the population