1. Suppose that 25% of registered voters in North Carolina are registered Republican, 55% are registered Democrat, and 20% are registered as Independent. A local paper wants to collect a sample to help predict the next election.

• They want to take a sample of 1,500 voters.
• They randomly select 500 Republicans, 500 Democrats, and 500 Independents.

Is this an example of a simple random sample of registered voters in North Carolina?

Group of answer choices

a. Yes, since there are equal numbers in each of the three categories then it is a simple random sample.

b. Yes, each registered voter had an equal chance of being selected.

c. No, not all registered voters had an equal chance of being selected.

d. No, each group had the same number of voters. This would be impossible with a simple random sample.

2 . A survey is carried out at the University of North Carolina Chapel Hill to estimate the proportion of all graduate students living on campus in the current term. Of the 14,855 graduate students enrolled at the campus, a random sample of 300 was surveyed. What is the population?

Group of answer choices

a. All students at University of North Carolina Chapel Hill.

b. The 14,855 graduate students at University of North Carolina Chapel Hill.

c. All graduate students in North Carolina.

d. The random sample of 300 students.

3 . At Yale University, 58% of students are receiving financial aid in various forms. The school blog selects a random sample of 150 students and 65% of the students that responded that they were receiving some sort of financial aid. Which of the following statements is false?

a. The population is all of the students at Yale University.

b. Another random sample could produce a statistic different than 65%.

c. 58% is the parameter and 65% is the statistic.

d. 65% is the population and 58% is the sample.

4 . Data was collected in 50 cities across the United Kingdom on the percentage of 25 - 30 year olds in the workforce.

• Data was collected in 2015 and then again in 2019.
• Gains or losses in percent employment were measured and then conclusions were made.

What kind of design was this?

I. A sample survey

II. An observational study

III. An experimental design

a. III only

b. I Only

c. II Only

d. I and II Only

5 . Often a sample is used to gather information rather gathering data from the entire population. What is one reasonnotto use sample when gathering data?

a. If a sample is not properly chosen, they can often overestimate or underestimate the population data.

b. It can often be time consuming to gather population data.

c. It can often be costly to gather population data.

d. The sample data can often be used to estimate values for the population.

6 . Is pancakes and eggs or hot oatmeal with bacon a more filling breakfast for teenagers?

• Sixty student volunteers were randomly split into two groups and then randomly assigned their breakfast.
• One group is fed pancakes and eggs, while the other group is fed hot oatmeal and bacon.
• Each student volunteer rates his/her breakfast on scale of 1 - 10 on how hungry they were an hour later.
• If the pancake and eggs had a significantly higher average score, which of the following isnottrue?

Group of answer choices

a. Since the treatments were randomly assigned we can conclude that students in the study find pancakes and eggs to be more filling after an hour than hot oatmeal and bacon.

b. The sample size was large enough to make conclusions for the students in the group.

c. Because there was no random sampling, the results only apply to the students in the experiment.

d. Because the teenagers were randomly chosen we can conclude that all students find pancakes and eggs to be more filling after an hour than hot oatmeal and bacon.

7 . Each of the 32 NFL teams has 53 players. A sample of 75 players is to be chosen using the following method.

• Each team will be asked to place 53 pieces of paper with its players' names into a hat and randomly draw out two names.
• The two names from each team will be combined to make up the sample.

Explain how this method could result in less bias than a simple random sample. Justify your answer.

Group of answer choices

a. It results in less bias because each team will have an equal number of players represented in the sample.

b. In order for it to result in less bias we will need to take a random sample of the teams and use the whole teams chosen as part of the sample.

c. It results in less bias because this will ensure that all players chosen will all be either offensive or defensive players.

d. It does not result in less bias - the only way to reduce bias is to do simple random sample.