Exam 7: Survey Sampling and Inference

Suppose that you and a friend read the following statement in a news report, "A recent pollfound that 54% of voters, give or take 3%, plan to vote for candidate X in the next election(with a confidence level of 95%)." Your friend then makes the statement, "Hey, look, there'sa 95% chance that somewhere between 51% and 57% of voters plan to vote for candidateX!" How would you explain to your friend why his statement is incorrect, be sure toprovide your friend with the correct interpretation of the confidence interval.

The collection of the ages of all the U.S. first ladies when they married is a_{--------------------} .

If it is being used to make inferences about a population, a good statistic (or estimator) should

Suppose that Illinois lawmakers survey 130 randomly selected registered voters to see if they favorcharging a deposit on aluminum cans to encourage recycling. The lawmakers believe thepopulation proportion in favor of changing the law is 93% (based on historical data and previousvotes). Which of the following conditions for the Central Limit theorem arenotmet?

Which of the following statements is true about the confidence interval for a population proportion?

Use the following information to answer the question. A pescatarian is a person who eats fish and seafood but no other animal. An event planner does some research and finds that approximately 2.75% of the people in the area where a large event is to be held are pescatarian. Treat the 250 guests expected at the event as a simple random sample from the local population of about 150,000. -Suppose the event planner assumes that only 1.6% of the guests will be pescatarian so he orders 4pescatarian meals. What is the approximate probability that he will havetoo manypescatarianmeals? Round to the nearest thousandth.

Use the following information to answer the question. A pescatarian is a person who eats fish and seafood but no other animal. An event planner does some research and finds that approximately 2.75% of the people in the area where a large event is to be held are pescatarian. Treat the 250 guests expected at the event as a simple random sample from the local population of about 150,000. -On average, what proportion of the guests would be expected to be pescatarian, give or take how many? Round to the nearest whole person.

Frances is interested in whether students at his college would like to see a portion of the campuspreserved as green space. Using student numbers, he randomly contacts 300 students and receivesa response from 75. Of those who responded, 64% favored the preservation of green space oncampus. This scenario is describing what type of sampling bias?

Suppose that Michigan lawmakers survey 500 randomly selected registered voters to see ifthey favor an extension of the fall duck hunting season. The lawmakers believe thepopulation proportion in favor of extending the duck hunting season is 45% (based onhistorical data and previous votes). State the three conditions of the Central Limit Theoremand explain whether each condition is satisfied in this scenario.

A random sample of 830 adult television viewers showed that 52% planned to watch sportingevent X. The margin of error is 3 percentage points with a 95% confidence. Does the confidenceinterval support the claim that the majority of adult television viewers plan to watch sporting eventX? Why?

Max is interested in whether there is community interest in having local musicians perform musicin the park in the evenings during the summer. Max goes to the park for several evenings in a rowand asks people visiting the park whether they would like to hear music in the evening. Out of the200 people he surveys, 58% respond favorably. This scenario is describing what type of samplingbias?

Can the way a survey question is asked affect the sample results? Explain why such asample is or is not reflective of the population.

Use the following information to answer the question. A pollotarian is a person who eats poultry but no red meat. Awedding planner does some research and finds that approximately 3.5% of the people in the area where a large wedding is tobe held are pollotarian. Treat the 300 guests expected at the wedding as a simple random sample from the local population ofabout 200,000. -On average, what proportion of the guests would be expected to be pollotarian, give or take how many? Round to the nearest whole person.

Suppose the event planner assumes that only 0.8% of the children attending the event willbe lactose intolerant so he orders 2 lactose-free meals. What is the approximate probability that he will have too many lactose-free meals? Round to the nearest thousandth.

Fill in the blank to complete the statement. -Suppose that the age of all the U. S. vice presidents when they took office was recorded. The collection of the ages of all the U. S. vice presidents when they took office is a .

Use the following information to answer the question. In a recent poll of 1100 randomly selected home delivery truck drivers, 26% said they had encountered an aggressive dog on the job at least once. -What is the standard error for the estimate of the proportion of all home delivery truck drivers who have encountered an aggressive dog on the job at least once? Round to the nearest ten-thousandth.

Use the following information to answer the question. A marble manufacturer advertises that its bags of marbles will contain25% "milky-white" marbles. Suppose that a bag containing 80 marbles is inspected. -What value should we expect for our sampling percentage of milky-white marbles? Howmany marbles would this be? Round to the nearest whole marble.

Use the following information to answer the question. In a recent poll of 1100 randomly selected home delivery truck drivers,26% said they had encountered an aggressive dog on the job at least once. -What is the margin of error, using a 95% confidence level, for estimating the true populationproportion of home delivery truck drivers who have encountered an aggressive dog on the job atleast once? (Round to the nearest thousandth)

There are four colors in a bag containing 500 plastic chips. It is known that 28% of the chips are green. On average, how many chips from a random sample of 50 (with replacement) would be Expected to be green?

Use the following information to answer the question. A pollotarian is a person who eats poultry but no red meat. Awedding planner does some research and finds that approximately 3.5% of the people in the area where a large wedding is tobe held are pollotarian. Treat the 300 guests expected at the wedding as a simple random sample from the local population ofabout 200,000. -Suppose the wedding planner assumes that only 3% of the guests will be pollotarian so she orders 9pollotarian meals. What is the approximate probability that she will havetoo manypollotarianmeals? Round to the nearest thousandth.