A university would like to estimate the proportion of fans who purchase concessions at the first basketball game of the season. The basketball facility has a capacity of 3,500 and is routinely sold out. It was discovered that a total of 200 fans out of a random sample of 400 purchased concessions during the game. Construct a​ 95% confidence interval to estimate the proportion of fans who purchased concessions during the game.

The​ 95% confidence interval to estimate the proportion of fans who purchased concessions during the game is ( , )

​(Round to three decimal places as​ needed.)

A university is interested in whether there's a difference between students who live on campus and students who live off campus with respect to absenteeism. Over one semester, researchers take random samples of on-campus and off-campus students and record the following number of classes each student misses.

On-campus: (3, 4, 0, 6, 2, 1, 3, 3, 5, 2, 4, 4, 6, 5, 2)

Off-campus: (6, 5, 2, 6, 2, 0, 7, 8, 1, 7, 2, 6, 5, 3, 2)

a) Using a 5% significance level, test whether or not there is a difference between the two groups.

b) Compute and interpret a 95% confidence interval for the difference between the number of classes missed by each group of students. Make sure to show your plug-ins.

c) Based on the confidence interval you created in part B, draw a conclusion about the differences between the means of the two groups.

A university dean is interested in determining the proportion of students who receive some sort of financial aid. Rather than examine the records for all students, the dean randomly selects 225 students and finds that 45 of them are receiving financial aid. Using a 95% confidence interval, what is the upper limit of the confidence interval to estimate the true proportion of students who receive financial aid.  

Using a 95% confidence interval, what is the upper limit of the confidence interval to estimate the true proportion of students who receive financial aid.

A university wants to know if students who apply to be nursing majors and accounting majors differ in terms of their ages. If there are differences, that could inform their marketing strategies.

They collect data from a random sample of 50 applicants to the nursing program and 50 application to the accounting program. They record each applicant's age in years.

In this scenario, academic major is a                            [ Select ]                       ["categorical", "quantitative"]         variable.

Age in years is a                            [ Select ]                       ["categorical", "quantitative"]         variable.

If we wanted to display these data in a graph to compare the ages of nursing and accounting majors, we could construct                            [ Select ]                       ["a bar chart", "a scatterplot", "side-by-side boxplots"]         .

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Question 31 pts

Research question: Does drinking coffee in the afternoon cause headaches?

In this study, the explanatory variable is                            [ Select ]                       ["coffee consumption", "headaches"]         and the response variable is                            [ Select ]                       ["coffee consumption", "headaches"]         .

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Question 41.5 pts

A dataset consists of the following quiz scores: 0, 8, 13, 13, 14, 14, 14, 15, 15, 15, 15, 15.

Minitab Express was used to compute the following descriptive statistics:

Given the data and descriptive statistics above, use the IQR method to identify all of the scores that are outliers.

Group of answer choices

0

8

13

14

15

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Question 51 pts

Which of the following best describes the relationship between X and Y in the scatterplot above?

Group of answer choices

Strong positive linear relationship

Strong negative linear relationship

No linear relationship

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Question 61 pts

Is the following true or false?

r x y = r y x

Where r x y is the correlation between x and y and r y x is the correlation between y and x.

Group of answer choices

True

False

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Question 71 pts

In the simple linear regression equation y ^ = a + b x, what does the term a represent?

Group of answer choices

Explanatory variable

Response variable

Slope

Y intercept

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Question 81 pts

y ^ = 5 + 4 x

Given x = 3, compute y ^.

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Question 91 pts

A high school guidance counselor used simple linear regression methods to predict his students' SAT-Math scores using their PSAT-Math scores. Using this model, Levi's predicted SAT-Math score was 480. Levi's actual SAT-Math score was 520.

Compute the residual for Levi's SAT-Math score.

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Question 101 pts

The bubble plot above was constructed using the AllCountries dataset from the Lock⁵ textbook. Each bubble represents a country. The size of each bubble represents the per-capita gross domestic product (GDP). Life expectancy (in years) is on the horizontal axis and electricity use is on the vertical axis.

Is there a relationship between life expectancy and GDP?

Group of answer choices

Yes

No

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Question 111 pts

The scatterplot with groups above displays data from the Cereal dataset from the Lock⁵ textbook. The amount of sugar in a serving is on the horizontal axis. The number of calories in a serving is on the vertical axis. The color and shape of each point represents the company.

Is there a relationship between the amount of sugar in a serving and the number of calories in a serving?

Group of answer choices

Yes, there is a relationship between sugars and calories

No, there is not a relationship between sugars and calories

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Question 121 pts

An instructor is teaching three sections of the same course: one in the morning, one in the afternoon, and one in the evening. Given the side-by-side boxplots above, which of his three sections had the highest median test score?

Group of answer choices

Morning

Afternoon

Evening

All three had the same median

A university would like to estimate the proportion of fans who purchase concessions at the first basketball game of the season. The basketball facility has a capacity of 3 comma 600 and is routinely sold out. It was discovered that a total of 200 fans out of a random sample of 500 purchased concessions during the game. Construct a​ 95% confidence interval to estimate the proportion of fans who purchased concessions during the game. The​ 95% confidence interval to estimate the proportion of fans who purchased concessions during the game is left parenthesis nothing comma nothing right parenthesis . ​(Round to three decimal places as​ needed.)

We are interested in estimating the proportion of graduates at a mid-sized university who found a job within one year of completing their undergraduate degree. We can do so by creating a 95% confidence interval for the true proportion p. Suppose we conduct a survey and find out that 340 of the 430 randomly sampled graduates found jobs within one year. Assume that the size of the population of graduates at this university is large enough so that all our conditions for normality are satisfied.

(a) What is the value of the point estimate for the proportion of graduates who found a job within one year? Round your answer to two decimal places.

(b) Use the point estimate in part (a) to calculate the standard error.

(c) For a 95% confidence interval, determine the margin of error. (Be sure that you show all your steps.) Then determine the lower and upper bounds of the interval.

(d) Which of the following is an appropriate way to interpret the confidence interval obtained in part (c)?

A. There is a 95% probability that the true proportion of people who found a job within one year of graduation is between the lower bound and the upper bound.

B. We are 95% confident that the true proportion of people who found a job within one year of graduation is between the lower bound and the upper bound.

C. We are 95% confident that the proportion of people in our sample that found a job within one year of graduation is the true proportion.

D. If we were to create many 95% confidence intervals in the same way with the same sample sizes, then all of them would contain the true proportion of the graduates who found a job within one year of graduation.

A statistics professor at a large university hypothesizes that students who take statistics in the morning typically do better than those who take it in the afternoon. He takes a random sample of 36 students who took a morning class and, independently, another random sample of 36 students who took an afternoon class. He finds that the morning group scored an average of 72 with a standard deviation of 8, while the evening group scored an average of 68 with a standard deviation of 10. The population standard deviation of scores is unknown but is assumed to be equal for morning and evening classes. Let µ1 and µ2 represent the population mean final exam scores of statistics' courses offered in the morning and the afternoon, respectively. Compute the appropriate test statistic to analyze the claim at the 1% significance level.

The professors who teach the Introduction to Psychology course at State University pride themselves on the normal distributions of exam scores. After the first exam, the current professor reports to the class that the mean for the exam was 73, with a standard deviation of 7.

a. What proportion of student would be expected to score above 80?

b What proportion of students would be expected to score between 55 and 75?

c. What proportion of students would be expected to score less than 65?

d. If the top 10% of the class receive an A for the exam, what score would be required for a student to receive an A?

e. If the bottom 10% of the class fail the exam, what score would earn a student a failing grade?

.According to a survey, high school girls average 100 text messages daily (The Boston Globe, April 21, 2010). Assume the population standard deviation is 20 text messages. Suppose a random sample of 50 high school girls is taken.

a) what is the mean daily text messages of a sample of 50 high school girls?

b) what is the standard deviation of daily text messages of a sample of 50 high school girls?

c) what is the 90th percentile of daily text messages?

.A study by Allstate Insurance Co. finds that 82% of teenagers have used cell phones while driving (The Wall Street Journal, May 5, 2010). Suppose a random sample of 100 teen drivers is taken.

a) what is the standard deviation of proportion of 100 teen drivers who use cell phone while driving?

b) we are interested in the proportion of 100 teen drivers who use cell phone while driving. What type of distribution is it- Exponential distribution, t distribution, Uniform distribution, Normal distribution?

Which one is correct statement? Choose all applied.

Which one is the correct statement? Choose all applied.