researcher wishes to estimate the proportion of adults who have​ high-speed Internet access. What size sample should be obtained if she wishes the estimate to be within 0.03 with 95​% confidence if ​(a) she uses a previous estimate of 0.32​? ​(b) she does not use any prior​ estimates?

A report just came out that stated that 22.9% of all Americans say that vanilla is their favorite ice cream, 23.4% say that chocolate is their favorite, 8% favor butter pecan, 8.7% favor strawberry, and the rest have other favorites. An ice cream shop owner thinks that her customers are not like the rest of America. The table below shows the results of 1000 of her patrons' ice cream selections. What can be concluded at the αα = 0.05 significance level?

Complete the table by filling in the expected frequencies. Round your answers to the nearest whole number.
Frequencies of Favorite Ice Cream

OutcomeFrequencyExpected Frequency

Vanilla243

Chocolate220

Butter Pecan85

Strawberry67

Other385

What is the correct statistical test to use?
Select an answer Paired t-test Homogeneity Independence Goodness-of-Fit

What are the null and alternative hypotheses?
H0:H0:

The distribution of favorite ice cream for customers at her shop is not the same as it is for Americans in general.

Favorite ice cream and where the ice cream is purchased are independent.

Favorite ice cream and where the ice cream is purchased are dependent.

The distribution of favorite ice cream for customers at her shop is the same as it is for Americans in general.

H1:H1:

The distribution of favorite ice cream for customers at her shop is not the same as it is for Americans in general.

The distribution of favorite ice cream for customers at her shop is the same as it is for Americans in general.

Favorite ice cream and where the ice cream is purchased are dependent.

Favorite ice cream and where the ice cream is purchased are independent.

The degrees of freedom =

The test-statistic for this data =  (Please show your answer to three decimal places.)

The p-value for this sample = (Please show your answer to four decimal places.)

The p-value is Select an answer greater than less than (or equal to)  αα

Based on this, we should Select an answer reject the null accept the null fail to reject the null

Thus, the final conclusion is...

There is insufficient evidence to conclude that the distribution of favorite ice cream for customers at her shop is not the same as it is for Americans in general.

There is sufficient evidence to conclude that the distribution of favorite ice cream for customers at her shop is the same as it is for Americans in general.

There is sufficient evidence to conclude that favorite ice cream and where the ice cream is purchased are dependent.

There is insufficient evidence to conclude that favorite ice cream and where the ice cream is purchased are dependent.

There is sufficient evidence to conclude that the distribution of favorite ice cream for customers at her shop is not the same as it is for Americans in general.

A recent national report states the marital status distribution of the male population age 18 or older is as follows: Never Married (32.8%), Married (54.2%), Widowed (2.7%), Divorced (10.3%). The table below shows the results of a random sample of 1928 adult men from California. Test the claim that the distribution from  California is as expected at the αα = 0.01 significance level.

Complete the table by filling in the expected frequencies. Round to the nearest whole number:
Frequencies of Marital Status

OutcomeFrequencyExpected Frequency

Never Married649

Married1047

Widowed51

Divorced181

What is the correct statistical test to use?
Select an answer Independence Paired t-test Homogeneity Goodness-of-Fit

What are the null and alternative hypotheses?
H0:H0:

Marital status and residency are independent.

Marital status and residency are dependent.

The distribution of marital status in California is the same as it is nationally.

The distribution of marital status in California is not the same as it is nationally.

H1:H1:

The distribution of marital status in California is not the same as it is nationally.

Marital status and residency are dependent.

The distribution of marital status in California is the same as it is nationally.

Marital status and residency are independent.

The degrees of freedom =

The test-statistic for this data =  (Please show your answer to three decimal places.)

The p-value for this sample = (Please show your answer to four decimal places.)

The p-value is Select an answer less than (or equal to) greater than  αα

Based on this, we should Select an answer accept the null reject the null fail to reject the null

Thus, the final conclusion is...

There is insufficient evidence to conclude that marital status and residency are dependent.

There is sufficient evidence to conclude that the distribution of marital status in California is the same as it is nationally.

There is sufficient evidence to conclude that the distribution of marital status in California is not the same as it is nationally.

There is insufficient evidence to conclude that the distribution of marital status in California is not the same as it is nationally.

There is sufficient evidence to conclude that marital status and residency are dependent.

The paired values represent the weights (carats) and prices (dollars) of randomly selected diamonds.

39. Compute the least squares regression line for the predicted price for a given weight.

40. Calculate the correlation coefficient between the two variables.

Please show work using excel functions!

The VP of HR for a large company is interested in the distribution of sick-leave hours for employees at the company. A recent study revealed that the distribution was consistent with a normal model, with a mean of 58 hours per year, and a standard deviation of 14 hours. An office manager of one division believes that during the past year, two of the division’s employees have taken excessive sick leave. One took 74 hours and the other used 90 hours. What would you conclude about the division manager’s claim, and why?

Two formulations of a certain coating, designed to inhibit corrosion, are being tested. For each of eight peoples, half the pipe is coated with formulation A and the other half is coated with formulation B. Each pipe is exposed to a salt environment for 500 hours. Afterward, the corrosion loss is measured for each formulation on each pipe and the results are shown below. Can you conclude that the mean amount of corrosion differs between the two formulation? Setup the test and show your p-value.

Consider the following data:

Number of Deaths in the U.S. by Drug Overdose

Year   2000 2001 2002 2003 2004 2005 2006 2007 2008

Deaths 17,046 17,511 14,317 13,372 17,767 14,526 11,155 18,657 16,644

Step 2 of 2 : Find the three-period moving average for the year 2007. If necessary, round your answer to one decimal place.

10. According to a 2018 report, the mean amount of data used by all smartphone users with unlimited data plans was 4.87 GB per month. A company would like to determine if the mean amount of data used per month by smartphone user is different that it was in 2018. In order to investigate the issue, random sample of 900 smartphone users was selected.

Determine the null and alternative hypotheses:

H0=

HA=

A Type I error in the context of this problem would be:

A Type II error in the context of this problem would be:

11. According to a report published last year by Pew Research, 23% of all American adults lived in a middle-class household. This year, an economist collected data from a random sample of 1210 American adults in order to determine if the percent of American adults who live in a middle-class household is lower than 23%. State the hypotheses and explain the possible Type 1 and Type 2 errors.

Determine the null and alternative hypotheses:

H0=

HA=

A Type I error in the context of this problem would be:

A Type II error in the context of this problem would be:

A researcher is evaluating whether a new intervention affects the average reported anxiety symptoms in a sample of 49 college students. A survey from the previous semester found that the population reported a mean anxiety score of 22 with a standard deviation of 7. The sample completes the same measure of anxiety, with an average score of 20. The researcher sets their alpha level at .05 and performs a two-tailed test to determine whether anxiety increases or decreases after the intervention. Calculate effect size using Cohen’s d. Show all of your calculations for full credit.

1)

An App developing company recently developed a new game that can be played on the iPhones. The company wants to run a survey on the satisfaction rate on the game. They randomly send out a survey to 600 iPhone users who have downloaded the app and 498 of them are happy with the game.

What is a 95% Confidence interval for the true proportion that are satisfied with the app companies game?

Group of answer choices

(.76, .89)

(.79, .87)

(.83, .88)

(.80, .86)

2)

Referring back to the scenario in the previous few questions, suppose the app company wanted to make a 99% confidence interval for the true satisfaction rate with a margin of error of 2%.

How big a sample would they need to take?

Group of answer choices

4147.36

3382

3381.42

4148

3)

A video game streamer with a lot of subscribers (say 20,000) wants to switch to a new video game. The streamer will only do this if there is evidence that more that 75% of his subscriber base would be interested in watching the new game. He randomly selects 800 subscribers and asks if they would be interested in watching the new game. 632 say yes. We will do a hypothesis test to assess whether the streamer should switch games.

Identify the correct Null and Alternative Hypotheses.

Group of answer choices

Ho: p = .75 vs Ha: p < .75

Ho: p > .75 vs Ha: p = .75

Ho: p = .79 vs Ha: p > .79

Ho: p = .75 vs Ha: p > .75

4)

A video game streamer with a lot of subscribers (say 20,000) wants to switch to a new video game. The streamer will only do this if there is evidence that more that 75% of his subscriber base would be interested in watching the new game. He randomly selects 800 subscribers and asks if they would be interested in watching the new game. 632 say yes. We will do a hypothesis test to assess whether the streamer should switch games.

The conditions for a hypothesis test are met in this problem. What is the value of the test statistic? (round to two decimals)

Group of answer choices

2.27

1.96

2.78

2.61

5)

A video game streamer with a lot of subscribers (say 20,000) wants to switch to a new video game. The streamer will only do this if there is evidence that more that 75% of his subscriber base would be interested in watching the new game. He randomly selects 800 subscribers and asks if they would be interested in watching the new game. 632 say yes. We will do a hypothesis test to assess whether the streamer should switch games.

Using the test statistic you calculated in the previous question, give the p-value.

Group of answer choices

.0045

.0001

.0056

.0088

A simple random sample of size n is drawn from a population that is normally distributed. The sample​ mean, x overbar​, is found to be 115​, and the sample standard​ deviation, s, is found to be 10. ​(a) Construct a 96​% confidence interval about mu if the sample​ size, n, is 12. ​(b) Construct a 96​% confidence interval about mu if the sample​ size, n, is 21. ​(c) Construct a 98​% confidence interval about mu if the sample​ size, n, is 12. ​(d) Could we have computed the confidence intervals in parts​ (a)-(c) if the population had not been normally​ distributed?

Give one example of analyses using hypothesis testing framework and identify a null and alternative hypothesis

Using excel with formulars

for binomial random variable X with n=10, p=0.3, plot its pdf and cdf; then simulate from it a sample of size N=2000, plot its histogram (relative frequency), and cumulative frequency.

Suppose that, for students who are enrolled in college algebra, 72 percent are freshman, 40 percent are female, and 25 percent are female and freshman. Your answers should be entered as decimals and rounded to three decimal places.

(A) one student will be selected at random. What is the probability that the selected student will be a freshman or female (or both)? ___

(B) one student will be selected at random. What is the probability that the selected student will not be a freshman? ___

(C) two students will be independently selected at random. What is the probability that both of the selected students will be female? __