Chipotle Mexican Grill continues to suffer from perception issues after a string of outbreaks, including E.coli, worried customers about the safety of eating at the fast-casual chain. Chipotle’s strategy for getting customers back into its restaurants was to give away free tacos, burritos, and chips. And while its customer survey scores are improving, Chipotle is still operating at a loss. What concepts, constructs, and operational definitions should any future research deal with?

Management of a soft-drink bottling company wants to develop a method for allocating delivery costs to customers. Although one cost clearly relates to travel times within a particular route, another variable cost reflects the time required to unload the cases of soft drink at the delivery point. A sample of 20 deliveries within a territory was selected. The delivery time and the number of cases delivered were recorded. Develop a regression model to predict delivery time based on the number of cases delivered. Use the least-square method to calculate the regression coefficients, b0 and b1. Showing all formulas and equations a) Write your regression equation. b) Determine the coefficient of determination, r2, and explain it meaning in this problem. c) Perform a residual analysis. Is there any evidence of patterns in the residuals? Explain.

For this problem, carry at least four digits after the decimal in your calculations. Answers may vary slightly due to rounding.

A random sample of 5913 physicians in Colorado showed that 3062 provided at least some charity care (i.e., treated poor people at no cost).

(a) Let p represent the proportion of all Colorado physicians who provide some charity care. Find a point estimate for p. (Round your answer to four decimal places.)


(b) Find a 99% confidence interval for p. (Round your answers to three decimal places.)

Give a brief explanation of the meaning of your answer in the context of this problem.

1% of the confidence intervals created using this method would include the true proportion of Colorado physicians providing at least some charity care.99% of the confidence intervals created using this method would include the true proportion of Colorado physicians providing at least some charity care.    1% of all confidence intervals would include the true proportion of Colorado physicians providing at least some charity care.99% of all confidence intervals would include the true proportion of Colorado physicians providing at least some charity care.

(c) Is the normal approximation to the binomial justified in this problem? Explain.

No; np < 5 and nq > 5.Yes; np > 5 and nq > 5.    No; np > 5 and nq < 5.Yes; np < 5 and nq < 5.

The breaking strengths of cables produced by a certain manufacturer have a standard deviation of 91 pounds. A random sample of 90 newly manufactured cables has a mean breaking strength of 1700 pounds. Based on this sample, find a 95% confidence interval for the true mean breaking strength of all cables produced by this manufacturer. Then complete the table below. Carry your intermediate computations to at least three decimal places. Round your answers to one decimal place. (If necessary, consult a list of formulas.)

The auditor for a large corporation routinely monitors cash disbursements. As part of this process, the auditor examines check request forms to determine whether they have been properly approved. Improper approval can occur in several ways. For instance, the check may have no approval, the check request might be missing, the approval might be written by an unauthorized person, or the dollar limit of the authorizing person might be exceeded.

(a) Last year the corporation experienced a 5 percent improper check request approval rate. Since this was considered unacceptable, efforts were made to reduce the rate of improper approvals. Letting p be the proportion of all checks that are now improperly approved, set up the null and alternative hypotheses needed to attempt to demonstrate that the current rate of improper approvals is lower than last year's rate of 5 percent. (Round your answers to 2 decimal places.)

H₀: p > ______ versus H_a: p < ______.

(b) Suppose that the auditor selects a random sample of 617 checks that have been approved in the last month. The auditor finds that 19 of these 617 checks have been improperly approved. Calculate the test statistic. (Round your answers to 2 decimal places. Negative value should be indicated by a minus sign.)

(c) Find the p-value for the test of part b. Use the p-value to carry out the test by setting a equal to .10, .05, .01, and .001. Interpret your results. (Round your answer to 4 decimal places.)

p-value                 

Reject H₀ at α = (Click to select).1, and .05/ .1, .05 and .01/ .10, .05, .01, and .001/ none.

What is a hypothesis? Provide an example of a "null hypothesis" and an "alternative hypothesis"

A recent poll stated that if the presidential election were held today, the results would be as follows:

Candidate A: 33%

Candidate B: 33%

Undecided: 34%

Margin of error is 20%

Based on our class discussions to date, what conclusion would you draw from this data?

Researchers at Consumer Reports recently found that fish are often mislabeled in grocery stores and restaurants. They are interested to know, however, if the proportion of mislabeling varies by type of fish. They collected data on 400 packages of tuna and 300 packages of mahi mahi and found that 110 and 95 were mislabeled, respectively.

a. What are the point estimates for the proportion of tuna and mahi mahi that are mislabeled?

b. Provide a 95% confidence interval estimate of the difference between the proportion of tuna and mahi mahi that is mislabeled.

c. Based on your answer to (b), would you say the rate of mislabeling is different for tuna and mahi mahi? Explain your answer.

d. Now, let’s say we want to test whether the proportion of tuna mislabeled is lower than the proportion of mislabeled mahi mahi. Assuming a 99% confidence level, work through your hypothesis testing procedure below.

Discuss the differences in a regression model between making the random error being multiplicative and making the random error being additive regarding how you approach estimation of the model coefficient(s), how you apply linearization for estimating the model coefficient(s), and how you obtain starting values for estimation of the model coefficient(s).

Researchers studied a random sample of high school students who participated in interscholastic athletics to learn about the risk of lower-extremity injuries (anywhere between hip and toe) for interscholastic athletes. Of 998 participants in girls' soccer, 77 experienced lower-extremity injuries. Of 1660 participants in boys' soccer, 159 experienced lower-extremity injuries.

Write a two-way table of observed counts for gender and whether a participant had a lower-extremity injury or not.

(b) Determine a two-way table of expected counts for these data. (Round the answers to one decimal place where it is needed.)

(c) Show calculations verifying that the value of the chi-square statistic is 2.67. Chi-square = (77-88.6)2/ + (921- )2/909.4 + ( -147.4)2/147.4 + (1501- )2/ = 1.52 + 0.15 + + 0.09 = 2.67

A hospital employs 338 nurses and 35​% of them are male. How many male nurses are​ there? b. An engineering firm employs 168 engineers and 109 of them are male. What percentage of these engineers are​ female? c. A large law firm is made up of 65​% male​ lawyers, or 164 male lawyers. What is the total number of lawyers at the​ firm?

I'm having a pretty difficult time with these types of problems and I'd really appreciate it if someone could show me how to go about doing this one, thank you!

1. Consider the population of {32, 34, 37, 39}

a) Find the mean, variance, and standard deviation

b) Suppose the sample size n=2 is randomly chosen with replacement from this population, List the 16 possible samples of size n=2

c) Fill out the table

d) How do the average of all of the 16 sample means, sample variance, and sample standard deviation compare to the population mean, population variance, and population standard deviation?

According to Harper’s magazine, the time spend by kids in front of the television set per year can be modeled by a normal distribution with a mean equal to 1500 hours and a standard deviation equal to 250 hours. If 25 kids are randomly selected from this population, what is the probability that the average of their times spent watching television is at least 1650 hours per year?

The polling organization Ipsos conducted telephone surveys in March of 2004, 2005 and 2006. In each year, 1001 people age 18 or older were asked about whether they planned to use a credit card to pay federal income taxes that year. The data are given in the accompanying table. Is there evidence that the proportion falling in the three credit card response categories is not the same for all three years? Test the relevant hypotheses using a .05 significance level. (Use 2 decimal places.)

χ² =  
P-value interval

p < 0.0010.001 ≤ p < 0.01    0.01 ≤ p < 0.050.05 ≤ p < 0.10p ≥ 0.10

1.Conduct an analysis and hypothesis test of your choice on the data you collected. Write a 250-500 word research summary of the findings generated in the assignments for Topics 2 through 5. The research summary should address the following.

a. Explain what type of analysis and hypothesis test was conducted on the data collected.

b. Summarize the survey results based on the results of the data you analyzed.

c. Include the Excel analysis as part of the document.

Data available below: Time stamp 1.  If given the opportunity to work from home would you? Yes/No/Maybe

2. Do you consider working from home more of a employee convenience or employer benefit?

3. Who benefits more from the "Work from Home" opportunity?