Please use ONLY one Excel file to complete this case study, and use one spreadsheet for each problem.

1. Develop a linear regression model to predict Wal-Mart revenue, using CPI as the only independent variable.
2. Develop a linear regression model to predict Wal-Mart revenue, using Personal Consumption as the only independent variable.
3. Develop a linear regression model to predict Wal-Mart revenue, using Retail Sales Index as the only independent variable.
4. Which of these three models is the best?  Use R-square values, Significance F values, p-values and other appropriate criteria to explain your answer.
5. Generate a scatter plot, residual plot and normal probability plot for the best model in part (d) and comment on what you see.

Identify and remove the five cases corresponding to December revenue.

6. Develop a linear regression model to predict Wal-Mart revenue, using CPI as the only independent variable.
7. Develop a linear regression model to predict Wal-Mart revenue, using Personal Consumption as the only independent variable.
8. Develop a linear regression model to predict Wal-Mart revenue, using Retail Sales Index as the only independent variable.
1. Which of these three models is the best?  Use R-square values and Significance F values to explain your answer.
10. Generate a scatter plot, residual plot and normal probability plot for the best model in part (i) and comment on what you see.
11. Comparing the results of parts (d) and (i), which of these two models is better? Use R-square values, Significance F values, p-values, scatter plot, residual plot and normal probability plot to explain your answer.

Show that under the normality assumption, the F test is equivalent to the likelihood ratio test.

A soft drink filling machine, when in perfect alignment, fills the bottles with 12 ounces of soft drink. A random sample of 36 bottles is selected, and the contents are measured. The sample yielded a mean content of 11.75 ounces with a standard deviation of 0.75 ounces.

a) Formulate the hypothesis to test to determine if the machine is in perfect adjustment.

b) Compute the value of the test statistic

c) Compute the p-value and give your conclusion regarding the adjustmentof the machine. Let a= 0.05.

On this problem the instructor has stated "For each question listed, explain how to get the correct answer. Think of this like an essay question. Or like you’re tutoring somebody. That’s what I’m really shooting for—for you to understand the material well enough to explain it to somebody else. If you can show me you can do that, you will get full credit.

So the answer has to be in essay form or comprehensive form. explaining the variables and how i got to the answer.

Chapter 15 Discussion Group Question

Gender differences in dream content are well documented (see Winget & Kramer, 1979). Suppose a researcher studies aggression content in the dreams of men and women. Each participant reports his or her most recent dreams. Then each dream is judged by a panel of experts to have low, medium, or high aggression content. The observed frequencies are shown in the following matrix:

   Aggression Content

1. Write null and alternative hypotheses (in words and notation) for both ways of framing/interpreting this data (both 'Versions') for a Chi-Square Test of Independence.

2. Using Table 15.6 from your textbook as a model, create a frequency distribution matrix for this data set. Determine the observed and expected frequencies for this data set.

3. Write out the formula for degrees of freedom. Calculate degrees of freedom for this data set.

4. Determine the critical value from Appendix B in your textbook.

5. Compute a Chi-Square Test of Independence, use an α =.05. Include the Chi-Square result and the significance value (e.g., χ2 (1, n=200) = …., p < .05)

6. Would we use Cramer’s V or Phi-Coefficient to determine effect size for this data set? Use the test you just determined to find effect size for this data set.

7. Write the results and conclusions in an APA formatted results paragraph.Page 11 of the Help Guide should be helpful.

The average age of a vehicle registered in Canada is about 97 months. If a random sample of 31 vehicles is selected, find the probability that the mean of their age is between 101 and 105 months. Assume the standard deviation for the population is 21.

Let X1, X2, and X3 represent the times necessary to perform three successive repair tasks at a service facility. Suppose they are normal random variables with means of 50 minutes, 60 minutes, and 40 minutes, respectively. The standard deviations are 15 minutes, 20 minutes, and 10 minutes, respectively.

a) Suppose X1, X2, and X3 are independent. All three repairs must be completed on a given object. What is the mean and variance of the total repair time for this object?

b) Suppose X1, X2, and X3 are independent. All three repairs must be completed on a given object. Find the probability that the total repair time is less than 180 minutes.

c) Suppose that X1, X2, and X3 are dependent so that the covariance between X1 and X2 is -150, between X1 and X3 is 60, and between X2 and X3 is -45. If all three repairs must be completed on a given object, what is the mean and variance of the total repair time for this object?

Overproduction of uric acid in the body can be an indication of cell breakdown. This may be an advance indication of illness such as gout, leukemia, or lymphoma.† Over a period of months, an adult male patient has taken eleven blood tests for uric acid. The mean concentration was x = 5.35 mg/dl. The distribution of uric acid in healthy adult males can be assumed to be normal, with σ = 1.89 mg/dl.

(a) Find a 95% confidence interval for the population mean concentration of uric acid in this patient's blood. What is the margin of error? (Round your answers to two decimal places.) lower limit upper limit margin of error

(b) What conditions are necessary for your calculations? (Select all that apply.) uniform distribution of uric acid n is large σ is unknown σ is known normal distribution of uric acid

(c) Interpret your results in the context of this problem. There is a 5% chance that the confidence interval is one of the intervals containing the population average uric acid level for this patient. The probability that this interval contains the true average uric acid level for this patient is 0.05. There is a 95% chance that the confidence interval is one of the intervals containing the population average uric acid level for this patient. The probability that this interval contains the true average uric acid level for this patient is 0.95. There is not enough information to make an interpretation.

(d) Find the sample size necessary for a 95% confidence level with maximal margin of error E = 1.14 for the mean concentration of uric acid in this patient's blood. (Round your answer up to the nearest whole number.) blood tests

A chemical manufacturer has been researching new formulas to provide quicker relief of minor pains. His laboratories have produced three different formulas, which he wanted to test. Fifteen people who complained of minor pains were recruited for an experiment. Five were given formula 1, five were given formula 2, and the last five were given formula 3. Each was asked to take the medicine and report the length of time until some relief was felt. The results below shows the time until relief is Felt.

Formula -1 : 4 8 6 9 8

Formula - 2 : 2 5 3 7 1

Formula - 3 : 6 7 7 8 6

SST = 78.4, SSE=42
(a) Write down the model and the ANOVA table to test whether there exits any differences in the time of relief exist among the three formulas? Use α =0.05.
(b) Is the Formula-1 different from Formula-3 at 5% level

Eight artists have been asked to rate the visual characteristics of a painting done first by black and white, and then in multicolor.. After each of the paintings is finished, it is rated on a scale from 1 to 5 with 1 being best and 5 being worst. The results of the rating were shown below: Can you conclude that multicolor painting is better than just black and white? (Use α = 0.05.)

The following table shows the frequency distribution for the number of personal computers sold during the past month in a sample of 40 computer stores located on the island.

Calculate the mean. Provide your answer to a decimal place.

Why do managers examine benchmarks? How can benchmarks be applied to some of the analytic techniques?

The following are daily exchange rates with the Japanese Yen quoted in Yen/Dollar.

Plot the Yen/Dollar exchange rate. Use Megastat to do an exponential smoothing using Alpha = .05, .1, .2, .5. Make a different line chart for each. Which process represents the data best. Is this process appropriate for this type of data.

Please show all work and upload your worksheet

1. Why would a researcher need to use a two-tailed test vs. a one-tailed test?

2.A scholar tests the following hypothesis:  Females have a greater number of delinquent peers than males.  In her test, she calculates a t value is -2.349.  Why would it be unnecessary to compare this test statistic to a critical t value?

Detail one instance in which regression analysis can be used in a business application. Explain what insights can be gained, limitations that must be considered, and outline one case example used in real life.

Consider a joint PMF for the results of a study that compared the number of micro-strokes a patient suffered in a year (F) and an index (S) that characterizes the stress the person is exposed to. This PMF represents the probability of a randomly picked person from the studied population having F=f micro-strokes and S=s stress index.

a) The conditional PMF for the number of strokes F given stress index S=3.


b) The expected number of strokes and the variance of this magnitude for patients with S=3?


c) The conditional PMF for strokes and stress index given event A={(S,F) /s<3 and f<2}


d) There were 3000 patients in the study. How many you expect to find that have F and S in A (same A as above)?


e) What is the average stress index in this population? (hint: the marginal probability function above may be helpful)