1.Based on the z-scores, what you say about the salaries of the employees at your company?

2. Based on the z-scores and the overall salary information, are there other criteria you would want to ask about the employees? Why would it be important to know?

3.Say you find out that Jim is the office assistant, while the other employees are all engineers. How would this change the way you look at the data?

4. Would you want to calculate the z-scores differently? Why?

5. Say you want to compare only the engineer's salaries. Calculate the z-scores below. Show your calculations. What do you notice about the new z-scores?

In a study of the accuracy of fast food​ drive-through orders, Restaurant A had 211 accurate orders and 73 that were not accurate.
a. Construct a 95​% confidence interval estimate of the percentage of orders that are not accurate. (Round to three decimal places as needed.)
b. Compare the results from part​ (a) to this 95​% confidence interval for the percentage of orders that are not accurate at Restaurant​ B: 0.235<p<0.325. What do you conclude?

Question 1 – High Technology Stocks [10 marks]

A random sample of high technology stocks was followed over a month to determine whether there has been an overall increase in the price of hi-tech stock shares (from the cost price per share a month ago to the current market price per share). Refer to Appendix A for the data and analysis.

1. [1 mark] Without reference to the data distributions but considering the manner in which the data were collected, identify two appropriate tests for determining whether there has been an overall increase in prices.

2. [2 marks] Now look at the boxplots of the data. Which of the two tests above is the most appropriate? Explain briefly with specific references to the appropriate boxplot(s).

3. [4 marks] Ignoring your answer in b), perform the most appropriate parametric test to determine if there has been an overall increase in prices. Use a 10% significance level.

4. [3 marks] Ignoring your answer in b), perform the most appropriate non-parametric test.

Appendix A

Boxplot of MarketPrice, Costprice

Two-Sample T-Test and CI: MarketPrice, Costprice

Two-sample T for MarketPrice vs Costprice

              N Mean StDev SE Mean

MarketPrice 14 26.3   27.9      7.5

Costprice    14 26.1   30.8      8.2

Difference = mu (MarketPrice) - mu (Costprice)

Estimate for difference: 0.130714

90% lower bound for difference: -14.501981

T-Test of difference = 0 (vs >): T-Value = XXXX P-Value = XXXX DF = 25

Paired T-Test and CI: MarketPrice, Costprice

Paired T for MarketPrice - Costprice

              N      Mean     StDev   SE Mean

MarketPrice 14   26.2729   27.9076    7.4586

Costprice    14   26.1421   30.8404    8.2425

Difference   14 0.130714 8.446491 2.257420

90% lower bound for mean difference: -2.917189

T-Test of mean difference = 0 (vs > 0): T-Value = XXXX P-Value = XXXX

Mann-Whitney Test and CI: MarketPrice, Costprice

              N Median

MarketPrice 14   12.35

Costprice    14    9.97

Point estimate for η1 - η2 is 0.08

90.6 Percent CI for η1 - η2 is (-7.46,12.23)

W = 204.0 (test statistic)

Test of η₁ = η₂ vs η₁ > η₂ is significant at 0.4908 (p-value)

Note: η in the output above denotes “true median”.

Wilcoxon Signed Rank Test: Diff

Test of median = 0.000000 versus median > 0.000000

             N

           for   Wilcoxon         Estimated

       N Test Statistic p-value     Median

Diff 14    14       67.0 0.190     0.8805

Give an example of a business question that could be answered through hypothesis-driven statistical methods (i.e., correlations, t-tests, regression analysis, and other methods you studied in your statistics course). These tend to be fairly simple, well-defined questions about comparisons and relationships in the data, such as which of two marketing slogans generates more sales. If you were the analyst, which statistical method would you use to answer this question?

1. Researchers obtained a sample of 36 college students who all have the same history instructor this semester. Half of the students were shown a 2-min video that claimed the purpose of education was to help students “learn how to learn” so that they can enjoy a lifetime of learning after college. other half of students were shown a 2-min video that claimed the purpose of education was to teach facts to students. After watching the 2-min videos, the students were asked to rate their history instructor using a 10-point scale, 1 = very bad teacher to 10 = very good teacher. The mean and standard deviations for each group of 18 students are provided below. Use the provided information to answer the next four questions. Use an α of .05, two tailed.

“learn to learn” Group 1: M₁ = 5.9, SD₁ = 1.8, n₁ = 18

“learn facts” Group 2: M₂ = 7.2, SD₂ = 1.7, n₂ = 18

Compute the effect size of this study.

2. Researchers obtained a sample of 36 college students who all have the same history instructor this semester. Half of the students were shown a 2-min video that claimed the purpose of education was to help students “learn how to learn” so that they can enjoy a lifetime of learning after college. The other half of students were shown a 2-min video that claimed the purpose of education was to teach facts to students. After watching the 2-min videos, the students were asked to rate their history instructor using a 10-point scale, 1 = very bad teacher to 10 = very good teacher. The mean and standard deviations for each group of 18 students are provided below. Use the provided information to answer the next four questions. Use an α of .05, two tailed.

“learn to learn” Group 1: M₁ = 5.9, SD₁ = 1.8, n₁ = 18

“learn facts” Group 2: M₂ = 7.2, SD2 = 1.7, n₂ = 18

How large is the effect size?

3. Researchers obtained a sample of 36 college students who all have the same history instructor this semester. Half of the students were shown a 2-min video that claimed the purpose of education was to help students “learn how to learn” so that they can enjoy a lifetime of learning after college. The other half of students were shown a 2-min video that claimed the purpose of education was to teach facts to students. After watching the 2-min videos, the students were asked to rate their history instructor using a 10-point scale, 1 = very bad teacher to 10 = very good teacher. The mean and standard deviations for each group of 18 students are provided below. Use the provided information to answer the next four questions. Use an α of .05, two tailed.

“learn to learn” Group 1: M₁ = 5.9, SD₁ = 1.8, n₁ = 18

“learn facts” Group 2: M₂ = 7.2, SD₂ = 1.7, n₂ = 18

Compute 95% CI for the mean difference between the “learn how to learn” and “teach facts” groups.

Two tests (A and B) for osteoporosis have the following characteristics:

• Test A has a sensitivity of 60% and a specificity of 80%.
• Test B has a sensitivity of 90% and a specificity of 90%.

If the nurse reversed the order of the testing (i.e. used Test B first and the administered Test A to those who were positive on Test B), what would happen to the net specificity?

a. decrease

b. stay the same

c. increase

d. not enough information to tell

A researcher wants to examine the production capability of three manufacturing plants that utilize different production methods of the same part in order to select a plant as a supplier for a company. The effectiveness of each plant will be measured in the number of parts it can produce in an hour. Representative hourly production amounts are recorded from each plant over a period of 12 hours and provided to the researcher.

The results of each of the three plants are as follows:

1. Use the five-step hypothesis testing process and StatCrunch to evaluate this scenario. Perform a complete analysis and interpretation of the results. If appropriate, use diagrams or graphs. Ensure your answer is detailed in all aspects. Be sure to comment on the assumptions of the ANOVA and if there are any violations. Which manufacturing plant, if any, would you recommend as the supplier?  Why?  Write up your results in APA format.

The office occupancy rates were reported for four California metropolitan areas. Do the following data suggest that the office vacancies were independent of the metropolitan area? Run a hypothesis test at alpha of 0.05. What is your conclusion?

Observed Frequencies Occupancy Status/Metropolitan Area Los Angeles San Diego San Francisco San Jose Total Occupied 160 116 192 174 642 Vacant 40 34 33 26 133 Total 200 150 225 200 775

Please explain in the excel sheet

A coffee manufacturer is interested in whether the mean daily consumption of regular-coffee drinkers is less than that of decaffeinated-coffee drinkers. Assume the population standard deviation for those drinking regular coffee is 1.21 cups per day and 1.40 cups per day for those drinking decaffeinated coffee. A random sample of 54 regular-coffee drinkers showed a mean of 4.59 cups per day. A sample of 49 decaffeinated-coffee drinkers showed a mean of 5.64 cups per day. Use the 0.100 significance level. a) Is this a one tailed or two tailed test? b) State the decision rule. c) Compute the value of the test statistic. d) What is the P-value? e) What is your decision about Ho?

Please create and solve a Factor Weighting problem for possible addition to the primer.

Thank you.

**A company developed two comercials, A and B, to advertise for their product. Two random test groups were put together each with 100 individuals and each group watched one comercial and states if they would buy the product. Group A had 25 of the individuals say they would buy the product and Group B had 20 individuals say they would buy the product. It was concluded that commercial A was more effective.**

Need to do hypothesis testing for both samples

Problem 4. Suppose the weights of seventh-graders at a certain school vary according to a Normal distribution, with a mean of 100 pounds and a standard deviation of 7.5 pounds. A researcher believes the average weight has decreased since the implementation of a new breakfast and lunch program at the school. She finds, in a random sample of 35 students, an average weight of 98 pounds.

What is the P-value for an appropriate hypothesis test of the researcher’s claim?

A poll reported that only 580 out of a total of 1649 adults in a particular region said they had a​ "great deal of​ confidence" or​ "quite a lot of​ confidence" in the public school system. This was down 5 percentage points from the previous year. Assume the conditions for using the CLT are met. Complete parts​ (a) through​ (d) below.

1. Find a 95% confidence interval for the proportion that express a great deal of confidence or quite a lot of confidence in the public​ schools, and interpret this interval. (____,____) (3 decimels

2. We are Answer ____% confident that the population proportion of adults having a great deal or quite a lot of confidence in the public schools is between Answer ___ and ____.

3. Find an  80% confidence interval and interpret it. The 80% confidence interval for the proportion that express a great deal of confidence or quite a lot of confidence in the public schools is Answer  (____,____) (Round 3 decimal places)

4. Find the width of each interval by subtracting the lower proportion from the upper​ proportion, and state which interval is wider.The width of the 95% confidence interval is (Answer) ____ and the width of the 80% confidence interval is (Answer) ____ The 95% interval is wider. ​(Round to three decimal places as​ needed.)