Suppose you want to determine whether the brand of laundry detergent used or the temperature affects the amount of dirt removed from your laundry. To this end, you buy two different brand of detergent (A and B) and choose three different temperature levels (“cold”, “warm”, and “hot”). Then you divide your laundry randomly into 12 piles of equal size and dirtiness and wash them in a combination of detergent and water temperature. The results you get are as follows,

Utilizing Friedman’s Test:

a) Determine whether or not the temperature of the wash water impacted the number of grams of dirt removed.

b) Determine whether or not the brand of detergent impacted the number of grams of dirt removed.

Show the appropriate output from Minitab to support your claim and state the significance level you used.

Directions Use the Crosstabs option in the Descriptives menu to answer the questions based on the following scenario. (Be sure to select Chi-square from the Statistics submenu and Observed, Expected, Row, and Column in the Cells submenu. Assume a level of significance of .05).

Scenario

The school district recently adopted the use of e-textbooks, and the superintendent is interested in determining the level of satisfaction with e-textbooks among students and if there is a relationship between the level of satisfaction and student classification. The superintendent selected a sample of students from one high school and asked them how satisfied they were with the use of e-textbooks. The data that were collected are presented in the following table

Satisfied

Yes: Freshman (23) Sophmore (21) Junior (15) Senior (8)

No: Freshman (8) Sophmore (4) Junior (15) Senior (24)

Questions:

1. Of the students that were satisfied, what percent were Freshmen, Sophomore, Junior, and Senior? (Round your final answer to 1 decimal place).

2. State an appropriate null hypothesis for this analysis.

3. What is the value of the chi-square statistic?

4. What are the reported degrees of freedom?

5. What is the reported level of significance?

6. Based on the results of the chi-square test of independence, is there an association between e-textbook satisfaction and academic classification?

7. Present the results as they might appear in an article. This must include a table and narrative statement that reports and interprets the results of the analysis.

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 110​, and the sample standard​ deviation, s, is found to be 10.
​(a) Construct an 80​% confidence interval about μ if the sample​ size, n, is 13.
​(b) Construct an 80​% confidence interval about μ if the sample​ size, n, is 27.
​(c) Construct a 90​% confidence interval about μ if the sample​ size, n, is 13.
​(d) Could we have computed the confidence intervals in parts​ (a)-(c) if the population had not been normally​ distributed?

****** Need lower bound and upper bound *******

Suppose the National Transportation Safety Board (NTSB) wants to examine the safety of compact cars, midsize cars, and full-size cars. It collects a sample of three for each of the car types. Using the data provided below

Test, using Mood’s Median Test, whether the median pressure applied to the driver’s head during a crash test is equal for each types of car. Use α = 5%. Show the appropriate output from Minitab to support your claim and state the significance level you used.

A group of 32 rats were randomly assigned to each of 4 diets labelled (A, B,C, and D). Researchers measured the liver weight as a percentage of body weight (note: two rats escaped and another died), resulting in the following data

Using the the Krusal-Wallis test, is there evidence, at a significance level of 0.05, that the diet impacted the liver weight as a percentage of the body weight of the rats? Show the appropriate output from Minitab to support your claim. Note – you may need to modify the format of the data in order to have it work in Minitab.

1. The maximum amount of time a guest at the Holiday Inn can wait for an elevator is 4 minutes. Assuming the wait time follows a uniform distribution:

1. How long should a guest expect to wait?

2. What is the standard deviation of wait times?

3. What is the probability that a guest waits exactly 2 minutes for the elevator?

4. What is the probability that a guest waits more than 3 minutes?

5. What is the probability that a guest waits less than 90 seconds?

6. What is the probability that a guest waits between 1 minute and 2:30 for the elevator?

Use the distribution below to test that Plain M&Ms follow the stated distribution. Discuss your choice of ?. Would a different ? have changed your conclusion?

M&M states the following distribution for Plain M&Ms:
Red = 13%, Orange = 20%, Yellow = 13%, Green = 20%, Blue = 20%, Brown = 14%

Total number of plain M&M's: 665 Total number of red plain M&M's: 76 Total number of plain brown M&M's: 66 Total number of blue plain M&M's: 179 Total number of orange plain M&M's: 140 Total number of green plain M&M's: 119  Total number of yellow plain M&M's: 85

Total number of peanut M&M's: 356 Total number of red peanut M&M's: 22 Total number of peanut brown M&M's: 34 Total number of blue peanut M&M's: 55 Total number of orange peanut M&M's: 62 Total number of green peanut M&M's: 72  Total number of yellow peanut M&M's: 111

A school tracks the absences of pupils as part of a flu surveillance system. Regular reporting of absences among 29 students in grade 1 are taken, and based on these data, the long-run proportion of absences under normal conditions is estimated to be  

p = 0.076.

What is the upper control limit for a pchart of future absences from this class of size 29?

0.871

0.224

    0.611

0.230

A telemarketer is trying two different sales pitches to sell a carpet cleaning service. For his aggressive pitch, 175 people were contacted by phone and 62 of those people bought the cleaning service. For his passive pitch, 154 people were contacted by phone and 45 of those people bought the cleaning services. Does this indicate that there is any difference in population proportions of people who will buy the cleaning services depending on which sales pitch is used? Use α=0.05

a.Details given in problem

b.Assumptions if any

c.Null Hypothesis, Alt Hypothesis, and the tailed test

d.Critical Statistic

e.Compute test statistic

f.Compute p-value

g.At ___% level of significance, we have ______ evidence to reject Null Hypothesis

h.Since p-value ____ α at ___% level of significance, we have ______evidence to reject the Null Hypothesis

The retailing manager of a supermarket chain wants to determine whether product location has any effect on the sale of pet toys. Three different aisle locations are considered: front, middle, and rear. A random sample of 18 stores is selected with 6 stores randomly assigned to each aisle location. The size of the display area and price of the product are constant for all stores. At the end of a 1-month trial period, the sales volumes (in thousands of dollars) of the product in each store were as follows:

                   Aisle Location

Front              Middle                  Rear

8.8                    3.4                       4.6

7.4                    2.6                       6.0

5.6                    2.2                       4.0

6.4                    1.6                       2.8

5.2                    2.0                       2.2

4.2                    1.8                       2.8

1. At the 0.05 level of significance, is there evidence of a significant difference in mean sales among the various aisle locations?

2. What should the retailing manager conclude?

According to the Normal model ​N(0.071​,0.031​) describing mutual fund returns in the 1st quarter of​ 2013, determine what percentage of this group of funds you would expect to have the following returns. Complete parts​ (a) through​ (d) below. ​a) Over​ 6.8%? ​b) Between​ 0% and​ 7.6%? ​c) More than​ 1%? ​d) Less than​ 0%?

define U=x+y, V=x-y.

find the joint and marginal pdf of U and V

This week we were introduced to the "normal curve," also known as the bell curve. Many human factors are normally distributed, and your task for this week's discussion is two describe two examples from your own life. I'll start with my own example, which is the amount of sleep I get per night. My average is about 7 hours, and the distribution of sleep time over many nights most likely has a normal distribution. Some nights I get less than 7 hours, some nights I get more. However, the frequency of data becomes less and less, the farther it is from 7. In other words, something like 10 hours of sleep is extremely uncommon, as is only getting 4 hours. On the other hand, 6.5 hours is relatively common, as is 7.5. If I graphed the amount of sleep I got over the last 100 nights, it would approximate the shape of a bell curve.

So, what are two examples from your own life?

Betty DeRose, Inc. operates two departments, the handling department and
the packaging department. During April, the handling department reported
the following information:

                                           % complete      % complete
                                units         DM           conversion 
work in process, April 1        18,000        38%             71%
units started during April      80,000
work in process, April 30       44,000        82%             47%

The cost of beginning work in process and the costs added during April
were as follows:

                                 DM         Conversion       Total cost
work in process, April 1      $ 51,764       $152,477         $204,241
costs added during April       191,452        232,125          423,577
total costs                    243,216        384,602          627,818

Calculate the direct material unit cost using the weighted average process
costing method.

1. Using the “Rule of Thumb” guideline flow chart, what would be the best choice for a 2-Level, 2-Factor Design?
   1. Taguchi L18 Design
   2. Box-Behnkin Design
   3. Screening Design
   4. Full Factorial Design
2. A 2-level design is said to be orthogonal if:
3. It is balanced vertically
4. The dot product of all column pairs is zero
5. Both a and b
6. none of the above