Multiple myeloma or blood plasma cancer is characterized Solution

Question: #8861

Question 1 of 17    1.0 Points
Multiple myeloma or blood plasma cancer is characterized by increased blood vessel formulation in the bone marrow that is a prognostic factor in survival. One treatment approach used for multiple myeloma is stem cell transplantation with the patient’s own stem cells. The following data represent the bone marrow microvessel density for a sample of 7 patients who had a complete response to a stem cell transplant as measured by blood and urine tests. Two measurements were taken: the first immediately prior to the stem cell transplant, and the second at the time of the complete response.
Patient    1    2    3    4    5    6    7
Before     158    189    202    353    416    426    441
After    284    214    101    227    290    176    290

At the .01 level of significance, is there sufficient evidence to conclude that the mean bone marrow microvessel density is higher before the stem cell transplant than after the stem cell transplant?
A.No
B.Yes
C.Cannot Determine
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Question 2 of 17    1.0 Points
Members of the general adult population volunteer an average of 4.2 hours per week. A random sample of 20 female college students and 18 male college students produced the results given in the table below. At the .01 level of significance, is there sufficient evidence to conclude that a difference exists between the mean number of volunteer hours per week for male and female college students?
   Females    Males
Sample size    20    18
Sample mean    3.8    2.5
Sample variance    3.5    2.2
A.No, because the test value 2.38 is greater than the critical value
B.No, because the test value 2.38 does not exceed the critical value
C.No, because the test value 2.90 is greater than the critical value
D.Yes, because the test value 2.90 is greater than the critical value
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Question 3 of 17 1.0 Points
Serum ferritin is used in diagnosing iron deficiency. In a study conducted recently researchers discovered that in a sample of 28 elderly men the sample standard deviation of serum ferritin was 52.6 mg/L. For 26 younger men the sample standard deviation was 84.2 mg/L. At the .01 level of significance, do these data support the conclusion that the ferritin distribution in elderly men has a smaller variance than in younger men?
A.Yes, because the test value 2.56 is greater than the critical value of 2.54
B.Yes, because the test value 0.390 is less than the critical value 2.54
C.No, because the test value 1.60 is less than the critical value of 2.54
D.Yes, because the test value 2.56 is greater than the critical value 0.394
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Part 2 of 8 -

Question 4 of 17 1.0 Points
An agent for a residential real estate company in a large city would like to be able to predict the monthly rental cost of apartments based on the size of the apartment. Data for a sample of 25 apartments in a particular neighborhood are provided in the worksheet Apartments in the Excel workbook Apartments.xlsx.

Apartments.xlsx

At the .05 level of significance determine if the correlation between rental cost and apartment size is significant.
A.Yes, there is a statistically significant linear relationship between monthly rental cost and apartment size, because the p-value for this test is less than .0001.
B.Yes, there is a statistically significant linear relationship between monthly rental cost and apartment size, because the t-test value, 7.74, is greater than the critical value 1.96.
C.No, there is not a statistically significant linear relationship between monthly rental cost and apartment size, because the sample correlation coefficient is less than .95.
D.Yes, there is a statistically significant linear relationship between monthly rental cost and apartment size, because the sample correlation coefficient 0.85 exceeds 0.50.
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Question 5 of 17 1.0 Points
Correlation is a summary measure that indicates:
A.the strength of the linear relationship between pairs of variables
B.a curved relationship among the variables
C.the rate of change in Y for a one unit change in X
D.the magnitude of difference between two variables
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Question 6 of 17 1.0 Points
The city of Oakdale wishes to see if there is a linear relationship between the temperature and the amount of electricity used (in kilowatts). Based on the data in the table below, is there a significant linear relationship between temperature and the amount of electricity used? These data are also available in the worksheet temperature in the Excel workbook Temperature.xlsx.

Temperature.xlsx
Temperature (x) 73 78 85 98 93 81 76 105
Kilowatts (y) 680 760 910 1510 1170 837 600 1800
A.Yes, the sample correlation coefficient is equal to 0.878, which provides evidence of a significant linear relationship.
B.Yes, the sample correlation coefficient is equal to 0.981, which provides evidence of a significant linear relationship.
C.No, the sample correlation coefficient is equal to 0.981, which does not provide evidence of a significant linear relationship.
D.No, the sample correlation coefficient is equal to 0.098, which does not provide evidence of a significant linear relationship.
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Question 7 of 17 1.0 Points
In choosing the “best-fitting” line through a set of points in linear regression, we choose the one with the:
A.smallest sum of squared residuals
B.largest sum of squared residuals
C.smallest number of outliers
D.largest number of points on the line
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Question 8 of 17 1.0 Points
In a simple linear regression analysis, the following sum of squares are produced:

= 500

= 100

= 400

The proportion of the variation in Y that is explained by the variation in X is:
A.20%
B.25%
C.50%
D.80%
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Part 3 of 8 -

Question 9 of 17 2.0 Points
Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker.
Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.
For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.

A field researcher is gathering data on the trunk diameters of mature pine and spruce trees in a certain area. The following are the results of his random sampling. Can he conclude, at the 0.10 level of significance, that the average trunk diameter of a pine tree is greater than the average diameter of a spruce tree?
   Pine trees    Spruce trees
Sample size    25    35
Mean trunk diameter (cm)    55    48
Sample variance    100    140

What is the test value for this hypothesis test?

Test value: Round your answer to three decimal places.

What is the critical value?

Critical value: Round your answer to three decimal places.

Part 4 of 8 -

Question 10 of 17 1.0 Points
Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker.
Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.
For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.

A company has observed that there is a linear relationship between indirect labor expense (ILE) , in dollars, and direct labor hours (DLH). Data for direct labor hours and indirect labor expense for 18 months are given in the file ILE_and_DLH.xlsx

Treating ILE as the response variable, use regression to fit a straight line to all 18 data points.

Using your estimated regression output, predict the indirect labor expenses for a month in which the company has 31 direct labor hours.

Place your answer, rounded to 1 decimal place, in the blank. Do not use any stray punctuation marks or a dollar sign. For example, 458.9 would be a legitimate entry.

Question 11 of 17 1.0 Points
Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker.
Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.
For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.

The marketing manager of a large supermarket chain would like to determine the effect of shelf space (in feet) on the weekly sales of international food (in hundreds of dollars). A random sample of 12 equal –sized stores is selected, with the following results:
Store    Shelf Space(X)    Weekly Sales(Y)
1    10    2.0
2    10    2.6
3    10    1.8
4    15    2.3
5    15    2.8
6    15    3.0
7    20    2.7
8    20    3.1
9    20    3.2
10    25    3.0
11    25    3.3
12    25    3.5

Find the equation of the regression line for these data. What is the value of the standard error of the estimate? Place your answer, rounded to 3 decimal places, in the blank. Do not use a dollar sign. For example, 0.345 would be a legitimate entry.

Part 5 of 8 -

Question 12 of 17 1.0 Points
Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker.
Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.
For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.

Two teams of workers assemble automobile engines at a manufacturing plant in Michigan. A randomsample of 145 assemblies from team 1 shows 15 unacceptable assemblies. A similar random sample of 125 assemblies from team 2 shows 8 unacceptable assemblies.

If you are interested in determining if there is sufficient evidence to conclude, at the 10% significance level, that the two teams differ with respect to their proportions of unacceptable assemblies, what is the test value you would use to conduct such a test of hypothesis?

Place your answer, rounded to 2 decimal places, in the blank. For example, 2.34 would be a legitimate entry.

Question 13 of 17 1.0 Points
Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker.
Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.
For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.

Are America's top chief executive officers (CEOs) really worth all that money? One way to answer this question is to look at the annual company percentage increase in revenue versus the CEO's annual percentage salary increase in that same company. Suppose that a random sample of companies yielded the following data:

percent change for corporation 15 12 3 12 28 6 8 2
percent change for CEO 6 17 -4 12 32 -1 7 2

Do these data indicate that the population mean percentage increase in corporate revenue is greater than the population mean percentage increase in CEO salary? Use a 5% level of significance. What is the test value that you would use to conduct this test of hypothesis? Place your answer, rounded to 3 decimal places, in the blank. For example, 2.345 would be a legitimate entry.

Part 6 of 8 -

Question 14 of 17 3.0 Points
Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker.
Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.
For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.

A special coating is applied to several scale model engine nacelle body shapes to determine if it reduces the drag coefficient. The following data are the drag coefficient before the coating is applied and after.

Model    #1    #2    #3    #4    #5    #6
Before    0.782    0.656    0.541    0.250    0.323    0.888
After    0.668    0.581    0.532    0.241    0.334    0.891

Perform a hypothesis test to determine if there is evidence at the 0.05 level of significance to support the claim that the coating reduces the drag coefficient.

What is the test value for this hypothesis test?

Answer: Round your answer to two decimal places.

What is the P-value for this hypothesis test?

Answer: Round your answer to three decimal places.

What is your conclusion for this test? Choose one.

1. There is sufficient evidence to show the coating reduces the drag coefficient.
2. There is not sufficient evidence to show that the coating reduces the drag coefficient.
3. There is sufficient evidence to show that the drag coefficient changed after the coating was applied.
4. There is sufficient evidence to show that the drag coefficient increased after the coating was applied.

Answer: Enter only a 1, 2, 3 or 4 for your answer.

Part 7 of 8 -

Question 15 of 17 1.0 Points
When testing the equality of two population variances, the test statistic is the ratio of the population variances; namely .
True
False
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Part 8 of 8 -

Question 16 of 17 1.0 Points
A negative relationship between an explanatory variable X and a response variable Y means that as X increases, Y decreases, and vice versa.
True
False
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Question 17 of 17 1.0 Points
To help explain or predict the response variable in every regression study, we use one or more explanatory variables. These variables are also called predictor variables or independent variables.
True
False

Solution: #8886

Multiple myeloma or blood plasma cancer is characterized Solution

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