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Stats Quiz 5

Stats Quiz 5

Daniel Kevins

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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?

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Question 2 of 17

1.0 Points

Patient	1	2	3	4	5	6	7
Before	158	189	202	353	416	426	441
After	284	214	101	227	290	176	290

Suppose you wanted to conduct a test of hypothesis to determine if there is sufficient evidence to conclude that the mean bone marrow microvessel density is higher before the stem cell transplant than after the stem cell transplant? What is the p-value associated with the test of hypothesis you would conduct?

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Question 3 of 17

1.0 Points

An investor wants to compare the risks associated with two different stocks. One way to measure the risk of a given stock is to measure the variation in the stock’s daily price changes.

In an effort to test the claim that the variance in the daily stock price changes for stock 1 is different from the variance in the daily stock price changes for stock 2, the investor obtains a random sample of 21 daily price changes for stock 1 and 21 daily price changes for stock 2.

The summary statistics associated with these samples are: n₁ = 21, s₁ = .725, n₂ = 21, s₂ = .529.

If you compute the test value by placing the larger variance in the numerator, at the .05 level of significance, would you conclude that the risks associated with these two stocks are different?

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Part 2 of 8 –

Question 4 of 17

1.0 Points

The regression line y’ = -3 + 2.5 X has been fitted to the data points (28, 60), (20, 50), (10, 18), and (25, 55). The sum of the squared residuals will be:

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Question 5 of 17

1.0 Points

If an estimated regression line has a Y-intercept of –7.5 and a slope of 2.5, then when X = 3, the actual value of Y is:

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Question 6 of 17

1.0 Points

Correlation is a summary measure that indicates:

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Question 7 of 17

1.0 Points

In regression analysis, the variable we are trying to explain or predict is called the

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Question 8 of 17

1.0 Points

Outliers are observations that

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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	30	35
Mean trunk diameter (cm)	45	39
Sample variance	120	140

What is the test value for this hypothesis test?

Test value:

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Daniel Kevins

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