Question 1

Would it be better for customers for a year to have a negative residual or a positive
residual from this model? Explain.

Accepted Answer

It would be better for customers to have

Question 2

You are given the following costs to build a square deck for your house: $$\begin{array} { | l | c | c | c | c | c | c | c | c | c | c | c | c | } 
\hline \text { Width (ft) } & 4 & 5 & 6 & 7 & 8 & 9 & 10 & 11 & 12 & 13 & 14 & 15 \
\hline \text { Cost (\$) } & 150 & 255 & 350 & 500 & 650 & 800 & 1000 & 1200 & 1450 & 1700 & 1950 & 2250 \
\hline
\end{array}$$ 
a. Use re-expressed data to create a model that predicts the cost of the deck based on the
width.
b. Why do you think that your model is appropriate?
c. Find the predicted cost of a square deck that is 10.5 feet wide.
d. Is it reasonable to use this model to predict the cost of a square deck that is 20 feet wide?
Explain.

Accepted Answer

a. Using the square root of the costs, w

Question 3

Which is true about a 99% confidence interval based on a given sample?
I. The interval contains 99% of the population.
II. Results from 99% of all samples will lie in this interval.
III. The interval is wider than a 95% confidence interval would be.

Accepted Answer

A)  II and III only 
B)  III only 
C)  II only 
D)  I only 
E)  none of these 
A)  II and III only 
B)  III only 
C)  II only 
D)  I only 
E)  none of these

Question 4

Which is true about a 95% confidence interval based on a given sample?
I. The interval contains 95% of the population.
II. Results from 95% of all samples will lie in the interval.
III. The interval is narrower than a 98% confidence interval would be.

Accepted Answer

A)  none of these 
B)  III only 
C)  II only 
D)  I only 
E)  II and III only 
A)  none of these 
B)  III only 
C)  II only 
D)  I only 
E)  II and III only

Question 5

Describe how you will use a random number table to conduct this simulation.

Accepted Answer

Since @#LAT-DLM& of the batteries come off of the

Question 6

What is the probability that none of the first three customers gets more than a 30%
discount?

Accepted Answer

@#LAT-DLM&
@#LAT-DLM& three in

Question 7

Which statement correctly compares t-distributions to the normal distribution?
I. t distributions are also mound shaped and symmetric.
II. t distributions have less spread than the normal distribution.
III. As degrees of freedom increase, the variance of t distributions becomes smaller.

Accepted Answer

A)  I, II, and III 
B)  I only 
C)  II only 
D)  I and III only 
E)  I and II only 
A)  I, II, and III 
B)  I only 
C)  II only 
D)  I and III only 
E)  I and II only

Question 8

After conducting a survey of his students, a professor reported that "There appears to be a
strong correlation between grade point average and whether or not a student works."
Comment on this observation.

Accepted Answer

Correlation measures the strength of a l

Question 9

A regression analysis of company profits and the amount of money the company spent on
Advertising found r2 = 0.72 . Which of these is true?
I. This model can correctly predict the profit for 72% of companies.
II. On average, about 72% of a company's profit results from advertising.
III. On average, companies spend about 72% of their profits on advertising.

Accepted Answer

A)  II only 
B)  I and III 
C)  none of these 
D)  III only 
E)  I only 
A)  II only 
B)  I and III 
C)  none of these 
D)  III only 
E)  I only

Question 10

What is the probability that exactly 2 of the first 20 blood donors have Type B blood?

Accepted Answer

\[P ( \text { exactly } 2 \tex

Question 11

In ANOVA, the Bonferroni method is used to...

Accepted Answer

A)  adjust for unequal variances between the treatment groups. 
B)  adjust for multiple comparisons between pairs of treatment groups. 
C)  none of these 
D)  adjust for small sample sizes within the treatment groups. 
E)  adjust for non-Normal data within the treatment groups. 
A)  adjust for unequal variances between the treatment groups. 
B)  adjust for multiple comparisons between pairs of treatment groups. 
C)  none of these 
D)  adjust for small sample sizes within the treatment groups. 
E)  adjust for non-Normal data within the treatment groups.

Question 12

SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
Solve the problem.
-One of the reasons that the Monitoring the Future (MTF) project was started was "to study
changes in the beliefs, attitudes, and behavior of young people in the United States." Data
are collected from 8th, 10th, and 12th graders each year. To get a representative nationwide
sample, surveys are given to a randomly selected group of students. In Spring 2004,
students were asked about alcohol, illegal drug, and cigarette use. Describe the W's, if the
information is given. If the information is not given, state that it is not specified.
• Who:
• What:
• When:
• Where:
• How:
• Why:

Accepted Answer

• Who: 8th, 10th, and 12th graders
• Wha

Question 13

Height and weight Suppose that both height and weight of adult men can be described
with Normal models, and that the correlation between these variables is 0.65. If a man's
height places him at the 60th percentile, at what percentile would you expect his weight to
be?

Accepted Answer

@#LAT-DLM&
height at 60th percentile: @#LAT-DLM&
R

Question 14

Find the following:
a. What percent of the young girls reported that they drink milk?
b. What percent of the young girls were in the 1989-1991 survey?
c. What percent of the young girls who reported that they drink milk were in the 1989-1991
survey?
d. What percent of the young girls in 1989-1991 reported they drink milk?

Accepted Answer

a. 56.9%
b

Question 15

What is the probability that the fisherman will get 5 nibbles on his line.

Accepted Answer

\[P ( x = 5 ) = \left( \begin{

Question 16

Bone Builder Researchers believe that a new drug called Bone Builder will help bones heal
after children have broken or fractured a bone. The researchers believe that Bone Builder
will work differently on bone breaks than on bone fractures, because of differences in
initial bone condition. Bone Builder will be used in conjunction with traditional casts. To
test the impact of Bone Builder on bone healing, the researchers recruit 18 children with
bone breaks and 30 children with bone fractures. Design an appropriate experiment to
determine if Bone Builder will help bones heal.

Accepted Answer

@#IMG-DLM& Blocking is employed since breaks and f

Question 17

If a data point is influential it…

Accepted Answer

A)  is guaranteed to be extreme in the horizontal direction. 
B)  has a small residual. 
C)  none of these 
D)  is guaranteed to be extreme in the vertical direction. 
E)  will change the slope of the regression equation. 
A)  is guaranteed to be extreme in the horizontal direction. 
B)  has a small residual. 
C)  none of these 
D)  is guaranteed to be extreme in the vertical direction. 
E)  will change the slope of the regression equation.

Question 18

The model $$\sqrt { \hat { \text { distance } }  } = 3.30 + 0.235 ( \text { speed } )$$ ) can be used to predict the stopping distance (in feet) for a
Car traveling at a specific speed (in mph). According to this model, about how much distance will a
Car going 65 mph need to stop?

Accepted Answer

A)  27.0 feet 
B)  18.6 feet 
C)  729.0 feet 
D)  4.3 feet 
E)  345.0 feet 
A)  27.0 feet 
B)  18.6 feet 
C)  729.0 feet 
D)  4.3 feet 
E)  345.0 feet

Question 19

Two variables that are actually not related to each other may nonetheless have a very high
Correlation because they both result from some other, possibly hidden, factor. This is an example of

Accepted Answer

A)  a lurking variable. 
B)  an outlier. 
C)  leverage. 
D)  extrapolation. 
E)  regression. 
A)  a lurking variable. 
B)  an outlier. 
C)  leverage. 
D)  extrapolation. 
E)  regression.

Question 20

The best estimate of the standard deviation of the mens' weights displayed in this dotplot is

Accepted Answer

A)  40 
B)  25 
C)  15 
D)  35 
E)  10 
A)  40 
B)  25 
C)  15 
D)  35 
E)  10

Would it be better for customers for a year to have a negative residual or a positive residual from this model? Explain.

Which is true about a 99% confidence interval based on a given sample? I. The interval contains 99% of the population. II. Results from 99% of all samples will lie in this interval. III. The interval is wider than a 95% confidence interval would be.

Which is true about a 95% confidence interval based on a given sample? I. The interval contains 95% of the population. II. Results from 95% of all samples will lie in the interval. III. The interval is narrower than a 98% confidence interval would be.

Describe how you will use a random number table to conduct this simulation.

What is the probability that none of the first three customers gets more than a 30% discount?

Which statement correctly compares t-distributions to the normal distribution? I. t distributions are also mound shaped and symmetric. II. t distributions have less spread than the normal distribution. III. As degrees of freedom increase, the variance of t distributions becomes smaller.

After conducting a survey of his students, a professor reported that "There appears to be a strong correlation between grade point average and whether or not a student works." Comment on this observation.

What is the probability that exactly 2 of the first 20 blood donors have Type B blood?

In ANOVA, the Bonferroni method is used to...

Height and weight Suppose that both height and weight of adult men can be described with Normal models, and that the correlation between these variables is 0.65. If a man's height places him at the 60th percentile, at what percentile would you expect his weight to be?

What is the probability that the fisherman will get 5 nibbles on his line.

If a data point is influential it…

The model $\sqrt { \hat { \text { distance } } } = 3.30 + 0.235 ( \text { speed } )$ ) can be used to predict the stopping distance (in feet) for a Car traveling at a specific speed (in mph). According to this model, about how much distance will a Car going 65 mph need to stop?

Two variables that are actually not related to each other may nonetheless have a very high Correlation because they both result from some other, possibly hidden, factor. This is an example of

The best estimate of the standard deviation of the mens' weights displayed in this dotplot is

Exploring and Understanding Data

Exploring Relationships Between Variables

Gathering Data

Randomness and Probability

From the Data at Hand to the World at Large

Accessing Associations Between Variables

Inference When Variables Are Related

Filters

Exam 8: Regression, Associations, and Predictive Modeling

Would it be better for customers for a year to have a negative residual or a positive residual from this model? Explain.

Which is true about a 99% confidence interval based on a given sample? I. The interval contains 99% of the population. II. Results from 99% of all samples will lie in this interval. III. The interval is wider than a 95% confidence interval would be.

Which is true about a 95% confidence interval based on a given sample? I. The interval contains 95% of the population. II. Results from 95% of all samples will lie in the interval. III. The interval is narrower than a 98% confidence interval would be.

Describe how you will use a random number table to conduct this simulation.

What is the probability that none of the first three customers gets more than a 30% discount?

Which statement correctly compares t-distributions to the normal distribution? I. t distributions are also mound shaped and symmetric. II. t distributions have less spread than the normal distribution. III. As degrees of freedom increase, the variance of t distributions becomes smaller.

After conducting a survey of his students, a professor reported that "There appears to be a strong correlation between grade point average and whether or not a student works." Comment on this observation.

What is the probability that exactly 2 of the first 20 blood donors have Type B blood?

In ANOVA, the Bonferroni method is used to...

Height and weight Suppose that both height and weight of adult men can be described with Normal models, and that the correlation between these variables is 0.65. If a man's height places him at the 60th percentile, at what percentile would you expect his weight to be?

What is the probability that the fisherman will get 5 nibbles on his line.

If a data point is influential it…

Two variables that are actually not related to each other may nonetheless have a very high Correlation because they both result from some other, possibly hidden, factor. This is an example of

The best estimate of the standard deviation of the mens' weights displayed in this dotplot is

Exploring and Understanding Data

Exploring Relationships Between Variables

Gathering Data

Randomness and Probability

From the Data at Hand to the World at Large

Accessing Associations Between Variables

Inference When Variables Are Related

Filters