Question 1

State your conclusion.

Accepted Answer

Trial 1 required 8 families, Trial 2 req

Question 2

The five-number summary for the fuel economy (in miles per gallon) of year 2011 midsize
cars is: $$\begin{array} { | c | c | c | c | c | } 
\hline \text { Min } & \text { Q1 } & \text { Median } & \text { Q3 } & \text { Max } \
\hline 13 & 21 & 23 & 26 & 50 \
\hline
\end{array}$$ 
a. Would you expect the mean gas mileage of all midsize cars to be higher or lower than
the median? Explain.
b. One model of Volkswagon gets 34 mpg, one model of Toyota gets 28 mpg, and one
model of Bentley gets 13 mpg. Are any of these cars outliers (according to the original
statistics above)? Explain.

Accepted Answer

a. Probably higher. The data appear to b

Question 3

Write the equation of the least-squares regression line for the transformed data. Draw the
regression line on the scatterplot in question 2.

Accepted Answer

The answer of Write the equation of the least-squares regression...

Question 4

Insurance company records indicate that 12% of all teenage drivers have been ticketed for speeding
And 9% for going through a red light. If 4% have been ticketed for both, what is the probability that
A teenage driver has been issued a ticket for speeding but not for running a red light?

Accepted Answer

A)  12% 
B)  17% 
C)  13% 
D)  3% 
E)  8% 
A)  12% 
B)  17% 
C)  13% 
D)  3% 
E)  8%

Question 5

Describe to management an advantage and disadvantage of using a 1% alpha level of
significance instead.

Accepted Answer

Advantage: management would be less like

Question 6

A truck company wants on-time delivery for 98% of the parts they order from a metal Manufacturing plant. They have been ordering from Hudson Manufacturing but will switch to a New, cheaper manufacturer (Steel-R-Us) unless there is evidence that this new manufacturer Cannot meet the 98% on-time goal. As a test the truck company purchases a random sample of Metal parts from Steel-R-Us, and then determines if these parts were delivered on-time. Which Hypothesis should they test?

Accepted Answer

A)  $\mathrm { H } _ { 0 } : p = 0.98$
$\mathrm { H } _ { \mathrm { A } } : p  0.98$ 
C)  $\mathrm { H } _ { 0 } : p = 0.98$
$\mathrm { H } _ { \mathrm { A } } : p \neq 0.98$ 
D)  $\mathrm { H } _ { 0 } : p = 0.98$
$\mathrm { H } _ { \mathrm { A } } : p > 0.98$ 
E)  $\mathrm { H } _ { 0 } : p > 0.98$
$\mathrm { H } _ { \mathrm { A } } : p = 0.98$ 
A)  $\mathrm { H } _ { 0 } : p = 0.98$
$\mathrm { H } _ { \mathrm { A } } : p  0.98$ 
C)  $\mathrm { H } _ { 0 } : p = 0.98$
$\mathrm { H } _ { \mathrm { A } } : p \neq 0.98$ 
D)  $\mathrm { H } _ { 0 } : p = 0.98$
$\mathrm { H } _ { \mathrm { A } } : p > 0.98$ 
E)  $\mathrm { H } _ { 0 } : p > 0.98$
$\mathrm { H } _ { \mathrm { A } } : p = 0.98$

Question 7

Which statement about residuals plots is true?
I. A curved pattern indicates nonlinear association between the variables.
II. A pattern of increasing spread indicates the predicted values become less reliable as the
Explanatory variable increases.
III. Randomness in the residuals indicates the model will predict accurately.

Accepted Answer

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

Question 8

In this context describe a Type I error and the impact such an error would have on the
company.

Accepted Answer

A Type I error would be deciding the per

Question 9

Egg weights The weights of hens' eggs are normally distributed with a mean of 56 grams
and a standard deviation of 4.8 grams. What is the probability that a dozen randomly
selected eggs weighs over 690 grams?

Accepted Answer

The answer of Egg weights The weights of hens' eggs...

Question 10

A plot of the residuals versus the fitted values for record-breaking times of female
marathon runners for the years 1998 - 2003 is:   
Based on this residuals plot, does it seem reasonable to use linear regression for this
model? Explain.

Accepted Answer

Since we see a clear pattern i

Question 11

One thousand students from a local university were sampled to gather information such as
gender, high school GPA, college GPA, and total SAT scores. The results were used to
create histograms displaying high school grade point averages (GPAs) for both males and
females. Compare the grade distribution of males and females.

Accepted Answer

The distributions of high school GPA for

Question 12

What is the probability that there is at least one gold winner among the first six customers?

Accepted Answer

The answer of What is the probability that there is...

Question 13

A P-value indicates

Accepted Answer

A)  the probability the null is true given the observed statistic. 
B)  the probability that the alternative hypothesis is true. 
C)  the probability of the observed statistic given that the null hypothesis is true. 
D)  the probability of the observed statistic given that the alternative hypothesis is true. 
E)  the probability that the null hypothesis is true. 
A)  the probability the null is true given the observed statistic. 
B)  the probability that the alternative hypothesis is true. 
C)  the probability of the observed statistic given that the null hypothesis is true. 
D)  the probability of the observed statistic given that the alternative hypothesis is true. 
E)  the probability that the null hypothesis is true.

Question 14

A regression equation is found that predicts the increased cost of a home owner's electricity bill given the number of holiday lights they put on the outside of their house. The equation is dollars = $2.5 + 0.02$ (light). If a house has 400 lights and a $\$ 15$ increase in their electricity cost, find their residual.

Accepted Answer

A)  $- \$ 15$ 
B)  $- \$ 5$ 
C)  $\$ 15$ 
D)  $\$ 20$ 
E)  $\$ 5$ 
A)  $- \$ 15$ 
B)  $- \$ 5$ 
C)  $\$ 15$ 
D)  $\$ 20$ 
E)  $\$ 5$

Question 15

If these data were collected in California, would you feel confident in using this equation to
make predictions about Florida orange groves also? Explain.

Accepted Answer

No. It would be a dangerous as

Question 16

Do you think a model could accurately predict the number of calories in a serving of cereal
that has 22 grams of fiber? Explain.

Accepted Answer

This data contains information about cer

Question 17

Strange dice A game is played with 2 strange dice.
• The six faces of Die A show a 1 and five 3's.
• Die B has four 2's and two 6's.
a. Create a probability model for the total you get when you roll both dice.
b. Find the mean of the total.
c. Find the standard deviation of the total.

Accepted Answer

\[\begin{array}{l}
\begin{array} { | l |

Question 18

A silly psychology student gathers data on the shoe size of 30 of his classmates and their GPA's.
The correlation coefficient between these two variables is most likely to be

Accepted Answer

A)  near 0 
B)  near $- 0.6$ 
C)  exactly $+ 1.0$ 
D)  exactly $- 1.0$ 
E)  near $+ 0.6$ 
A)  near 0 
B)  near $- 0.6$ 
C)  exactly $+ 1.0$ 
D)  exactly $- 1.0$ 
E)  near $+ 0.6$

Question 19

Describe an advantage to random assignment of treatment.

Accepted Answer

Randomization will equalize va

Question 20

All students in a physical education class completed a basketball free-throw shooting
event and the highest number of shots made was 32. The next day a student who had just
transferred into the school completed the event, making 35 shots. Indicate whether adding
the new student's score to the rest of the data made each of these summary statistics
increase, decrease, or stay about the same:
a. mean
b. median
c. range
d. IQR
e. standard deviation

Accepted Answer

a. increase
b. stay

State your conclusion.

Write the equation of the least-squares regression line for the transformed data. Draw the regression line on the scatterplot in question 2.

Insurance company records indicate that 12% of all teenage drivers have been ticketed for speeding And 9% for going through a red light. If 4% have been ticketed for both, what is the probability that A teenage driver has been issued a ticket for speeding but not for running a red light?

Describe to management an advantage and disadvantage of using a 1% alpha level of significance instead.

In this context describe a Type I error and the impact such an error would have on the company.

Egg weights The weights of hens' eggs are normally distributed with a mean of 56 grams and a standard deviation of 4.8 grams. What is the probability that a dozen randomly selected eggs weighs over 690 grams?

A plot of the residuals versus the fitted values for record-breaking times of female marathon runners for the years 1998 - 2003 is: Based on this residuals plot, does it seem reasonable to use linear regression for this model? Explain.

What is the probability that there is at least one gold winner among the first six customers?

A P-value indicates

If these data were collected in California, would you feel confident in using this equation to make predictions about Florida orange groves also? Explain.

Do you think a model could accurately predict the number of calories in a serving of cereal that has 22 grams of fiber? Explain.

Strange dice A game is played with 2 strange dice. • The six faces of Die A show a 1 and five 3's. • Die B has four 2's and two 6's. a. Create a probability model for the total you get when you roll both dice. b. Find the mean of the total. c. Find the standard deviation of the total.

A silly psychology student gathers data on the shoe size of 30 of his classmates and their GPA's. The correlation coefficient between these two variables is most likely to be

Describe an advantage to random assignment of treatment.

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

State your conclusion.

Write the equation of the least-squares regression line for the transformed data. Draw the regression line on the scatterplot in question 2.

Insurance company records indicate that 12% of all teenage drivers have been ticketed for speeding And 9% for going through a red light. If 4% have been ticketed for both, what is the probability that A teenage driver has been issued a ticket for speeding but not for running a red light?

Describe to management an advantage and disadvantage of using a 1% alpha level of significance instead.

In this context describe a Type I error and the impact such an error would have on the company.

Egg weights The weights of hens' eggs are normally distributed with a mean of 56 grams and a standard deviation of 4.8 grams. What is the probability that a dozen randomly selected eggs weighs over 690 grams?

A plot of the residuals versus the fitted values for record-breaking times of female marathon runners for the years 1998 - 2003 is: Based on this residuals plot, does it seem reasonable to use linear regression for this model? Explain.

What is the probability that there is at least one gold winner among the first six customers?

A P-value indicates

If these data were collected in California, would you feel confident in using this equation to make predictions about Florida orange groves also? Explain.

Do you think a model could accurately predict the number of calories in a serving of cereal that has 22 grams of fiber? Explain.

Strange dice A game is played with 2 strange dice. • The six faces of Die A show a 1 and five 3's. • Die B has four 2's and two 6's. a. Create a probability model for the total you get when you roll both dice. b. Find the mean of the total. c. Find the standard deviation of the total.

A silly psychology student gathers data on the shoe size of 30 of his classmates and their GPA's. The correlation coefficient between these two variables is most likely to be

Describe an advantage to random assignment of treatment.

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