Could you please provide me with some tutoring by answering the
following question? All information enclosed is ficticous.
Thanks in advance!
1.
5. The city council of Pine Bluffs is considering increasing the
number of police in an effort to
reduce crime. Before making a final decision, the council asks the
Chief of Police to survey
other cities of similar size to determine the relationship between the
number of police and
the number of crimes reported. The Chief gathered the following sample information.
City Police Number of Crimes City Police Number of Crimes
Oxford 15 17 Holgate 17 7
Starksville 17 13 Carey 12 21
Danville 25 5 Whistler 11 19
Athens 27 7 Woodville 22 6
a. If we want to estimate crimes based on the number of police, which
variable is the
dependent variable and which is the independent variable?
b. Draw a scatter diagram.
c. Determine the coefficient of correlation.
d. Determine the coefficient of determination.
2.
6. The owner of Maumee Motors wants to study the relationship between
the age of a car and
its selling price. Listed below is a random sample of 12 used cars
sold at Maumee Motors
during the last year.
Car Age (years) Selling Price ($000) Car Age (years) Selling Price ($000)
1 9 8.1 7 8 7.6
2 7 6.0 8 11 8.0
3 11 3.6 9 10 8.0
4 12 4.0 10 12 6.0
5 8 5.0 11 6 8.6
6 7 10.0 12 6 8.0
a. If we want to estimate selling price based on the age of the car,
which variable is the
dependent variable and which is the independent variable?
b. Draw a scatter diagram.
c. Determine the coefficient of correlation.
d. Determine the coefficient of determination.
e. Interpret these statistical measures. Does it surprise you that the
relationship is inverse?
3.
15. A recent article in Business Week listed the ?Best Small
Companies.? We are interested
in the current results of the companies? sales and earnings. A random
sample of 12 companies
was selected and the sales and earnings, in millions of dollars, are
reported below.The following figures are all in millions.
Company Sales Earnings Company Sales Earnings
Papa John? s Interna tional $89.2 $4.9 Checkmate Electronics $17.5 $ 2.6
Applied Innovation 18.6 4.4 Royal Grip 11.9 1.7
Integracare 18.2 1.3 M-Wave 19.6 3.5
Wall Data 71.7 8.0 Serving-N-Slide 51.2 8.2
Davidson Associates 58.6 6.6 Daig 28.6 6.0
Chico?s Fas 46.8 4.1 Cobra Golf 69.2 12.8
Let sales be the independent variable and earnings be the dependent variable.
a. Draw a scatter diagram.
b. Compute the coefficient of correlation.
c. Compute the coefficient of determination.
d. Interpret your findings in parts b and c.
e. Determine the regression equation.
f. For a small company with $50.0 million in sales, estimate the earnings.
4.
16. We are studying mutual bond funds for the purpose of investing in
several funds. For this
particular study, we want to focus on the assets of a fund and its
five-year performance.
The question is: Can the five-year rate of return be estimated based
on the assets of the
fund? Nine mutual funds were selected at random, and their assets and
rates of return are
shown below. Assets are in millions.
Fund Assets Return(%) Fund Assets Return(%)
AARP High Quality Bond $622.2 10.8 MFS Bond A $494.5 11.6
Babson Bond L 160.4 11.3 Nichols Income 158.3 9.5
Compass Capital Fixed Income 275.7 11.4 T. Raive Price
Short-term 681.0 8.2
Galaxy Bond Retail 433.2 9.1 Thompson
Income B 241.3 6.8
Keystone Custodian B-1 437.9 9.2
a. Draw a scatter diagram.
b. Compute the coefficient of correlation.
c. Compute the coefficient of determination.
d. Write a brief report of your findings for parts b and c.
e. Determine the regression equation. Use assets as the independent variable.
f. For a fund with $400.0 million in sales, determine the five-year
rate of return (in percent).
5.
13. The Bradford Electric Illuminating Company is studying the
relationship between kilowatthours
(thousands) used and the number of rooms in a private single-family residence.
A random sample of 10 homes yielded the following.
Number of Kilowatt-Hours Number of Kilowatt-Hours
Rooms (thousands) Rooms (thousands)
12 9 8 6
9 7 10 8
14 10 10 10
6 5 5 4
10 8 7 7
a. Determine the .95 confidence interval, in thousands of
kilowatt-hours, for the mean of all
six-room homes.
b. Determine the .95 prediction interval, in thousands of
kilowatt-hours, for a particular sixroom
home |
