MA 2113
Homework #1
Table 1. Count of tree types on a selected study site on Noxubee National Wildlife Refuge.
Species
Total
Yellow Poplar
5
Winged Elm
11
Tupelo
50
Red Oak
11
Shagbark Hickory
17
Sweetgum
47
Red Maple
26
Post Oak
5
Persimmon
2
Rel Freq
%
1. What type of data is this? Quantitative or Qualitative
2. Calculate the relative frequency and percentage of each type.
3. Construct a bar graph of the relative frequency of types of trees.
Table 2. Heights of trees (feet) for a selected study site on Noxubee National Wildlife Refuge.
70
105
73
86
22
31
48
27
40
62
45
45
62
35
75
18
25
32
37
34
25
28
18
20
37
50
40
72
25
40
45
70
35
40
25
25
45
45
70
60
45
70
45
37
27
60
50
4. What type of data is this? Quantitative or Qualitative
5. Calculate relative frequency of heights by class. You determine the class intervals, so you do not have
to use all rows or you can add some.
6. Construct a histogram of relative frequency of scores by class.
Class
Freq
Rel Freq
%
MA 2113
Homework #2
Be sure to show all tables and calculations!
Table 1. Infant mortality rates (IMR = deaths of children <1 year old per 1,000 births) by nation
in 2003.
COUNTRY
IMR
Argentina
15.5
Australia
2.8
Canada
4.2
Chile
7.3
China
25.7
Colombia
20.5
Ecuador
24.7
France
2.4
Germany
3.5
Italy
4.2
Japan
2.6
Malaysia
17
Mexico
21.8
Netherlands
3.2
North Korea
25
Philippines
23
Poland
8.3
Romania
26.1
Russia
16.7
Saudi Arabia
12.2
South Korea
6.6
Spain
2.5
Sri Lanka
Taiwan
14.5
4.7
Thailand
21.1
Ukraine
18.9
United Kingdom
4.6
United States
4.8
Venezuela
23.1
Vietnam
28.8
1. What is the mean and standard deviation for IMR for these countries?
2. What is the median and Five-number Summary (quartiles) for IMR for these countries?
MA 2113
Homework #3
1. Determine outliers, if any, and construct a boxplot of the following data.
Table 1. Number of games played by Wayne Gretzky (pro hockey player) in each of his 20 seasons.
77
78
71
46
78
78
76
78
78
77
72
80
78
62
43
80
72
76
79
68
2. For the following equations provide:
a) y-intercept and slope
b) Construct a graph of the equation (plot at least 2 points other than the y-intercept)
y = 3 + 2x
y = 6 – 5x
y = 0.5x – 1
y=x–3
ST 2113
Homework #4
1. Calculate a regression equation using the (x, y) data below (8 points). We are interested to see if a
student’s grade on Exam 1 (x) has any relationship to final average (y) for a course.
To check if you have done your work correctly, this should be your answer:
ŷ = 50.4 + 0.49 x
Of course, show all your work.
Exam1 (x ) Final (y )
104
97.6
51
90.0
83
96.0
73
81.0
71
81.7
58
69.8
64
77.9
85
98.2
41
66.4
2. Graph a scatterplot of the data along with the regression line from the regression equation (2 points).
MA 2113
Homework #5
1. Compute the coefficient of determination for the regression equation calculated using the data below.
Table 1. Age, x, in years and price, y, in dollars (divided by 100) from a random sample of 12 Honda
Accords listed for sale on AutoTrader.com within 100 miles of Meridian, MS.
Age (x ) Price (y )
14
56.0
4
99.8
10
110.0
3
139.8
6
160.0
2
170.0
3
175.0
5
172.4
16
48.0
19
50.0
11
91.9
10
92.8
Hint: You will need to first calculate the regression equation as you did in Homework #4. You should get
b1 = – 7.67 and b0 = 179.63. For the regression coefficient below, you should get r2 = 0.7889 or 78.9%.
Price (y )
56.0
99.8
110.0
139.8
160.0
170.0
175.0
172.4
48.0
50.0
91.9
92.8
MA 2113
Homework #6
1. Compute the Pearson correlation coefficient, r, for the data below.
Table 1. Data from homework #5, age of used Honda Accords (x) and price (y).
x
y
14
56.0
4
99.8
10
110.0
3
139.8
6
160.0
2
170.0
3
175.0
5
172.4
16
48.0
19
50.0
11
91.9
10
92.8
To check your final answer, r = – 0.887 X 100 = 88.7%