Name:___________________________________
Homework #2 (Day)
Due: Thu., Jun. 9, 11 am
Read the directions carefully, and answer all parts of each question. Write neatly; if I can’t read it, it will
be counted wrong. You may work in groups, but you must submit your own solution. Any submissions
that are word-for-word identical will receive a score of 0. Use this sheet as a cover page or lose five
points. No late homework will be accepted under any circumstances.
1. For this problem, use the dataset “Forte.xlsx” located on the webpage.
a. Construct a frequency distribution.
b. Construct a relative frequency distribution.
c. Construct a cumulative relative frequency distribution.
Value
0
1
2
3
Frequency Relative Fr Cum. Freq
7
0.4375
0.4375
6
0.375
0.8125
1
0.0625
0.875
2
0.125
1
2. For this problem, refer to the table at the bottom of the page.
a. What is the joint frequency of incoming freshmen who are Accounting majors?
11
b. What is the marginal frequency of current sophomores?
4 + 13 + 9 = 26
c. What is the marginal frequency of Business majors?
17 + 15 + 13 = 45
d. How many students are either current freshman or Economics majors?
(2 + 15 + 20) + (3 + 2 + 4) – 2 = (37 + 9) – 2 = 44
3. For this problem, use the dataset “Forte.xlsx” located on the webpage.
a. Calculate the mean.
0.875
b. Calculate the median.
1
c. Describe the shape of the distribution.
Probably symmetric. The mean and median do differ, but it’s a pretty small difference.
d. Calculate the mode.
0 occurs most often, so 0 is the mode.
e. What percentile is “2 touchdowns” located in?
2 occupies the 14th position. 14 =
𝑝
(16), 𝑝
100
f.
Calculate the range.
3–0=3
g. Calculate the interquartile range.
25
(16), 𝑖 = 4, 𝑥 = 0
100
75
= 100 (16), 𝑖 = 12, 𝑥 =
First quartile: 𝑖 =
Third quartile: 𝑖
1
“All the Constitution guarantees is the pursuit of happiness.
You have to catch up with it by yourself.”
-Benjamin Franklin
= 87.5𝑡ℎ 𝑝𝑒𝑟𝑐𝑒𝑛𝑡𝑖𝑙𝑒
Name:___________________________________
Homework #2 (Day)
Due: Thu., Jun. 9, 11 am
IQ Range = 1 – 0 = 0
h. Calculate the variance.
Sample variance = 1.05, Population variance = 0.98.
Since I didn’t distinguish, I’ll accept either.
i. Calculate the coefficient of variation.
You’ll need the standard deviation which is the square root of the variance.
Sample StDev = 1.02, Population StDev = 0.99
1.02
0.99
So we have: 𝐶𝑉𝑠𝑎𝑚𝑝𝑙𝑒 = 0.875 (100%) = 116.5%, 𝐶𝑉𝑃𝑜𝑝 = 0.875 (100%) = 113.1%
j.
Calculate the Z-value for “2 touchdowns”.
2−0.875
= 1.10
1.02
2−0.875
Population: 𝑍𝑥=2 = 0.99 = 1.13
Sample: 𝑍𝑥=2 =
Table for Problem 2
Incoming Freshman
Current Freshman
Current Sophomore
Economics
3
2
4
Business
17
15
13
“All the Constitution guarantees is the pursuit of happiness.
You have to catch up with it by yourself.”
-Benjamin Franklin
Accounting
11
20
9