Descriptive Statistics
1. The
table below presents data for a sample of people who completed a religious
survey.
|
Age |
Gender |
Denomination |
Church Attendance |
|
56 |
1 |
7 |
4 |
|
46 |
2 |
6 |
5 |
|
49 |
2 |
6 |
5 |
|
49 |
1 |
1 |
5 |
|
27 |
2 |
9 |
5 |
|
51 |
1 |
4 |
2 |
|
47 |
2 |
2 |
3 |
|
67 |
1 |
5 |
4 |
|
49 |
2 |
2 |
6 |
|
33 |
1 |
12 |
6 |
|
55 |
2 |
9 |
5 |
|
40 |
1 |
7 |
5 |
|
62 |
1 |
8 |
6 |
|
47 |
2 |
6 |
3 |
|
56 |
2 |
9 |
5 |
|
22 |
1 |
10 |
2 |
|
50 |
2 |
4 |
5 |
|
51 |
1 |
10 |
6 |
|
50 |
1 |
7 |
6 |
|
43 |
1 |
10 |
3 |
In
this table, the numbers in the gender, denomination, and church attendance columns
represent the following.
Gender
1.
Male
2.
Female
Denomination
1.
Episcopal
2.
Lutheran
3.
Methodist
4.
Presbyterian
5.
Other mainline Protestant
6.
Baptist
7.
Other Evangelical Protestant
8.
Pentecostal
9.
Charismatic
10.
Non-denominational
11.
Catholic
12.
Other
Church Attendance
1.
less than once a month
2.
once a month
3.
a few times a month
4.
once a week
5.
twice a week
6.
three or more times a week
a.
What is the mean age of this
sample? What is the standard deviation?
b.
Create a frequency
distribution table for denomination.
- What is the percentage of people who identify
themselves as Baptist in this sample?
d.
What is the mode of church
attendance?
results of a recent survey indicate that the average new car costs $23,000,
with a standard deviation of $3,500. The price of cars is normally distributed.
a. What
is a Z score for a car with a price of $ 33,000?
b. What is a Z score for a car with a price of$30,000?
c. At
what percentile rank is a car that sold for $30,000?
1. In
one elementary school, 200 students are tested on the subject of Math and
English. The table below shows the mean and standard deviation for each
subject.
|
Mean |
SD |
|
|
Math |
67 |
9.58 |
|
English |
78 |
12.45 |
One student’s Math score was 70 and
the same individual’s English score was 84. On which exam did the student do
better?
you administered an anxiety test to a large sample of people and obtained normally
distributed scores with a mean of 45 and standard deviation of 4. Do not use
web-calculator to answer the following questions. Instead, you need to use the
Z distribution table in Appendix A in Jackson’s book.
a. If
Andrew scored 45 on this test. What is his Z score?
b. If
Anna scored 30 on this test. What is her Z score?
c. If
Bill’s Z score was 1.5, what is his real score on this test?
d. There
are 200 students in a sample. How many of these students will have scores that
fall under the score of 41?
1. The
table below shows Psychology exam scores, Statistics Exam scores, and IQ scores
for a random sample of students. What can you observe in the relationship
between IQ and psychology, psychology and statistics, and IQ and statistics?
Using a web-calculator, obtain the Pearson’s r and coefficient of determination for the following relationships.
a. Between
the IQ and psychology scores
b. Between
the IQ and statistics scores
c. Between
the psychology scores and statistics scores.
|
Student number |
IQ |
Psychology |
Statistics |
|
101 |
142 |
49 |
49 |
|
102 |
100 |
30 |
32 |
|
103 |
103 |
36 |
38 |
|
104 |
121 |
44 |
41 |
|
105 |
120 |
35 |
42 |
|
106 |
115 |
47 |
43 |
|
107 |
101 |
37 |
35 |
|
108 |
109 |
45 |
47 |
|
109 |
111 |
30 |
43 |
|
110 |
115 |
49 |
46 |
1. In
a study on caffeine and stress, college students indicated how many cups of
coffee they drink per day and their current stress level on a scale of 1 to 10.
The table shows the survey results. Using
a web-calculator, obtain the appropriate correlation coefficients.
|
Number of cups of coffee |
Stress level |
|
3 |
5 |
|
2 |
3 |
|
4 |
3 |
|
6 |
9 |
|
5 |
4 |
|
1 |
2 |
|
7 |
10 |
|
3 |
5 |
