WEEK 1 â
EXERCISES
Enter your answers in the spaces
provided. Save the file using your last name as the beginning of the file name
(e.g., ruf_week1_exercises) and submit via âAssignments.â When appropriate, show
your work. You can do the work by hand, scan/take a digital picture, and
attach that file with your work.
1. Find
the mean, median, and mode for the following sample of scores:
2,3,3,1,2,5,2,3,4,2
2. For
the data in the following sample:
8,
1, 5, 1, 5
a.
Find the mean and the standard deviation
b.
Now change the score of X=8
to X=18, and find the new mean and
standard deviation.
c.
Describe how one extreme score influences the mean and the standard
deviation
3. A recent study reports that older
adults who got regular physical exercise (as measured by a pedometer)
experienced fewer symptoms of depression, even when tested 2 years later.
Following are hypothetical data similar to the results obtained in this study.
a.
Calculate the mean and standard
deviation for each group of scores
b. Based on the statistics from part a,
does it appear to be a difference between the two groups?
Regular
Exercise
No
regular exercise
1
5
3
4
4
6
3
3
5
5
2
7
3
6
4
6
4. A
survey of 1,250 people asked how often they used the Internet. 96 responded
that they never use it; 214 said they rarely use it; 572 said they use it
occasionally, and 368 said they used it all the time.
a.
Fill in the table below with the
frequencies and percentages for each category.
Remember to create a table whose
categories are arranged logically.
INTERNET USAGE
f
%
N =
b. What
does N equal? ________________
c. What
is the level of measurement? ____________________________
5. Below
is a frequency distribution for majors for a Western university.
a. Fill in the table below with the
missing information.
LABEL (x)
f
%
Humanities
243
Social Sciences
521
Natural Sciences
349
Education
236
Nursing
169
Business
448
Total (N)
b. What
does N equal? ________________
c.
What is the level of measurement?
____________________________