Work hard to make certain that the results you have are accurate based on class material. Use T- table and Z-table when needed. Feel free to consult and cite the notes and previous assignments in preparing this exam. Please show all of your working out so I am able to see your path to your answer. Mistakes will be penalized however showing your working out will allow me to deduct fewer points. If no working out is shown, I will be forced to deduct full points for mistakes. ** . Z table and T table are attached. Please read carefully ! When appropriate and possible, express your answer in the same units as the variable. For example, if the question asks for the mean years of formal education and you have calculated the mean to be 18.44, your answer should be expressed as “ 18.44 years of formal education .” Equations to Use Median Position = N+1/2 The Median Value is the midpoint between the scores. Mean = å x / N Standard Deviation = Z score = x – mean / standard deviation CI = For samples sizes ≥ 100, the formula for the CI is: CI = ­ (the sample mean) + & - Z( s / √N – 1) CI = For samples sizes < 100, the formula for the CI is: CI = ­ (the sample mean) + & - T( s / √N – 1) Please answer the following questions: You are interested in the effects of release with aftercare for a small number of drug offenders. The number of additional months without drug use for a sample of 6 offenders is recorded. The data on the six (6) subjects are as follows: 2 8 5 2 8 2 What are the median position and the median value ? (3 points) What is the mean? ( 2 points) What is the most frequently occurring score in this distribution of scores - mode? (2 point) 2. Computation of a mode is most appropriate when a variable is measured at which level? (2 points) A. interval-ratio B. ordinal C. nominal D. discrete Answer: ________________________ 3. Assume that the distribution of a college entrance exam is normal with a mean of 500 and a standard deviation of 100 . For each score below, find the equivalent Z score, the percentage of the area above the score, and the percentage of the area below the score. ( 5 each = total 10 points) Score                                   Z score                  % Area Above             % Area Below a) 437 b) 526 4. The class intervals below represent ages of respondents. Which list is both exhaustive and mutually exclusive? (2 points) A. 119–120, 120–121, 121–122 B. 119–120, 121–122, 123–124 C. 119–121, 123–125, 127–129 D. 119–120, 122–123, 125–126 Answer: ______________________ 5. The parole board is alarmed by the low number of years actually spent in prison for those inmates sentences to 15-year sentences. To help them make parole recommendations they gather data on the number of years served for a small sample of 7 ( seven) p otential parolees. The number of years served for these seven parol.

1. Work hard to make certain that the results you have are accurate
based on class material.
Use T- table and Z-table when needed.
Feel free to consult and cite the notes and previous assignments
in preparing this exam.
Please show all of your working out so I am able to see your
path to your answer. Mistakes will be penalized however
showing your working out will allow me to deduct fewer points.
If no working out is shown, I will be forced to deduct full
points for mistakes.
**
.
Z table and T table are attached.
Please read carefully
!
When appropriate and possible, express your answer in the same
units as the variable.
For example, if the question asks for the mean years of formal
education and you have calculated the mean to be 18.44, your
answer should be expressed as “
18.44 years of formal education
.”

2. Equations to Use
Median Position = N+1/2
The
Median Value
is the midpoint between the scores.
Mean
=
å
x
/ N
Standard Deviation =
Z score =
x – mean / standard deviation

3. CI =
For samples sizes ≥ 100,
the formula for the
CI
is:
CI
= -
(the sample mean) + & - Z(
s / √N – 1)
CI =
For samples sizes < 100,
the formula for the
CI
is:
CI
= -
(the sample mean) + & - T(
s / √N – 1)

4. Please answer the following questions:
You are interested in the effects of release with aftercare for a
small number of drug offenders. The number of additional
months without drug use for a sample
of 6 offenders
is recorded. The data on the six (6) subjects are as follows:
2
8
5
2

5. 8
2
What are the
median position
and the
median value
?
(3 points)
What is the mean?
(
2 points)
What is the most frequently occurring score in this distribution
of scores - mode?
(2 point)
2. Computation of a mode is most appropriate when a variable is
measured at which level?
(2 points)
A. interval-ratio
B. ordinal
C. nominal
D. discrete
Answer: ________________________

6. 3.
Assume that the distribution of a college entrance exam is
normal with
a mean of 500 and a standard deviation of 100
.
For each score below, find the equivalent Z score, the
percentage of the area above the score, and the percentage of
the area below the score.
( 5 each = total 10 points)
Score Z score % Area
Above % Area Below
a) 437
b) 526
4. The class intervals below represent ages of respondents.
Which list is both exhaustive and mutually exclusive?
(2 points)
A. 119–120, 120–121, 121–122
B. 119–120, 121–122, 123–124
C. 119–121, 123–125, 127–129
D. 119–120, 122–123, 125–126
Answer: ______________________
5. The parole board is alarmed by the low number of years
actually spent in prison for those inmates sentences to 15-year
sentences. To help them make parole recommendations they
gather data on the number of years served for a small sample of
7 (

7. seven) p
otential parolees. The number of years served for these seven
parolees is as follows:
4
5
3
6
3
3
7
What is the
standard deviation
for this distribution?
(6 points)
6. A teacher gives the following assignment to
200
students: Check the local newspaper every morning for a week
and count how many times the word “prison” is mentioned on
the “local news” pages. At the end of the week, the students
report their totals.

8. The mean result is 40, with a standard deviation of 20.
The distribution of scores is normal.
(7 points)
Question: How many students would be expected
to count between 50 and 70 cases
? (
in other words, what proportion of cases fall between 50 and 70
cases – calculate the Z score).
7.
The researcher collapsed the variable income into three
categories:
1=Less than $25,000; 2=$25,000-50,000; 3= $50,000-75,000;
4=Greater than $75,000. What mistake did she make? (2 points)
The categories are not mutually exclusive
The categories and not exhaustive
The variable is interval-ratio and should not have been
collapsed
The score intervals are not realistic
Answer:______________________
8.
Tom wants to research the relationship between gender and
alcohol. He designs a survey questionnaire, administers it,

9. collects the data, enters the data into SPSS, and conducts
______________________ analysis.
(2 points)
primary
secondary
Answer: ________________
9.
A state department has a policy whereby it accepts as police
officers only those who score in the top 5 % of a qualifying
exam.
The mean of this test is 50.
Standard deviation is 10.
Would a person with a raw score of
85
be accepted?
(7 points)
10.
Assume you have administered a test to random sample of
N-sample=100 workers
at your company. The test is purported to have a population
standard deviation = 8.0
The test results reveal a sample
MEAN=50.
(4 points)
Question: What i

10. s the formula to
calculate the CI (confidence interval) in this example? –
you don’t need to calculate the CI, just show the formula.
11.
A sample of 200 (N=200)
incidents of mass murder reveals that the
mean
number of victims per incident is
50
, with a
standard deviation of 30.
Sample mean=50
S= 30
N=200
Calculate the
85% confidence interval (CI)
for number of victims per mass murder incident and interpret
your results.
(6 points)
12.If a variable has two modes it is called:
(2 points)
unimodal
skewed multimodal
bimodal
Answer:____________

11. A university professor was interested in identifying left-handed
students from all of the six introductory-level psychology
classes in the department. The number of left-handed students
in each class is: 4, 5, 40, 3, 2, 1.
(2 points)
Question:
What is the range?
14.What is the mode for the following distribution of scores?
(3 points)
Eye Color
Frequency
Blue
700
Brown
200
Hazel
832
Green
239

12. 15.
Assume you have administered a worker satisfaction test to
random sample of
N-sample=24 workers
at your company. The test is purported to have a population
standard deviation = 5
The test results reveal a sample
MEAN=60.
(8 points)
Question: Based on the information, develop an estimate of the
mean score for the entire population of workers, using a
80% Confidence Interval.