Practice Exam
Questions 1-5 are based on the following description
An advertising firm is conducting a survey of adult
South Carolinians about the effectiveness of different
advertising campaigns to promote tourism in Florida.
Using the most recent voter registration lists, they
select a simple random sample of 4,000 registered
voters and mail them a survey and $1 (to make
people feel more inclined to respond). They send a
second reminder envelope (without the $1) to those
who hadn’t responded after three weeks. In the end
they receive responses from 1,235 people.
1) The sample is:
A)
B)
C)
D)
E)
mail
Adult South Carolinians
Registered voters in South Carolina
The 1,235 people who responded
The 2,765 people who did not respond
The 4,000 people who received the survey in the

2) The sampling frame is:
A)
B)
C)
D)
E)
Adult South Carolinians
Registered voters in South Carolina 
The 1,235 people who responded
The 2,765 people who did not respond
The 4,000 people who received the survey in the mail
3) The error caused by 2,765 people who chose not to
send their survey back is:
A) A type of nonsampling error caused by nonresponse

B) A type of nonsampling error caused by
undercoverage
C) A type of sampling error caused by nonresponse
D) A type of sampling error caused by undercoverage
4) Imagine that instead of surveying the entire state at
once using a single simple random sample, they first
broke the state into three regions (the Lowcountry,
Midlands, and Upstate) and took a random sample of
registered voters from each of those three regions. This
would be an example of a:
A)
B)
C)
D)
E)
Census
Cluster Sample
Convenience Sample
Stratified Random Sample 
Systematic Sample
5) That people who were more interested in vacationing
in Florida were more likely to respond than those who
had no interest probably:
A) Made the results biased 
B) Made the results less variable
C) Made the results more variable
Questions 6-10 are based on the following description
The Pew Research Center recently conducted a survey
to see what percentage of American adults say they
most admire political leaders who stick to their positions
(as opposed to making compromises). The poll was
conducted by telephone from September 16-19 and had
1,005 responses from adults with phone lines living in
the continental United States. 492 of those responding
said they favored leaders who stick to their positions.
Ans: D
Ans: B
8) The population is:
A) American adults 
B) Adults with phone lines living in the US
C) The 1,005 who responded
D) The percentage of American adults who said they
favored leaders who stick to their positions
E) The percentage of the 1,005 who responded who
said they favored leaders who stick to their positions
9) The parameter is:
A) American adults
B) Adults with phone lines living in the US
C) The 1,005 who responded
D) The percentage of American adults who said they
favored leaders who stick to their positions 
E) The percentage of the 1,005 who responded who
said they favored leaders who stick to their positions
Questions 11-13 are based on the following description
A team of researchers wished to study whether oatmeal
reduced bad cholesterol levels in those who ate it. They
found 500 adults over age 40 who regularly eat oatmeal
or products from oatmeal. They then matched each of
these 500 with a similar adult (one of the same gender,
within 10 pounds of the same weight, and who exercised
roughly the same amount) who did not regularly eat
oatmeal or products made from oatmeal. Finally, they
measured the bad cholesterol LDL for each adult and
compared both groups.
11) This is NOT an experiment because:
A) It used matched pairs
B) It was not at least single-blind
C) The researcher did not assign the adults to regularly
eat oatmeal or not 
D) The researcher did not use randomness
E) The sample size wasn’t large enough
12) The individuals in this observational study were:
A) The 500 non-oatmeal eaters
B) The 500 who regularly ate oatmeal
C) The combined 500 oatmeal eaters and 500 nonoatmeal eaters 
D) The researchers
E) Eating oatmeal and not eating oat-meal
Questions 17-23 are based on the following paragraph
A team of researchers is attempting to examine the
effect of an herbal chewing gum for the prevention of
hay-fever symptoms. The researchers select 240
subjects from hay-fever allergy patients at six clinics
scattered around the country. The 240 subjects are
randomly split into two groups, one receiving the herbal
chewing gum, and one receiving a standard chewing
gum with the same flavor but none of the active herbal
ingredients. Neither the doctors nor the patients know
which gum was used in each case. At the end of three
weeks the subjects are judged based on their amount of
nasal congestion.
17) Explanatory variable(s) in this experiment include:
A) Amount of nasal congestion after 3 weeks
B) Using herbal chewing-gum and non-herbal chewing
gum 
C) Whether the patient was also allergic to dust or not
D) Two of the above are correct
18) Response variable(s) in this experiment include:
A) Amount of nasal congestion after 3 weeks 
B) Using herbal chewing-gum and non-herbal chewing
gum
C) Whether the patient was also allergic to dust or not
D) Two of the above are correct
19) That neither the doctors nor the patients know
which gum was received in each case makes this study:
A) Completely randomized
B) Double blind 
C) Matched pairs
D) Single blind
23) One alternative design would be to divide the
subjects into two groups, one with dust allergies and one
without dust allergies. Half of those with a dust allergy
would be assigned to each treatment, and similarly half
of those without a dust allergy would be assigned to
each treatment. This would make the study a:
A) Block design 
B) Completely randomized design
C) Matched-pairs design
D) Both A and C