Question 1

A person has a score that is in the bottom 42% of the scores. What is the highest Z score this person could have? (Assume a normal distribution.)

Accepted Answer

A) -1.41 
B) -)94 
C) -)20 
D) +)25

Question 2

On a test of physical fitness, 18-year-olds' scores are normally distributed with a mean of 140 and a standard deviation of 25.
a. Approximately what percentage of 18-year-olds have scores above 190? Below 165? Below 115?
Use the normal curve approximation rules and be sure to include a sketch.
b. Explain your answers and procedure to a person who is not familiar with the normal curve or normal curve areas.

Accepted Answer

The answer of On a test of physical fitness, 18-year-olds'...

Question 3

Survey organizations in the United States today are not allowed to call ____________ , creating some bias in the poll results.

Accepted Answer

A) individuals of African American descent 
B) individuals over the age of 60 
C) cell phones 
D) registered voters

Question 4

__________ selection is a procedure of selecting a sample of individuals to study such that each individual in the population has an equal chance of being selected.

Accepted Answer

The answer of __________ selection is a procedure of selecting...

Question 5

Relative frequency is:

Accepted Answer

A) the expected number of times you will obtain a particular outcome in an experiment 
B) how frequently a result occurs 
C) what result you expect if you repeat an experiment frequently 
D) the number of times something occurs relative to the number of times it could have occurred

Question 6

In almost any published research article, the Results section will describe the methods associated with determining statistical significance, followed by something like: "p < .05 or p < .01." (True or False)

Accepted Answer

A) True 
 B)False

Question 7

In __________ sampling, the researcher often begins with a complete list of all the members of the population.

Accepted Answer

The answer of In __________ sampling, the researcher often begins...

Question 8

Today, survey sampling uses complex methods in order to ensure a close approximation to true __________ sampling.

Accepted Answer

The answer of Today, survey sampling uses complex methods in...

Question 9

The Gallup Poll correctly predicted George H. W. Bush's 1988 victory using only 4,089 interviews. Why, then, did the Gallup Poll in 1948 wrongly predict Dewey's victory over Truman when they used 50,000 interviews to make the prediction?

Accepted Answer

A) They only interviewed people in one state 
B) They used multistage cluster sampling 
C) They used quota sampling 
D) They used random sampling

Question 10

A(n)__________ shows the percentage of scores between the mean and any particular Z score.

Accepted Answer

The answer of A(n)__________ shows the percentage of scores between...

Question 11

To change a proportion into a percent:

Accepted Answer

A) divide by 10 
B) multiply by 100 
C) take the square root of the value 
D) multiply by 10

Exam 4: Some Key Ingredients for Inferential Statistics: the Normal Curve, Sample Versus Population, and Probability