Statistics Final Exam Questions With Correct Solutions.
Standard deviation rule - accurate answers-68-95-99.7
The distribution of IQ (Intelligence Quotient) is approximately normal in
shape with a mean of 100 and a standard deviation of 14.
According to the standard deviation rule, only % of people have an IQ over
142. - accurate answers-0.15%
If the IQ was over 128 it would be 2.5% and if over 114 it would be 16%
Box plot variability - accurate answers-Box plots that appear longer have
greater variability
A student survey was conducted at a major university, and data were collected
from a random sample of 750 undergraduate students. One variable that was
recorded for each student was the student's answer to the question "With
whom do you find it easiest to make friends? Opposite sex/same sex/no
difference."
These data would be best displayed using which of the following? - accurate
answers-Pie Chart
5 number summary of a boxplot - accurate answers-Min, Q1 (25th percentile),
Median, Q3 (75th percentile), Max
IQR= - accurate answers-Q3-Q1
Range= - accurate answers-maximum - minimum
A researcher wants to determine if preschool attendance is associated with
high school graduation for low-income students. She randomly assigns low-
income children to two groups; one group will attend preschool program, the
second group will not attend preschool. The researcher plans to follow the
children in the study for 20 years and observe whether or not they graduate
from high school.
Which of the following is the response variable in this study? - accurate
answers-Whether or not the student graduates high school.
A study seeks to answer the question, "Does Vitamin C level in the breast milk
of new mothers reduce the risk of allergies in their breastfed infants?" The
,study concluded that high levels of vitamin C (measured in mg) were
associated with a 30 percent lower risk of allergies in the infants.
In this scenario, "levels of vitamin C (measured in milligrams)" is what type of
variable? - accurate answers-Quantitative
Calculate the row percentages for participants who were Not Obese. - accurate
answers-divide non obese dating value by total non obese value, only use
numbers in that row.
A 2009 study analyzed data from the National Longitudinal Study of
Adolescent Health. Participants were followed into adulthood. Each study
participant was categorized as to whether they were obese (BMI >30) or not
and whether they were dating, cohabiting, or married. The researchers were
trying to determine the effect of relationship status on obesity. In this
example, which of the following would it be appropriate to calculate?
Obese 81 103 147 331
Not obese 359 326 277 962
Total 440 429 424 1,293 - accurate answers-Conditional column percentages,
To explore a categorical relationship, the most appropriate summary is the
outcome percentages within each explanatory group.
The outlier on the graph is likely due to an error in recording the data. Which
of the following statements is true? - accurate answers-If the outlier were
removed, the correlation coefficient (r) would increase.
Suppose that the correlation r between two quantitative variables was found
to be r=0. Which of the following is the best interpretation of this correlation
value? - accurate answers-There is no linear relationship between the two
variables.
if r=1 there would be a positive linear relationship and if r=-1 it would be a
negative linear relationship.
When conducting a survey, which of the following is the most important
reason to use a random sample? - accurate answers-To avoid bias and to get a
representative sample.
Which of the following is an example of stratified sampling? - accurate
answers-Proponents of a local ballot measure conduct a survey of the city by
randomly selecting 100 potential voters from each of its 18 zip codes.
, Stratified sampling includes simple random sampling within groups where as
cluster sampling is taking a sample from random whole groups.
The faculty senate at a large university wanted to know what proportion of
the students thought foreign language classes should be required for
everyone. The statistics department offered to cooperate in conducting a
survey, and a simple random sample of 500 students was selected from all the
students enrolled in statistics classes. A survey form was sent by email to
these 500 students.
In this case, which of the following is the population of interest? - accurate
answers-All students at the university.
However the sampling frame only includes students enrolled in a statistics
class so the sample is not representative.
The city council hired three college interns to measure public support for a
large parks and recreation initiative in their city. The interns mailed surveys
to 500 randomly selected participants in the current public recreation
program. They received 150 responses.
True or false? Even though the sample is random, it is not representative of
the population of interest. - accurate answers-True, the sample is not
representative of the population of interest.
Suppose that P(A) = 0.98. Which of the following is the best interpretation of
this statement? - accurate answers-Event A is extremely likely, but in a long
sequence of trials, it occasionally will not occur.
Suppose Joan has a fair four-sided die with sides that are numbered 1, 2, 3,
and 4.
After she rolls it 37 times, Joan finds that she's rolled the number 1 a total of
four times. What is the empirical probability that Joan rolls a 1? - accurate
answers-4/37= 10.81% or .1081
disjoint - accurate answers-2 events can occur at the same time
An urn contains 20 red marbles, 22 blue marbles, and 40 yellow marbles. One
marble is to be chosen from the urn without looking.
What is the probability of choosing a red or a blue marble? - accurate
answers-Use general addition rule for 2 non disjoint events: P(A or B) = P(A) +
P(B) - P(A and B).
Standard deviation rule - accurate answers-68-95-99.7
The distribution of IQ (Intelligence Quotient) is approximately normal in
shape with a mean of 100 and a standard deviation of 14.
According to the standard deviation rule, only % of people have an IQ over
142. - accurate answers-0.15%
If the IQ was over 128 it would be 2.5% and if over 114 it would be 16%
Box plot variability - accurate answers-Box plots that appear longer have
greater variability
A student survey was conducted at a major university, and data were collected
from a random sample of 750 undergraduate students. One variable that was
recorded for each student was the student's answer to the question "With
whom do you find it easiest to make friends? Opposite sex/same sex/no
difference."
These data would be best displayed using which of the following? - accurate
answers-Pie Chart
5 number summary of a boxplot - accurate answers-Min, Q1 (25th percentile),
Median, Q3 (75th percentile), Max
IQR= - accurate answers-Q3-Q1
Range= - accurate answers-maximum - minimum
A researcher wants to determine if preschool attendance is associated with
high school graduation for low-income students. She randomly assigns low-
income children to two groups; one group will attend preschool program, the
second group will not attend preschool. The researcher plans to follow the
children in the study for 20 years and observe whether or not they graduate
from high school.
Which of the following is the response variable in this study? - accurate
answers-Whether or not the student graduates high school.
A study seeks to answer the question, "Does Vitamin C level in the breast milk
of new mothers reduce the risk of allergies in their breastfed infants?" The
,study concluded that high levels of vitamin C (measured in mg) were
associated with a 30 percent lower risk of allergies in the infants.
In this scenario, "levels of vitamin C (measured in milligrams)" is what type of
variable? - accurate answers-Quantitative
Calculate the row percentages for participants who were Not Obese. - accurate
answers-divide non obese dating value by total non obese value, only use
numbers in that row.
A 2009 study analyzed data from the National Longitudinal Study of
Adolescent Health. Participants were followed into adulthood. Each study
participant was categorized as to whether they were obese (BMI >30) or not
and whether they were dating, cohabiting, or married. The researchers were
trying to determine the effect of relationship status on obesity. In this
example, which of the following would it be appropriate to calculate?
Obese 81 103 147 331
Not obese 359 326 277 962
Total 440 429 424 1,293 - accurate answers-Conditional column percentages,
To explore a categorical relationship, the most appropriate summary is the
outcome percentages within each explanatory group.
The outlier on the graph is likely due to an error in recording the data. Which
of the following statements is true? - accurate answers-If the outlier were
removed, the correlation coefficient (r) would increase.
Suppose that the correlation r between two quantitative variables was found
to be r=0. Which of the following is the best interpretation of this correlation
value? - accurate answers-There is no linear relationship between the two
variables.
if r=1 there would be a positive linear relationship and if r=-1 it would be a
negative linear relationship.
When conducting a survey, which of the following is the most important
reason to use a random sample? - accurate answers-To avoid bias and to get a
representative sample.
Which of the following is an example of stratified sampling? - accurate
answers-Proponents of a local ballot measure conduct a survey of the city by
randomly selecting 100 potential voters from each of its 18 zip codes.
, Stratified sampling includes simple random sampling within groups where as
cluster sampling is taking a sample from random whole groups.
The faculty senate at a large university wanted to know what proportion of
the students thought foreign language classes should be required for
everyone. The statistics department offered to cooperate in conducting a
survey, and a simple random sample of 500 students was selected from all the
students enrolled in statistics classes. A survey form was sent by email to
these 500 students.
In this case, which of the following is the population of interest? - accurate
answers-All students at the university.
However the sampling frame only includes students enrolled in a statistics
class so the sample is not representative.
The city council hired three college interns to measure public support for a
large parks and recreation initiative in their city. The interns mailed surveys
to 500 randomly selected participants in the current public recreation
program. They received 150 responses.
True or false? Even though the sample is random, it is not representative of
the population of interest. - accurate answers-True, the sample is not
representative of the population of interest.
Suppose that P(A) = 0.98. Which of the following is the best interpretation of
this statement? - accurate answers-Event A is extremely likely, but in a long
sequence of trials, it occasionally will not occur.
Suppose Joan has a fair four-sided die with sides that are numbered 1, 2, 3,
and 4.
After she rolls it 37 times, Joan finds that she's rolled the number 1 a total of
four times. What is the empirical probability that Joan rolls a 1? - accurate
answers-4/37= 10.81% or .1081
disjoint - accurate answers-2 events can occur at the same time
An urn contains 20 red marbles, 22 blue marbles, and 40 yellow marbles. One
marble is to be chosen from the urn without looking.
What is the probability of choosing a red or a blue marble? - accurate
answers-Use general addition rule for 2 non disjoint events: P(A or B) = P(A) +
P(B) - P(A and B).
