WGU C955 - Module 6: Correlation &
Regression Questions & Answers 100%
Accurate
A researcher wants to know if there was a relationship between student age and desire
to complete a college degree. To answer this question, the researcher used a local
community college as the sampling frame and then used stratified sampling to get a
sample of students from 18 to 80 years old. Based on the information given, is there any
potential bias in this study?
a Yes, because the sampling frame does not match the intended population of the
question.
b Yes, because the sampling method will not give a representative sample.
c Yes, because a voluntary sample should have been used.
d No, there will likely be no bias in this study. - ANSWER-Yes, because the sampling
frame does not match the intended population of the question.
A researcher conducts an observational study and finds a correlation between
managers' income and the number of college credits earned. The correlation coefficient
was r=.85 with a regression equation of y=515x+12000. What can you say about the
relationship between these variables?
a There is an association between these variables
b There is a causation between these variables.
c There is no relationship between these variables.
d There is not enough information to determine the relationship between the variables. -
ANSWER-There is an association between these variables
What technique is used to estimate the profit margin for a production level of 25
thousand units, if a line of best fit is created to estimate profit margin for production
levels between 20 to 39 thousand units?
a Interpolation
b Linearization
c Extrapolation
d Internalization - ANSWER-Interpolation
What is the most appropriate definition of a scatterplot?
, a A graph that uses dots to demonstrate relationships between two categorical
variables.
b A graph where lines are shown to represent positive or negative trends.
c A graph where the explanatory and response variables are plotted as ordered pairs.
d A graph where a positive causation is always represented with dots forming a straight
line. - ANSWER-A graph where the explanatory and response variables are plotted as
ordered pairs.
What does a strong positive correlation between two variables suggest?
a The explanatory variable is increasing and the response variable is decreasing
b There is an association between the variables
c There is a causation between the variables
d Cannot determine - ANSWER-There is an association between the variables
{{ Scatterplot of distance from city center vs. rent. The linear equation for this scatterplot
is y equals negative one hundred five ten thousandths times x plus ten and three
hundred eighty one thousandths. }}
Using the scatterplot Distance from City Center vs. Monthly Rent, how far can we
expect an apartment to be from the city center if the monthly rent is $ 980 ? Round your
answer to the nearest mile.
a Around 54 miles
b Around 55 miles
c Around 56 miles
d Around 57 miles - ANSWER-Around 55 miles
Which correlation coefficient suggests the weakest correlation?
a −0.9
b −0.3
c 0.1
d 1 - ANSWER-0.1
What does it mean for a result or relationship to be statistically significant?
a The relationship is not caused by mere chance.
b The relationship is caused by chance.
c Your hypothesis test has failed.
d Your significance level is not high enough. - ANSWER-The relationship is not caused
by mere chance.
What is the process used to create the equation for the line of best fit?
a Completing the square
b Least squares estimation
Regression Questions & Answers 100%
Accurate
A researcher wants to know if there was a relationship between student age and desire
to complete a college degree. To answer this question, the researcher used a local
community college as the sampling frame and then used stratified sampling to get a
sample of students from 18 to 80 years old. Based on the information given, is there any
potential bias in this study?
a Yes, because the sampling frame does not match the intended population of the
question.
b Yes, because the sampling method will not give a representative sample.
c Yes, because a voluntary sample should have been used.
d No, there will likely be no bias in this study. - ANSWER-Yes, because the sampling
frame does not match the intended population of the question.
A researcher conducts an observational study and finds a correlation between
managers' income and the number of college credits earned. The correlation coefficient
was r=.85 with a regression equation of y=515x+12000. What can you say about the
relationship between these variables?
a There is an association between these variables
b There is a causation between these variables.
c There is no relationship between these variables.
d There is not enough information to determine the relationship between the variables. -
ANSWER-There is an association between these variables
What technique is used to estimate the profit margin for a production level of 25
thousand units, if a line of best fit is created to estimate profit margin for production
levels between 20 to 39 thousand units?
a Interpolation
b Linearization
c Extrapolation
d Internalization - ANSWER-Interpolation
What is the most appropriate definition of a scatterplot?
, a A graph that uses dots to demonstrate relationships between two categorical
variables.
b A graph where lines are shown to represent positive or negative trends.
c A graph where the explanatory and response variables are plotted as ordered pairs.
d A graph where a positive causation is always represented with dots forming a straight
line. - ANSWER-A graph where the explanatory and response variables are plotted as
ordered pairs.
What does a strong positive correlation between two variables suggest?
a The explanatory variable is increasing and the response variable is decreasing
b There is an association between the variables
c There is a causation between the variables
d Cannot determine - ANSWER-There is an association between the variables
{{ Scatterplot of distance from city center vs. rent. The linear equation for this scatterplot
is y equals negative one hundred five ten thousandths times x plus ten and three
hundred eighty one thousandths. }}
Using the scatterplot Distance from City Center vs. Monthly Rent, how far can we
expect an apartment to be from the city center if the monthly rent is $ 980 ? Round your
answer to the nearest mile.
a Around 54 miles
b Around 55 miles
c Around 56 miles
d Around 57 miles - ANSWER-Around 55 miles
Which correlation coefficient suggests the weakest correlation?
a −0.9
b −0.3
c 0.1
d 1 - ANSWER-0.1
What does it mean for a result or relationship to be statistically significant?
a The relationship is not caused by mere chance.
b The relationship is caused by chance.
c Your hypothesis test has failed.
d Your significance level is not high enough. - ANSWER-The relationship is not caused
by mere chance.
What is the process used to create the equation for the line of best fit?
a Completing the square
b Least squares estimation
