WGU C955 - Module 6: Correlation & Regression / 60
Questions And Answers Graded (A+)
Quiz : 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.
Quiz :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
Quiz :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
Quiz :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.
Quiz :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
Quiz :{{ 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
Quiz :Which correlation coefficient suggests the weakest correlation?
a −0.9
b −0.3
c 0.1
d 1 - Answer :0.1
Quiz :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.
Quiz :What is the process used to create the equation for the line of best fit?
a Completing the square
b Least squares estimation
c Fitting the line to the curve
d Linear approximation - Answer :Least squares estimation
Quiz :A relationship between two or more variables is known as a(n) ________.
a Causation
b Association
c Cause and effect
d Correlation - Answer :Association
Quiz :Using a line of best fit in slope-intercept form, y=mx+b , what must be true
if there is a positive correlation?
a m must be >0 .
b b must be >0 .
c Both m and b must be >0 .
d Both m and b must have the same sign. - Answer :m must be >0.
Quiz :Consider the following equation, y=−3.2x+2.8 . What is the y -intercept for
this equation?
a −3.2
b 3.2
c 2.8
d −2.8 - Answer :2.8
Questions And Answers Graded (A+)
Quiz : 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.
Quiz :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
Quiz :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
Quiz :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.
Quiz :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
Quiz :{{ 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
Quiz :Which correlation coefficient suggests the weakest correlation?
a −0.9
b −0.3
c 0.1
d 1 - Answer :0.1
Quiz :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.
Quiz :What is the process used to create the equation for the line of best fit?
a Completing the square
b Least squares estimation
c Fitting the line to the curve
d Linear approximation - Answer :Least squares estimation
Quiz :A relationship between two or more variables is known as a(n) ________.
a Causation
b Association
c Cause and effect
d Correlation - Answer :Association
Quiz :Using a line of best fit in slope-intercept form, y=mx+b , what must be true
if there is a positive correlation?
a m must be >0 .
b b must be >0 .
c Both m and b must be >0 .
d Both m and b must have the same sign. - Answer :m must be >0.
Quiz :Consider the following equation, y=−3.2x+2.8 . What is the y -intercept for
this equation?
a −3.2
b 3.2
c 2.8
d −2.8 - Answer :2.8
