WGU C955 Applied Probability and
Statistics - - Module 6: Correlation and
Regression with Complete Solutions
lurking variable - ANSWER-A variable that is not included in an analysis but that is
related to two (or more) other associated variables which were analyzed.
observational study - ANSWER-The researcher observes if there is an association
between variables. There is no treatment or control group.
sampling method - ANSWER-The technique used to select people within the sampling
frame.
correlation - ANSWER-An observed relationship between two quantitative variables.
While this is most commonly a linear relationship, it does not need to be. Note that
observing a relationship does NOT imply that there is a meaningful causal link between
the variables.
coordinate plane - ANSWER-A tool for graphing consisting of a horizontal x-axis and a
vertical y-axis.
correlation coefficient - ANSWER-A measure of the linear relationship between two
attributes. The numerical value demonstrates how closely the attributes vary together.
Correlation coefficients near -1 and +1 have strong linear correlation, while a correlation
coefficient near 0 has weak (or no) linear correlation.
linear interpolation - ANSWER-Estimation using the linear regression equation in
between known data points.
least squares - ANSWER-A technique for finding the regression line.
voluntary sample - ANSWER-Researchers invite everyone in the sampling frame to
participate. Individuals who voluntarily respond comprise the study sample.
scatterplot - ANSWER-A graph that uses dots on a coordinate plane to show the
relationship between variables.
representative sample - ANSWER-A subset of the population with similar characteristics
to the entire population.
Statistics - - Module 6: Correlation and
Regression with Complete Solutions
lurking variable - ANSWER-A variable that is not included in an analysis but that is
related to two (or more) other associated variables which were analyzed.
observational study - ANSWER-The researcher observes if there is an association
between variables. There is no treatment or control group.
sampling method - ANSWER-The technique used to select people within the sampling
frame.
correlation - ANSWER-An observed relationship between two quantitative variables.
While this is most commonly a linear relationship, it does not need to be. Note that
observing a relationship does NOT imply that there is a meaningful causal link between
the variables.
coordinate plane - ANSWER-A tool for graphing consisting of a horizontal x-axis and a
vertical y-axis.
correlation coefficient - ANSWER-A measure of the linear relationship between two
attributes. The numerical value demonstrates how closely the attributes vary together.
Correlation coefficients near -1 and +1 have strong linear correlation, while a correlation
coefficient near 0 has weak (or no) linear correlation.
linear interpolation - ANSWER-Estimation using the linear regression equation in
between known data points.
least squares - ANSWER-A technique for finding the regression line.
voluntary sample - ANSWER-Researchers invite everyone in the sampling frame to
participate. Individuals who voluntarily respond comprise the study sample.
scatterplot - ANSWER-A graph that uses dots on a coordinate plane to show the
relationship between variables.
representative sample - ANSWER-A subset of the population with similar characteristics
to the entire population.
