Question

Besides your independent variable, what other factors (additional variables, additional types of information) might you consider in trying to improve your understanding of the relationship between the assigned independent and dependent variable? Why? Be sure to specifically address the strength of the relationship you uncovered in the previous question. Do not provide a general discussion of regression.

Answer 1

Besides independent variables, we also need to identify any extraneous variables that might be impacting the outcome - such variables which have not been included in the regression model because of unavailability of data or difficulty in gathering such data.

Additionally, there might be confounding variables which could impact both the independent and dependent variables and lead to a change in the response in addition to that explained by the independent variables in the model. Also, there can be lurking variables which are variables not included as an explanatory or response variable in the model but affect the response. Such lurking variables can lead to a false impression of strong relationship, or even hide the true relationship between the variables.

It is important to know and consider the implications of these variables on the modeling process. If required, it might make sense to include some additional variables to make the model more robust.