The document discusses explanatory variables and examples of questions with one or two explanatory variables. An explanatory variable is the thing that does the influencing in a study. A question with one explanatory variable determines if that single variable influences an outcome. A question with two explanatory variables examines the influence of two variables, such as whether a new plan increases productivity and whether years of experience also impacts productivity.

1. You will remember that the variable of interest is the thing
being influenced
Central Tendency, Spread, or Symmetry?
Does Age influence Driving Speed?
Do Bonuses influence Employee Productivity?
Do Promotions influence Employee Retention?

2. What is an explanatory variable?
Central Tendency, Spread, or Symmetry?

3. What is an explanatory variable?
The explanatory variable is the thing doing the influencing
Central Tendency, Spread, or Symmetry?

4. What is an explanatory variable?
The explanatory variable is the thing doing the influencing
Central Tendency, Spread, or Symmetry?
Does Age influence Driving Speed?
Do Bonuses influence Employee Productivity?
Do Promotions influence Employee Retention?

5. Example of a question with
ONE explanatory variable

6. Example of a question with
ONE explanatory variable
Does the new employee self-initiative plan increase
employee productivity?
You determine if a group who uses the plan has greater
productivity than a group that doesn’t.

7. Example of a question with
ONE explanatory variable
Does the new employee self-initiative plan increase
employee productivity?
You determine if a group who uses the plan has greater
productivity than a group that doesn’t.
Explanatory variable = group
status or whether a group
uses the plan or not

8. Example of a question with
TWO variables of interest

9. Example of a question with
TWO variables of interest
Does the new employee self-initiative plan increase employee
productivity?
You determine if a group who uses the plan has greater
productivity than a group that doesn’t. You also want to
determine if the number of years they’ve been on the job effects
productivity

10. Example of a question with
TWO variables of interest
Does the new employee self-initiative plan increase employee
productivity?
You determine if a group who uses the plan has greater
productivity than a group that doesn’t. You also want to
determine if the number of years they’ve been on the job effects
productivity
Explanatory variables =
(1) group status and
(2) years on the job

11. Let’s Practice!

12. How many explanatory variables are there in
each question that follows?

13. One Two or More
Does the morning, afternoon, or evening shifts
have the highest employee satisfaction rates?

14. One Two or More
Does the morning, afternoon, or evening shifts
have the highest employee satisfaction rates?

15. One Two or More
Does the morning, afternoon, or evening shifts
have the highest employee satisfaction rates?

16. One Two or More
Does the morning, afternoon, or evening shifts
have the highest employee satisfaction rates?
Explanatory variable = Shift Status

17. Next Example

18. One Two or More
Does product A or B produce higher profits?
Furthermore, does the production location
(domestic or international) impact profits for
these two products?

19. One Two or More
Does product A or B produce higher profits?
Furthermore, does the production location
(domestic or international) impact profits for
these two products?

20. One Two or More
Does product A or B produce higher profits?
Furthermore, does the production location
(domestic or international) impact profits for
these two products?
Explanatory variable = Product Type

21. One Two or More
Does product A or B produce higher profits?
Furthermore, does the production location
(domestic or international) impact profits for
these two products?
Explanatory variable = Product Type
Explanatory variable =
Production Location