Independent variables (

1. Central Tendency, Spread, or Symmetry?
How many independent variables are there
in your question?
The independent variable is the thing doing
One Two or More Zero

2. Central Tendency, Spread, or Symmetry?
What is an independent variable?
The independent variable is the thing doing

3. Central Tendency, Spread, or Symmetry?
What is an independent variable?
The independent variable influences the dependent variable.

4. Central Tendency, Spread, or Symmetry?
independent Variable Dependent Variable
Does Age influence Driving speed?
Do Bonuses influence Employee productivity?
Do Promotions influence Employee retention?
What is an independent variable?
The independent variable influences the dependent variable.

5. Example of a question with
ONE independent variable

6. Example of a question with
ONE independent variable
Does the new employee self-initiative plan effect
employee productivity?
1

7. Example of a question with
TWO independent variables

8. Example of a question with
TWO variables of interest
Does the new employee self-initiative plan and
getting a bonus or not effect employee
productivity?
1
2

9. Example of a question with
ZERO independent variables

10. Example of a question with
ZERO independent variables
Does the sample of 32 State College student IQ scores
significantly different than the population of IQ scores?
In this example, a case is being made to determine if
the sample belongs to the population. If that is the
case there are no separate groups, therefore, it could
be said that there is no independent variable.

11. In summary
One independent (Independent Variable): Who drives
faster on average on the freeway in state drivers or out of
state drivers? (Independent variable = driver residence)
Two independent (Independent Variables): Who drives
faster on average on the freeway in state (older/younger)
drivers or out of state (older/younger) drivers?
(Independent variable = driver residence / age groups)
Zero independent (Independent Variables): Do a sample
of drivers drive the same speed on average as the
population? (zero independent variables)

12. In summary
One independent (Independent Variable): Who drives
faster on average on the freeway in state drivers or out of
state drivers? (Independent variable = driver residence)
Two independent (Independent Variables): Who drives
faster on average on the freeway in state (older/younger)
drivers or out of state (older/younger) drivers?
(Independent variable = driver residence / age groups)
Zero independent (Independent Variables): Do a sample
of drivers drive the same speed on average as the
population? (zero independent variables)

13. In summary
One independent (Independent Variable): Who drives
faster on average on the freeway in state drivers or out of
state drivers? (Independent variable = driver residence)
Two independent (Independent Variables): Who drives
faster on average on the freeway in state (older/younger)
drivers or out of state (older/younger) drivers?
(Independent variable = driver residence / age groups)
Zero independent (Independent Variables): Do a sample
of drivers drive the same speed on average as the
population? (zero independent variables)

14. Let’s Practice!

15. How many independent variables are there in
each question that follows?

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

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

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

19. Does the morning, afternoon, or evening shifts
have the highest employee satisfaction rates?
independent Variable Dependent Variable
Assigned shift influence Employee satisfaction rates
One Two or MoreZero

20. Next Example

21. Is there a significant difference between the type of
training received and whether one is college
educated or not in terms of agent commission?
One Two or MoreZero

22. Is there a significant difference between the type of
training received and whether one is college
educated or not in terms of agent commission?
One Two or MoreZero

23. Is there a significant difference between the type of
training received and whether one is college
educated or not in terms of agent commission?
One Two or MoreZero

24. Is there a significant difference between the type of
training received and whether one is college
educated or not in terms of agent commission?
independent Variable Dependent Variable
Type of training Agent commission
College educated or not
One Two or MoreZero

25. Next Example

26. Which training method (A, B, or C) brings about
greater trainee proficiency?
One Two or MoreZero

27. Which training method (A, B, or C) brings about
greater trainee proficiency?
One Two or MoreZero

28. Which training method (A, B, or C) brings about
greater trainee proficiency?
One Two or MoreZero

29. Which training method (A, B, or C) brings about
greater trainee proficiency?
independent Variable Dependent Variable
Training Method Training proficiency
One Two or MoreZero

30. Final Example

31. Does a sample of freshmen have significantly more
or less cyberbullying incidents than high school
students in general?
One Two or MoreZero

32. Does a sample of freshmen have significantly more
or less cyberbullying incidents than high school
students in general?
One Two or MoreZero

33. Does a sample of freshmen have significantly more
or less cyberbullying incidents than high school
students in general?
One Two or MoreZero
In this example, a case is being made to determine if
the sample belongs to the population. If that is the
case there are no separate groups, therefore, it could
be said that there is no independent or independent
variable.

34. Central Tendency, Spread, or Symmetry?
How many independent or independent
variables are there in your question?
The independent variable is the thing doing
One Two or MoreZero