1. Dependent v. Independent Variables
What’s the difference?

2. What is a Variable? Simply, something that varies.
Specifically, variables represent persons or objects that can be manipulated, controlled, or merely measured for the sake of research.
Variation: How much a variable varies. Those with little variation are called constants.

3. Independent Variables
These variables are ones that are more or less controlled.
You might manipulate these variables as needed.
They still vary, but the variation is relatively known (like seconds, or days)
It is easy to figure the next independent variable.

4. Dependent Variables
Dependent variables are not controlled or manipulated, but instead are simply measured.
Dependent Variables depend on what the independent variable is.

5. Independent V. Dependent
Intentionally manipulated
Controlled
Vary at known rate
Cause
Intentionally left alone
Measured
Vary at unknown rate
Effect

6. Graphing Dependent v. Independent Variables

7. Example
Time to roll down the ramp 5 10 15 20 25
Height of a ramp (cm)

8. Summary
Independent is the x axis
Independent is the x coordinate
Dependent is the y axis
Dependent is the y coordinate