Identify the Dependent and Independent Variables. A study was done to find if different tire treads affect the braking distance of a car. The height of bean plants depends on the amount of water they receive. Lemon trees receiving the most water produced the most lemons.

Independent Variable Is the variable that you have control over. Ex. The time it takes to run a mile depends on the person’s running speed. The independent variable - the person’s speed. That’s what you can control.

Dependent Variable A variable whose value depends on that of another. Ex. The time it takes to run a mile depends on that person’s running speed. Ex. Dependent variable - time - The time it takes depends on the speed the person is running.

Control Group In a scientific experiment is a group separated from the rest of the experiment where the independent variable being tested cannot influence the results. Ex. Testing a new medication and giving half of the group the new medication and the other half ( control group) a sugar pill.

Reliability – The degree to which an assessment tool produces stable and consistent results

Validity Being able to produce the desired results repeatedly.