What is the difference between floor effects and ceiling effects?
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The difference between floor effect and ceiling effects is that each one is the opposite of the other. The ceiling effect usually happens when the exam given is too easy that all testers score very high, and the floor effect occurs when the examination is too difficult where most examinees score very low.
Example / Application
Application: These images show an example of both a floor effect and a ceiling effect. As you can see, the direction of both effects are the opposite of each other, for floor effects, the impact is shown by a downward direction, and for the ceiling effect, the impact is shown as a rising effect.
Lammers, W. J., and Badia, P. (2005). Fundamental of Behavioral Research. California: Thomson and Wadsworth.