Experimental Design, Variables, and Scientific Hypotheses

Experimental Design, Variables, and Scientific Hypotheses

The GED Science test emphasizes understanding scientific investigations rather than memorizing trivia.

Core Elements of Controlled Experiments

• Hypothesis: A testable, falsifiable prediction (often phrased as "If [independent variable], then [dependent variable]").
• Independent Variable (IV): The factor that the scientist deliberately changes or manipulates (plotted on the $x$-axis).
• Dependent Variable (DV): The factor that is measured or observed in response to the IV (plotted on the $y$-axis).
• Controlled Variables (Constants): All other conditions kept identical across experimental and control groups to ensure a fair test.
• Control Group: The baseline group that does not receive experimental treatment, used for comparison.