Experimental Design Concepts

Dependent Variable

• The variable that responds to the changed variable. (responding variable)

• The variable that is manipulated in an experiment.

• The variable that remains constant throughout the experiment.

• The variable that is measured at the end of an experiment.

Independent Variable

• A variable that is changed by the person conducting the experiment. (manipulated)

• A variable that remains constant throughout the experiment.

• A variable that is measured in response to changes in the independent variable.

• A variable that is not affected by any other variables.

Pie Graph

• Used to show how a fixed quantity is broken into parts.

• Used to display trends over time.

• Used to compare different categories of data.

• Used to illustrate the relationship between two variables.

Control Group

• The group that receives the experimental treatment.

• The standard for comparison--receives no experimental treatment.

• A group that is exposed to a different variable.

• The group that is monitored for changes without intervention.

Experimental Group

• The group that receives some type of experimental treatment.

• The group that does not receive any treatment.

• The group that is used for comparison purposes.

• The group that receives a placebo treatment.

Line Graph

• Used to show trends or continuous change in data.

• Used to compare different categories of data.

• Used to display data in a circular format.

• Used to represent data in a tabular form.

Hypothesis

• A reasonable educated explanation.

• A random guess without evidence.

• A definitive conclusion based on facts.

• An untestable theory.

Graph

• A diagram used to show the relationship between 2 variables.

• A type of chart that displays data in a circular format.

• A visual representation of numerical data in a table.

• A method for organizing data in a linear sequence.

Constants

• Parts of the experiment that are kept the same.

• Variables that change during the experiment.

• The main hypothesis of the experiment.

• The equipment used in the experiment.

Controlled Experiment

• An experiment in which multiple variables are changed simultaneously.

• An experiment in which only 1 variable is changed. All other variables remain the same.

• An experiment that does not require any control over variables.

• An experiment that is conducted without any hypothesis.