2. Definition
• Experimentation involves the manipulation
of one or more variables by the
experimenter in such a way that its effect
on one or more other variables can be
measured.
3. Independent Variable & Dependent Variable
• A variable being manipulated is called the
independent variable.
• A variable that will reflect the impact of
independent variable is called a
dependent variable.
4. Treatment & Control Group
• A group exposed to a manipulation of the
independent variable is known as a
treatment group.
• A group in which the independent variable
is unchanged is called the control group.
5. Randomization or Matching
• Randomization involves randomly
assigning subjects to treatment or control
groups.
• It is to ensure that the independent
variable is the only variable that differs
between the groups.
6. Purpose of Experimentation
• To establish and measure causal
relationships among the variables.
• To control other potential causal factors
(extraneous variables).
