2.  Allows researchers to detect cause and effect relationships  Researchers manipulate a variable and observe whether any changes occur in a second variable

3.  Purpose of experiments: How one variable X causes changes in another variable Y. How X effects Y ( Cause and Effect ) X is the INDEPENDENT VARIABLE Y is the DEPENDENT VARIABLE

4.  Condition or event that an experimenter varies in order to see its impact on another variable.  Experimenter controls or manipulates  It is hypothesized to have some effect on the dependent variable  Experiment is conducted to verify the effect

5.  Variable thought to be affected by manipulation of the independent variable  Usually a measurement of participants behavior

6.  Experimental Group: Receive some special treatment - ( they receive the Independent Variable )  Control Group: Receives no special treatment

7.  Any differences between experimental and control groups not caused by the independent variable  Or Any variable other than the independent variable that seem likely to influence the dependent variable

9. Any variable that can confuse the results of the experiment.

10.  All subjects have an equal chance of being assigned to any group or condition in the study.

12. Experimental Group 1. IV applied 2. DV measured Control Group 1. NO IV 2. DV measured

13.  Single Group – exposing single group to both conditions ( Within Subjects Design )  Between Subjects Design – comparisons are used between 2 different groups  Possible to manipulate more than one independent variable  More than one dependent variable can be measured.

14.  Artificial – the experiment can cause doubts about applicability  Ethical Concerns – experiments cannot be conducted if they could cause harm to the participants.