Chapter 1Experimentation

Experimental group- group in an experiment that is exposed to the treatment

Control group- group in an experiment that is not exposed to the treatment

Groups

Placebo- inactive substance◦ In order to test the effectiveness of a treatment, a

placebo is used on the control group◦ Usually it will be a sugar pill

Placebo

results controlled by expectations alone◦ In other words, sometimes a placebo is effective

because the participants BELIEVE that they are really receiving the treatment

Placebo effect-

Experiment: If employees are allowed to take a nap during lunch, will they be more productive in the afternoon?

Independent variables- the factor that is being

manipulated, the variable whose effect is being studied◦ Ex: nap

Dependent variables- the factor that depends on the independent variable◦ Ex: productivity

Variables

neither the participants or the researchers know who received the real treatment◦ Why would the double-blind procedure be more

effective?

Double-blind procedure-