1. Chapter 3: The Experimental Research Approach Introduction Introduction –Goal is to discover the effects of presumed causes This multimedia product and its contents are protected under copyright law. The following are prohibited by law: Any public performance or display, including transmission of any image over a network; Any public performance or display, including transmission of any image over a network; Preparation of any derivative work, including the extraction, in whole or in part, of any images; Preparation of any derivative work, including the extraction, in whole or in part, of any images; Any rental, lease, or lending of the program Any rental, lease, or lending of the program

2. Causation Cause Cause –contextually dependent Effect-the difference between what would and what did happen Effect-the difference between what would and what did happen Causal relationship-what evidence is needed Causal relationship-what evidence is needed –John Stuart Mills Canons Method of agreement Method of agreement Method of difference Method of difference Joint methods of agreement and difference Joint methods of agreement and difference Method of concomitant variation Method of concomitant variation

3. –Identified the necessary and sufficient conditions for the occurrence of an event -- Causation viewed as a large network of cause- and-effect relations

4. The Psychological Experiment Criteria for identifying a causal relation Criteria for identifying a causal relation –Cause must precede the effect –Cause must be related to the effect –No other explanations must exist for the effect Definition of the psychological experiment Definition of the psychological experiment –Objective observation –Of phenomenon that are made to occur –In a strictly controlled situation –Where one or more factors are varied and the others are kept constant

5. Advantages of the experimental method Causal inference Causal inference –Causal description –Causal explanation Control Control Ability to manipulate variables Ability to manipulate variables

6. Disadvantages of the experimental approach Does not test effect of nonmanipulated variables—age, weather, etc Does not test effect of nonmanipulated variables—age, weather, etc Artificiality Artificiality Inadequate method of scientific inquiry Inadequate method of scientific inquiry

7. Experimental research settings Field experimentation Field experimentation –Disadvantage-less control of extraneous variables Laboratory experimentation Laboratory experimentation –Strength is control over extraneous variables –Weakness—artificiality

8. Internet experiments Internet experiments –Advantages Access to diverse population Access to diverse population Bring experiment to participant Bring experiment to participant Large sample Large sample Direct access to motivational confounding Direct access to motivational confounding Cost savings—lab space, equipment, etc Cost savings—lab space, equipment, etc –Disadvantages Lack of control Lack of control Self-selection Self-selection Dropout Dropout