The Experimental Method

• What is an aim?

  A general statement of what the researcher intends to investigate, or, the purpose of the study.
• What are aims developed from?

  Theories, which are based on many hours of research.
• What is a hypothesis?


  A clear and testable statement that outlines the relationship between the variables to be investigated, usually stated at the outset of any study.
• What are the two types of hypotheses?


  Directional and non-directional.
• What is a directional hypothesis?


  When the researcher makes their prediction for the outcome of the study clear, outlining the anticipated difference between the conditions.
• What is a non-directional hypothesis?


  A hypothesis that states there will be a difference between variables, but the difference remains unspecified.
• When do researchers use a directional hypothesis?


  When a theory or findings from a previous study suggest a particular outcome.
• When do researchers use a non-directional hypothesis?


  When there is no previous research, or earlier studies show contradictory findings.
• What are variables?


  A variable is something that may vary or change within an investigation.
• When is a variable used in an investigation?


  To determine if changing one thing will have an affect on another thing.
• What are the two types of variables?

  Independent and dependent.
• What is an independent variable?


  The independent variable (IV) is the variable that is manipulated or changed in an experiment.
• What is the dependent variable?


  The dependent variable (DV) is the variable that is being measured by the researcher in an experiment.
• What is the relationship between the IV and the DV?


  The IV is changed to see how it will affect the DV.
• Why should all variables but the IV remain constant?


  To isolate the effect of the independent variable, giving the experiment internal validity.
• What do experimental conditions allow us to do?


  Test the aim towards the hypothesis.
• What are the two ways we can test the effect of the IV on the DV?


  Comparing the DV before and after changing the IV, or comparing two groups-- one with the IV manipulated one way, and another with the IV manipulated a different way.
• What is the experimental condition?


  The independent variable which has been manipulated.
• What is the control condition?


  The baseline condition of the participants.
• What is operationalisation?


  The process of clearly defining and in terms of how they can be measured.
• What does operationalisation involve?


  Including measurements or what the researcher is specifically testing for within the hypothesis.