Experimental Methods

• Experimental Method


  Involves the manipulation of an independent variable to measure the effect on the dependent variable. Experiments may be laboratory, field, natural or quasi.
• Aim


  A general statement of what the researcher intends to investigate, the purpose of the study
• Hypothesis

  A clear, precise, testable statement that states the relationship between the variables to be investigated. Stated at the outset of the study
• Directional hypothesis


  States the direction of the difference or relationship
• Non-directional hypothesis


  Does not state the direction of the difference or relationship
• Variables


  factors that can change in an experiment
• independent variable


  The experimental factor that is manipulated; the variable whose effect is being studied.
• Dependent variable


  The variable that is measured by the researcher
• Operationalism


  Clearly defining variables in terms of how they can be measured
• How do researchers decide what type of hypothesis to use?


  Directional hypothesis- a theory or findings from a previous research study suggest a particular outcome

  Non-directional hypothesis- there is no previous research, or previous findings are contradictory