experimental methods

• what is a theory?

  initial general ideas about a topic before they narrow the focus into an aim (a starting point)
• what is an aim?

  a statement of what the researcher intends to investigate developed from theories, that always start with 'to investigate...'
• what is a hypothesis?

  a precise, testable statement of what the researcher predicts will be the outcome of the study, that states the relationship between the variables to be investigated
• what is a directional hypothesis?

  predicts which direction the change will take place, that is used when the findings of previous research studies suggest a particular outcome
• what is a non-directional hypothesis?

  just states that there will be a difference and not what it will be, that is used when there is no previous research or when earlier findings are contradictory
• what is a null hypothesis?

  predicts that a statistically significant effect will not be found, or any results found will be due to chance
• what is the independent variable?

  some aspect of the experimental situation that is manipulated by the researcher, or changes naturally, so the effect on the dependent variable can be measured
• what is the dependent variable?

  the variable that is measured by the researcher, that should change because of a change in the independent variable
• what is a causal (cause and effect) relationship?

  when changes in the independent variable directly lead to changes in the dependent variable
• what is the experimental condition?

  the variable that is manipulated in order to see an effect
• what is the control condition?

  the condition that isn't manipulated so that you have a baseline to compare results with