Research Methods EXTRANEOUS VARIABLES The variable that is

Research Methods

EXTRANEOUS VARIABLES The variable that is measured and is assumed to be a direct result of changes made by experimenters INDEPENDENT VARIABLE (IV) Predicts the direction in which any differences in the results of an investigation are expected to occur DEPENDENT VARIABLE (DV) The narrowing down of the research focus so that factors become measurable and observable ONE-TAILED (DIRECTIONAL) HYPOTHESIS Does not predict the direction in which any differences in the results of an investigation are expected to occur TWO-TAILED (NON-DIRECTIONAL) HYPOTHESIS OPERATIONALISING VARIABLES The variable manipulated/controlled by the experimenter Anything other than the IV which could affect the DV

� Define three experimental designs � Identify strengths and weaknesses of each experimental design � Recognise which experimental design is being used for given experiments

� In - your groups/pairs: Come up with a definition/description of your design Use the spinach/muscle strength study to show an example of your design Identify the strengths and weaknesses of your design

� Complete the task to identify which definition, strengths and weaknesses goes with each design � Distinguish between the 3 with different colours

� Which experimental design is being used in the example experiments?

� Design an experiment using the different design methods given � How could the study be adapted for different designs?

� Define three experimental designs � Identify strengths and weaknesses of each experimental design � Recognise which experimental design is being used for given experiments