Pyschological Investigations (Defs) Flashcards
Participants
People who take part (participates) in a research investigation.
Experiment
A study where an independent variable is manipulated, the dependent variable is measured and other variables are controlled.
Variables
The things we measure, control or manipulate in an experiment.
Independent Variable
Variable that the experimenter manipulates in an experiment and is assumed to have direct effect on the DV.
Dependent Variable
Variable that the experimenter measures and assumed to be directly affected by changes in the independent variable.
Aim
A general statement about the purpose of the investigation.
Hypothesis
A precise, testable statement about the expected outcome of the experiment.
Alternate Hypothesis
A hypothesis that predicts there will be an effect of the IV on the DV.
Null Hypothesis
A hypothesis that predicts that there will be no effect of the IV on the DV.
Two-tailed hypothesis
A hypothesis that states there will be a difference but does not specify how the IV will affect the DV. (Don’t know how the results will end up). E.g. There will be a difference in the number of words recalled in the reading aloud condition compared to the not reading out loud condition.
One-tailed hypothesis
A hypothesis that states there will be a difference and is specific about how the IV will affect the DV (predicts the direction of the results.) e.g. People who drink alcohol will take longer to stop the car than those who didn’t drink alcohol.
Operationalising
Defining your variables clearly so that you can manipulate or measure them.
Extraneous Variables (EV)
Anything other than the IV that could affect the DV.
EV- Participant Variables
Ways in which the population vary (age, gender, motivation) that can have an effect on the DV.
EV- Situational Variables
External influences on behaviour.
