AICE Psychology

Research methods notecards

Experiment

An investigation that allows researchers to look for a casual relationship; an independent variable is manipulated and is expected to be responsible for changes in the dependent variable.

Independent variable

the factor under investigation in an experiment that is manipulated to create two or more conditions and is expected to be responsible for changes in the dependent variable

dependent variable

the factor in an experiment that is measured and is expected to change under the influence of the independent variable

uncontrolled variable

a variable that either acts randomly affecting the DV in all levels of the IV or systemically

experimental condition

one or more of the situations in an experiment that represent different levels of the IV and are compared

control condition

a level of the IV in an experiment from which the IV itself is absent. It is compared to on for more experimental conditions

experimental design

the way in which participants are allocated to levels of the IV

Independent measures design

an experimental design in which a different group of participants is used for each level of the IV

demand characteristics

features of the experimental situation which give away the aims

random allocation

a way to reduce the effect of confounding variables such as individuals differences

repeated measures design

an experiment design in which each participant performs in every level of the IV

participant variables

Individual differences between participants that could affect their behavior in a study that would hide or exaggerate differences between levels of the IV

confounding variables

an uncontrolled variable that acts systemically on one level of the IV so could hide or exaggerate differences between levels and therefore confound or confuse the results making it difficult to understand the effect of the IV on the DV

order effects

Practice and fatigue effects are the consequences of participating in a study more than once, for example in a repeated measures design.

practice task

a situation where participants performance improves because they experience the experimental task more than once, for example due to familiarity or learning the task

fatigue effect

a situation where participants performance declines because they experience the experimental task more than once.

randomisation

a way to overcome order effects in a repeated measures design.

counterbalancing

a way to overcome order effects in a repeated measure design

matched pairs design

an experimental design in which participants are arranged into pairs

laboratory experiment

a research method in which there is an IV, a DV and strict controls

controls

ways to keep potential confounding variables constant, for example between levels of the IV, to ensure measured differences in the DV are likely to be due to the IV, raising validity

standardization

keeping the procedure for each participant in a study exactly the same to ensure that any difference between participants or conditions are due to the variable under investigation rather than differences in the way they were treated

reliability

the extent to which a procedure, task or measure is consistent, for example that it would produce the same results with the same people on each occasion

validity

the extent to which the researcher is testing what they claim to be testing

pilot study

a small-scale test of the procedure of a study before the main study is conducted. It aims to ensure that the procedure and materials are valid and reliable so that they can be adapted if not

replication

keeping the procedure and materials exactly the same between studies when attempting

operational definition

the clear description of a variable such that it can be accurately manipulated, measured or quantified, and the study can be replicated

placebo

a pill or procedure given to a patient who believes it to be a real treatment which in fact has no active ingredient

field experiment