Participants are randomly allocated to different conditions and then their results are compared
A study in which there is an independent variable but this cannot be manipulated by the researcher, as the groups are naturally occurring. E.g. The independent variable could be gender or country of birth. Can be conducted in a lab or natural setting.
Characteristics that may vary from participant to participant and can impact upon results, e.g. IQ or preferences.
Variables which are kept constant to ensure only the independent variable has an effect on the dependent variable.
How participants are allocated to the different conditions in the experiment.
A testable statement.
A study involving manipulation of an independent variable, conducted in a natural setting.
The variable in the experiment that is deliberately and systematically manipulated so that its effects on the DV can be observed and measured.
A constant and unchanging standard of comparison within the study.
The factor that is affected by the manipulation of the IV. It is the outcome measure in an experiment.
Differences in participants' responses that have occurred due to the sequence in which the experimental materials/conditions are presented to them. E.g. practice effects improving results or fatigue/boredom affecting results negatively.
An element or factor that is liable to change/can be changed
Participants are matched on the basis of key characteristics relevant to the research question, then the pairs are split into groups, with one participant from each pair being placed into each condition.
A study in which there is an independent variable but this is not manipulated by the researcher - it occurs naturally. Conducted in a natural/everyday setting.
Keeping everything in an experiment the same for every participant to ensure the investigation is valid.
All participants take part in all conditions and then their results are compared.
An experimental control. All possible orders of undertaking the conditions are included (e.g. ABBA), to prevent order effects, such as practice or fatigue.
Individuals taking part in a study.
Dividing participants into the experimental conditions in a way that results in every member of the population having an equal chance of being selected. E.g. the lottery method.
A study involving manipulation of an independent variable, conducted under tightly controlled conditions.