3-EXPERIMENTS AND EXPERIMENTAL DESIGN Flashcards
(25 cards)
Asymmetrical order effect
Order effect that has a greater strength in one particular order of conditions and where, therefore counterbalancing would be ineffective
Baseline measure
What would occur if no experimental level of the independent measure were applied; how ‘untreated’ participants perform.
Confounding variable
Variable that is uncontrolled and obscures the effect sought, varying with the independent variable in a systematic manner.
Control group
Used as a baseline measure against which the performance of the experimental group is assessed.
Counterbalancing
Half of the participants do conditions in a particular order and the older half take the conditions in the opposite order-this abalones the possible effects.
Dependent variable
Assumed to be directly affected nu changes in the independent variable in an experiment.
Experiment
Design in which an independent variable is manipulated, all other variables controlled and dependent variable is measured for changes caused by the independent variable.
Factorial design
More than one independent variable is maintained.
Independent samples (measures)
Each condition of the independent variable is experiences by only one group of participants.
Matched pairs
Each participant in one group/ condition is paired on specific variables with a participant in another group/ condition.
Related design
Design in which individual scores in one condition can be paired with individual scores in other conditions (repeated measures and matched pairs).
Repeated measures
Each participant experiences al levels of the independent variable.
Single participant
Design in which only one participant is tested in several trials at all independent variable levels.
Small N design
There is only s small number of participants, typically in clinical or counselling work but also where participants need substantial training for a highly skilled task.
Unrelated design
Individual scores none condition cannot be paired or linked I any way with individual scores in another condition.
Extraneous variable
Anything other than the independent variable that could affect the dependent variable; it may or may not have been allowed for and/or controlled.
Independent variable
Manipulated by the experimenter which is assumed t have a direct effect on the dependent variable.
Levels of the IV
Different values taken by the independent variable; often, the conditions of an experiment.
Non-equivalent groups
A possible confounding variable where two or more groups in an independent measures differ on a skill pr characteristic relevant to the dependent variable.
Order effect
A confounding effect caused by experiencing one condition, then another, such as practice of fatigue.
Placebo group
Group who don’t receive the critical ‘treatment’ but everything else the experimental group receives; used in order to eliminate places effects.
Pre-test
Measure of participants before an experiment in order to balance or compare groups, r to assess change by comparison with scores after the experiment.
Randomisation
Putting stimulus items or trial types into random order for the purpose of elimination of order effects.
Standardisation
Using the exact same formalised routine for all participants.
