Chapter 3 Experiments and Experimental Designs Flashcards Preview

Research Methods And Statistics In Psychology > Chapter 3 Experiments and Experimental Designs > Flashcards

Flashcards in Chapter 3 Experiments and Experimental Designs Deck (25)
Loading flashcards...

Asymmetrical Order Effect

Order effect that has greater strength in one particular order of conditions and where, therefore, counterbalancing would be ineffective


Baseline Measure

Measure of what would occur if not experimental level of the independent variable 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

Group used as a baseline measure against which the performance of the experimental group is assessed



Half of the participants do conditions in a particular order and the other half take the conditions in the opposite order - this is done to balance possible order effects


Dependent Variable (DV)

Variable that is assumed to be directly affected by changes in the independent variable in an experiment



Design in which an independent variable is manipulated, all other variables controlled and a dependent variable is measure for changes caused by the independent variable


Factorial Design

Experiment in which more than one independent variable is manipulated


Independent Samples Design (independent groups/measures; between groups/subjects)

Each condition of the independent variables is experience by only one group of participants


Matched Pairs Design

Each participant in one group/condition is paired on specific variable(s) 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 Design(within subjects/groups)

Each participant experiences all levels of the independent variable


Single Participant Design

Design in which only one participant is tested in several trials at all independent variable levels


Small N Design

Design in which there is only a small number of participants, typically in clinical or counselling work but also where participants need substantial training for a highly skilled task


Unrelated Design

Design in which individual scores in one condition cannot be paired (or linked) in any way with individual scores in any other 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 (IV)

Variable which experimenter manipulates in an experiment and which is assumed to have a direct effect on the dependent variable


Levels (of the IV)

The different values taken by the independent variable; often, the conditions of an experiment, e.g., levels of caffeine at 50mg, 100mg and 200mg in the investigation of memory recall


Non-Equivalent Groups

A possible confounding variable where two or more groups in an independent samples design experiment differ on a skill or characteristic relevant to the dependent variable


Order Effect

A confounding effect caused by experiencing one condition, then another, such as practice or fatigue


Placebo Group

Group of participants who don't receive the critical 'treatment' but everything else the experimental group receives; used in order to eliminate placebo effects - participants may perform differently simply because they think they have received an effective treatment



Measure of participants before an experiment in order to balance or compare groups, or to assess change by comparison with scores after the experiment



Putting stimulus items or trial types into random order for the purpose of elimination of order effects


Standardised (procedure)

Testing or measuring behaviour with exactly the same formalised routine for all participants



A story, scenario, or other description given to all participants but with certain details altered and this difference constitutes the random variable