Experimental control Flashcards
What is a confounding variable?
to confound means to cause Confusion. A variable that is not the independent variable but which varies systematically with the IV. Changes in the dependent variable may be due to the confounding variable rather than the IV and therefore the outcome is meaningless….
What is another word for confounding variable?
An extraneous variable
What are order effects
Order effects are an extraneous variable
What are participants variables?
Participants in one group may be different to the participants in other groups in importance ways e.g. personal characteristics such as intelligence can become an alternative Iv and be confounding
What are situational variables?
Factors in the environment that could act as an extraneous variable such as noise time of day or the behaviour of an investigator
What are investigator effects
The behaviour of the investigator may affect participants and this affected the DV?
What does control mean?
Control means making thing change and keeping things constant - Experimenter needs to control the Cvs and the IV
What is counterbalancing
An experimental technique designed to overcome order effects… It ensures that each condition is tested first or second in equal amounts
How can participants variables be controlled
By randomly allocating participants to groups in an independent groups designed or using a matched pair’s design or a repeated measures design
How can situational variables be controlled?
By using standardised procedures
What are standardised instructions
This refers to common instructions that are given to all participant at the beginning of the study
How can investor effects be dealt with?
By using a double blind design
What is a double blind design
This is when both the participant and the person conducting the experiment don’t know the aims
