Experimental Method Flashcards
What is the experimental method?
A method which involves manipulating an IV to measure the effect on the DV
Define ‘aim’
Describes the purpose of a study
Define ‘hypothesis’
Clear, precise, testable statement that states the relationship between two variables
e.g. leaving for lunch will effect GCSE results
What is a directional hypothesis? When is it used?
Shows expected direction of the relationship between two variables.
When there has been prior research to indicate a direction of the relationship.
e.g. leaving for lunch will increase GCSE results
What is a non-directional hypothesis? When is it used?
Outlines a relationship between two variables but doesn’t state the expected direction of the relationship.
When research is conflicting or there has been no prior research.
e.g. leaving for lunch will effect GCSE results
What does it mean to operationalise a variable?
Clearly defining variables to make them specific and clearly measurable
Define ‘independent variable’
The variable that is manipulated by the researcher
Define ‘dependent variable’
The variable that is measured by the researcher
What are extraneous variables?
The variable (other than the IV) that potentially affects the DV in a non-systematic way. Can be controlled. May compete with the IV.
What are confounding variables?
The variable (other than the IV) that will affect the DV in a systematic way so we can’t tell if a change in the DV is due to manipulation of the IV or a confounding variable.
What are participant variables? Examples
Type of extraneous variables related to the individual differences between participants which may affect the DV e.g. IQ, Age, Gender
What are situational variables? Examples
Type of extraneous variables relate to the differences in the environment of the experimental situation which may affect the DV e.g. Temperature, time of day, weather, noise.
What are demand characteristics?
Cues from the experiment allowing the participant to work out the purpose of the experiment
What are investigator effects?
Unconscious or conscious effect of the investigator on the DV.
E.g. smiling at participants giving correct answers or asking leading questions.
What is randomisation?
Use of chance to reduce the researcher’s influence on the investigation.
E.g. order of word lists are random. Controls for investigator effects.
What is standardisation?
Using exactly the same formalised procedures and instructions for all participants in a research study. Controls for situational variables.
What is a single-blind procedure and what is it’s purpose?
When participants are not aware of the aim of the study or which condition they are in in the experiment. To control for demand characteristics.
What is a double-blind procedure? What is the purpose?
When both the participants and experimenter are not aware of the aim of the experiment. To reduce demand characteristics and investigator effects.
What is a pilot study?
A small-scale trial run that takes place before the actual investigation is conducted.
What is the purpose of a pilot study?
To check that procedures, materials, measuring scales etc. work and to allow researcher to make changes or modifications
