Methodology: Variables and Types of Bias Flashcards
What are the 3 main types of variables?
1) Independent variable
2) Dependent variable
3) Extraneous variable
Define ‘operationalisation’.
Variables must be fully operationalised, especially the dependent variable in order to be made measurable.
Define ‘independent variable’.
The variable that the experimenter manipulates to demonstrate a difference between the experimental conditions.
Give an example of an independent variable used in cognitive psychology.
Baddeley’s (1966) acoustic similarity and semantic similarity word lists.
Evaluate the reliability of independent variables using a high point.
P - High test-retest
E - Manipulation of the IV creates a standardised procedure
E - Therefore the experiment will be easy to replicate to test for consistency
Evaluate the validity of independent variables using a high and low point.
P - High
E - Having an IV coincides with a DV
E - Can therefore establish cause and effect relationship
P - Low
E - Manipulation conditions of an experiment usually creates artificial settings
E - Therefore it wouldn’t be natural to ppts and so they wouldn’t exhibit behaviour that reflects real life
Define ‘dependent variable’.
The variable that the experimenter measures to see if the change in IV has created a different effect.
Give an example of a dependent variable used in cognitive psychology.
Baddeley’s (1966) number of words from a list recalled correctly.
Evaluate the reliability of dependent variables using a low point.
P - Low
E - Sometimes variables may not be fully operationalised
E - Therefore they can be hard to measure and compare
Evaluate the validity of dependent variables using a high and low point.
P - High
E - Having an IV coincides with a DV
E - Can therefore establish cause and effect relationship
P - Low
E - Operationalisation and measurement of variables may lead to researcher bias as they will be looking for specific things
E - Therefore can impact credibility with subjective findings
Define ‘extraneous variable’.
The variables that aren’t the IV or DV.
Define ‘confounding variable’.
An EV that is important enough to provide an alternative explanation for the effects on the DV.
What are the 2 types of extraneous variables?
1) Situational
2) Participant
Define ‘situational variable’.
Variables from the environment.
Give an example of a situational variable.
Weather
Define ‘participant variable’.
Variables that create differences in the sample due to ppts individual characteristics.
Give an example of a participant variable.
Gender
Evaluate the reliability of extraneous variables using a low point.
P - Low test-retest
E - They can make conditions hard to standardise or measure in any one given way
E - Therefore conditions will be hard to replicate to test for consistency
Evaluate the validity of extraneous variables using a low point.
P - Low
E - They can interfere with the relationship between the IV and DV
E - Therefore limiting the cause and effect relationship that can be established
Define ‘demand characteristics’.
Behaviours of ppts that results in cues from the aim of the environment of the experiment that suggest they should behave a certain way.
Evaluate the validity of demand characteristics using a low point.
P - Low
E - Ppts often try to guess the aim and so behave in a way they think the experimenter would want them to or not want them to
E - Therefore behaviour will not reflect behaviour in real life due to this bias
Define ‘experimenter effect’.
When aspects of the researcher can lead ppts to think they should act a certain way.
Give an example of an experimenter effect in psychology.
Their appearance/behaviour.
Define ‘researcher bias’.
When a researcher influences the results in order to achieve a certain outcome.
Give an example of researcher bias in psychology.
Discarding results that reject the hypothesis of the experiment.
Define ‘single blind procedure’.
When ppts don’t know the true aim of the study.
Define ‘double blind procedure’.
When ppts and the researcher don’t know the true aim of the study.
How do single/double blind procedures remove bias?
Single blind - it removes DCs from ppts as they are unaware of the aim so would behave normally as wouldn’t know otherwise
Double blind - it removes DCs and researcher bias as they wouldn’t know what data to change/discard to fit the hypothesis
