Variables: a crash course Flashcards
IV
- the variable that you change/ control, i.e. manipulate
- assumed to have a DIRECT EFFECT on the DV
DV
- variable being tested & measured
- outcome/ results of the study
- “dependent” on the IV
what is a researcher looking for in an experiment?
a possible effect on the DV that might be caused by manipulating the IV
What are operational variables aka?
Operationalising definitions
what does operationalisation refer to?
how you will DEFINE & MEASURE a specific variable as it’s used in the study
v. important to CLEARLY DEFINE what you mean by BOTH you IV & DV- otherwise it’d be impossible to COMPARE findings of different studies into the same behaviour
pro of operationalisation
provides a clear & objective definition of even complex variables- EASIER for replication & to check for reliability
EVs
are all variables, excluding the IV, which could impact the results of an experiment
researcher wants to ENSURE that it’s the manipulation of the IV that has caused the changes in the DV, so ALL the other variables that could affect the DV must be controlled
EVs must be controlled because>
they might be important enough to provide alternative explanations for the effects
the 4 types of EVs are?
- situational variables
- participant variables
- experimenter/ investigator effects
- DCs
what are situational variables?
these are aspects of the ENVIRONMENT that might affect the PP’s behaviour:
- noise
- temp
- lighting conditions, etc
how to CONTROL SVs?
standardised procedures must be used to ensure that the conditions are the SAME for all participants, including the use of standardised instructions
Participant variables
- refers to the ways in which EACH PP VARIES from the other, and how this could affect the results
- ex: if a PP that performed a memory test was tired/ dyslexic, this could affect their performance & results
The ED chosen can have an affect on…
PVs
situational variables also include
order effects that can be controlled using COUNTERBALANCING
PVs can be controlled using?
random allocation to each condition of the IV
what are investigator effects?
- whereby he unconsciously conveys to PPs HOW they should behave: this is called EXPERIMENTER BIAS
- they might do this by giving UNINTENTIONAL CLUES to the PPs about:
1) what the experiment is ABOUT
2) how they EXPECT them to behave - he is often unaware of this and the cues may be v subtle but they’ve an influence nonetheless
- also their personal attributes can have an impact
DCs
these are all the CLUES in an experiment which convey to the PP the PURPOSE of the research
PPs will be affected by their:
1) surroundings
2) researcher’s characteristics & behaviour
3) interpretation of what’s occurring
they should try to MINIMISE these factors by keeping the experiment as NATURAL as poss- carefully using standardised procedures
perhaps DIFFERENT EXPERIMENTERS should be used to see if they obtain SIMILAR results
