Variables Flashcards
Define an independent variable
Variable that the research manipulates
e.g skirt length
What is the main characteristic of an experiment?
IV can be delibrately changed to see if it has any effect on the DV
this is in order to draw conclusion and establish cause and effect
IV affects DV
Define dependent variable
Variable the researcher will measure
This shown to be a change in IV
e.g Davy’s heart rate
Define extraneous variable
Variables that could affect the IV or DV
e.g other appearances like glasses
Define confounding variable
Variable that has effect the results
e.g Connie having a gun
Psychology research:
Loftus carried out research to study the weapon effect and how anxiety can affect the accuracy of eyewitness testimony
Identify IV and specify how it was manipulated
Loftus manipulates two conditions
Knife and Pen
Psychology research:
Loftus carried out research to study the weapon effect and how anxiety can affect the accuracy of eyewitness testimony
Identify DV and specify how it was measured
Measuring the accuracy of eyewitness or recall
Psychology research:
Loftus carried out research to study the weapon effect and how anxiety can affect the accuracy of eyewitness testimony
Identify any extraneous variables
Participant having mental illness or blind
Explain independent ,dependent , confounding and extraneous variables
Ivy , Davey , Evie , Connie
- Ivy wears short top
- Ivy wears long dress on second day
- Davey heart rate measured on day 1 and compared with day 2
- Evie is there with glasses
- Connie comes up with a gun
In order to study the effects of sleep deprivation students are asked to limit their sleep to five hours a night for 3 nights and then sleep normally the next night
Each day student’s cognitive ability is assessed using a memory test
Identifiy IV , DV and EV
IV: Would be the hours of sleep
DV: Cognitive ability by memory test results
EV: IQ or Quality of sleep , drugs
Participant volunteer to take part in the study
They are told the study is about public speaking but the real aim is to see how people respond to encouragement by others
Some participants speak in front of a group of people who smile at them, while others talk to a group who seem disinterested
Identify IV , DV and EV
IV: Crowd, smile or disinterested
DV: How people respond (operationalized - body language)
EV: Deaf , Confidence of speaker , Experience
Marathon runners are assessed on how much sleep they have the night before and the night after a race to see what the effects of exercise are on sleep
Identifiy IV , DV and EV
- IV: Before and after race hours of sleep
- DV: Hours of sleep on effect of exercise
- EV: Anxiety , Distress , Gender
A teacher is doing a psychology course and decides to try a little experiment with her class of 8-year-olds. She gives half the class a test in the morning and a half to do the same test in the afternoon to see if the time of day affects their performance
Identify IV , DV and EV
- IV: Time of day when test comes (operationalised - morning or afternoon)
- DV: Performance on test
- EV: Learning disability , Anxiety , food , sleep
What is opertionalise?
Process of ensuring variables are in a form that can be easily tested and specifically defined in order to fully understood
What happens if variables are not operationalised?
Will not know what they are looking for and reduce validity and reliability of their data
