Lesson 3.1.4.6.2

3.1.4.6.2 Extraneous variables and how to control for them Quiz: AQA Psychology, Unit 4

20 questions

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Lesson 3.1.4.6.2, Extraneous variables and how to control for them: 20 multiple choice questions for the AQA GCSE Psychology (8182), Unit 4: Research methods, written with Revision Ninja.

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The 20 questions

  1. What is an extraneous variable?

    • A variable other than the independent variable that could affect the dependent variable
    • The measure recorded at the end of each trial
    • The group of participants who receive no treatment at all
    • The variable that the researcher deliberately changes between conditions

  2. A memory study varies the length of the word list (the independent variable) and counts the words recalled (the dependent variable). Which of these is an extraneous variable?

    • The length of the word list given to each group
    • Background noise changing between testing sessions
    • The delay between learning and recall set by the researcher
    • The number of words correctly recalled by each participant

  3. Which is a way to control extraneous variables in the testing environment?

    • Allowing each participant to choose the room they prefer
    • Changing the instructions depending on the mood of the participant
    • Testing participants in different rooms to add variety
    • Testing all participants in the same room at the same time of day

  4. Why does random allocation help control extraneous variables?

    • It ensures each participant scores the same on the dependent variable
    • It guarantees that extraneous variables have no effect at all
    • It removes all differences between participants from the study
    • It spreads participant differences evenly across conditions by chance

  5. Which extraneous variable does counterbalancing help control?

    • The number of questions in the final test, which can change how hard the test feels
    • Order effects, such as practice or fatigue, across repeated conditions
    • The gender of the researcher who runs the session, and how participants respond to them
    • The age of participants in the sample, which can change how they perform tasks

  6. A study tests reaction time at 9 am and 4 pm for all participants. What extraneous variable is possible?

    • The independent variable chosen by the researcher
    • The number of reaction trials recorded
    • The dependent measure of reaction time in milliseconds
    • Time of day affecting alertness and reaction speed

  7. A researcher tests one group in a noisy corridor and another in a quiet room. What is the problem?

    • A matched pairs design with identical groups of participants in each room
    • An uncontrolled extraneous variable that may affect the results
    • A successful use of standardised instructions for both groups
    • A correct use of counterbalancing to spread the order of conditions evenly

  8. Which is a sensible control for the effect of participant fatigue in a long experiment?

    • Telling participants to work as quickly as possible
    • Giving rest breaks and counterbalancing the order of conditions
    • Making the task longer so participants become used to it
    • Testing only the first half of the participants

  9. What is the purpose of controlling extraneous variables?

    • So that participants can be told the hypothesis before they begin the study
    • So that the sample size can be reduced without losing validity or statistical power
    • So that the researcher can choose which participants to include in each condition
    • So that any change in the dependent variable can be attributed to the independent variable

  10. In a study on revision methods, one group had less sleep the night before. What is this?

    • The dependent variable measured by exam scores
    • A control condition that improves the validity of the findings
    • The independent variable that the study intended to test
    • An extraneous variable that could confound the findings

  11. Which step best controls participant variables in an independent groups design?

    • Using the same participants for every condition in the study to avoid any individual differences
    • Matching participants on relevant characteristics before allocating them to groups
    • Letting participants pick their own group for comfort and to make them feel more relaxed
    • Excluding any participants who differ in age from the rest of the sample before testing

  12. A researcher tells every participant the study's hypothesis before testing. What does this risk?

    • Demand characteristics that could change how participants behave
    • A matched pairs design with fewer participants but more time for each session
    • Counterbalancing of the order of conditions across all of the participants tested
    • Random allocation of participants to each of the conditions in the study

  13. A researcher uses a stopwatch, but different experimenters time different groups. Which extraneous variable is this?

    • Experimenter differences in timing that may affect results
    • The independent variable of time pressure
    • A standardised instruction used for all participants
    • The dependent variable of task completion

  14. A study compares two classrooms, one with better lighting. Why is this a problem?

    • Lighting makes the sample representative of all schools
    • Lighting is the independent variable the study was designed to test
    • Lighting is an uncontrolled extraneous variable that could explain the difference
    • Lighting is a standard procedure that improves reliability

  15. Why can extraneous variables reduce the validity of an experiment?

    • They make the study qualitative rather than quantitative, so results cannot be compared
    • They can cause changes in the dependent variable that are not caused by the independent variable
    • They prevent researchers from using any statistical test on the data collected
    • They reduce the number of participants needed for a valid result in most experiments

  16. Which control is most effective for a participant variable such as intelligence in an independent groups design?

    • Asking participants to self-report their intelligence on a form
    • Excluding participants who score above average on the intelligence test
    • Matching participants on intelligence scores before random allocation
    • Ignoring intelligence because it is unrelated to the dependent variable

  17. Which statement correctly evaluates the control of extraneous variables in a lab study?

    • Strict control removes all errors and makes results fully generalisable
    • Strict control is not needed when the sample is random
    • Strict control only matters for qualitative studies
    • Strict control improves internal validity

  18. Which way controls the influence of the experimenter's behaviour?

    • Letting each experimenter adapt the script to suit the mood of the participant
    • Changing the experimenter halfway through each testing session
    • Using a standard script and training experimenters to behave the same way
    • Having participants run their own sessions without supervision

  19. A researcher uses matched pairs but cannot match participants on every relevant variable. What is the best evaluation?

    • Some extraneous variables may remain uncontrolled
    • Unmatched variables do not affect results in an experiment
    • The study must be discarded because matched pairs are impossible
    • Matched pairs always remove every extraneous variable completely

  20. Why are counterbalancing and randomisation both used in a repeated measures study?

    • Randomisation is used only when there is one participant in the study
    • Counterbalancing controls order effects
    • Counterbalancing replaces randomisation so both are never needed together
    • Both control only the independent variable, so they duplicate each other

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