#1
Which of the following is a threat to internal validity in experimental design?
Maturation
ExplanationEffects caused by natural processes, like aging, that can influence study outcomes.
#2
What is the primary purpose of random assignment in experimental design?
To ensure all groups are equivalent at the start of the study
ExplanationMinimizing pre-existing differences between groups to isolate the treatment effect.
#3
What is the purpose of using a control group in an experiment?
To provide a comparison for the experimental group
ExplanationCreating a baseline for comparison to assess the true impact of the experimental treatment.
#4
How can random selection of participants enhance the internal validity of an experiment?
By ensuring that all participants have an equal chance of being assigned to each group
ExplanationReducing selection bias by giving every potential participant an equal opportunity to be part of the study.
#5
In experimental design, what does the term 'history' refer to?
External events affecting the outcome
ExplanationExternal events occurring during the study that may impact the results.
#6
What is a potential way to mitigate the threat of 'testing' in an experimental study?
Implementing a crossover design
ExplanationUsing different sequences of conditions to minimize the impact of repeated testing.
#7
Which of the following is a characteristic of a true experimental design?
Random assignment
ExplanationAssigning participants randomly to experimental and control groups to ensure group equivalence.
#8
Which of the following best describes the threat of 'mortality' in experimental design?
Loss of participants from the study over time
ExplanationParticipants dropping out or no longer being available, leading to biased results.
#9
Which of the following is an example of a potential confounding variable in an experiment investigating the effects of a new medication?
The gender of the participants
ExplanationAn external factor that may impact the dependent variable and cloud the true treatment effect.
#10
Which of the following is a potential solution to the threat of 'instrumentation' in experimental design?
Implementing a double-blind procedure
ExplanationKeeping both participants and researchers unaware of the treatment conditions to prevent bias in data collection.
#11
How can researcher bias affect internal validity in an experiment?
By affecting the measurement process
ExplanationResearcher's preconceived notions influencing data collection or interpretation.
#12
How does the placebo effect relate to internal validity in experimental design?
It can confound the results by influencing participant behavior
ExplanationParticipants' responses influenced by the belief that they are receiving a treatment, impacting the study's outcome.