#1
Which of the following is a key component of experimental design?
Random assignment
ExplanationAssigning subjects to different groups randomly to minimize bias.
#2
What is the primary purpose of the Institutional Review Board (IRB) in experimental research?
To ensure ethical treatment of human subjects
ExplanationProtecting participants' rights and welfare.
#3
What is the purpose of a control group in an experiment?
To provide a baseline for comparison
ExplanationTo have a group unaffected by the experimental treatment for comparison.
#4
Which statistical test is appropriate for comparing means of two independent groups?
Independent samples t-test
ExplanationUsed to compare means from two different groups.
#5
In a factorial design, what does a 2x3 design represent?
Two independent variables with a total of three levels
ExplanationTwo factors with 2 and 3 levels respectively.
#6
Which type of probability sampling method involves selecting every kth element from a list?
Systematic sampling
ExplanationSelecting samples at fixed intervals.
#7
Which of the following is a non-parametric statistical test for comparing two independent samples?
Mann-Whitney U test
ExplanationUsed when data does not meet parametric assumptions.
#8
What does p-value signify in hypothesis testing?
Probability of Type I error
ExplanationThe likelihood of rejecting a true null hypothesis.
#9
What is the purpose of randomization in experimental design?
To reduce selection bias
ExplanationTo ensure all groups have equal chances of being assigned.
#10
What is the purpose of blocking in experimental design?
To control for extraneous variables
ExplanationMinimize variation due to external factors.
#11
What does the term 'statistical power' refer to in hypothesis testing?
The probability of rejecting a false null hypothesis
ExplanationThe ability to detect real effects.
#12
What is the purpose of a pilot study in experimental research?
To identify and address potential issues with the study design
ExplanationTo refine experimental procedures before full-scale implementation.