#1
In experimental design, what is the purpose of a control group?
To provide a baseline for comparison
ExplanationEstablishes a reference point to assess the effect of the independent variable.
#2
What is the primary purpose of a pilot study in experimental research?
To gather preliminary data
ExplanationTests feasibility and identifies potential issues before the main study.
#3
Which of the following is a key component of statistical sampling?
Randomization
ExplanationEnsures each element in the population has an equal chance of being selected.
#4
Which statistical sampling method involves dividing the population into subgroups and then randomly selecting samples from each subgroup?
Stratified random sampling
ExplanationEnsures representation from different subgroups for more accurate results.
#5
In statistical sampling, what does the term 'confidence level' represent?
The likelihood of obtaining a sample statistic within a certain range
ExplanationExpresses the degree of confidence that the sample parameter falls within a specified interval.
#6
Which type of experimental design involves studying the same group of participants over an extended period of time?
Longitudinal design
ExplanationTracks changes in participants over time for a comprehensive understanding.
#7
In statistical sampling, what is the purpose of stratification?
To reduce variability within subgroups
ExplanationIncreases precision by accounting for variations within distinct population subsets.
#8
Which of the following is an advantage of using systematic sampling in statistical research?
Reduced sampling bias
ExplanationMinimizes bias by selecting samples at regular intervals, providing a representative sample.
#9
What is the term for the systematic error in sampling that occurs when the sample is not representative of the population?
Bias
ExplanationResults in a consistent deviation from the true population value.
#10
What is the purpose of blinding in experimental design?
To eliminate biases
ExplanationPrevents participants or researchers from influencing the results consciously or unconsciously.
#11
What is the main advantage of using a completely randomized design in experiments?
Reduced chance of sampling bias
ExplanationMinimizes the likelihood of favoring a specific group during the assignment process.
#12
What is the term for the extent to which an experiment measures what it is intended to measure?
Validity
ExplanationReflects the accuracy and relevance of the experiment in assessing the intended variables.
#13
In statistical sampling, what is the difference between simple random sampling and systematic sampling?
The order of selection
ExplanationSimple random sampling is entirely random, while systematic sampling follows a predetermined pattern.
#14
What is the purpose of statistical power analysis in experimental design?
To determine sample size
ExplanationCalculates the required sample size to detect a significant effect.