#1
In statistical terms, what does 'mean' refer to?
The middle value in a dataset
The sum of all values divided by the number of values
The most frequently occurring value
The range of values in a dataset
#2
What is the purpose of correlation analysis in statistics?
To determine causation between variables
To identify relationships and measure the strength and direction of linear associations between variables
To calculate probabilities in a distribution
To analyze variance in a dataset
#3
What is the primary purpose of a control group in experimental design?
To serve as a reference group for statistical analyses
To ensure that the experimental group is not affected by confounding variables
To provide a baseline for comparison with the experimental group
To conduct non-parametric analyses
#4
What does the term 'p-hacking' refer to in the context of statistical analysis?
Manipulating data to achieve a statistically significant result
Using a p-value of 0.5 for hypothesis testing
Conducting a power analysis
Randomly selecting participants for a study
#5
What is the purpose of the Shapiro-Wilk test in statistics?
To compare means of two independent groups
To test the normality of a distribution
To analyze variance in a dataset
To compare medians of two independent groups
#6
What is the purpose of stratified sampling in survey design?
To ensure all groups in the population are represented in the sample
To randomly select participants from the population
To collect data from a specific subgroup in the population
To control for confounding variables
#7
Which statistical test is appropriate for comparing means of two independent groups?
Chi-squared test
ANOVA
Paired t-test
Independent samples t-test
#8
Which measure of central tendency is affected by extreme values or outliers?
#9
What is the purpose of a factorial design in experimental research?
To manipulate one independent variable at a time
To investigate the interaction effects of two or more independent variables
To control for confounding variables
To conduct non-parametric analyses
#10
In regression analysis, what does the coefficient of determination (R-squared) measure?
The strength and direction of the relationship between variables
The proportion of the variance in the dependent variable explained by the independent variable(s)
The probability of committing a Type I error
The level of statistical significance
#11
What is the purpose of the Mann-Whitney U test in non-parametric statistics?
To compare means of two independent groups
To test the normality of a distribution
To analyze variance in a dataset
To compare medians of two independent groups
#12
What is the purpose of a confidence interval in statistics?
To determine the statistical power of a test
To estimate the range within which a population parameter is likely to fall
To calculate the p-value of a hypothesis test
To identify outliers in a dataset
#13
What does 'p-value' represent in hypothesis testing?
The probability of committing a Type II error
The probability of obtaining observed results if the null hypothesis is true
The confidence level of the test
The probability of committing a Type I error
#14
Which type of sampling method involves selecting every 'kth' individual from a list or population?
Random sampling
Stratified sampling
Systematic sampling
Convenience sampling
#15
What is the purpose of the Kolmogorov-Smirnov test in statistics?
To compare means of two independent groups
To test the normality of a distribution
To analyze the variance in a dataset
To compare proportions in two samples
#16
What is the formula for calculating standard deviation?
√(Σ(xi - μ)² / N)
Σ(xi - μ) / N
Σ(xi / N)²
Σ(xi - μ)² / N
#17
In survey research, what is the purpose of a Likert scale?
To measure the central tendency of a dataset
To assess the reliability of survey questions
To collect qualitative data
To measure attitudes or opinions using a scale