#1
In a normal distribution, what percentage of data falls within one standard deviation of the mean?
#2
What does the term 'p-value' stand for in statistics?
Probability-value
Population-value
Parameter-value
Percentage-value
#3
Which measure of central tendency is most affected by outliers?
#4
What does the standard deviation measure in a set of data?
Central tendency
Variability
Skewness
Frequency
#5
Which graphical representation is suitable for displaying the distribution of a continuous variable?
Bar chart
Histogram
Pie chart
Line chart
#6
What is the purpose of a confidence interval in statistics?
To determine the standard deviation of a sample
To estimate the population parameter with a range of values
To test for the normality of a distribution
To calculate the mean of a dataset
#7
Which statistical test is appropriate for comparing means of more than two independent groups?
Paired t-test
Wilcoxon rank-sum test
Analysis of Variance (ANOVA)
Mann-Whitney U test
#8
In a normal distribution, what is the relationship between the mean, median, and mode?
They are all equal
Mean = Median = Mode
Mean > Median > Mode
Mean < Median < Mode
#9
Which measure of variability is resistant to outliers?
Range
Interquartile Range (IQR)
Standard Deviation
Variance
#10
What is the primary purpose of a scatter plot in statistical analysis?
To display the distribution of a single variable
To show the relationship between two continuous variables
To compare means of different groups
To assess the normality of a dataset
#11
Which type of sampling method involves selecting every kth individual from the population?
Stratified sampling
Random sampling
Systematic sampling
Cluster sampling
#12
When is a type I error committed in hypothesis testing?
Rejecting a true null hypothesis
Failing to reject a false null hypothesis
Incorrectly estimating a population parameter
Failing to observe an effect that is present
#13
Which statistical test is appropriate for comparing means of two related groups?
Chi-square test
t-test
ANOVA
Paired t-test
#14
In regression analysis, what does a negative coefficient indicate?
A positive correlation between variables
A negative correlation between variables
No correlation between variables
Perfect correlation between variables
#15
Which statistical test is used to determine if there is a significant association between two categorical variables?
t-test
Chi-square test
ANOVA
Correlation coefficient
#16
What is the purpose of regression analysis in statistics?
To describe patterns in data
To test for causation
To predict one variable based on another
To calculate probabilities
#17
What does p-value represent in hypothesis testing?
Probability of making a Type I error
Probability of making a Type II error
Probability of obtaining the observed results if the null hypothesis is true
Probability of rejecting the null hypothesis
#18
What is the primary advantage of using a box plot in data visualization?
Displays the frequency distribution
Highlights outliers in the data
Shows the trend over time
Provides a detailed summary statistics
#19
What is the purpose of the coefficient of determination (R-squared) in regression analysis?
To measure the strength of the relationship between variables
To assess the statistical significance of coefficients
To evaluate the goodness of fit of the regression model
To determine the direction of the relationship
#20
What does a two-tailed hypothesis test assess?
If the sample mean is significantly different from the population mean
If there is a significant relationship between two variables
If the effect size is practically significant
If there is a significant difference in both directions
#21
What is the formula for calculating the z-score of a data point in a normal distribution?
(X - μ) / σ
(X - μ) * σ
(X + μ) / σ
(X + μ) * σ
#22
When is the Mann-Whitney U test appropriate in statistical analysis?
To compare means of two independent groups
To assess the normality of a distribution
To analyze the correlation between two variables
To compare medians of two independent groups
#23
What is the purpose of a Q-Q plot in statistics?
To compare two datasets
To visualize the distribution of a single variable
To check the normality of a dataset
To display summary statistics
#24
What is the primary purpose of the chi-square goodness-of-fit test?
To compare means of two independent groups
To analyze the relationship between two variables
To test if observed frequencies match expected frequencies in a distribution
To assess the normality of a dataset
#25
What does the term 'p-hacking' refer to in the context of statistical analysis?
Manipulating data to achieve statistical significance
Calculating the p-value incorrectly
Ignoring outliers in the dataset
Using a small sample size