#1
What is the mean of a probability distribution?
The most frequently occurring value
The average value
The highest value
The lowest value
#2
What is the formula for calculating the median of a dataset?
Sum of all values divided by the number of values
Middle value when the data is arranged in ascending order
The value that appears most frequently in the dataset
The difference between the highest and lowest values in the dataset
#3
What is the mode of a dataset?
The average value
The most frequently occurring value
The middle value
The highest value
#4
What is the interquartile range (IQR) in statistics?
The range between the minimum and maximum values
The range between the first and third quartiles
The range between the mean and median
The range between the median and mode
#5
In a box plot, what does the box represent?
The interquartile range
The range of data values
The mean of the dataset
The standard deviation of the dataset
#6
What is the formula for calculating the variance of a dataset?
Sum of squared differences between each data point and the mean
Sum of absolute differences between each data point and the mean
Sum of squared differences between each data point and the median
Sum of absolute differences between each data point and the median
#7
In statistics, what does 'skewness' measure?
The spread of data
The symmetry of a distribution
The central tendency
The variability of data
#8
What does the standard deviation represent in a normal distribution?
The average value
The spread of data around the mean
The highest value
The lowest value
#9
Which of the following is a characteristic of a positively skewed distribution?
Mean < Median < Mode
Mean > Median > Mode
Mean = Median = Mode
Mean < Median > Mode
#10
What does the term 'outlier' refer to in statistics?
A data point that lies within the normal range
A data point that is significantly different from other observations
The average value of a dataset
A data point that is missing from the dataset
#11
Which measure of central tendency is affected most by outliers?
Mean
Median
Mode
All measures equally
#12
What is a p-value in hypothesis testing?
The probability of making a Type I error
The probability of making a Type II error
The level of significance
The probability of observing a test statistic as extreme or more extreme than the one observed, assuming the null hypothesis is true
#13
What is the concept of kurtosis in statistics?
It measures the peakedness of a distribution
It measures the spread of data
It measures the symmetry of a distribution
It measures the variability of data
#14
What is the purpose of a Q-Q plot in statistics?
To compare two different distributions
To assess the normality of a distribution
To measure the spread of data
To identify outliers in a dataset
#15
What is the purpose of a probability density function (PDF) in statistics?
To represent the cumulative distribution function
To estimate probabilities of continuous random variables
To calculate probabilities of discrete random variables
To compare two different distributions
#16
What is a Type I error in hypothesis testing?
Rejecting the null hypothesis when it is true
Failing to reject the null hypothesis when it is false
Rejecting the alternative hypothesis when it is true
Failing to reject the alternative hypothesis when it is false
#17
What does the term 'heteroscedasticity' refer to in regression analysis?
Unequal variance of the errors in a regression model
Equal variance of the errors in a regression model
Nonlinear relationship between variables in a regression model
Linear relationship between variables in a regression model