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Questions and Answers
Variance is the expected value of the absolute deviation from the mean of a random variable.
Variance is the expected value of the absolute deviation from the mean of a random variable.
False (B)
The variance of a sum of uncorrelated random variables is equal to the sum of their variances.
The variance of a sum of uncorrelated random variables is equal to the sum of their variances.
True (A)
The standard deviation is the square root of the variance.
The standard deviation is the square root of the variance.
True (A)
There is only one concept referred to as 'variance' in probability theory and statistics.
There is only one concept referred to as 'variance' in probability theory and statistics.
The units of variance differ from the random variable, unlike the standard deviation.
The units of variance differ from the random variable, unlike the standard deviation.
Flashcards
Variance definition
Variance definition
Expected value of the squared deviation from the mean of a random variable.
Variance of uncorrelated variables
Variance of uncorrelated variables
The variance of a sum equals the sum of individual variances.
Standard Deviation
Standard Deviation
Square root of the variance
Variance in probability
Variance in probability
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Units of Variance vs. Standard Deviation
Units of Variance vs. Standard Deviation
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Study Notes
Variance in Probability Theory and Statistics
- Variance is the expected value of the absolute deviation from the mean of a random variable.
Properties of Variance
- The variance of a sum of uncorrelated random variables is equal to the sum of their variances.
Relationship with Standard Deviation
- The standard deviation is the square root of the variance.
Unique Concept
- There is only one concept referred to as 'variance' in probability theory and statistics.
Units of Variance
- The units of variance differ from the random variable, unlike the standard deviation.
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Description
Test your knowledge of variance, a statistical measure of how far values spread from their average. Understand its relationship with the standard deviation and its role as a measure of dispersion.