Let be a normally distributed random variable with mean 0 and variance . Then, the mean of is
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DSE 2010 Question 47: Random variables and standard distributions
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Let X be a normally distributed random variable with mean 0 and variance σ². Then, the mean of X² is (A) 0 (B) σ (C) 2σ (D) σ²
Also written as: Let X be a normally distributed random variable with mean 0 and variance sigma^2. Then, the mean of X^2 is
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What this question tests
This question is on Expectation and variance, part of Random variables and standard distributions in Statistics.
The mean and spread of a random variable, and how they change under transformations and sums.
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