Covariance between a standard normal and its square
Question
Let be standard normal, and define and . What is ?
Short answer
. , and both and vanish by symmetry of the normal. This is a classic example of uncorrelated yet dependent variables.
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Open the worked solutionLessons behind this question
- Continuous Random Variables and Probability Density Functions
- Covariance and Correlation
- Cumulative Distribution Functions
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