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The correlation between independent random variables is always 0. This is true because the variances of the random variables are well defined. **Detailed Explanation:** 1. **Definition of Correlation:** Correlation measures the linear relationship between two random variables. The correlation coefficient ρ between two random variables X and Y is defined as: ρ = Cov(X,Y) / (σₓ * σᵧ) where Cov(X,Y) is the covariance between X and Y, and σₓ and σᵧ are the standard deviations of X and Y respectively. 2. **Independence and Covariance:** For independent random variables, the covariance is always 0. This is because: Cov(X,Y) = E[XY] - E[X]E[Y] For independent variables, E[XY] = E[X]E[Y], so Cov(X,Y) = 0. 3. **Correlation Calculation:** If Cov(X,Y) = 0, then regardless of the standard deviations (which are positive and well-defined as given in the question), the correlation ρ = 0 / (σₓ * σᵧ) = 0. 4. **Key Points:** - Independence implies zero correlation - However, zero correlation does NOT necessarily imply independence (it only implies no linear relationship) - The condition of "well-defined variances" ensures that the correlation calculation is valid (no division by zero) Therefore, for independent random variables with well-defined variances, the correlation is always 0.
Author: Nikitesh Somanthe
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