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cardinal
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Are $\hat{\beta}_{\text{ls}}$ and $S^2$ independtindependent if errors are not normally distributed?

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Manuel
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About the Independece of Are $\hat{\beta}_{\text{ls}}$ and $S^2$ independt if errors are not normally distributed?

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Manuel
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About the Independece of $\hat{\beta}_{\text{ls}}$ and $S^2$

When estimating a linear model $$ Y_i = X_i\beta + \varepsilon_i \quad \quad 1\leq i\leq n$$ We have $\hat{\beta}$ the least squares estimation of the slope and the estimation of the variance, $S^2 = \frac{1}{n-2}\sum_{i=1}^nr_i^2$ where $r_i$ are the residuals for the least squares estimation.

When the errors are independent and $\varepsilon_i \sim \mathcal{N}\left(0,\sigma^2\right)$ it is possible to prove that $\hat{\beta}$ and $S^2$ are independent statistics.

Does independence hold if we drop the normality assumption? Just assuming If we drop the normality. And we only assume independent and identically distributed errors with zero mean and variance $\sigma^2$. Does independence of the statistics still hold?

If it doesn't, is there a characterization of the distributions that turn into independent statistics?

About the Independece of $\hat{\beta}$ and $S^2$

When estimating a linear model $$ Y_i = X_i\beta + \varepsilon_i \quad \quad 1\leq i\leq n$$ We have $\hat{\beta}$ the least squares estimation of the slope and the estimation of the variance, $S^2 = \frac{1}{n-2}\sum_{i=1}^nr_i^2$ where $r_i$ are the residuals for the least squares estimation.

When the errors are independent and $\varepsilon_i \sim \mathcal{N}\left(0,\sigma^2\right)$ it is possible to prove that $\hat{\beta}$ and $S^2$ are independent statistics.

Does independence hold if we drop the normality assumption? Just assuming independent and identically distributed errors with zero mean and variance $\sigma^2$.

If it doesn't, is there a characterization of the distributions that turn into independent statistics?

About the Independece of $\hat{\beta}_{\text{ls}}$ and $S^2$

When estimating a linear model $$ Y_i = X_i\beta + \varepsilon_i \quad \quad 1\leq i\leq n$$ We have $\hat{\beta}$ the least squares estimation of the slope and the estimation of the variance, $S^2 = \frac{1}{n-2}\sum_{i=1}^nr_i^2$ where $r_i$ are the residuals for the least squares estimation.

When the errors are independent and $\varepsilon_i \sim \mathcal{N}\left(0,\sigma^2\right)$ it is possible to prove that $\hat{\beta}$ and $S^2$ are independent statistics.

If we drop the normality. And we only assume independent and identically distributed errors with zero mean and variance $\sigma^2$. Does independence of the statistics still hold?

If it doesn't, is there a characterization of the distributions that turn into independent statistics?

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Manuel
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