Mean and Variance of a Clipped Normal
Let $Z \sim N(0,1)$. Define the clipped (truncated) variable
$X = \min(\max(Z, -2),\, 2),$
so $X$ equals $Z$ if $|Z| \le 2$, equals $-2$ if $Z < -2$, and equals
$ if $Z > 2$.
1. Compute $E[X]$ and $\text{Var}(X)$ in closed form, expressing your answer in terms of the standard normal pdf $\phi$ and cdf $\Phi$.
2. Without a calculator, approximate $\text{Var}(X)$ to two decimal places, showing your whiteboard steps.