Question
Show that for $v>2$ the variance of the $t$ distribution with $v$ degrees of freedom is $\frac{v}{v-2} .$ (Hint: Make the substitution $1+\frac{t^{2}}{v}=\frac{1}{u} .$ )
Step 1
For a random variable X with probability density function f(x), the variance is given by: Var(X) = E(X^2) - (E(X))^2 Show more…
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