(a) Let \(X\) be a random variable with characteristic function \(\varphi \). Show that \(X\) is symmetric if and only if \(\varphi (t)\) is real for all \(t\).
(b) Give three distinct examples of real characteristic functions.
Question
Spring 2011 • Question 6
(a) Let \(X\) be a random variable with characteristic function \(\varphi \). Show that \(X\) is symmetric if and only if \(\varphi (t)\) is real for all \(t\).
(b) Give three distinct examples of real characteristic functions.