Expected Value (Leaving Cert Mathematics): Flashcards

Long-term average of random variable

Central tendency

$E(X) = \sum (x \times P(x))$

Value of the random variable

Probability of $x$

$E(X) = \int x \times f(x) \, dx$

Probability density function of $x$

Doesn't necessarily equal any single outcome; represents average over repeated trials

Zero

Economics, insurance, gambling

$3.5$

$0.7$