Related Articles

Related Articles

GATE | GATE CS 2011 | Question 18
  • Last Updated : 03 Dec, 2013

If the difference between expectation of the square of a random variable (E[X²]) and the square of the expectation of the random variable (E[X])² is denoted by R, then?
(A) R = 0
(B) R < 0
(C) R >= 0
(D) R > 0


Answer: (C)

Explanation: The difference between  (E[X²]) and (E[X])² is called variance of a random variable.  Variance measures how far a set of numbers is spread out. (A variance of zero indicates that all the values are identical.) A non-zero variance is always positive:

Quiz of this Question

sudo-gate-course

My Personal Notes arrow_drop_up
Recommended Articles
Page :