This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
Unformatted text preview: STA 4321/5325 — Spring 2010 Quiz 5 — March 19 Name: K E Y There are ﬁve problems in this quiz. Each problem has exactly one correct answer. Problem 1 Let X be a continuous random variable which takes nonnegative values. Let f (us)
denote the probability density function of X. Then (a) f(m) = 1 for every 1‘ < 0
(b) f(:v) = 0 for every cc < 0
(e) f(x) < 0 for every x < 0
((1) f(x) = 0.5 for every :1: < 0 Problem 2 Let X be a continuous random variable with probability density function f (ac) and
probability distribution function Then for each x E R, (a) F(x) = $1790) (b) F (9:) = f2(£v) (C) F (03) = fix, f(y)dy
(d) F (x) = ﬁg; Problem 3 Let X be a continuous random variable taking nonnegative values, then
E(X) = fO°°(1 — F(at))dx. This statement is (b) False Problem 4 Let X be the uniform random variable on the interval [530, 550]. Then
(a) E(X) = 530 (c) E(X) = 550 (d) E(X) = 20 Problem 5 Let X be the exponential random variable with parameter 5. Then 4 @ HX2®=%u—€ﬂ Limb (b) P(X24)=1—e_ (c) 130(24): ée‘é UIIP (d) P(X 2 4) = e Note that the density function of exponential random variable is Ag? ,forchO
,fora:<0 . %6
MO ...
View
Full Document
 Fall '08
 Staff
 Probability

Click to edit the document details