Suppose that the joint probability density function of ˜ (X, Y) is given by:´
f X,Y (x,y) = 4x/y3 I(0.1)(x), I (1, ∞)(y).
Calculate
a) P(1/2 < X < 3/4, 0 < Y ≤ 1/3).
b) P(Y > 5).
c) P(Y > X).
Let X and Y have the following joint density function
f(x,y)=k(1-y) , 0≤x≤y≤1.
Find the value of k that makes this a probability density
function.
Compute the probability that P(X≤3/4, Y≥1/2).
Find E(X).
Find E(X|Y=y).
Given the joint density function of X and Y as
fX,Y(x,y) = cx2 + xy/3
0 <x <1 and 0 < y < 2.
complete work shading appropriate regions for all integral
calculations.
Find the expected value of Z =
e(s1X+s2Y) where s1 and
s2 are any constants.
. The joint probability density function of X and Y is given
by
?(?, ?) = { ??^2? ?? 0 ≤ ? ≤ 2, 0 ≤ ?, ??? ? + ? ≤ 1
0 ??ℎ??????
(a) Determine the value of c.
(b) Find the marginal probability density function of X and
Y.
(c) Compute ???(?, ?).
(d) Compute ???(?^2 + ?).
(e) Determine if X and Y are independent
Suppose X and Y have joint probability density function f(x,y) =
6(x-y) when 0<y<x<1 and f(x,y) = 0 otherwise.
(a) Indicate with a sketch the sample space in the x-y plane
(b) Find the marginal density of X, fX(x)
(c) Show that fX(x) is properly normalized, i.e., that it
integrates to 1 on the sample space of X
(d) Find the marginal density of Y, fY(y)
(e) Show that fY(y) is properly normalized, i.e., that it
integrates to 1 on...
4. The joint density function of (X, Y ) is
f(x,y)=2(x+y), 0≤y≤x≤1
. Find the correlation coefficient ρX,Y
.
5. The height of female students in KU follows a normal
distribution with mean 165.3 cm and s.d. 7.3cm. The height of male
students in KU follows a normal distribution with mean 175.2 cm and
s.d. 9.2cm. What is the probability that a random female student is
taller than a male student in KU?
Suppose that X and Y have the following joint probability
density function. f (x, y) = (3/394)*y, 0 < x < 8, y > 0,
x − 3 < y < x + 3
(a) Find E(XY). (b) Find the covariance
between X and Y.
Let X and Y have joint pdf f(x,y)=k(x+y), for 0<=x<=1 and
0<=y<=1.
a) Find k.
b) Find the joint cumulative density function of (X,Y)
c) Find the marginal pdf of X and Y.
d) Find Pr[Y<X2] and Pr[X+Y>0.5]
If the joint probability density function of the random
variables X and Y is given by f(x, y) = (1/4)(x + 2y) for 0 < x
< 2, 0 < y < 1, 0 elsewhere
(a) Find the conditional density of Y given X = x, and use it to
evaluate P (X + Y/2 ≥ 1 | X = 1/2)
(b) Find the conditional mean and the conditional variance of Y
given X = 1/2
(c) Find the variance...
Consider a continuous random vector (Y, X) with joint
probability density function
f(x, y) = 1
for 0 < x < 1, x < y < x + 1.
What is the marginal density of X and Y? Use this to compute
Var(X) and Var(Y)
Compute the expectation E[XY]
Use the previous results to compute the correlation Corr (Y,
X)
Compute the third moment of Y, i.e., E[Y3]