f(y) = { c(y - y^2)     0%26lt;=y%26lt;=1
          {   0                otherwise
(a) Determine the value of c.
(b) Calculate (i) P( .6 ≤Y ≤ .9 ), (ii) P( Y ≥ .3 ).
(c) Calculate the mean and variance of Y.
(d) Determine the cumulative distribution function for the random variable.
no idea what to do
A continuous random variable Y has a probability density function given by?
a) value of c = Integral from 0 - to c of f(y) dy
b) use th4e information you have from a)
c) mean : integral from 0 - 1 of f(y) dy / lentgh of interval which is 1
d)  pffff
Reply:Integrate it...
Reply:Let Int mean the integral of a function, then:
a) We need total probability = 1, so Int[f(y) from y=0 to y=1] = 1.
b) Again, using integration.
c)  E[Y] = Int[ y * f(y)]
VAR[Y] = Int[ y^2 * f(y)] - ( E[Y] ) ^ 2
d)  the CDF si given by g(x) = Int[ f(y) from y=-infinity to y = x ]
Steve
Answers:
a) c=6
c) expected value = 1/2, variance = 1/20
d) CDF(x) = 0, x%26lt;0
                  = 3x^2 - 2x^3,     0%26lt;x%26lt;1
                  =1, 1%26lt;x
trading cards
Subscribe to:
Post Comments (Atom)
 
No comments:
Post a Comment