- #1
rabbed
- 243
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Hi
Assume an x-coordinate from the unit circle is picked from a uniform distribution.
This is the outcome of the random variable X with probability density function Xden(x) = 0.5 (-1 < x < 1).
The random variable Y is related to the random variable X by Y = f(X) = √(1-X2) and X = g(Y) = ±√(1-Y2).
What is the probability density function Yden(y)?
Since Yden(y) = Xden(g(y)) / |f'(g(y))|, i first calculate f'(x) = -x/√(1-x2).
Then Yden(y) = Xden( √(1-Y2) ) / f'( √(1-Y2) ) + Xden( -√(1-Y2) ) / f'( -√(1-Y2) )
I get Yden(y) = 0
Where do i go wrong?
Rgds
Rabbed
Assume an x-coordinate from the unit circle is picked from a uniform distribution.
This is the outcome of the random variable X with probability density function Xden(x) = 0.5 (-1 < x < 1).
The random variable Y is related to the random variable X by Y = f(X) = √(1-X2) and X = g(Y) = ±√(1-Y2).
What is the probability density function Yden(y)?
Since Yden(y) = Xden(g(y)) / |f'(g(y))|, i first calculate f'(x) = -x/√(1-x2).
Then Yden(y) = Xden( √(1-Y2) ) / f'( √(1-Y2) ) + Xden( -√(1-Y2) ) / f'( -√(1-Y2) )
I get Yden(y) = 0
Where do i go wrong?
Rgds
Rabbed