Uniform pdf from difference of two stochastic variables?

AI Thread Summary
The discussion revolves around finding a probability distribution D such that the difference Y = X1 - X2, where X1 and X2 are independent random variables from D, results in a uniform distribution on the interval [0,1]. The initial suggestion involves using a characteristic function related to a uniform distribution on (-1/2, 1/2) and applying the inverse Fourier transform. However, the user encountered difficulties in calculating the inverse Fourier transform using Mathematica, leading to doubts about the existence of such a distribution. There is speculation that a density function may not exist for this scenario. The conversation concludes with a recommendation to explore a more mathematical forum for further assistance.
bemortu
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Hi,

I'm trying to find a probability distribution (D) with the following property:
Given two independent stochastic variables X1 and X2 from the distribution D, I want the difference Y=X1-X2 to have a uniform distribution (one the interval [0,1], say).

I don't seem to be able to solve it. I'm not even sure that such a distribution exists...

Any ideas?
 
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Sugestion (outline). For simplicity I will make it uniform on the interval (-1/2,1/2). The characteristic function is sin(t/2)/(t/2). Take the square root and then the inverse Fourier transform should give you something close to what you want (the sum of two random variables will have a uniform distribution).
 
Yes, that's one of the things I already tried. The problem is that I didn't manage to calculate that inverse Fourier transform. I tried it with Mathematica, which could not find an analytical solution. I also tried the numerical inverse Fourier transform in Mathematica but it also failed. Maybe it means that this distribution doesn't exist?
 
My guess: there is no density function. You might try getting the distribution function.

F(y) - F(x) = 1/2π ∫{(exp(ity) - exp(itx))φ(t)/(it)}dt
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http://mathforum.org/kb/forumcategory.jspa?categoryID=16

You might try the above forum - it is more mathematical.
 
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