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Subject: probability based on trials of 2 variables
Date: Thu, 29 Apr 2010 16:10:22 +0000 (UTC)
Organization: Haifa University
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There are 2 variables:
X, that has values in range Xr,
Y, that generally can have values in some other range Yr, but for given X has more chances to be in some narrow (confidence) interval.
There is also a set of measurments of couples (X, Y). It can include couples with same X and different Ys.

The question is: given additional pair of values (xx, yy), how can I know the probability to receive a this yy for this xx? Is there a Matlab function that can calculate mean and variance for given xx? I can't find it!
If the function does not exist, it can be implemented like this:
  Collect pairs (X, Y) with xx-eps <X< xx+eps, with some small eps
  Calculate probability distribution for those Ys, maybe giving more weight to Ys whose X is closer to xx.
I just do not want to implement something that already exists.