[R] Regression with ranges and displaying them in an XY-Plot

[Johannes Radinger]

Hello UseRs,

I've got 3 variables, the dependent variable Y as well as a max and a min value of the independent variable (Xa and Xb) where in some cases Xa=Xb (so actually a single value for X).
First I'd like to perform a regression, but my problem is that my X is a range (acutally a censored independent variable Xa-Xb) rather then one single value. I know already some possible approaches like Bayesian Regression or EM algorithms but I've to dig deeper into that...But any suggestions so far? 

Another question arises: How can I display the ranges in a XY-Plot to just have a look at the data and possibly overlay it with the resulting regression line? How can I do that in R? I'd like to just display a line for every Xa-Xb pair. An idea was also to use the color for the lines depending on the range-length (the longer the more grey, the shorter the more black). Maybe you can give me some tips or some simple sample codes.

Thank you very much
/Johannes
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